diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-livepatch | 9 | ||||
| -rw-r--r-- | kernel/livepatch/core.c | 24 | ||||
| -rwxr-xr-x | tools/testing/selftests/livepatch/test-sysfs.sh | 71 |
3 files changed, 104 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-livepatch b/Documentation/ABI/testing/sysfs-kernel-livepatch index 3735d868013d..3c3f36b32b57 100644 --- a/Documentation/ABI/testing/sysfs-kernel-livepatch +++ b/Documentation/ABI/testing/sysfs-kernel-livepatch @@ -55,6 +55,15 @@ Description: An attribute which indicates whether the patch supports atomic-replace. +What: /sys/kernel/livepatch/<patch>/stack_order +Date: Jan 2025 +KernelVersion: 6.14.0 +Description: + This attribute specifies the sequence in which live patch modules + are applied to the system. If multiple live patches modify the same + function, the implementation with the biggest 'stack_order' number + is used, unless a transition is currently in progress. + What: /sys/kernel/livepatch/<patch>/<object> Date: Nov 2014 KernelVersion: 3.19.0 diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 3c21c31796db..0cd39954d5a1 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -347,6 +347,7 @@ int klp_apply_section_relocs(struct module *pmod, Elf_Shdr *sechdrs, * /sys/kernel/livepatch/<patch>/transition * /sys/kernel/livepatch/<patch>/force * /sys/kernel/livepatch/<patch>/replace + * /sys/kernel/livepatch/<patch>/stack_order * /sys/kernel/livepatch/<patch>/<object> * /sys/kernel/livepatch/<patch>/<object>/patched * /sys/kernel/livepatch/<patch>/<object>/<function,sympos> @@ -452,15 +453,38 @@ static ssize_t replace_show(struct kobject *kobj, return sysfs_emit(buf, "%d\n", patch->replace); } +static ssize_t stack_order_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct klp_patch *patch, *this_patch; + int stack_order = 0; + + this_patch = container_of(kobj, struct klp_patch, kobj); + + mutex_lock(&klp_mutex); + + klp_for_each_patch(patch) { + stack_order++; + if (patch == this_patch) + break; + } + + mutex_unlock(&klp_mutex); + + return sysfs_emit(buf, "%d\n", stack_order); +} + static struct kobj_attribute enabled_kobj_attr = __ATTR_RW(enabled); static struct kobj_attribute transition_kobj_attr = __ATTR_RO(transition); static struct kobj_attribute force_kobj_attr = __ATTR_WO(force); static struct kobj_attribute replace_kobj_attr = __ATTR_RO(replace); +static struct kobj_attribute stack_order_kobj_attr = __ATTR_RO(stack_order); static struct attribute *klp_patch_attrs[] = { &enabled_kobj_attr.attr, &transition_kobj_attr.attr, &force_kobj_attr.attr, &replace_kobj_attr.attr, + &stack_order_kobj_attr.attr, NULL }; ATTRIBUTE_GROUPS(klp_patch); diff --git a/tools/testing/selftests/livepatch/test-sysfs.sh b/tools/testing/selftests/livepatch/test-sysfs.sh index 2c91428d2997..58fe1d96997c 100755 --- a/tools/testing/selftests/livepatch/test-sysfs.sh +++ b/tools/testing/selftests/livepatch/test-sysfs.sh @@ -5,6 +5,8 @@ . $(dirname $0)/functions.sh MOD_LIVEPATCH=test_klp_livepatch +MOD_LIVEPATCH2=test_klp_callbacks_demo +MOD_LIVEPATCH3=test_klp_syscall setup_config @@ -19,6 +21,8 @@ check_sysfs_rights "$MOD_LIVEPATCH" "enabled" "-rw-r--r--" check_sysfs_value "$MOD_LIVEPATCH" "enabled" "1" check_sysfs_rights "$MOD_LIVEPATCH" "force" "--w-------" check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--" +check_sysfs_rights "$MOD_LIVEPATCH" "stack_order" "-r--r--r--" +check_sysfs_value "$MOD_LIVEPATCH" "stack_order" "1" check_sysfs_rights "$MOD_LIVEPATCH" "transition" "-r--r--r--" check_sysfs_value "$MOD_LIVEPATCH" "transition" "0" check_sysfs_rights "$MOD_LIVEPATCH" "vmlinux/patched" "-r--r--r--" @@ -131,4 +135,71 @@ livepatch: '$MOD_LIVEPATCH': completing unpatching transition livepatch: '$MOD_LIVEPATCH': unpatching complete % rmmod $MOD_LIVEPATCH" +start_test "sysfs test stack_order value" + +load_lp $MOD_LIVEPATCH + +check_sysfs_value "$MOD_LIVEPATCH" "stack_order" "1" + +load_lp $MOD_LIVEPATCH2 + +check_sysfs_value "$MOD_LIVEPATCH2" "stack_order" "2" + +load_lp $MOD_LIVEPATCH3 + +check_sysfs_value "$MOD_LIVEPATCH3" "stack_order" "3" + +disable_lp $MOD_LIVEPATCH2 +unload_lp $MOD_LIVEPATCH2 + +check_sysfs_value "$MOD_LIVEPATCH" "stack_order" "1" +check_sysfs_value "$MOD_LIVEPATCH3" "stack_order" "2" + +disable_lp $MOD_LIVEPATCH3 +unload_lp $MOD_LIVEPATCH3 + +disable_lp $MOD_LIVEPATCH +unload_lp $MOD_LIVEPATCH + +check_result "% insmod test_modules/$MOD_LIVEPATCH.ko +livepatch: enabling patch '$MOD_LIVEPATCH' +livepatch: '$MOD_LIVEPATCH': initializing patching transition +livepatch: '$MOD_LIVEPATCH': starting patching transition +livepatch: '$MOD_LIVEPATCH': completing patching transition +livepatch: '$MOD_LIVEPATCH': patching complete +% insmod test_modules/$MOD_LIVEPATCH2.ko +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: '$MOD_LIVEPATCH2': patching complete +% insmod test_modules/$MOD_LIVEPATCH3.ko +livepatch: enabling patch '$MOD_LIVEPATCH3' +livepatch: '$MOD_LIVEPATCH3': initializing patching transition +livepatch: '$MOD_LIVEPATCH3': starting patching transition +livepatch: '$MOD_LIVEPATCH3': completing patching transition +livepatch: '$MOD_LIVEPATCH3': patching complete +% echo 0 > $SYSFS_KLP_DIR/$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 +% echo 0 > $SYSFS_KLP_DIR/$MOD_LIVEPATCH3/enabled +livepatch: '$MOD_LIVEPATCH3': initializing unpatching transition +livepatch: '$MOD_LIVEPATCH3': starting unpatching transition +livepatch: '$MOD_LIVEPATCH3': completing unpatching transition +livepatch: '$MOD_LIVEPATCH3': unpatching complete +% rmmod $MOD_LIVEPATCH3 +% echo 0 > $SYSFS_KLP_DIR/$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" + exit 0 |