Round two cleans up a few misc script and build items, adds a shadow variable test, and reduces the total livepatch kselftest runtime to ~45 seconds.
The tests run on top of Petr's v11 atomic replace feature and v2 of the shadow variable enhancement patchsets:
[PATCH 0/8] livepatch: Atomic replace feature https://lkml.kernel.org/r/20180323120028.31451-1-pmladek@suse.com
[PATCH v2 0/2] livepatch: Allocate and free shadow variables more safely https://lkml.kernel.org/r/20180405122315.29065-1-pmladek@suse.com
Questions for v3:
- Should we split off the atomic replace and shadow variable update tests so that the this patchset could be merged before the ones listed above?
- I didn't remove any of the sample modules. If anyone thinks any of them should go, let me know. They serve as nice, simple examples so I thought they should all stay.
- Module naming convention: to make the test script easier to grep module names and filenames, I broke with livepatch convention and used underscores instead of dashes. I didn't think it worth the regex foo to flip back and forth in the test script.
- More tests from Libor and Nicolai would be welcome! -- Maybe we separate quicktests (like these) from longer tests if needed?
Here's a sample output from a successful test run:
% time make -C tools/testing/selftests TARGETS=livepatch run_tests make: Entering directory `/root/linux/tools/testing/selftests' make[1]: Entering directory `/root/linux/tools/testing/selftests/livepatch' make[1]: Nothing to be done for `all'. make[1]: Leaving directory `/root/linux/tools/testing/selftests/livepatch' make[1]: Entering directory `/root/linux/tools/testing/selftests/livepatch' TAP version 13 selftests: test-livepatch.sh ======================================== TEST: basic function patching ... ok TEST: multiple livepatches ... ok TEST: atomic replace livepatch ... ok ok 1..1 selftests: test-livepatch.sh [PASS] selftests: test-callbacks.sh ======================================== TEST: target module before livepatch ... ok TEST: module_coming notifier ... ok TEST: module_going notifier ... ok TEST: module_coming and module_going notifiers ... ok TEST: target module not present ... ok TEST: pre-patch callback -ENODEV ... ok TEST: module_coming + pre-patch callback -ENODEV ... ok TEST: multiple target modules ... ok TEST: busy target module ... ok TEST: multiple livepatches ... ok TEST: atomic replace ... ok ok 1..2 selftests: test-callbacks.sh [PASS] selftests: test-shadow-vars.sh ======================================== TEST: basic shadow variable API ... ok ok 1..3 selftests: test-shadow-vars.sh [PASS] make[1]: Leaving directory `/root/linux/tools/testing/selftests/livepatch' make: Leaving directory `/root/linux/tools/testing/selftests'
real 0m46.166s user 0m0.436s sys 0m1.244s
changes from v1: - Only add $(CC_FLAGS_FTRACE) for target modules - Remove between test delay - Reduce RETRY_INTERVAL to .1 sec - Reduce test_callback_mod's busymod_work_func delay from 60 to 10 sec - s/PASS/ok and s/FAIL/not ok for test output - Move test descriptions from Documentation/livepatch/callbacks.txt into tools/testing/selftests/livepatch/test-callbacks.sh - Add a shadow variable test script and module - Add a short tools/testing/selftests/livepatch/README - to += linux-kselftest@vger.kernel.org - cc += Libor, Nicolai, Artem
change from rfc: - SPDX-License-Identifiers - Moved livepatch test modules into lib/livepatch - Renamed livepatch.sh (filename suffix) - Reduced between-test delay time - Split off common functions.sh file - Split into separate livepatch, callbacks, and shadow-vars scrips - Gave the tests short descriptions instead of TEST1, TEST2, etc.
Joe Lawrence (1): selftests/livepatch: introduce tests
Documentation/livepatch/callbacks.txt | 487 ----------------- lib/Kconfig.debug | 12 + lib/Makefile | 2 + lib/livepatch/Makefile | 15 + lib/livepatch/test_klp_atomic_replace.c | 69 +++ lib/livepatch/test_klp_callbacks_busy.c | 43 ++ lib/livepatch/test_klp_callbacks_demo.c | 132 +++++ lib/livepatch/test_klp_callbacks_demo2.c | 104 ++++ lib/livepatch/test_klp_callbacks_mod.c | 24 + lib/livepatch/test_klp_livepatch.c | 62 +++ lib/livepatch/test_klp_shadow_vars.c | 235 ++++++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/livepatch/Makefile | 8 + tools/testing/selftests/livepatch/config | 1 + tools/testing/selftests/livepatch/functions.sh | 196 +++++++ .../testing/selftests/livepatch/test-callbacks.sh | 607 +++++++++++++++++++++ .../testing/selftests/livepatch/test-livepatch.sh | 173 ++++++ .../selftests/livepatch/test-shadow-vars.sh | 60 ++ 18 files changed, 1744 insertions(+), 487 deletions(-) create mode 100644 lib/livepatch/Makefile create mode 100644 lib/livepatch/test_klp_atomic_replace.c create mode 100644 lib/livepatch/test_klp_callbacks_busy.c create mode 100644 lib/livepatch/test_klp_callbacks_demo.c create mode 100644 lib/livepatch/test_klp_callbacks_demo2.c create mode 100644 lib/livepatch/test_klp_callbacks_mod.c create mode 100644 lib/livepatch/test_klp_livepatch.c create mode 100644 lib/livepatch/test_klp_shadow_vars.c create mode 100644 tools/testing/selftests/livepatch/Makefile create mode 100644 tools/testing/selftests/livepatch/config create mode 100644 tools/testing/selftests/livepatch/functions.sh create mode 100755 tools/testing/selftests/livepatch/test-callbacks.sh create mode 100755 tools/testing/selftests/livepatch/test-livepatch.sh create mode 100755 tools/testing/selftests/livepatch/test-shadow-vars.sh
-- 1.8.3.1
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Add a few livepatch modules and simple target modules that the included regression suite can run tests against.
Signed-off-by: Joe Lawrence joe.lawrence@redhat.com --- Documentation/livepatch/callbacks.txt | 487 ----------------- lib/Kconfig.debug | 12 + lib/Makefile | 2 + lib/livepatch/Makefile | 15 + lib/livepatch/test_klp_atomic_replace.c | 69 +++ lib/livepatch/test_klp_callbacks_busy.c | 43 ++ lib/livepatch/test_klp_callbacks_demo.c | 132 +++++ lib/livepatch/test_klp_callbacks_demo2.c | 104 ++++ lib/livepatch/test_klp_callbacks_mod.c | 24 + lib/livepatch/test_klp_livepatch.c | 62 +++ lib/livepatch/test_klp_shadow_vars.c | 235 ++++++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/livepatch/Makefile | 8 + tools/testing/selftests/livepatch/config | 1 + tools/testing/selftests/livepatch/functions.sh | 196 +++++++ .../testing/selftests/livepatch/test-callbacks.sh | 607 +++++++++++++++++++++ .../testing/selftests/livepatch/test-livepatch.sh | 173 ++++++ .../selftests/livepatch/test-shadow-vars.sh | 60 ++ 18 files changed, 1744 insertions(+), 487 deletions(-) create mode 100644 lib/livepatch/Makefile create mode 100644 lib/livepatch/test_klp_atomic_replace.c create mode 100644 lib/livepatch/test_klp_callbacks_busy.c create mode 100644 lib/livepatch/test_klp_callbacks_demo.c create mode 100644 lib/livepatch/test_klp_callbacks_demo2.c create mode 100644 lib/livepatch/test_klp_callbacks_mod.c create mode 100644 lib/livepatch/test_klp_livepatch.c create mode 100644 lib/livepatch/test_klp_shadow_vars.c create mode 100644 tools/testing/selftests/livepatch/Makefile create mode 100644 tools/testing/selftests/livepatch/config create mode 100644 tools/testing/selftests/livepatch/functions.sh create mode 100755 tools/testing/selftests/livepatch/test-callbacks.sh create mode 100755 tools/testing/selftests/livepatch/test-livepatch.sh create mode 100755 tools/testing/selftests/livepatch/test-shadow-vars.sh
diff --git a/Documentation/livepatch/callbacks.txt b/Documentation/livepatch/callbacks.txt index c9776f48e458..6ca2801a6bb9 100644 --- a/Documentation/livepatch/callbacks.txt +++ b/Documentation/livepatch/callbacks.txt @@ -116,490 +116,3 @@ virtnet_probe() initialized its driver's net_device features. A pre/post-patch callback could iterate over all such devices, making a similar change to their hw_features value. (Client functions of the value may need to be updated accordingly.) - - -Test cases -========== - -What follows is not an exhaustive test suite of every possible livepatch -pre/post-(un)patch combination, but a selection that demonstrates a few -important concepts. Each test case uses the kernel modules located in -the samples/livepatch/ and assumes that no livepatches are loaded at the -beginning of the test. - - -Test 1 ------- - -Test a combination of loading a kernel module and a livepatch that -patches a function in the first module. (Un)load the target module -before the livepatch module: - -- load target module -- load livepatch -- disable livepatch -- unload target module -- unload livepatch - -First load a target module: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 34.475708] livepatch_callbacks_mod: livepatch_callbacks_mod_init - -On livepatch enable, before the livepatch transition starts, pre-patch -callbacks are executed for vmlinux and livepatch_callbacks_mod (those -klp_objects currently loaded). After klp_objects are patched according -to the klp_patch, their post-patch callbacks run and the transition -completes: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 36.503719] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 36.504213] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 36.504238] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 36.504721] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 36.505849] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 37.727133] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 37.727232] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 37.727860] livepatch_callbacks_demo: post_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 37.728792] livepatch: 'livepatch_callbacks_demo': patching complete - -Similarly, on livepatch disable, pre-patch callbacks run before the -unpatching transition starts. klp_objects are reverted, post-patch -callbacks execute and the transition completes: - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 38.510209] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 38.510234] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 38.510982] livepatch_callbacks_demo: pre_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 38.512209] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 39.711132] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 39.711210] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 39.711779] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 39.712735] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 42.534183] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - - -Test 2 ------- - -This test is similar to the previous test, but (un)load the livepatch -module before the target kernel module. This tests the livepatch core's -module_coming handler: - -- load livepatch -- load target module -- disable livepatch -- unload livepatch -- unload target module - - -On livepatch enable, only pre/post-patch callbacks are executed for -currently loaded klp_objects, in this case, vmlinux: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 44.553328] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 44.553997] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 44.554049] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 44.554845] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 45.727128] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 45.727212] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 45.727961] livepatch: 'livepatch_callbacks_demo': patching complete - -When a targeted module is subsequently loaded, only its pre/post-patch -callbacks are executed: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 46.560845] livepatch: applying patch 'livepatch_callbacks_demo' to loading module 'livepatch_callbacks_mod' - [ 46.561988] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 46.563452] livepatch_callbacks_demo: post_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 46.565495] livepatch_callbacks_mod: livepatch_callbacks_mod_init - -On livepatch disable, all currently loaded klp_objects' (vmlinux and -livepatch_callbacks_mod) pre/post-unpatch callbacks are executed: - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 48.568885] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 48.568910] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 48.569441] livepatch_callbacks_demo: pre_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 48.570502] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 49.759091] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 49.759171] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 49.759742] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 49.760690] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 52.592283] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - - -Test 3 ------- - -Test loading the livepatch after a targeted kernel module, then unload -the kernel module before disabling the livepatch. This tests the -livepatch core's module_going handler: - -- load target module -- load livepatch -- unload target module -- disable livepatch -- unload livepatch - -First load a target module, then the livepatch: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 54.607948] livepatch_callbacks_mod: livepatch_callbacks_mod_init - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 56.613919] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 56.614411] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 56.614436] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 56.614818] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 56.615656] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 57.759070] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 57.759147] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 57.759621] livepatch_callbacks_demo: post_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_LIVE] Normal state - [ 57.760307] livepatch: 'livepatch_callbacks_demo': patching complete - -When a target module is unloaded, the livepatch is only reverted from -that klp_object (livepatch_callbacks_mod). As such, only its pre and -post-unpatch callbacks are executed when this occurs: - - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 58.623409] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - [ 58.623903] livepatch_callbacks_demo: pre_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - [ 58.624658] livepatch: reverting patch 'livepatch_callbacks_demo' on unloading module 'livepatch_callbacks_mod' - [ 58.625305] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - -When the livepatch is disabled, pre and post-unpatch callbacks are run -for the remaining klp_object, vmlinux: - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 60.638420] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 60.638444] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 60.638996] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 