Messages in this thread Patch in this message | | | From | YueHaibing <> | Subject | [PATCH v3] kernel/module: Fix mem leak in module_add_modinfo_attrs | Date | Mon, 3 Jun 2019 22:45:54 +0800 |
| |
In module_add_modinfo_attrs if sysfs_create_file fails, we forget to free allocated modinfo_attrs and roll back the sysfs files.
Fixes: 03e88ae1b13d ("[PATCH] fix module sysfs files reference counting") Signed-off-by: YueHaibing <yuehaibing@huawei.com> --- v3: reuse module_remove_modinfo_attrs v2: free from '--i' instead of 'i--' --- kernel/module.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c index 80c7c09..c6b8912 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1697,6 +1697,8 @@ static int add_usage_links(struct module *mod) return ret; } +static void module_remove_modinfo_attrs(struct module *mod, int end); + static int module_add_modinfo_attrs(struct module *mod) { struct module_attribute *attr; @@ -1711,24 +1713,33 @@ static int module_add_modinfo_attrs(struct module *mod) return -ENOMEM; temp_attr = mod->modinfo_attrs; - for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { + for (i = 0; (attr = modinfo_attrs[i]); i++) { if (!attr->test || attr->test(mod)) { memcpy(temp_attr, attr, sizeof(*temp_attr)); sysfs_attr_init(&temp_attr->attr); error = sysfs_create_file(&mod->mkobj.kobj, &temp_attr->attr); + if (error) + goto error_out; ++temp_attr; } } + + return 0; + +error_out: + module_remove_modinfo_attrs(mod, --i); return error; } -static void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod, int end) { struct module_attribute *attr; int i; for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { + if (end >= 0 && i > end) + break; /* pick a field to test for end of list */ if (!attr->attr.name) break; @@ -1816,7 +1827,7 @@ static int mod_sysfs_setup(struct module *mod, return 0; out_unreg_modinfo_attrs: - module_remove_modinfo_attrs(mod); + module_remove_modinfo_attrs(mod, -1); out_unreg_param: module_param_sysfs_remove(mod); out_unreg_holders: @@ -1852,7 +1863,7 @@ static void mod_sysfs_fini(struct module *mod) { } -static void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod, int end) { } @@ -1868,7 +1879,7 @@ static void init_param_lock(struct module *mod) static void mod_sysfs_teardown(struct module *mod) { del_usage_links(mod); - module_remove_modinfo_attrs(mod); + module_remove_modinfo_attrs(mod, -1); module_param_sysfs_remove(mod); kobject_put(mod->mkobj.drivers_dir); kobject_put(mod->holders_dir); -- 1.8.3.1
| |