This round incorporates feedback from SUSE folks, Miroslav, Petr and Libor. Thanks for the reviews and feedback!
Like the previous version, this applies on top of Petr's shadow variable changes and the atomic replace patchset.
-- Joe
changes from v3: - add MAINTAINERS entry for tools/testing/selftests/livepatch/ - make more test_klp_shadow_vars.c functions static (Miroslav) - use git format-patch --base to generate base-commit and prerequisite patch info (kbuild test robot) - tweak TEST_LIVEPATCH help text (Petr) - add note in callbacks.txt pointing to sample/test examples (Petr) - add a kmsg log() function (Libor) - various whitespace and comment cleanups (Libor) - add "$(dirname $0)/" directory prefix to functions.sh sourcing (Libor) - add loop_until() function instead of redundant inline retry/loops (Libor) - wait_for_transition() looks for any transition (Libor)
changes from v2: - fix module_exit(test_klp_shadow_vars_exit) in test_klp_shadow_vars.c - silence kbuild test robot's "XXX can be static" and "Using plain integer as NULL pointer" complaints - re-run tests with CONFIG_LOCKDEP=y and CONFIG_PROVE_LOCKING=y - use GFP_ATOMIC in test_klp_shadow_vars.c constructor code
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
changes 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 | 489 +------------- MAINTAINERS | 1 + lib/Kconfig.debug | 21 + 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 | 236 +++++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/livepatch/Makefile | 8 + tools/testing/selftests/livepatch/README | 43 ++ tools/testing/selftests/livepatch/config | 1 + .../testing/selftests/livepatch/functions.sh | 164 +++++ .../selftests/livepatch/test-callbacks.sh | 607 ++++++++++++++++++ .../selftests/livepatch/test-livepatch.sh | 173 +++++ .../selftests/livepatch/test-shadow-vars.sh | 60 ++ 20 files changed, 1771 insertions(+), 484 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/README 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
base-commit: 0adb32858b0bddf4ada5f364a84ed60b196dbcda prerequisite-patch-id: 5ed747c1a89a5dc4bba08186e21f927d7f3bf049 prerequisite-patch-id: e9800288b71a9f339ea066e58d9ef70dece67083 prerequisite-patch-id: 415f2e190b1b50142c78f2940c7b8dd39b5321a0 prerequisite-patch-id: d229d9cf08af087e0a758d9df1da467103c2c200 prerequisite-patch-id: b8c7ef99b13c6b321cba5e8919ed0b3e29f213e9 prerequisite-patch-id: 4e10c0d08f151b18310fe0b1e5013d62db94cfeb prerequisite-patch-id: 33046b190c114d202f3a52e0e274dbb2b1907a4c prerequisite-patch-id: 6978944a725756317dd4e005d479b6101784aaf0 prerequisite-patch-id: cce9d3c7e1ae8887f387ca9e072552dc63479749 prerequisite-patch-id: c44ccc5dd7b1be6fe2b1f32ca6abde1da73fae79
Add a few livepatch modules and simple target modules that the included regression suite can run tests against:
- basic livepatching (multiple patches, atomic replace) - pre/post (un)patch callbacks - shadow variable API
Signed-off-by: Joe Lawrence joe.lawrence@redhat.com --- Documentation/livepatch/callbacks.txt | 489 +------------- MAINTAINERS | 1 + lib/Kconfig.debug | 21 + 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 | 236 +++++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/livepatch/Makefile | 8 + tools/testing/selftests/livepatch/README | 43 ++ tools/testing/selftests/livepatch/config | 1 + .../testing/selftests/livepatch/functions.sh | 164 +++++ .../selftests/livepatch/test-callbacks.sh | 607 ++++++++++++++++++ .../selftests/livepatch/test-livepatch.sh | 173 +++++ .../selftests/livepatch/test-shadow-vars.sh | 60 ++ 20 files changed, 1771 insertions(+), 484 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/README 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..182e31d4abce 100644 --- a/Documentation/livepatch/callbacks.txt +++ b/Documentation/livepatch/callbacks.txt @@ -118,488 +118,9 @@ 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 +Other Examples +==============
- % 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 +Sample livepatch modules demonstrating the callback API can be found in +samples/livepatch/ directory. These samples were modified for use in +kselftests and can be found in the lib/livepatch directory. diff --git a/MAINTAINERS b/MAINTAINERS index 6e950b8b4a41..d030087b5487 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8178,6 +8178,7 @@ F: arch/x86/kernel/livepatch.c F: Documentation/livepatch/ F: Documentation/ABI/testing/sysfs-kernel-livepatch F: samples/livepatch/ +F: tools/testing/selftests/livepatch/ L: live-patching@vger.kernel.org T: git git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching.git
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 64155e310a9f..dc5200273563 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1932,6 +1932,27 @@ config TEST_DEBUG_VIRTUAL
If unsure, say N.
