[PATCH v4 1/1] selftests/livepatch: introduce tests

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