61.727088] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 61.727165] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 61.727985] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - - -Test 4 ------- - -This test is similar to the previous test, however the livepatch is -loaded first. This tests the livepatch core's module_coming and -module_going handlers: - -- load livepatch -- load target module -- unload target module -- disable livepatch -- unload livepatch - -First load the livepatch: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 64.661552] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 64.662147] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 64.662175] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 64.662850] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 65.695056] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 65.695147] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 65.695561] livepatch: 'livepatch_callbacks_demo': patching complete - -When a targeted kernel module is subsequently loaded, only its -pre/post-patch callbacks are executed: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 66.669196] livepatch: applying patch 'livepatch_callbacks_demo' to loading module 'livepatch_callbacks_mod' - [ 66.669882] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 66.670744] livepatch_callbacks_demo: post_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 66.672873] livepatch_callbacks_mod: livepatch_callbacks_mod_init - -When the target module is unloaded, the livepatch is only reverted from -the livepatch_callbacks_mod klp_object. As such, only pre and -post-unpatch callbacks are executed when this occurs: - - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 68.680065] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - [ 68.680688] livepatch_callbacks_demo: pre_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - [ 68.681452] livepatch: reverting patch 'livepatch_callbacks_demo' on unloading module 'livepatch_callbacks_mod' - [ 68.682094] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 70.689225] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 70.689256] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 70.689882] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 71.711080] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 71.711481] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 71.711988] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - - -Test 5 ------- - -A simple test of loading a livepatch without one of its patch target -klp_objects ever loaded (livepatch_callbacks_mod): - -- load livepatch -- disable livepatch -- unload livepatch - -Load the livepatch: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 74.711081] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 74.711595] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 74.711639] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 74.712272] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 75.743137] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 75.743219] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 75.743867] livepatch: 'livepatch_callbacks_demo': patching complete - -As expected, only pre/post-(un)patch handlers are executed for vmlinux: - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 76.716254] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 76.716278] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 76.716666] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 77.727089] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 77.727194] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 77.727907] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - - -Test 6 ------- - -Test a scenario where a vmlinux pre-patch callback returns a non-zero -status (ie, failure): - -- load target module -- load livepatch -ENODEV -- unload target module - -First load a target module: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 80.740520] livepatch_callbacks_mod: livepatch_callbacks_mod_init - -Load the livepatch module, setting its 'pre_patch_ret' value to -19 -(-ENODEV). When its vmlinux pre-patch callback executed, this status -code will propagate back to the module-loading subsystem. The result is -that the insmod command refuses to load the livepatch module: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko pre_patch_ret=-19 - [ 82.747326] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 82.747743] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 82.747767] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 82.748237] livepatch: pre-patch callback failed for object 'vmlinux' - [ 82.748637] livepatch: failed to enable patch 'livepatch_callbacks_demo' - [ 82.749059] livepatch: 'livepatch_callbacks_demo': canceling transition, going to unpatch - [ 82.749060] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 82.749868] livepatch: 'livepatch_callbacks_demo': unpatching complete - [ 82.765809] insmod: ERROR: could not insert module samples/livepatch/livepatch-callbacks-demo.ko: No such device - - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 84.774238] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - - -Test 7 ------- - -Similar to the previous test, setup a livepatch such that its vmlinux -pre-patch callback returns success. However, when a targeted kernel -module is later loaded, have the livepatch return a failing status code: - -- load livepatch -- setup -ENODEV -- load target module -- disable livepatch -- unload livepatch - -Load the livepatch, notice vmlinux pre-patch callback succeeds: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 86.787845] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 86.788325] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 86.788427] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 86.788821] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 87.711069] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 87.711143] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 87.711886] livepatch: 'livepatch_callbacks_demo': patching complete - -Set a trap so subsequent pre-patch callbacks to this livepatch will -return -ENODEV: - - % echo -19 > /sys/module/livepatch_callbacks_demo/parameters/pre_patch_ret - -The livepatch pre-patch callback for subsequently loaded target modules -will return failure, so the module loader refuses to load the kernel -module. Notice that no post-patch or pre/post-unpatch callbacks are -executed for this klp_object: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 90.796976] livepatch: applying patch 'livepatch_callbacks_demo' to loading module 'livepatch_callbacks_mod' - [ 90.797834] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 90.798900] livepatch: pre-patch callback failed for object 'livepatch_callbacks_mod' - [ 90.799652] livepatch: patch 'livepatch_callbacks_demo' failed for module 'livepatch_callbacks_mod', refusing to load module 'livepatch_callbacks_mod' - [ 90.819737] insmod: ERROR: could not insert module samples/livepatch/livepatch-callbacks-mod.ko: No such device - -However, pre/post-unpatch callbacks run for the vmlinux klp_object: - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 92.823547] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 92.823573] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 92.824331] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 93.727128] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 93.727327] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 93.727861] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - - -Test 8 ------- - -Test loading multiple targeted kernel modules. This test-case is -mainly for comparing with the next test-case. - -- load busy target module (0s sleep), -- load livepatch -- load target module -- unload target module -- disable livepatch -- unload livepatch -- unload busy target module - - -Load a target "busy" kernel module which kicks off a worker function -that immediately exits: - - % insmod samples/livepatch/livepatch-callbacks-busymod.ko sleep_secs=0 - [ 96.910107] livepatch_callbacks_busymod: livepatch_callbacks_mod_init - [ 96.910600] livepatch_callbacks_busymod: busymod_work_func, sleeping 0 seconds ... - [ 96.913024] livepatch_callbacks_busymod: busymod_work_func exit - -Proceed with loading the livepatch and another ordinary target module, -notice that the post-patch callbacks are executed and the transition -completes quickly: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 98.917892] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 98.918426] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 98.918453] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 98.918955] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_busymod -> [MODULE_STATE_LIVE] Normal state - [ 98.923835] livepatch: 'livepatch_callbacks_demo': starting patching transition - [ 99.743104] livepatch: 'livepatch_callbacks_demo': completing patching transition - [ 99.743156] livepatch_callbacks_demo: post_patch_callback: vmlinux - [ 99.743679] livepatch_callbacks_demo: post_patch_callback: livepatch_callbacks_busymod -> [MODULE_STATE_LIVE] Normal state - [ 99.744616] livepatch: 'livepatch_callbacks_demo': patching complete - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 100.930955] livepatch: applying patch 'livepatch_callbacks_demo' to loading module 'livepatch_callbacks_mod' - [ 100.931668] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 100.932645] livepatch_callbacks_demo: post_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 100.934125] livepatch_callbacks_mod: livepatch_callbacks_mod_init - - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 102.942805] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - [ 102.943640] livepatch_callbacks_demo: pre_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - [ 102.944585] livepatch: reverting patch 'livepatch_callbacks_demo' on unloading module 'livepatch_callbacks_mod' - [ 102.945455] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 104.953815] livepatch: 'livepatch_callbacks_demo': initializing unpatching transition - [ 104.953838] livepatch_callbacks_demo: pre_unpatch_callback: vmlinux - [ 104.954431] livepatch_callbacks_demo: pre_unpatch_callback: livepatch_callbacks_busymod -> [MODULE_STATE_LIVE] Normal state - [ 104.955426] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 106.719073] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 106.722633] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 106.723282] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_busymod -> [MODULE_STATE_LIVE] Normal state - [ 106.724279] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - % rmmod samples/livepatch/livepatch-callbacks-busymod.ko - [ 108.975660] livepatch_callbacks_busymod: livepatch_callbacks_mod_exit - - -Test 9 ------- - -A similar test as the previous one, but force the "busy" kernel module -to do longer work. - -The livepatching core will refuse to patch a task that is currently -executing a to-be-patched function -- the consistency model stalls the -current patch transition until this safety-check is met. Test a -scenario where one of a livepatch's target klp_objects sits on such a -function for a long time. Meanwhile, load and unload other target -kernel modules while the livepatch transition is in progress. - -- load busy target module (30s sleep) -- load livepatch -- load target module -- unload target module -- disable livepatch -- unload livepatch -- unload busy target module - - -Load the "busy" kernel module, this time make it do 30 seconds worth of -work: - - % insmod samples/livepatch/livepatch-callbacks-busymod.ko sleep_secs=30 - [ 110.993362] livepatch_callbacks_busymod: livepatch_callbacks_mod_init - [ 110.994059] livepatch_callbacks_busymod: busymod_work_func, sleeping 30 seconds ... - -Meanwhile, the livepatch is loaded. Notice that the patch transition -does not complete as the targeted "busy" module is sitting on a -to-be-patched function: - - % insmod samples/livepatch/livepatch-callbacks-demo.ko - [ 113.000309] livepatch: enabling patch 'livepatch_callbacks_demo' - [ 113.000764] livepatch: 'livepatch_callbacks_demo': initializing patching transition - [ 113.000791] livepatch_callbacks_demo: pre_patch_callback: vmlinux - [ 113.001289] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_busymod -> [MODULE_STATE_LIVE] Normal state - [ 113.005208] livepatch: 'livepatch_callbacks_demo': starting patching transition - -Load a second target module (this one is an ordinary idle kernel -module). Note that *no* post-patch callbacks will be executed while the -livepatch is still in transition: - - % insmod samples/livepatch/livepatch-callbacks-mod.ko - [ 115.012740] livepatch: applying patch 'livepatch_callbacks_demo' to loading module 'livepatch_callbacks_mod' - [ 115.013406] livepatch_callbacks_demo: pre_patch_callback: livepatch_callbacks_mod -> [MODULE_STATE_COMING] Full formed, running module_init - [ 115.015315] livepatch_callbacks_mod: livepatch_callbacks_mod_init - -Request an unload of the simple kernel module. The patch is still -transitioning, so its pre-unpatch callbacks are skipped: - - % rmmod samples/livepatch/livepatch-callbacks-mod.ko - [ 117.022626] livepatch_callbacks_mod: livepatch_callbacks_mod_exit - [ 117.023376] livepatch: reverting patch 'livepatch_callbacks_demo' on unloading module 'livepatch_callbacks_mod' - [ 117.024533] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_mod -> [MODULE_STATE_GOING] Going away - -Finally the livepatch is disabled. Since none of the patch's -klp_object's post-patch callbacks executed, the remaining klp_object's -pre-unpatch callbacks are skipped: - - % echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled - [ 119.035408] livepatch: 'livepatch_callbacks_demo': reversing transition from patching to unpatching - [ 119.035485] livepatch: 'livepatch_callbacks_demo': starting unpatching transition - [ 119.711166] livepatch: 'livepatch_callbacks_demo': completing unpatching transition - [ 119.714179] livepatch_callbacks_demo: post_unpatch_callback: vmlinux - [ 119.714653] livepatch_callbacks_demo: post_unpatch_callback: livepatch_callbacks_busymod -> [MODULE_STATE_LIVE] Normal state - [ 119.715437] livepatch: 'livepatch_callbacks_demo': unpatching complete - - % rmmod samples/livepatch/livepatch-callbacks-demo.ko - % rmmod samples/livepatch/livepatch-callbacks-busymod.ko - [ 141.279111] livepatch_callbacks_busymod: busymod_work_func exit - [ 141.279760] livepatch_callbacks_busymod: livepatch_callbacks_mod_exit diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 64155e310a9f..e4a0e81542ff 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1932,6 +1932,18 @@ config TEST_DEBUG_VIRTUAL
If unsure, say N.
