The following directory structure will allow for cases when the same function name exists in a single object. /sys/kernel/livepatch/<patch>/<object>/<function.number> The number corresponds to the nth occurrence of the symbol name in kallsyms for the patched object. An example of this issue is documented here: https://github.com/dynup/kpatch/issues/493 Signed-off-by: Chris J Arges <chris.j.arges@xxxxxxxxxxxxx> --- Documentation/ABI/testing/sysfs-kernel-livepatch | 2 +- kernel/livepatch/core.c | 45 ++++++++++++++++++++++-- 2 files changed, 44 insertions(+), 3 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-kernel-livepatch b/Documentation/ABI/testing/sysfs-kernel-livepatch index 5bf42a8..dcd36db 100644 --- a/Documentation/ABI/testing/sysfs-kernel-livepatch +++ b/Documentation/ABI/testing/sysfs-kernel-livepatch @@ -33,7 +33,7 @@ Description: The object directory contains subdirectories for each function that is patched within the object. -What: /sys/kernel/livepatch/<patch>/<object>/<function> +What: /sys/kernel/livepatch/<patch>/<object>/<function.number> Date: Nov 2014 KernelVersion: 3.19.0 Contact: live-patching@xxxxxxxxxxxxxxx diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 6e53441..6bcf600 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -587,7 +587,7 @@ EXPORT_SYMBOL_GPL(klp_enable_patch); * /sys/kernel/livepatch/<patch> * /sys/kernel/livepatch/<patch>/enabled * /sys/kernel/livepatch/<patch>/<object> - * /sys/kernel/livepatch/<patch>/<object>/<func> + * /sys/kernel/livepatch/<patch>/<object>/<func.number> */ static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -727,13 +727,54 @@ static void klp_free_patch(struct klp_patch *patch) kobject_put(&patch->kobj); } +static int klp_get_func_pos_callback(void *data, const char *name, + struct module *mod, unsigned long addr) +{ + struct klp_find_arg *args = data; + + if ((mod && !args->objname) || (!mod && args->objname)) + return 0; + + if (strcmp(args->name, name)) + return 0; + + if (args->objname && strcmp(args->objname, mod->name)) + return 0; + + /* on address match, return 1 to break kallsyms_on_each_symbol loop */ + if (args->addr == addr) + return 1; + + /* if we don't match addr, count instance of named symbol */ + args->count++; + + return 0; +} + +static int klp_get_func_pos(struct klp_object *obj, struct klp_func *func) +{ + struct klp_find_arg args = { + .objname = obj->name, + .name = func->old_name, + .addr = func->old_addr, + .count = 0, + }; + + mutex_lock(&module_mutex); + kallsyms_on_each_symbol(klp_get_func_pos_callback, &args); + mutex_unlock(&module_mutex); + + return args.count; +} + static int klp_init_func(struct klp_object *obj, struct klp_func *func) { INIT_LIST_HEAD(&func->stack_node); func->state = KLP_DISABLED; return kobject_init_and_add(&func->kobj, &klp_ktype_func, - &obj->kobj, "%s", func->old_name); + &obj->kobj, "%s,%d", func->old_name, + klp_get_func_pos(obj, func)); } /* parts of the initialization that is done only when the object is loaded */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