+config TEST_LIVEPATCH + tristate "Test livepatching" + default n + depends on LIVEPATCH + depends on m + help + Test kernel livepatching features for correctness. The tests will + load test modules that will be livepatched in various scenarios. + + To run all the livepatching tests: + + make -C tools/testing/selftests TARGETS=livepatch run_tests + + Alternatively, individual tests may be invoked: + + tools/testing/selftests/livepatch/test-callbacks.sh + tools/testing/selftests/livepatch/test-livepatch.sh + tools/testing/selftests/livepatch/test-shadow-vars.sh + + 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..02f892f941dc --- /dev/null +++ b/lib/livepatch/test_klp_shadow_vars.c @@ -0,0 +1,236 @@ +// 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; +}; + +static 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); + } +} + +static 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_ATOMIC); + 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. + */ +static 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; +} + +static 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; +} + +static 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; +} + +static 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)); +} + +static 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(NULL); + 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_exit(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/README b/tools/testing/selftests/livepatch/README new file mode 100644 index 000000000000..b73cd0e2dd51 --- /dev/null +++ b/tools/testing/selftests/livepatch/README @@ -0,0 +1,43 @@ +==================== +Livepatch Self Tests +==================== + +This is a small set of sanity tests for the kernel livepatching. + +The test suite loads and unloads several test kernel modules to verify +livepatch behavior. Debug information is logged to the kernel's message +buffer and parsed for expected messages. (Note: the tests will clear +the message buffer between individual tests.) + + +Config +------ + +Set these config options and their prerequisites: + +CONFIG_LIVEPATCH=y +CONFIG_TEST_LIVEPATCH=m + + +Running the tests +----------------- + +Test kernel modules are built as part of lib/ (make modules) and need to +be installed (make modules_install) as the test scripts will modprobe +them. + +To run the livepatch selftests, from the top of the kernel source tree: + + % make -C tools/testing/selftests TARGETS=livepatch run_tests + + +Adding tests +------------ + +See the common functions.sh file for the existing collection of utility +functions, most importantly set_dynamic_debug() and check_result(). The +latter function greps the kernel's ring buffer for "livepatch:" and +"test_klp" strings, so tests be sure to include one of those strings for +result comparison. Other utility functions include general module +loading and livepatch loading helpers (waiting for patch transitions, +sysfs entries, etc.) 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..5fc6ec116ce5 --- /dev/null +++ b/tools/testing/selftests/livepatch/functions.sh @@ -0,0 +1,164 @@ +#!/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 + +# log(msg) - write message to kernel log +# msg - insightful words +function log() { + echo "$1" > /dev/kmsg +} + +# die(msg) - game over, man +# msg - dying words +function die() { + log "ERROR: $1" + 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 +} + +# loop_until(cmd) - loop a command until it is successful or $MAX_RETRIES, +# sleep $RETRY_INTERVAL between attempts +# cmd - command and its arguments to run +function loop_until() { + local cmd="$*" + local i=0 + while true; do + eval "$cmd" && return 0 + [[ $((i++)) -eq $MAX_RETRIES ]] && return 1 + sleep $RETRY_INTERVAL + done +} + +# wait_for_transition() - wait until no active livepatch transitions +function wait_for_transition() { + loop_until '! grep -q '^1$' /sys/kernel/livepatch/*/transition' || + die "failed to complete transition" +} + +# 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 $args" + log "${msg%% }" + ret=$(modprobe "$mod" "$args" 2>&1) + if [[ "$ret" != "" ]]; then + die "$ret" + fi + + # Wait for module in sysfs ... + loop_until '[[ -e "/sys/module/$mod" ]]' || + die "failed to load module $mod" + + # Wait for livepatch ... + if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then + + # Wait for livepatch in sysfs ... + loop_until '[[ -e "/sys/kernel/livepatch/$mod" ]]' || + die "failed to load module $mod (sysfs)" + 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 $args" + log "${msg%% }" + ret=$(modprobe "$mod" "$args" 2>&1) + if [[ "$ret" == "" ]]; then + die "$mod unexpectedly loaded" + fi + log "$ret" +} + +# 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 ... + loop_until '[[ $(cat "/sys/module/$mod/refcnt") == "0" ]]' || + die "failed to unload module $mod (refcnt)" + + log "% rmmod $mod" + ret=$(rmmod "$mod" 2>&1) + if [[ "$ret" != "" ]]; then + die "$ret" + fi + + # Wait for module in sysfs ... + loop_until '[[ ! -e "/sys/module/$mod" ]]' || + die "failed to unload module $mod (/sys/module)" + + # Wait for livepatch sysfs if applicable ... + if [[ $(modinfo "$mod" | awk '/^livepatch:/{print $NF}') == "Y" ]]; then + + loop_until '[[ ! -e "/sys/kernel/livepatch/$mod" ]]' || + die "failed to unload module $mod (/sys/livepatch)" + fi +} + +# disable_lp(modname) - disable a livepatch +# modname - module name to unload +function disable_lp() { + local mod="$1" + + log "% echo 0 > /sys/kernel/livepatch/$mod/enabled" + echo 0 > /sys/kernel/livepatch/"$mod"/enabled + + # Wait for livepatch enable to clear ... + loop_until '[[ $(cat "/sys/kernel/livepatch/$mod/enabled") == "0" ]]' || + die "failed to disable livepatch $mod" +} + +# 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" + + log "% echo $ret > /sys/module/$mod/parameters/pre_patch_ret" + echo "$ret" > /sys/module/"$mod"/parameters/pre_patch_ret + + # Wait for sysfs value to hold ... + loop_until '[[ $(cat "/sys/module/$mod/parameters/pre_patch_ret") == "$ret" ]]' || + die "failed to set pre_patch_ret parameter for $mod module" +} + +# check_result() - verify dmesg output +# TODO - better filter, out of order msgs, etc? +function check_result { + local expect="$*" + local result + + 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..a5a452f20b85 --- /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 + +. $(dirname $0)/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 +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 +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 +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition +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 +load_mod $MOD_TARGET +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition +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 +disable_lp $MOD_LIVEPATCH +wait_for_transition +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 +set_pre_patch_ret $MOD_LIVEPATCH -19 +load_failing_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition +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 +load_mod $MOD_TARGET +unload_mod $MOD_TARGET +disable_lp $MOD_LIVEPATCH +wait_for_transition +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 +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 +load_mod $MOD_LIVEPATCH2 +wait_for_transition +disable_lp $MOD_LIVEPATCH2 +wait_for_transition +disable_lp $MOD_LIVEPATCH +wait_for_transition +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 +load_mod $MOD_LIVEPATCH2 replace=1 +wait_for_transition +disable_lp $MOD_LIVEPATCH2 +wait_for_transition +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..5068c7d1a020 --- /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 + +. $(dirname $0)/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 $MOD_LIVEPATCH +wait_for_transition + +if [[ "$(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 + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +load_mod $MOD_REPLACE replace=0 +wait_for_transition + +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 + +grep 'live patched' /proc/cmdline > /dev/kmsg +grep 'live patched' /proc/meminfo > /dev/kmsg + +load_mod $MOD_REPLACE replace=1 +wait_for_transition + +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..04a37831e204 --- /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 + +. $(dirname $0)/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 04/25/2018 02:28 PM, Joe Lawrence wrote:
[ ... snip ... ]
base-commit: 0adb32858b0bddf4ada5f364a84ed60b196dbcda prerequisite-patch-id: 5ed747c1a89a5dc4bba08186e21f927d7f3bf049 prerequisite-patch-id: e9800288b71a9f339ea066e58d9ef70dece67083 prerequisite-patch-id: 415f2e190b1b50142c78f2940c7b8dd39b5321a0 prerequisite-patch-id: d229d9cf08af087e0a758d9df1da467103c2c200 prerequisite-patch-id: b8c7ef99b13c6b321cba5e8919ed0b3e29f213e9 prerequisite-patch-id: 4e10c0d08f151b18310fe0b1e5013d62db94cfeb prerequisite-patch-id: 33046b190c114d202f3a52e0e274dbb2b1907a4c prerequisite-patch-id: 6978944a725756317dd4e005d479b6101784aaf0 prerequisite-patch-id: cce9d3c7e1ae8887f387ca9e072552dc63479749 prerequisite-patch-id: c44ccc5dd7b1be6fe2b1f32ca6abde1da73fae79
Hi kbuild test robot folks,
I attempted to use the --base option with git format-patch as suggested by Philip, but the bot still sent me mail (addressed only to myself and cc'd kbuild-all@01.org) about build test ERRORs against the wrong base:
[auto build test ERROR on v4.16] [also build test ERROR on next-20180424] [cannot apply to linus/master jikos-livepatching/for-next]
I'm assuming operator error :( Here's a summary of my workflow:
* Save an .mbox of the entire base patchset, as posted to the live-patching list:
https://lkml.org/lkml/2018/3/23/665
* Create a "base" branch and apply the mbox:
% git checkout -b test_base v4.16 Switched to a new branch 'test_base'
% git am /tmp/pm.mbox Applying: livepatch: Use lists to manage patches, objects and functions Applying: livepatch: Free only structures with initialized kobject Applying: livepatch: Add atomic replace Applying: livepatch: Add an extra flag to distinguish registered patches Applying: livepatch: Remove replaced patches from the stack Applying: livepatch: Remove Nop structures when unused Applying: livepatch: Allow to replace even disabled patches Applying: livepatch: Atomic replace and cumulative patches documentation
* Create a new dev branch from the base, make a trivial change and commit:
% git checkout -b test_branch test_base % sed -i 's/^EXTRAVERSION =/EXTRAVERSION = .test/' Makefile % git commit Makefile -m 'test commit'
* Create .patch files with --base:
% git format-patch --base=v4.16 -1 --cover-letter % grep -e '^base-commit' -e 'prereq' 0000-cover-letter.patch base-commit: 0adb32858b0bddf4ada5f364a84ed60b196dbcda prerequisite-patch-id: 5ed747c1a89a5dc4bba08186e21f927d7f3bf049 prerequisite-patch-id: e9800288b71a9f339ea066e58d9ef70dece67083 prerequisite-patch-id: 415f2e190b1b50142c78f2940c7b8dd39b5321a0 prerequisite-patch-id: d229d9cf08af087e0a758d9df1da467103c2c200 prerequisite-patch-id: b8c7ef99b13c6b321cba5e8919ed0b3e29f213e9 prerequisite-patch-id: 4e10c0d08f151b18310fe0b1e5013d62db94cfeb prerequisite-patch-id: 33046b190c114d202f3a52e0e274dbb2b1907a4c prerequisite-patch-id: 6978944a725756317dd4e005d479b6101784aaf0
I notice that these patch-ids are only added to the cover-letter... do I need to force them each individual patch as well? /confused
Thanks,
-- 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
Hi, Joe
Sorry for the late response.
