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Merge branch 'for-6.11/sysfs-patch-replace' into for-linus

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This commit is contained in:
Petr Mladek 2024-07-23 17:13:10 +02:00
commit ea5377ec49
3 changed files with 70 additions and 3 deletions
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8
Documentation/ABI/testing/sysfs-kernel-livepatch
View file

@ -47,6 +47,14 @@ Description:
disabled when the feature is used. See
Documentation/livepatch/livepatch.rst for more information.
What: /sys/kernel/livepatch/<patch>/replace
Date: Jun 2024
KernelVersion: 6.11.0
Contact: live-patching@vger.kernel.org
Description:
An attribute which indicates whether the patch supports
atomic-replace.
What: /sys/kernel/livepatch/<patch>/<object>
Date: Nov 2014
KernelVersion: 3.19.0

17
kernel/livepatch/core.c
View file

@ -346,6 +346,7 @@ int klp_apply_section_relocs(struct module *pmod, Elf_Shdr *sechdrs,
* /sys/kernel/livepatch/<patch>/enabled
* /sys/kernel/livepatch/<patch>/transition
* /sys/kernel/livepatch/<patch>/force
* /sys/kernel/livepatch/<patch>/replace
* /sys/kernel/livepatch/<patch>/<object>
* /sys/kernel/livepatch/<patch>/<object>/patched
* /sys/kernel/livepatch/<patch>/<object>/<function,sympos>
@ -401,7 +402,7 @@ static ssize_t enabled_show(struct kobject *kobj,
struct klp_patch *patch;
patch = container_of(kobj, struct klp_patch, kobj);
return snprintf(buf, PAGE_SIZE-1, "%d\n", patch->enabled);
return sysfs_emit(buf, "%d\n", patch->enabled);
}
static ssize_t transition_show(struct kobject *kobj,
@ -410,8 +411,7 @@ static ssize_t transition_show(struct kobject *kobj,
struct klp_patch *patch;
patch = container_of(kobj, struct klp_patch, kobj);
return snprintf(buf, PAGE_SIZE-1, "%d\n",
patch == klp_transition_patch);
return sysfs_emit(buf, "%d\n", patch == klp_transition_patch);
}
static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr,
@ -443,13 +443,24 @@ static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr,
return count;
}
static ssize_t replace_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct klp_patch *patch;
patch = container_of(kobj, struct klp_patch, kobj);
return sysfs_emit(buf, "%d\n", patch->replace);
}
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 attribute *klp_patch_attrs[] = {
&enabled_kobj_attr.attr,
&transition_kobj_attr.attr,
&force_kobj_attr.attr,
&replace_kobj_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(klp_patch);

48
tools/testing/selftests/livepatch/test-sysfs.sh
View file

@ -18,6 +18,7 @@ check_sysfs_rights "$MOD_LIVEPATCH" "" "drwxr-xr-x"
check_sysfs_rights "$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" "transition" "-r--r--r--"
check_sysfs_value "$MOD_LIVEPATCH" "transition" "0"
check_sysfs_rights "$MOD_LIVEPATCH" "vmlinux/patched" "-r--r--r--"
@ -83,4 +84,51 @@ test_klp_callbacks_demo: post_unpatch_callback: vmlinux
livepatch: 'test_klp_callbacks_demo': unpatching complete
% rmmod test_klp_callbacks_demo"
start_test "sysfs test replace enabled"
MOD_LIVEPATCH=test_klp_atomic_replace
load_lp $MOD_LIVEPATCH replace=1
check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
check_sysfs_value "$MOD_LIVEPATCH" "replace" "1"
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=1
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"
start_test "sysfs test replace disabled"
load_lp $MOD_LIVEPATCH replace=0
check_sysfs_rights "$MOD_LIVEPATCH" "replace" "-r--r--r--"
check_sysfs_value "$MOD_LIVEPATCH" "replace" "0"
disable_lp $MOD_LIVEPATCH
unload_lp $MOD_LIVEPATCH
check_result "% insmod test_modules/$MOD_LIVEPATCH.ko replace=0
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"
exit 0