+config TEST_LIVEPATCH + tristate "Test livepatching" + default n + depends on LIVEPATCH + depends on m + help + Test various kernel livepatching features for correctness. + The tests will load test modules that will be livepatched + in various scenarios. + + If unsure, say N. + endif # RUNTIME_TESTING_MENU
config MEMTEST diff --git a/lib/Makefile b/lib/Makefile index a90d4fcd748f..98a38441afb0 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -67,6 +67,8 @@ obj-$(CONFIG_TEST_PARMAN) += test_parman.o obj-$(CONFIG_TEST_KMOD) += test_kmod.o obj-$(CONFIG_TEST_DEBUG_VIRTUAL) += test_debug_virtual.o
+obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/ + ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG CFLAGS_kobject_uevent.o += -DDEBUG diff --git a/lib/livepatch/Makefile b/lib/livepatch/Makefile new file mode 100644 index 000000000000..26900ddaef82 --- /dev/null +++ b/lib/livepatch/Makefile @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for livepatch test code. + +obj-$(CONFIG_TEST_LIVEPATCH) += test_klp_atomic_replace.o \ + test_klp_callbacks_demo.o \ + test_klp_callbacks_demo2.o \ + test_klp_callbacks_busy.o \ + test_klp_callbacks_mod.o \ + test_klp_livepatch.o \ + test_klp_shadow_vars.o + +# Target modules to be livepatched require CC_FLAGS_FTRACE +CFLAGS_test_klp_callbacks_busy.o += $(CC_FLAGS_FTRACE) +CFLAGS_test_klp_callbacks_mod.o += $(CC_FLAGS_FTRACE) diff --git a/lib/livepatch/test_klp_atomic_replace.c b/lib/livepatch/test_klp_atomic_replace.c new file mode 100644 index 000000000000..d1bcf6b0cfb3 --- /dev/null +++ b/lib/livepatch/test_klp_atomic_replace.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> + +static int replace; +module_param(replace, int, 0644); +MODULE_PARM_DESC(replace, "replace (default=0)"); + +#include <linux/seq_file.h> +static int livepatch_meminfo_proc_show(struct seq_file *m, void *v) +{ + seq_printf(m, "%s: %s\n", THIS_MODULE->name, + "this has been live patched"); + return 0; +} + +static struct klp_func funcs[] = { + { + .old_name = "meminfo_proc_show", + .new_func = livepatch_meminfo_proc_show, + }, { } +}; + +static struct klp_object objs[] = { + { + /* name being NULL means vmlinux */ + .funcs = funcs, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, + /* set .replace in the init function below for demo purposes */ +}; + +static int test_klp_atomic_replace_init(void) +{ + int ret; + + patch.replace = replace; + + ret = klp_register_patch(&patch); + if (ret) + return ret; + ret = klp_enable_patch(&patch); + if (ret) { + WARN_ON(klp_unregister_patch(&patch)); + return ret; + } + return 0; +} + +static void test_klp_atomic_replace_exit(void) +{ + WARN_ON(klp_unregister_patch(&patch)); +} + +module_init(test_klp_atomic_replace_init); +module_exit(test_klp_atomic_replace_exit); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); +MODULE_AUTHOR("Joe Lawrence joe.lawrence@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: atomic replace"); diff --git a/lib/livepatch/test_klp_callbacks_busy.c b/lib/livepatch/test_klp_callbacks_busy.c new file mode 100644 index 000000000000..40beddf8a0e2 --- /dev/null +++ b/lib/livepatch/test_klp_callbacks_busy.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/workqueue.h> +#include <linux/delay.h> + +static int sleep_secs; +module_param(sleep_secs, int, 0644); +MODULE_PARM_DESC(sleep_secs, "sleep_secs (default=0)"); + +static void busymod_work_func(struct work_struct *work); +static DECLARE_DELAYED_WORK(work, busymod_work_func); + +static void busymod_work_func(struct work_struct *work) +{ + pr_info("%s, sleeping %d seconds ...\n", __func__, sleep_secs); + msleep(sleep_secs * 1000); + pr_info("%s exit\n", __func__); +} + +static int test_klp_callbacks_busy_init(void) +{ + pr_info("%s\n", __func__); + schedule_delayed_work(&work, + msecs_to_jiffies(1000 * 0)); + return 0; +} + +static void test_klp_callbacks_busy_exit(void) +{ + cancel_delayed_work_sync(&work); + pr_info("%s\n", __func__); +} + +module_init(test_klp_callbacks_busy_init); +module_exit(test_klp_callbacks_busy_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Joe Lawrence joe.lawrence@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: busy target module"); diff --git a/lib/livepatch/test_klp_callbacks_demo.c b/lib/livepatch/test_klp_callbacks_demo.c new file mode 100644 index 000000000000..87fc61445c5f --- /dev/null +++ b/lib/livepatch/test_klp_callbacks_demo.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> + +static int pre_patch_ret; +module_param(pre_patch_ret, int, 0644); +MODULE_PARM_DESC(pre_patch_ret, "pre_patch_ret (default=0)"); + +static const char *const module_state[] = { + [MODULE_STATE_LIVE] = "[MODULE_STATE_LIVE] Normal state", + [MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init", + [MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away", + [MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up", +}; + +static void callback_info(const char *callback, struct klp_object *obj) +{ + if (obj->mod) + pr_info("%s: %s -> %s\n", callback, obj->mod->name, + module_state[obj->mod->state]); + else + pr_info("%s: vmlinux\n", callback); +} + +/* Executed on object patching (ie, patch enablement) */ +static int pre_patch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); + return pre_patch_ret; +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void post_patch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void pre_unpatch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void post_unpatch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +static void patched_work_func(struct work_struct *work) +{ + pr_info("%s\n", __func__); +} + +static struct klp_func no_funcs[] = { + { } +}; + +static struct klp_func busymod_funcs[] = { + { + .old_name = "busymod_work_func", + .new_func = patched_work_func, + }, { } +}; + +static struct klp_object objs[] = { + { + .name = NULL, /* vmlinux */ + .funcs = no_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { + .name = "test_klp_callbacks_mod", + .funcs = no_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { + .name = "test_klp_callbacks_busy", + .funcs = busymod_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int test_klp_callbacks_demo_init(void) +{ + int ret; + + ret = klp_register_patch(&patch); + if (ret) + return ret; + ret = klp_enable_patch(&patch); + if (ret) { + WARN_ON(klp_unregister_patch(&patch)); + return ret; + } + return 0; +} + +static void test_klp_callbacks_demo_exit(void) +{ + WARN_ON(klp_unregister_patch(&patch)); +} + +module_init(test_klp_callbacks_demo_init); +module_exit(test_klp_callbacks_demo_exit); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); +MODULE_AUTHOR("Joe Lawrence joe.lawrence@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: livepatch demo"); diff --git a/lib/livepatch/test_klp_callbacks_demo2.c b/lib/livepatch/test_klp_callbacks_demo2.c new file mode 100644 index 000000000000..c2a6c7b40424 --- /dev/null +++ b/lib/livepatch/test_klp_callbacks_demo2.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> + +static int replace; +module_param(replace, int, 0644); +MODULE_PARM_DESC(replace, "replace (default=0)"); + +static const char *const module_state[] = { + [MODULE_STATE_LIVE] = "[MODULE_STATE_LIVE] Normal state", + [MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init", + [MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away", + [MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up", +}; + +static void callback_info(const char *callback, struct klp_object *obj) +{ + if (obj->mod) + pr_info("%s: %s -> %s\n", callback, obj->mod->name, + module_state[obj->mod->state]); + else + pr_info("%s: vmlinux\n", callback); +} + +/* Executed on object patching (ie, patch enablement) */ +static int pre_patch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); + return 0; +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void post_patch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void pre_unpatch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void post_unpatch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +static struct klp_func no_funcs[] = { + { } +}; + +static struct klp_object objs[] = { + { + .name = NULL, /* vmlinux */ + .funcs = no_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int test_klp_callbacks_demo2_init(void) +{ + int ret; + + patch.replace = replace; + + ret = klp_register_patch(&patch); + if (ret) + return ret; + ret = klp_enable_patch(&patch); + if (ret) { + WARN_ON(klp_unregister_patch(&patch)); + return ret; + } + return 0; +} + +static void test_klp_callbacks_demo2_exit(void) +{ + WARN_ON(klp_unregister_patch(&patch)); +} + +module_init(test_klp_callbacks_demo2_init); +module_exit(test_klp_callbacks_demo2_exit); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); +MODULE_AUTHOR("Joe Lawrence joe.lawrence@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: livepatch demo2"); diff --git a/lib/livepatch/test_klp_callbacks_mod.c b/lib/livepatch/test_klp_callbacks_mod.c new file mode 100644 index 000000000000..8fbe645b1c2c --- /dev/null +++ b/lib/livepatch/test_klp_callbacks_mod.c @@ -0,0 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> + +static int test_klp_callbacks_mod_init(void) +{ + pr_info("%s\n", __func__); + return 0; +} + +static void test_klp_callbacks_mod_exit(void) +{ + pr_info("%s\n", __func__); +} + +module_init(test_klp_callbacks_mod_init); +module_exit(test_klp_callbacks_mod_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Joe Lawrence joe.lawrence@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: target module"); diff --git a/lib/livepatch/test_klp_livepatch.c b/lib/livepatch/test_klp_livepatch.c new file mode 100644 index 000000000000..4014754c8da8 --- /dev/null +++ b/lib/livepatch/test_klp_livepatch.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2014 Seth Jennings sjenning@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> + +#include <linux/seq_file.h> +static int livepatch_cmdline_proc_show(struct seq_file *m, void *v) +{ + seq_printf(m, "%s: %s\n", THIS_MODULE->name, + "this has been live patched"); + return 0; +} + +static struct klp_func funcs[] = { + { + .old_name = "cmdline_proc_show", + .new_func = livepatch_cmdline_proc_show, + }, { } +}; + +static struct klp_object objs[] = { + { + /* name being NULL means vmlinux */ + .funcs = funcs, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int test_klp_livepatch_init(void) +{ + int ret; + + ret = klp_register_patch(&patch); + if (ret) + return ret; + ret = klp_enable_patch(&patch); + if (ret) { + WARN_ON(klp_unregister_patch(&patch)); + return ret; + } + return 0; +} + +static void test_klp_livepatch_exit(void) +{ + WARN_ON(klp_unregister_patch(&patch)); +} + +module_init(test_klp_livepatch_init); +module_exit(test_klp_livepatch_exit); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); +MODULE_AUTHOR("Seth Jennings sjenning@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: livepatch module"); diff --git a/lib/livepatch/test_klp_shadow_vars.c b/lib/livepatch/test_klp_shadow_vars.c new file mode 100644 index 000000000000..05f45747c081 --- /dev/null +++ b/lib/livepatch/test_klp_shadow_vars.