On 04/26, Joe Lawrence wrote:
On 04/25/2018 02:28 PM, Joe Lawrence wrote:
[ ... snip ... ]
base-commit: 0adb32858b0bddf4ada5f364a84ed60b196dbcda prerequisite-patch-id: 5ed747c1a89a5dc4bba08186e21f927d7f3bf049 prerequisite-patch-id: e9800288b71a9f339ea066e58d9ef70dece67083 prerequisite-patch-id: 415f2e190b1b50142c78f2940c7b8dd39b5321a0 prerequisite-patch-id: d229d9cf08af087e0a758d9df1da467103c2c200 prerequisite-patch-id: b8c7ef99b13c6b321cba5e8919ed0b3e29f213e9 prerequisite-patch-id: 4e10c0d08f151b18310fe0b1e5013d62db94cfeb prerequisite-patch-id: 33046b190c114d202f3a52e0e274dbb2b1907a4c prerequisite-patch-id: 6978944a725756317dd4e005d479b6101784aaf0 prerequisite-patch-id: cce9d3c7e1ae8887f387ca9e072552dc63479749 prerequisite-patch-id: c44ccc5dd7b1be6fe2b1f32ca6abde1da73fae79
Hi kbuild test robot folks,
I attempted to use the --base option with git format-patch as suggested by Philip, but the bot still sent me mail (addressed only to myself and cc'd kbuild-all@01.org) about build test ERRORs against the wrong base:
[auto build test ERROR on v4.16] [also build test ERROR on next-20180424] [cannot apply to linus/master jikos-livepatching/for-next]
I noticed this error report was for [PATCH v3] selftests/livepatch: introduce tests which doesn't include the base commit info.
I'm assuming operator error :( Here's a summary of my workflow:
- Save an .mbox of the entire base patchset, as posted to the
live-patching list:
https://lkml.org/lkml/2018/3/23/665
- Create a "base" branch and apply the mbox:
% git checkout -b test_base v4.16 Switched to a new branch 'test_base'
% git am /tmp/pm.mbox Applying: livepatch: Use lists to manage patches, objects and functions Applying: livepatch: Free only structures with initialized kobject Applying: livepatch: Add atomic replace Applying: livepatch: Add an extra flag to distinguish registered patches Applying: livepatch: Remove replaced patches from the stack Applying: livepatch: Remove Nop structures when unused Applying: livepatch: Allow to replace even disabled patches Applying: livepatch: Atomic replace and cumulative patches documentation
- Create a new dev branch from the base, make a trivial change and commit:
% git checkout -b test_branch test_base % sed -i 's/^EXTRAVERSION =/EXTRAVERSION = .test/' Makefile % git commit Makefile -m 'test commit'
- Create .patch files with --base:
% git format-patch --base=v4.16 -1 --cover-letter % grep -e '^base-commit' -e 'prereq' 0000-cover-letter.patch base-commit: 0adb32858b0bddf4ada5f364a84ed60b196dbcda prerequisite-patch-id: 5ed747c1a89a5dc4bba08186e21f927d7f3bf049 prerequisite-patch-id: e9800288b71a9f339ea066e58d9ef70dece67083 prerequisite-patch-id: 415f2e190b1b50142c78f2940c7b8dd39b5321a0 prerequisite-patch-id: d229d9cf08af087e0a758d9df1da467103c2c200 prerequisite-patch-id: b8c7ef99b13c6b321cba5e8919ed0b3e29f213e9 prerequisite-patch-id: 4e10c0d08f151b18310fe0b1e5013d62db94cfeb prerequisite-patch-id: 33046b190c114d202f3a52e0e274dbb2b1907a4c prerequisite-patch-id: 6978944a725756317dd4e005d479b6101784aaf0
I notice that these patch-ids are only added to the cover-letter... do I need to force them each individual patch as well? /confused
I think the work flow you described above is ok, you can just send them with git send-email after doing that, and base commit/prerequisite patch info in cover-letter is fine, the question here is I can't find the patch emails of your patchset except the cover letter in 0day's mail archive, do you send them as a whole series, could you tell the subjects of them so I can take a look in 0day's log.
