diff options
Diffstat (limited to 'kernel/livepatch/core.c')
| -rw-r--r-- | kernel/livepatch/core.c | 58 |
1 files changed, 47 insertions, 11 deletions
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index ecbc9b6aba3a..0e73fac55f8e 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -59,7 +59,7 @@ static void klp_find_object_module(struct klp_object *obj) if (!klp_is_module(obj)) return; - rcu_read_lock_sched(); + guard(rcu)(); /* * We do not want to block removal of patched modules and therefore * we do not take a reference here. The patches are removed by @@ -75,8 +75,6 @@ static void klp_find_object_module(struct klp_object *obj) */ if (mod && mod->klp_alive) obj->mod = mod; - - rcu_read_unlock_sched(); } static bool klp_initialized(void) @@ -346,6 +344,8 @@ 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>/stack_order * /sys/kernel/livepatch/<patch>/<object> * /sys/kernel/livepatch/<patch>/<object>/patched * /sys/kernel/livepatch/<patch>/<object>/<function,sympos> @@ -401,7 +401,7 @@ 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 +410,7 @@ 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 +442,47 @@ 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 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); @@ -566,9 +599,12 @@ static int klp_add_object_nops(struct klp_patch *patch, } /* - * Add 'nop' functions which simply return to the caller to run - * the original function. The 'nop' functions are added to a - * patch to facilitate a 'replace' mode. + * Add 'nop' functions which simply return to the caller to run the + * original function. + * + * They are added only when the atomic replace mode is used and only for + * functions which are currently livepatched but are no longer included + * in the new livepatch. */ static int klp_add_nops(struct klp_patch *patch) { @@ -973,7 +1009,7 @@ static int __klp_disable_patch(struct klp_patch *patch) if (klp_transition_patch) return -EBUSY; - klp_init_transition(patch, KLP_UNPATCHED); + klp_init_transition(patch, KLP_TRANSITION_UNPATCHED); klp_for_each_object(patch, obj) if (obj->patched) @@ -1008,7 +1044,7 @@ static int __klp_enable_patch(struct klp_patch *patch) pr_notice("enabling patch '%s'\n", patch->mod->name); - klp_init_transition(patch, KLP_PATCHED); + klp_init_transition(patch, KLP_TRANSITION_PATCHED); /* * Enforce the order of the func->transition writes in |