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/livepatch.h> +#include <linux/slab.h> + +/* + * Keep a small list of pointers so that we can print address-agnostic + * pointer values. Use a rolling integer count to differentiate the values. + * Ironically we could have used the shadow variable API to do this, but + * let's not lean too heavily on the very code we're testing. + */ +static LIST_HEAD(ptr_list); +struct shadow_ptr { + void *ptr; + int id; + struct list_head list; +}; + +void free_ptr_list(void) +{ + struct shadow_ptr *sp, *tmp_sp; + + list_for_each_entry_safe(sp, tmp_sp, &ptr_list, list) { + list_del(&sp->list); + kfree(sp); + } +} + +int ptr_id(void *ptr) +{ + struct shadow_ptr *sp; + static int count; + + list_for_each_entry(sp, &ptr_list, list) { + if (sp->ptr == ptr) + return sp->id; + } + + sp = kmalloc(sizeof(*sp), GFP_KERNEL); + if (!sp) + return -1; + sp->ptr = ptr; + sp->id = count++; + + list_add(&sp->list, &ptr_list); + + return sp->id; +} + +/* + * Shadow variable wrapper functions that echo the function and arguments + * to the kernel log for testing verification. Don't display raw pointers, + * but use the ptr_id() value instead. + */ +void *shadow_get(void *obj, unsigned long id) +{ + void *ret = klp_shadow_get(obj, id); + + pr_info("klp_%s(obj=PTR%d, id=0x%lx) = PTR%d\n", + __func__, ptr_id(obj), id, ptr_id(ret)); + + return ret; +} + +void *shadow_alloc(void *obj, unsigned long id, size_t size, gfp_t gfp_flags, + klp_shadow_ctor_t ctor, void *ctor_data) +{ + void *ret = klp_shadow_alloc(obj, id, size, gfp_flags, ctor, + ctor_data); + pr_info("klp_%s(obj=PTR%d, id=0x%lx, size=%zx, gfp_flags=%pGg), ctor=PTR%d, ctor_data=PTR%d = PTR%d\n", + __func__, ptr_id(obj), id, size, &gfp_flags, ptr_id(ctor), + ptr_id(ctor_data), ptr_id(ret)); + return ret; +} + +void *shadow_get_or_alloc(void *obj, unsigned long id, size_t size, + gfp_t gfp_flags, klp_shadow_ctor_t ctor, + void *ctor_data) +{ + void *ret = klp_shadow_get_or_alloc(obj, id, size, gfp_flags, ctor, + ctor_data); + pr_info("klp_%s(obj=PTR%d, id=0x%lx, size=%zx, gfp_flags=%pGg), ctor=PTR%d, ctor_data=PTR%d = PTR%d\n", + __func__, ptr_id(obj), id, size, &gfp_flags, ptr_id(ctor), + ptr_id(ctor_data), ptr_id(ret)); + return ret; +} + +void shadow_free(void *obj, unsigned long id, klp_shadow_dtor_t dtor) +{ + klp_shadow_free(obj, id, dtor); + pr_info("klp_%s(obj=PTR%d, id=0x%lx, dtor=PTR%d)\n", + __func__, ptr_id(obj), id, ptr_id(dtor)); +} + +void shadow_free_all(unsigned long id, klp_shadow_dtor_t dtor) +{ + klp_shadow_free_all(id, dtor); + pr_info("klp_%s(id=0x%lx, dtor=PTR%d)\n", + __func__, id, ptr_id(dtor)); +} + + +/* Shadow variable constructor - remember simple pointer data */ +static int shadow_ctor(void *obj, void *shadow_data, void *ctor_data) +{ + int **shadow_int = shadow_data; + *shadow_int = ctor_data; + pr_info("%s: PTR%d -> PTR%d\n", + __func__, ptr_id(shadow_int), ptr_id(ctor_data)); + + return 0; +} + +static void shadow_dtor(void *obj, void *shadow_data) +{ + pr_info("%s(obj=PTR%d, shadow_data=PTR%d)\n", + __func__, ptr_id(obj), ptr_id(shadow_data)); +} + +static int test_klp_shadow_vars_init(void) +{ + void *obj = THIS_MODULE; + int id = 0x1234; + size_t size = sizeof(int *); + gfp_t gfp_flags = GFP_KERNEL; + + int var1, var2, var3, var4; + int **sv1, **sv2, **sv3, **sv4; + + void *ret; + + ptr_id(0); + ptr_id(&var1); + ptr_id(&var2); + ptr_id(&var3); + ptr_id(&var4); + + /* + * With an empty shadow variable hash table, expect not to find + * any matches. + */ + ret = shadow_get(obj, id); + if (!ret) + pr_info(" got expected NULL result\n"); + + /* + * Allocate a few shadow variables with different <obj> and <id>. + */ + sv1 = shadow_alloc(obj, id, size, gfp_flags, shadow_ctor, &var1); + sv2 = shadow_alloc(obj + 1, id, size, gfp_flags, shadow_ctor, &var2); + sv3 = shadow_alloc(obj, id + 1, size, gfp_flags, shadow_ctor, &var3); + + /* + * Verify we can find our new shadow variables and that they point + * to expected data. + */ + ret = shadow_get(obj, id); + if (ret == sv1 && *sv1 == &var1) + pr_info(" got expected PTR%d -> PTR%d result\n", + ptr_id(sv1), ptr_id(*sv1)); + ret = shadow_get(obj + 1, id); + if (ret == sv2 && *sv2 == &var2) + pr_info(" got expected PTR%d -> PTR%d result\n", + ptr_id(sv2), ptr_id(*sv2)); + ret = shadow_get(obj, id + 1); + if (ret == sv3 && *sv3 == &var3) + pr_info(" got expected PTR%d -> PTR%d result\n", + ptr_id(sv3), ptr_id(*sv3)); + + /* + * Allocate or get a few more, this time with the same <obj>, <id>. + * The second invocation should return the same shadow var. + */ + sv4 = shadow_get_or_alloc(obj + 2, id, size, gfp_flags, shadow_ctor, &var4); + ret = shadow_get_or_alloc(obj + 2, id, size, gfp_flags, shadow_ctor, &var4); + if (ret == sv4 && *sv4 == &var4) + pr_info(" got expected PTR%d -> PTR%d result\n", + ptr_id(sv4), ptr_id(*sv4)); + + /* + * Free the <obj=*, id> shadow variables and check that we can no + * longer find them. + */ + shadow_free(obj, id, shadow_dtor); /* sv1 */ + ret = shadow_get(obj, id); + if (!ret) + pr_info(" got expected NULL result\n"); + + shadow_free(obj + 1, id, shadow_dtor); /* sv2 */ + ret = shadow_get(obj + 1, id); + if (!ret) + pr_info(" got expected NULL result\n"); + + shadow_free(obj + 2, id, shadow_dtor); /* sv4 */ + ret = shadow_get(obj + 2, id); + if (!ret) + pr_info(" got expected NULL result\n"); + + /* + * We should still find an <id+1> variable. + */ + ret = shadow_get(obj, id + 1); + if (ret == sv3 && *sv3 == &var3) + pr_info(" got expected PTR%d -> PTR%d result\n", + ptr_id(sv3), ptr_id(*sv3)); + + /* + * Free all the <id+1> variables, too. + */ + shadow_free_all(id + 1, shadow_dtor); /* sv3 */ + ret = shadow_get(obj, id); + if (!ret) + pr_info(" shadow_get() got expected NULL result\n"); + + + free_ptr_list(); + + return 0; +} + +static void test_klp_shadow_vars_exit(void) +{ +} + +module_init(test_klp_shadow_vars_init); +module_init(test_klp_shadow_vars_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Joe Lawrence joe.lawrence@redhat.com"); +MODULE_DESCRIPTION("Livepatch test: shadow variables"); diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 7442dfb73b7f..d92c63bde9b6 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -15,6 +15,7 @@ TARGETS += intel_pstate TARGETS += ipc TARGETS += kcmp TARGETS += lib +TARGETS += livepatch TARGETS += membarrier TARGETS += memfd TARGETS += memory-hotplug diff --git a/tools/testing/selftests/livepatch/Makefile b/tools/testing/selftests/livepatch/Makefile new file mode 100644 index 000000000000..af4aee79bebb --- /dev/null +++ b/tools/testing/selftests/livepatch/Makefile @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0 + +TEST_GEN_PROGS := \ + test-livepatch.sh \ + test-callbacks.sh \ + test-shadow-vars.sh + +include ../lib.mk diff --git a/tools/testing/selftests/livepatch/config b/tools/testing/selftests/livepatch/config new file mode 100644 index 000000000000..0dd7700464a8 --- /dev/null +++ b/tools/testing/selftests/livepatch/config @@ -0,0 +1 @@ +CONFIG_TEST_LIVEPATCH=m diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh new file mode 100644 index 000000000000..7aaef80e9edb --- /dev/null +++ b/tools/testing/selftests/livepatch/functions.sh @@ -0,0 +1,196 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +# Shell functions for the rest of the scripts. + +MAX_RETRIES=600 +RETRY_INTERVAL=".1" # seconds + +# die(msg) - game over, man +# msg - dying words +function die() { + echo "ERROR: $1" >&2 + exit 1 +} + +# set_dynamic_debug() - setup kernel dynamic debug +# TODO - push and pop this config? +function set_dynamic_debug() { + cat << EOF > /sys/kernel/debug/dynamic_debug/control +file kernel/livepatch/* +p +func klp_try_switch_task -p +EOF +} + +# wait_for_transition(modname) +# modname - livepatch module name +wait_for_transition() { + local mod="$1"; shift + + # Wait for livepatch transition ... + local i=0 + while [[ $(cat /sys/kernel/livepatch/"$mod"/transition) != "0" ]]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to complete transition for module $mod" + fi + sleep $RETRY_INTERVAL + done +} + +# load_mod(modname, params) - load a kernel module +# modname - module name to load +# params - module parameters to pass to modprobe +function load_mod() { + local mod="$1"; shift + local args="$*" + + local msg="% modprobe $mod $args" + echo "${msg%% }" > /dev/kmsg + ret=$(modprobe "$mod" "$args" 2>&1) + if [[ "$ret" != "" ]]; then + echo "$ret" > /dev/kmsg + die "$ret" + fi + + # Wait for module in sysfs ... + local i=0 + while [ ! -e /sys/module/"$mod" ]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to load module $mod" + fi + sleep $RETRY_INTERVAL + done + + # Wait for livepatch ... + if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then + + # Wait for livepatch in sysfs ... + local i=0 + while [ ! -e /sys/kernel/livepatch/"$mod" ]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to load module $mod (sysfs)" + fi + sleep $RETRY_INTERVAL + done + fi +} + +# load_failing_mod(modname, params) - load a kernel module, expect to fail +# modname - module name to load +# params - module parameters to pass to modprobe +function load_failing_mod() { + local mod="$1"; shift + local args="$*" + + local msg="% modprobe $mod $args" + echo "${msg%% }" > /dev/kmsg + ret=$(modprobe "$mod" "$args" 2>&1) + if [[ "$ret" == "" ]]; then + echo "$mod unexpectedly loaded" > /dev/kmsg + die "$mod unexpectedly loaded" + fi + echo "$ret" > /dev/kmsg +} + +# unload_mod(modname) - unload a kernel module +# modname - module name to unload +function unload_mod() { + local mod="$1" + + # Wait for module reference count to clear ... + local i=0 + while [[ $(cat /sys/module/"$mod"/refcnt) != "0" ]]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to unload module $mod (refcnt)" + fi + sleep $RETRY_INTERVAL + done + + echo "% rmmod $mod" > /dev/kmsg + ret=$(rmmod "$mod" 2>&1) + if [[ "$ret" != "" ]]; then + echo "$ret" > /dev/kmsg + die "$ret" + fi + + # Wait for module in sysfs ... + local i=0 + while [ -e /sys/module/"$mod" ]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to unload module $mod (/sys/module)" + fi + sleep $RETRY_INTERVAL + done + + # Wait for livepatch sysfs if applicable ... + if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then + + local i=0 + while [ -e /sys/kernel/livepatch/"$mod" ]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to unload module $mod (/sys/livepatch)" + fi + sleep $RETRY_INTERVAL + done + fi +} + +# display_lp(modname) - disable a livepatch +# modname - module name to unload +function disable_lp() { + local mod="$1" + + echo "% echo 0 > /sys/kernel/livepatch/$mod/enabled" > /dev/kmsg + echo 0 > /sys/kernel/livepatch/"$mod"/enabled + + # Wait for livepatch enable to clear ... + local i=0 + while [[ $(cat /sys/kernel/livepatch/"$mod"/enabled) != "0" ]]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to disable livepatch $mod" + fi + sleep $RETRY_INTERVAL + done +} + +# set_pre_patch_ret(modname, pre_patch_ret) +# modname - module name to set +# pre_patch_ret - new pre_patch_ret value +function set_pre_patch_ret { + local mod="$1"; shift + local ret="$1" + + echo "% echo $1 > /sys/module/$mod/parameters/pre_patch_ret" > /dev/kmsg + echo "$1" > /sys/module/"$mod"/parameters/pre_patch_ret + + local i=0 + while [[ $(cat /sys/module/"$mod"/parameters/pre_patch_ret) != "$1" ]]; do + i=$((i+1)) + if [[ $i -eq $MAX_RETRIES ]]; then + die "failed to set pre_patch_ret parameter for $mod module" + fi + sleep $RETRY_INTERVAL + done +} + +# filter_dmesg() - print a filtered dmesg +# TODO - better filter, out of order msgs, etc? +function check_result { + local expect="$*" + local result=$(dmesg | grep -v 'tainting' | grep -e 'livepatch:' -e 'test_klp' | sed 's/^[[ 0-9.]