Thanks, Xiaolong
Thanks,
-- 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 Fri, May 11, 2018 at 10:53:24AM +0800, Ye Xiaolong wrote:
Hi, Joe
Sorry for the late response.
Hi Xiaolong, no worries...
On 04/26, Joe Lawrence wrote:
On 04/25/2018 02:28 PM, Joe Lawrence wrote:
[ ... snip ... ]
base-commit: 0adb32858b0bddf4ada5f364a84ed60b196dbcda prerequisite-patch-id: 5ed747c1a89a5dc4bba08186e21f927d7f3bf049 prerequisite-patch-id: e9800288b71a9f339ea066e58d9ef70dece67083 prerequisite-patch-id: 415f2e190b1b50142c78f2940c7b8dd39b5321a0 prerequisite-patch-id: d229d9cf08af087e0a758d9df1da467103c2c200 prerequisite-patch-id: b8c7ef99b13c6b321cba5e8919ed0b3e29f213e9 prerequisite-patch-id: 4e10c0d08f151b18310fe0b1e5013d62db94cfeb prerequisite-patch-id: 33046b190c114d202f3a52e0e274dbb2b1907a4c prerequisite-patch-id: 6978944a725756317dd4e005d479b6101784aaf0 prerequisite-patch-id: cce9d3c7e1ae8887f387ca9e072552dc63479749 prerequisite-patch-id: c44ccc5dd7b1be6fe2b1f32ca6abde1da73fae79
Hi kbuild test robot folks,
I attempted to use the --base option with git format-patch as suggested by Philip, but the bot still sent me mail (addressed only to myself and cc'd kbuild-all@01.org) about build test ERRORs against the wrong base:
[auto build test ERROR on v4.16] [also build test ERROR on next-20180424] [cannot apply to linus/master jikos-livepatching/for-next]
I noticed this error report was for [PATCH v3] selftests/livepatch: introduce tests which doesn't include the base commit info.
That must have been it! Looking back in my mail archives, I don't see any complaints against v4. The bot must have sent me v3 mail just after I fired off v4.
[ ... snip workflow detail ... ]
I think the work flow you described above is ok, you can just send them with git send-email after doing that, and base commit/prerequisite patch info in cover-letter is fine, the question here is I can't find the patch emails of your patchset except the cover letter in 0day's mail archive, do you send them as a whole series, could you tell the subjects of them so I can take a look in 0day's log.
My patchset v4 (this subject/thread):
[PATCH v4 0/1] Add livepatch kselftests https://lkml.org/lkml/2018/4/25/1139
based on Petr's patchsets:
[PATCH 0/8] livepatch: Atomic replace feature https://lkml.org/lkml/2018/3/23/665
[PATCH v3 0/2] livepatch: Allocate and free shadow variables more safely https://lkml.org/lkml/2018/4/16/326
All of which should have been posted to linux-kernel as well as linux-livepatching. I can dig up Message-Ids or other headers if that helps any.
Regards,
-- 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 Wed, 25 Apr 2018, Joe Lawrence wrote:
This round incorporates feedback from SUSE folks, Miroslav, Petr and Libor. Thanks for the reviews and feedback!
Like the previous version, this applies on top of Petr's shadow variable changes and the atomic replace patchset.
I skimmed through it and I did not find anything suspicious. It also works as advertised. It'd great if someone from kselftest ML took a look.
Thanks, Miroslav -- 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
linux-kselftest-mirror@lists.linaro.org
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Joe Lawrence -
Miroslav Benes -
Ye Xiaolong