*] //') + + if [[ "$expect" == "$result" ]] ; then + echo "ok" + else + echo -e "not ok\n\n$(diff -upr --label expected --label result <(echo "$expect") <(echo "$result"))\n" + die "livepatch kselftest(s) failed" + fi +} diff --git a/tools/testing/selftests/livepatch/test-callbacks.sh b/tools/testing/selftests/livepatch/test-callbacks.sh new file mode 100755 index 000000000000..739d09bb3cff --- /dev/null +++ b/tools/testing/selftests/livepatch/test-callbacks.sh @@ -0,0 +1,607 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +. functions.sh + +MOD_LIVEPATCH=test_klp_callbacks_demo +MOD_LIVEPATCH2=test_klp_callbacks_demo2 +MOD_TARGET=test_klp_callbacks_mod +MOD_TARGET_BUSY=test_klp_callbacks_busy + +set_dynamic_debug + + +# TEST: target module before livepatch +# +# Test a combination of loading a kernel module and a livepatch that +# patches a function in the first module. Load the target module +# before the livepatch module. Unload them in the same order. +# +# - On livepatch enable, before the livepatch transition starts, +# pre-patch callbacks are executed for vmlinux and $MOD_TARGET (those +# klp_objects currently loaded). After klp_objects are patched +# according to the klp_patch, their post-patch callbacks run and the +# transition completes. +# +# - Similarly, on livepatch disable, pre-patch callbacks run before the +# unpatching transition starts. klp_objects are reverted, post-patch +# callbacks execute and the transition completes. + +echo -n "TEST: target module before livepatch ... " +dmesg -C + +load_mod $MOD_TARGET +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +disable_lp $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH +unload_mod $MOD_TARGET + +check_result "% modprobe $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_init +% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit" + + +# TEST: module_coming notifier +# +# This test is similar to the previous test, but (un)load the livepatch +# module before the target kernel module. This tests the livepatch +# core's module_coming handler. +# +# - On livepatch enable, only pre/post-patch callbacks are executed for +# currently loaded klp_objects, in this case, vmlinux. +# +# - When a targeted module is subsequently loaded, only its +# pre/post-patch callbacks are executed. +# +# - On livepatch disable, all currently loaded klp_objects' (vmlinux and +# $MOD_TARGET) pre/post-unpatch callbacks are executed. + +echo -n "TEST: module_coming notifier ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +load_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH +unload_mod $MOD_TARGET + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% modprobe $MOD_TARGET +livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET' +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_TARGET: ${MOD_TARGET}_init +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit" + + +# TEST: module_going notifier +# +# Test loading the livepatch after a targeted kernel module, then unload +# the kernel module before disabling the livepatch. This tests the +# livepatch core's module_going handler. +# +# - First load a target module, then the livepatch. +# +# - When a target module is unloaded, the livepatch is only reverted +# from that klp_object ($MOD_TARGET). As such, only its pre and +# post-unpatch callbacks are executed when this occurs. +# +# - When the livepatch is disabled, pre and post-unpatch callbacks are +# run for the remaining klp_object, vmlinux. + +echo -n "TEST: module_going notifier ... " +dmesg -C + +load_mod $MOD_TARGET +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH + +check_result "% modprobe $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_init +% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit +$MOD_LIVEPATCH: pre_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +livepatch: reverting patch '$MOD_LIVEPATCH' on unloading module '$MOD_TARGET' +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + + +# TEST: module_coming and module_going notifiers +# +# This test is similar to the previous test, however the livepatch is +# loaded first. This tests the livepatch core's module_coming and +# module_going handlers. +# +# - First load the livepatch. +# +# - When a targeted kernel module is subsequently loaded, only its +# pre/post-patch callbacks are executed. +# +# - When the target module is unloaded, the livepatch is only reverted +# from the $MOD_TARGET klp_object. As such, only pre and +# post-unpatch callbacks are executed when this occurs. + +echo -n "TEST: module_coming and module_going notifiers ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +load_mod $MOD_TARGET +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% modprobe $MOD_TARGET +livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET' +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_TARGET: ${MOD_TARGET}_init +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit +$MOD_LIVEPATCH: pre_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +livepatch: reverting patch '$MOD_LIVEPATCH' on unloading module '$MOD_TARGET' +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + + +# TEST: target module not present +# +# A simple test of loading a livepatch without one of its patch target +# klp_objects ever loaded ($MOD_TARGET). +# +# - Load the livepatch. +# +# - As expected, only pre/post-(un)patch handlers are executed for +# vmlinux. + +echo -n "TEST: target module not present ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + + +# TEST: pre-patch callback -ENODEV +# +# Test a scenario where a vmlinux pre-patch callback returns a non-zero +# status (ie, failure). +# +# - First load a target module. +# +# - Load the livepatch module, setting its 'pre_patch_ret' value to -19 +# (-ENODEV). When its vmlinux pre-patch callback executes, this +# status code will propagate back to the module-loading subsystem. +# The result is that the insmod command refuses to load the livepatch +# module. + +echo -n "TEST: pre-patch callback -ENODEV ... " +dmesg -C + +load_mod $MOD_TARGET +load_failing_mod $MOD_LIVEPATCH pre_patch_ret=-19 +unload_mod $MOD_TARGET + +check_result "% modprobe $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_init +% modprobe $MOD_LIVEPATCH pre_patch_ret=-19 +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_LIVE] Normal state +livepatch: pre-patch callback failed for object '$MOD_TARGET' +livepatch: failed to enable patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': canceling patching transition, going to unpatch +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +livepatch: '$MOD_LIVEPATCH': unpatching complete +modprobe: ERROR: could not insert '$MOD_LIVEPATCH': No such device +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit" + + +# TEST: module_coming + pre-patch callback -ENODEV +# +# Similar to the previous test, setup a livepatch such that its vmlinux +# pre-patch callback returns success. However, when a targeted kernel +# module is later loaded, have the livepatch return a failing status +# code. +# +# - Load the livepatch, vmlinux pre-patch callback succeeds. +# +# - Set a trap so subsequent pre-patch callbacks to this livepatch will +# return -ENODEV. +# +# - The livepatch pre-patch callback for subsequently loaded target +# modules will return failure, so the module loader refuses to load +# the kernel module. No post-patch or pre/post-unpatch callbacks are +# executed for this klp_object. +# +# - Pre/post-unpatch callbacks are run for the vmlinux klp_object. + +echo -n "TEST: module_coming + pre-patch callback -ENODEV ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +set_pre_patch_ret $MOD_LIVEPATCH -19 +load_failing_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% echo -19 > /sys/module/$MOD_LIVEPATCH/parameters/pre_patch_ret +% modprobe $MOD_TARGET +livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET' +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +livepatch: pre-patch callback failed for object '$MOD_TARGET' +livepatch: patch '$MOD_LIVEPATCH' failed for module '$MOD_TARGET', refusing to load module '$MOD_TARGET' +modprobe: ERROR: could not insert '$MOD_TARGET': No such device +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + + +# TEST: multiple target modules +# +# Test loading multiple targeted kernel modules. This test-case is +# mainly for comparing with the next test-case. +# +# - Load a target "busy" kernel module which kicks off a worker function +# that immediately exits. +# +# - Proceed with loading the livepatch and another ordinary target +# module. Post-patch callbacks are executed and the transition +# completes quickly. + +echo -n "TEST: multiple target modules ... " +dmesg -C + +load_mod $MOD_TARGET_BUSY sleep_secs=0 +# give $MOD_TARGET_BUSY::busymod_work_func() a chance to run +sleep 5 +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +load_mod $MOD_TARGET +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH +unload_mod $MOD_TARGET_BUSY + +check_result "% modprobe $MOD_TARGET_BUSY sleep_secs=0 +$MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init +$MOD_TARGET_BUSY: busymod_work_func, sleeping 0 seconds ... +$MOD_TARGET_BUSY: busymod_work_func exit +% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% modprobe $MOD_TARGET +livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET' +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_LIVEPATCH: post_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_TARGET: ${MOD_TARGET}_init +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit +$MOD_LIVEPATCH: pre_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +livepatch: reverting patch '$MOD_LIVEPATCH' on unloading module '$MOD_TARGET' +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH +% rmmod $MOD_TARGET_BUSY +$MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_exit" + + + +# TEST: busy target module +# +# A similar test as the previous one, but force the "busy" kernel module +# to do longer work. +# +# The livepatching core will refuse to patch a task that is currently +# executing a to-be-patched function -- the consistency model stalls the +# current patch transition until this safety-check is met. Test a +# scenario where one of a livepatch's target klp_objects sits on such a +# function for a long time. Meanwhile, load and unload other target +# kernel modules while the livepatch transition is in progress. +# +# - Load the "busy" kernel module, this time make it do 10 seconds worth +# of work. +# +# - Meanwhile, the livepatch is loaded. Notice that the patch +# transition does not complete as the targeted "busy" module is +# sitting on a to-be-patched function. +# +# - Load a second target module (this one is an ordinary idle kernel +# module). Note that *no* post-patch callbacks will be executed while +# the livepatch is still in transition. +# +# - Request an unload of the simple kernel module. The patch is still +# transitioning, so its pre-unpatch callbacks are skipped. +# +# - Finally the livepatch is disabled. Since none of the patch's +# klp_object's post-patch callbacks executed, the remaining +# klp_object's pre-unpatch callbacks are skipped. + +echo -n "TEST: busy target module ... " +dmesg -C + +load_mod $MOD_TARGET_BUSY sleep_secs=10 +load_mod $MOD_LIVEPATCH +# Don't wait for transition, load $MOD_TARGET while the transition +# is still stalled in $MOD_TARGET_BUSY::busymod_work_func() +sleep 5 +load_mod $MOD_TARGET +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH +unload_mod $MOD_TARGET_BUSY + +check_result "% modprobe $MOD_TARGET_BUSY sleep_secs=10 +$MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init +$MOD_TARGET_BUSY: busymod_work_func, sleeping 10 seconds ... +% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +% modprobe $MOD_TARGET +livepatch: applying patch '$MOD_LIVEPATCH' to loading module '$MOD_TARGET' +$MOD_LIVEPATCH: pre_patch_callback: $MOD_TARGET -> [MODULE_STATE_COMING] Full formed, running module_init +$MOD_TARGET: ${MOD_TARGET}_init +% rmmod $MOD_TARGET +$MOD_TARGET: ${MOD_TARGET}_exit +livepatch: reverting patch '$MOD_LIVEPATCH' on unloading module '$MOD_TARGET' +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET -> [MODULE_STATE_GOING] Going away +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': reversing transition from patching to unpatching +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: $MOD_TARGET_BUSY -> [MODULE_STATE_LIVE] Normal state +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH +% rmmod $MOD_TARGET_BUSY +$MOD_TARGET_BUSY: busymod_work_func exit +$MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_exit" + + +# TEST: multiple livepatches +# +# Test loading multiple livepatches. This test-case is mainly for comparing +# with the next test-case. +# +# - Load and unload two livepatches, pre and post (un)patch callbacks +# execute as each patch progresses through its (un)patching +# transition. + +echo -n "TEST: multiple livepatches ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +load_mod $MOD_LIVEPATCH2 +wait_for_transition $MOD_LIVEPATCH2 +disable_lp $MOD_LIVEPATCH2 +wait_for_transition $MOD_LIVEPATCH2 +disable_lp $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH2 +unload_mod $MOD_LIVEPATCH + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% modprobe $MOD_LIVEPATCH2 +livepatch: enabling patch '$MOD_LIVEPATCH2' +livepatch: '$MOD_LIVEPATCH2': initializing patching transition +$MOD_LIVEPATCH2: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': starting patching transition +livepatch: '$MOD_LIVEPATCH2': completing patching transition +$MOD_LIVEPATCH2: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH2/enabled +livepatch: '$MOD_LIVEPATCH2': initializing unpatching transition +$MOD_LIVEPATCH2: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': starting unpatching transition +livepatch: '$MOD_LIVEPATCH2': completing unpatching transition +$MOD_LIVEPATCH2: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': unpatching complete +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +$MOD_LIVEPATCH: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +$MOD_LIVEPATCH: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH2 +% rmmod $MOD_LIVEPATCH" + + +# TEST: atomic replace +# +# Load multiple livepatches, but the second as an 'atomic-replace' +# patch. When the latter laods, the original livepatch should be +# disabled and *none* of its pre/post-unpatch callbacks executed. On +# the other hand, when the atomic-replace livepatch is disabled, its +# pre/post-unpatch callbacks *should* be executed. +# +# - Load and unload two livepatches, the second of which has its +# .replace flag set true. +# +# - Pre and post patch callbacks are executed for both livepatches. +# +# - Once the atomic replace module is loaded, only its pre and post +# unpatch callbacks are executed. + +echo -n "TEST: atomic replace ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH +load_mod $MOD_LIVEPATCH2 replace=1 +wait_for_transition $MOD_LIVEPATCH2 +disable_lp $MOD_LIVEPATCH2 +wait_for_transition $MOD_LIVEPATCH2 +unload_mod $MOD_LIVEPATCH2 +unload_mod $MOD_LIVEPATCH + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +$MOD_LIVEPATCH: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +$MOD_LIVEPATCH: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH': patching complete +% modprobe $MOD_LIVEPATCH2 replace=1 +livepatch: enabling patch '$MOD_LIVEPATCH2' +livepatch: '$MOD_LIVEPATCH2': initializing patching transition +$MOD_LIVEPATCH2: pre_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': starting patching transition +livepatch: '$MOD_LIVEPATCH2': completing patching transition +$MOD_LIVEPATCH2: post_patch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH2/enabled +livepatch: '$MOD_LIVEPATCH2': initializing unpatching transition +$MOD_LIVEPATCH2: pre_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': starting unpatching transition +livepatch: '$MOD_LIVEPATCH2': completing unpatching transition +$MOD_LIVEPATCH2: post_unpatch_callback: vmlinux +livepatch: '$MOD_LIVEPATCH2': unpatching complete +% rmmod $MOD_LIVEPATCH2 +% rmmod $MOD_LIVEPATCH" + + +exit 0 diff --git a/tools/testing/selftests/livepatch/test-livepatch.sh b/tools/testing/selftests/livepatch/test-livepatch.sh new file mode 100755 index 000000000000..3e4b8072da84 --- /dev/null +++ b/tools/testing/selftests/livepatch/test-livepatch.sh @@ -0,0 +1,173 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +. functions.sh + +MOD_LIVEPATCH=test_klp_livepatch +MOD_REPLACE=test_klp_atomic_replace + +set_dynamic_debug + + +# TEST: basic function patching +# - load a livepatch that modifies the output from /proc/cmdline and +# verify correct behavior +# - unload the livepatch and make sure the patch was removed + +echo -n "TEST: basic function patching ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH + +if [[ "$(cat /proc/cmdline)" != "$MOD_LIVEPATCH: this has been live patched" ]] ; then + echo -e "FAIL\n\n" + die "livepatch kselftest(s) failed" +fi + +disable_lp $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH + +if [[ "$(cat /proc/cmdline)" == "$MOD_LIVEPATCH: this has been live patched" ]] ; then + echo -e "FAIL\n\n" + die "livepatch kselftest(s) failed" +fi + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +livepatch: '$MOD_LIVEPATCH': patching complete +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + + +# TEST: multiple livepatches +# - load a livepatch that modifies the output from /proc/cmdline and +# verify correct behavior +# - load another livepatch and verify that both livepatches are active +# - unload the second livepatch and verify that the first is still active +# - unload the first livepatch and verify none are active + +echo -n "TEST: multiple livepatches ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +load_mod $MOD_REPLACE replace=0 +wait_for_transition $MOD_REPLACE + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +disable_lp $MOD_REPLACE +unload_mod $MOD_REPLACE + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +disable_lp $MOD_LIVEPATCH +unload_mod $MOD_LIVEPATCH + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +livepatch: '$MOD_LIVEPATCH': patching complete +$MOD_LIVEPATCH: this has been live patched +% modprobe $MOD_REPLACE replace=0 +livepatch: enabling patch '$MOD_REPLACE' +livepatch: '$MOD_REPLACE': initializing patching transition +livepatch: '$MOD_REPLACE': starting patching transition +livepatch: '$MOD_REPLACE': completing patching transition +livepatch: '$MOD_REPLACE': patching complete +$MOD_LIVEPATCH: this has been live patched +$MOD_REPLACE: this has been live patched +% echo 0 > /sys/kernel/livepatch/$MOD_REPLACE/enabled +livepatch: '$MOD_REPLACE': initializing unpatching transition +livepatch: '$MOD_REPLACE': starting unpatching transition +livepatch: '$MOD_REPLACE': completing unpatching transition +livepatch: '$MOD_REPLACE': unpatching complete +% rmmod $MOD_REPLACE +$MOD_LIVEPATCH: this has been live patched +% echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled +livepatch: '$MOD_LIVEPATCH': initializing unpatching transition +livepatch: '$MOD_LIVEPATCH': starting unpatching transition +livepatch: '$MOD_LIVEPATCH': completing unpatching transition +livepatch: '$MOD_LIVEPATCH': unpatching complete +% rmmod $MOD_LIVEPATCH" + + +# TEST: atomic replace livepatch +# - load a livepatch that modifies the output from /proc/cmdline and +# verify correct behavior +# - load an atomic replace livepatch and verify that only the second is active +# - remove the first livepatch and verify that the atomic replace livepatch +# is still active +# - remove the atomic replace livepatch and verify that none are active + +echo -n "TEST: atomic replace livepatch ... " +dmesg -C + +load_mod $MOD_LIVEPATCH +wait_for_transition $MOD_LIVEPATCH + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +load_mod $MOD_REPLACE replace=1 +wait_for_transition $MOD_REPLACE + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +unload_mod $MOD_LIVEPATCH + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +disable_lp $MOD_REPLACE +unload_mod $MOD_REPLACE + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +check_result "% modprobe $MOD_LIVEPATCH +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +livepatch: '$MOD_LIVEPATCH': patching complete +$MOD_LIVEPATCH: this has been live patched +% modprobe $MOD_REPLACE replace=1 +livepatch: enabling patch '$MOD_REPLACE' +livepatch: '$MOD_REPLACE': initializing patching transition +livepatch: '$MOD_REPLACE': starting patching transition +livepatch: '$MOD_REPLACE': completing patching transition +livepatch: '$MOD_REPLACE': patching complete +$MOD_REPLACE: this has been live patched +% rmmod $MOD_LIVEPATCH +$MOD_REPLACE: this has been live patched +% echo 0 > /sys/kernel/livepatch/$MOD_REPLACE/enabled +livepatch: '$MOD_REPLACE': initializing unpatching transition +livepatch: '$MOD_REPLACE': starting unpatching transition +livepatch: '$MOD_REPLACE': completing unpatching transition +livepatch: '$MOD_REPLACE': unpatching complete +% rmmod $MOD_REPLACE" + + +exit 0 diff --git a/tools/testing/selftests/livepatch/test-shadow-vars.sh b/tools/testing/selftests/livepatch/test-shadow-vars.sh new file mode 100755 index 000000000000..96390a21b15d --- /dev/null +++ b/tools/testing/selftests/livepatch/test-shadow-vars.sh @@ -0,0 +1,60 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2018 Joe Lawrence joe.lawrence@redhat.com + +. functions.sh + +MOD_TEST=test_klp_shadow_vars + +set_dynamic_debug + + +# TEST: basic shadow variable API +# - load a module that exercises the shadow variable API + +echo -n "TEST: basic shadow variable API ... " +dmesg -C + +load_mod $MOD_TEST +unload_mod $MOD_TEST + +check_result "% modprobe $MOD_TEST +$MOD_TEST: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 +$MOD_TEST: got expected NULL result +$MOD_TEST: shadow_ctor: PTR6 -> PTR1 +$MOD_TEST: klp_shadow_alloc(obj=PTR5, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR1 = PTR6 +$MOD_TEST: shadow_ctor: PTR8 -> PTR2 +$MOD_TEST: klp_shadow_alloc(obj=PTR9, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR2 = PTR8 +$MOD_TEST: shadow_ctor: PTR10 -> PTR3 +$MOD_TEST: klp_shadow_alloc(obj=PTR5, id=0x1235, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR3 = PTR10 +$MOD_TEST: klp_shadow_get(obj=PTR5, id=0x1234) = PTR6 +$MOD_TEST: got expected PTR6 -> PTR1 result +$MOD_TEST: klp_shadow_get(obj=PTR9, id=0x1234) = PTR8 +$MOD_TEST: got expected PTR8 -> PTR2 result +$MOD_TEST: klp_shadow_get(obj=PTR5, id=0x1235) = PTR10 +$MOD_TEST: got expected PTR10 -> PTR3 result +$MOD_TEST: shadow_ctor: PTR11 -> PTR4 +$MOD_TEST: klp_shadow_get_or_alloc(obj=PTR12, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR4 = PTR11 +$MOD_TEST: klp_shadow_get_or_alloc(obj=PTR12, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR4 = PTR11 +$MOD_TEST: got expected PTR11 -> PTR4 result +$MOD_TEST: shadow_dtor(obj=PTR5, shadow_data=PTR6) +$MOD_TEST: klp_shadow_free(obj=PTR5, id=0x1234, dtor=PTR13) +$MOD_TEST: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 +$MOD_TEST: got expected NULL result +$MOD_TEST: shadow_dtor(obj=PTR9, shadow_data=PTR8) +$MOD_TEST: klp_shadow_free(obj=PTR9, id=0x1234, dtor=PTR13) +$MOD_TEST: klp_shadow_get(obj=PTR9, id=0x1234) = PTR0 +$MOD_TEST: got expected NULL result +$MOD_TEST: shadow_dtor(obj=PTR12, shadow_data=PTR11) +$MOD_TEST: klp_shadow_free(obj=PTR12, id=0x1234, dtor=PTR13) +$MOD_TEST: klp_shadow_get(obj=PTR12, id=0x1234) = PTR0 +$MOD_TEST: got expected NULL result +$MOD_TEST: klp_shadow_get(obj=PTR5, id=0x1235) = PTR10 +$MOD_TEST: got expected PTR10 -> PTR3 result +$MOD_TEST: shadow_dtor(obj=PTR5, shadow_data=PTR10) +$MOD_TEST: klp_shadow_free_all(id=0x1235, dtor=PTR13) +$MOD_TEST: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 +$MOD_TEST: shadow_get() got expected NULL result +% rmmod test_klp_shadow_vars" + +exit 0
On Tue, Apr 10, 2018 at 11:15:54AM -0400, Joe Lawrence wrote:
+static void test_klp_shadow_vars_exit(void) +{ +}
+module_init(test_klp_shadow_vars_init); +module_init(test_klp_shadow_vars_exit);
For this last line, s/module_init/module_exit/, though I think the exit function can just be removed altogether?
Also I get the following bug (run on latest Linus master + Petr's two patch sets):
[ 106.302072] % modprobe test_klp_shadow_vars [ 106.311165] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 [ 106.313080] test_klp_shadow_vars: got expected NULL result [ 106.314811] BUG: sleeping function called from invalid context at mm/slab.h:421 [ 106.316518] in_atomic(): 1, irqs_disabled(): 1, pid: 2254, name: modprobe [ 106.318107] 1 lock held by modprobe/2254: [ 106.319332] #0: 00000000d0851080 (klp_shadow_lock){....}, at: __klp_shadow_get_or_alloc+0x88/0x1b0 [ 106.321220] irq event stamp: 4408 [ 106.322176] hardirqs last enabled at (4407): [<ffffffff8114c28e>] console_unlock+0x44e/0x680 [ 106.323598] hardirqs last disabled at (4408): [<ffffffff8199e6c7>] _raw_spin_lock_irqsave+0x27/0x90 [ 106.325041] softirqs last enabled at (4404): [<ffffffff81c0039b>] __do_softirq+0x39b/0x4fc [ 106.326469] softirqs last disabled at (4367): [<ffffffff810d8450>] irq_exit+0xe0/0xf0 [ 106.327901] Preemption disabled at: [ 106.327905] [<ffffffff81167c28>] __klp_shadow_get_or_alloc+0x88/0x1b0 [ 106.330117] CPU: 7 PID: 2254 Comm: modprobe Tainted: G K 4.16.0+ #60 [ 106.331565] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014 [ 106.333143] Call Trace: [ 106.334011] dump_stack+0x8e/0xd5 [ 106.334962] ___might_sleep+0x185/0x260 [ 106.335997] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars] [ 106.337170] __might_sleep+0x4a/0x80 [ 106.338137] kmem_cache_alloc_trace+0x20b/0x300 [ 106.339183] ? ptr_id+0x5c/0xd0 [test_klp_shadow_vars] [ 106.340341] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars] [ 106.341506] ptr_id+0x5c/0xd0 [test_klp_shadow_vars] [ 106.342725] shadow_ctor+0x20/0x40 [test_klp_shadow_vars] [ 106.343998] __klp_shadow_get_or_alloc+0xc4/0x1b0 [ 106.345184] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars] [ 106.346494] klp_shadow_alloc+0x10/0x20 [ 106.347583] shadow_alloc+0x28/0xa0 [test_klp_shadow_vars] [ 106.348871] ? shadow_free_all+0x40/0x40 [test_klp_shadow_vars] [ 106.350200] test_klp_shadow_vars_init+0x96/0x400 [test_klp_shadow_vars] [ 106.351646] ? shadow_free_all+0x40/0x40 [test_klp_shadow_vars] [ 106.352949] do_one_initcall+0x61/0x37f [ 106.353963] ? rcu_read_lock_sched_held+0x79/0x80 [ 106.355040] ? kmem_cache_alloc_trace+0x29d/0x300 [ 106.356098] ? do_init_module+0x27/0x213 [ 106.357090] do_init_module+0x5f/0x213 [ 106.358047] load_module+0x2815/0x2e70 [ 106.358992] ? vfs_read+0x12d/0x150 [ 106.359920] SYSC_finit_module+0xfc/0x120 [ 106.360870] ? SYSC_finit_module+0xfc/0x120 [ 106.361839] SyS_finit_module+0xe/0x10 [ 106.362753] do_syscall_64+0x7e/0x240 [ 106.363645] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 106.364711] RIP: 0033:0x7f26d0d40b19 [ 106.365799] RSP: 002b:00007ffee1de19a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 106.367306] RAX: ffffffffffffffda RBX: 00005636550d54b0 RCX: 00007f26d0d40b19 [ 106.368573] RDX: 0000000000000000 RSI: 0000563654134186 RDI: 0000000000000003 [ 106.369950] RBP: 0000563654134186 R08: 0000000000000000 R09: 00005636550d4270 [ 106.371164] R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 [ 106.372422] R13: 00005636550d53b0 R14: 0000000000040000 R15: 00005636550d54b0 [ 106.373900] test_klp_shadow_vars: shadow_ctor: PTR6 -> PTR1 [ 106.375249] test_klp_shadow_vars: klp_shadow_alloc(obj=PTR5, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR1 = PTR6 [ 106.378893] test_klp_shadow_vars: shadow_ctor: PTR8 -> PTR2 [ 106.380305] test_klp_shadow_vars: klp_shadow_alloc(obj=PTR9, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR2 = PTR8 [ 106.382779] test_klp_shadow_vars: shadow_ctor: PTR10 -> PTR3 [ 106.384131] test_klp_shadow_vars: klp_shadow_alloc(obj=PTR5, id=0x1235, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR3 = PTR10 [ 106.386584] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR6 [ 106.387929] test_klp_shadow_vars: got expected PTR6 -> PTR1 result [ 106.389181] test_klp_shadow_vars: klp_shadow_get(obj=PTR9, id=0x1234) = PTR8 [ 106.390488] test_klp_shadow_vars: got expected PTR8 -> PTR2 result [ 106.391731] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1235) = PTR10 [ 106.393066] test_klp_shadow_vars: got expected PTR10 -> PTR3 result [ 106.394347] test_klp_shadow_vars: shadow_ctor: PTR11 -> PTR4 [ 106.395523] test_klp_shadow_vars: klp_shadow_get_or_alloc(obj=PTR12, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR4 = PTR11 [ 106.398033] test_klp_shadow_vars: klp_shadow_get_or_alloc(obj=PTR12, id=0x1234, size=8, gfp_flags=GFP_KERNEL), ctor=PTR7, ctor_data=PTR4 = PTR11 [ 106.400554] test_klp_shadow_vars: got expected PTR11 -> PTR4 result [ 106.401937] test_klp_shadow_vars: shadow_dtor(obj=PTR5, shadow_data=PTR6) [ 106.403592] test_klp_shadow_vars: klp_shadow_free(obj=PTR5, id=0x1234, dtor=PTR13) [ 106.405083] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 [ 106.406500] test_klp_shadow_vars: got expected NULL result [ 106.407735] test_klp_shadow_vars: shadow_dtor(obj=PTR9, shadow_data=PTR8) [ 106.409252] test_klp_shadow_vars: klp_shadow_free(obj=PTR9, id=0x1234, dtor=PTR13) [ 106.410867] test_klp_shadow_vars: klp_shadow_get(obj=PTR9, id=0x1234) = PTR0 [ 106.412232] test_klp_shadow_vars: got expected NULL result [ 106.413461] test_klp_shadow_vars: shadow_dtor(obj=PTR12, shadow_data=PTR11) [ 106.414888] test_klp_shadow_vars: klp_shadow_free(obj=PTR12, id=0x1234, dtor=PTR13) [ 106.416319] test_klp_shadow_vars: klp_shadow_get(obj=PTR12, id=0x1234) = PTR0 [ 106.417681] test_klp_shadow_vars: got expected NULL result [ 106.418947] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1235) = PTR10 [ 106.420314] test_klp_shadow_vars: got expected PTR10 -> PTR3 result [ 106.421658] test_klp_shadow_vars: shadow_dtor(obj=PTR5, shadow_data=PTR10) [ 106.423065] test_klp_shadow_vars: klp_shadow_free_all(id=0x1235, dtor=PTR13) [ 106.424421] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 [ 106.425745] test_klp_shadow_vars: shadow_get() got expected NULL result [ 106.438719] % rmmod test_klp_shadow_vars
On 04/10/2018 04:00 PM, Josh Poimboeuf wrote:
On Tue, Apr 10, 2018 at 11:15:54AM -0400, Joe Lawrence wrote:
+static void test_klp_shadow_vars_exit(void) +{ +}
+module_init(test_klp_shadow_vars_init); +module_init(test_klp_shadow_vars_exit);
For this last line, s/module_init/module_exit/, though I think the exit function can just be removed altogether?
D'oh workspace / git user error, I posted an older version :(
But the exit function seems to be required if an init function is provided. Here I omitted the exit function:
% modprobe test_klp_shadow_vars % lsmod | grep test_klp_shadow_vars test_klp_shadow_vars 16384 0 % rmmod test_klp_shadow_vars rmmod: ERROR: could not remove 'test_klp_shadow_vars': Device or resource busy rmmod: ERROR: could not remove module test_klp_shadow_vars: Device or resource busy
and from kernel/module.c
SYSCALL_DEFINE2(delete_module, const char __user *, name_user, unsigned int, flags) ... /* If it has an init func, it must have an exit func to unload*/ if (mod->init && !mod->exit) { forced = try_force_unload(flags); if (!forced) { /* This module can't be removed */ ret = -EBUSY; goto out; } } ...
Also I get the following bug (run on latest Linus master + Petr's two patch sets):
[ 106.302072] % modprobe test_klp_shadow_vars [ 106.311165] test_klp_shadow_vars: klp_shadow_get(obj=PTR5, id=0x1234) = PTR0 [ 106.313080] test_klp_shadow_vars: got expected NULL result [ 106.314811] BUG: sleeping function called from invalid context at mm/slab.h:421 [ 106.316518] in_atomic(): 1, irqs_disabled(): 1, pid: 2254, name: modprobe [ 106.318107] 1 lock held by modprobe/2254: [ 106.319332] #0: 00000000d0851080 (klp_shadow_lock){....}, at: __klp_shadow_get_or_alloc+0x88/0x1b0 [ 106.321220] irq event stamp: 4408 [ 106.322176] hardirqs last enabled at (4407): [<ffffffff8114c28e>] console_unlock+0x44e/0x680 [ 106.323598] hardirqs last disabled at (4408): [<ffffffff8199e6c7>] _raw_spin_lock_irqsave+0x27/0x90 [ 106.325041] softirqs last enabled at (4404): [<ffffffff81c0039b>] __do_softirq+0x39b/0x4fc [ 106.326469] softirqs last disabled at (4367): [<ffffffff810d8450>] irq_exit+0xe0/0xf0 [ 106.327901] Preemption disabled at: [ 106.327905] [<ffffffff81167c28>] __klp_shadow_get_or_alloc+0x88/0x1b0 [ 106.330117] CPU: 7 PID: 2254 Comm: modprobe Tainted: G K 4.16.0+ #60 [ 106.331565] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014 [ 106.333143] Call Trace: [ 106.334011] dump_stack+0x8e/0xd5 [ 106.334962] ___might_sleep+0x185/0x260 [ 106.335997] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars] [ 106.337170] __might_sleep+0x4a/0x80 [ 106.338137] kmem_cache_alloc_trace+0x20b/0x300 [ 106.339183] ? ptr_id+0x5c/0xd0 [test_klp_shadow_vars] [ 106.340341] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars] [ 106.341506] ptr_id+0x5c/0xd0 [test_klp_shadow_vars] [ 106.342725] shadow_ctor+0x20/0x40 [test_klp_shadow_vars] [ 106.343998] __klp_shadow_get_or_alloc+0xc4/0x1b0 [ 106.345184] ? shadow_dtor+0x40/0x40 [test_klp_shadow_vars] [ 106.346494] klp_shadow_alloc+0x10/0x20 [ 106.347583] shadow_alloc+0x28/0xa0 [test_klp_shadow_vars] [ 106.348871] ? shadow_free_all+0x40/0x40 [test_klp_shadow_vars] [ 106.350200] test_klp_shadow_vars_init+0x96/0x400 [test_klp_shadow_vars] [ 106.351646] ? shadow_free_all+0x40/0x40 [test_klp_shadow_vars] [ 106.352949] do_one_initcall+0x61/0x37f [ 106.353963] ? rcu_read_lock_sched_held+0x79/0x80 [ 106.355040] ? kmem_cache_alloc_trace+0x29d/0x300 [ 106.356098] ? do_init_module+0x27/0x213 [ 106.357090] do_init_module+0x5f/0x213 [ 106.358047] load_module+0x2815/0x2e70 [ 106.358992] ? vfs_read+0x12d/0x150 [ 106.359920] SYSC_finit_module+0xfc/0x120 [ 106.360870] ? SYSC_finit_module+0xfc/0x120 [ 106.361839] SyS_finit_module+0xe/0x10 [ 106.362753] do_syscall_64+0x7e/0x240 [ 106.363645] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 106.364711] RIP: 0033:0x7f26d0d40b19 [ 106.365799] RSP: 002b:00007ffee1de19a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 106.367306] RAX: ffffffffffffffda RBX: 00005636550d54b0 RCX: 00007f26d0d40b19 [ 106.368573] RDX: 0000000000000000 RSI: 0000563654134186 RDI: 0000000000000003 [ 106.369950] RBP: 0000563654134186 R08: 0000000000000000 R09: 00005636550d4270 [ 106.371164] R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 [ 106.372422] R13: 00005636550d53b0 R14: 0000000000040000 R15: 00005636550d54b0
I missed Petr's commit msg note "that the constructor is called under klp_shadow_lock." I'll convert the test to use GFP_ATOMIC for this allocation.
I'll also add CONFIG_PM_SLEEP_DEBUG=y to my test VM kernel .config. Any other debug option suggestions?
-- Joe -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Apr 10, 2018 at 04:50:51PM -0400, Joe Lawrence wrote:
On 04/10/2018 04:00 PM, Josh Poimboeuf wrote:
On Tue, Apr 10, 2018 at 11:15:54AM -0400, Joe Lawrence wrote:
+static void test_klp_shadow_vars_exit(void) +{ +}
+module_init(test_klp_shadow_vars_init); +module_init(test_klp_shadow_vars_exit);
For this last line, s/module_init/module_exit/, though I think the exit function can just be removed altogether?
D'oh workspace / git user error, I posted an older version :(
But the exit function seems to be required if an init function is provided. Here I omitted the exit function:
% modprobe test_klp_shadow_vars % lsmod | grep test_klp_shadow_vars test_klp_shadow_vars 16384 0 % rmmod test_klp_shadow_vars rmmod: ERROR: could not remove 'test_klp_shadow_vars': Device or resource busy rmmod: ERROR: could not remove module test_klp_shadow_vars: Device or resource busy
and from kernel/module.c
SYSCALL_DEFINE2(delete_module, const char __user *, name_user, unsigned int, flags) ... /* If it has an init func, it must have an exit func to unload*/ if (mod->init && !mod->exit) { forced = try_force_unload(flags); if (!forced) { /* This module can't be removed */ ret = -EBUSY; goto out; } } ...
Hm, ok, though that seems like a weird limitation...
I missed Petr's commit msg note "that the constructor is called under klp_shadow_lock." I'll convert the test to use GFP_ATOMIC for this allocation.
I'll also add CONFIG_PM_SLEEP_DEBUG=y to my test VM kernel .config. Any other debug option suggestions?
I think CONFIG_LOCKDEP is always a good idea. Otherwise, I dunno... Here's my .config:
https://paste.fedoraproject.org/paste/cnM-J18uVWJrxz2DAdSchg
On Tue, 10 Apr 2018, Josh Poimboeuf wrote:
I think CONFIG_LOCKDEP is always a good idea.
FWIW CONFIG_LOCKDEP mostly enables the infrastructure, but CONFIG_PROVE_LOCKING is what turns most of the cleverness on.
On Tue, Apr 10, 2018 at 11:15:53AM -0400, Joe Lawrence wrote:
Questions for v3:
- Should we split off the atomic replace and shadow variable update tests so that the this patchset could be merged before the ones listed above?
Don't split it up on my account. We can just merge this one shortly after.
Questions for v3:
- Should we split off the atomic replace and shadow variable update tests so that the this patchset could be merged before the ones listed above?
What Josh said. If we merge it almost together, there is no need to split it.
- I didn't remove any of the sample modules. If anyone thinks any of them should go, let me know. They serve as nice, simple examples so I thought they should all stay.
Ok
- Module naming convention: to make the test script easier to grep module names and filenames, I broke with livepatch convention and used underscores instead of dashes. I didn't think it worth the regex foo to flip back and forth in the test script.
Ok
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