From bc6f2a757d525e001268c3658bd88822e768f8db Mon Sep 17 00:00:00 2001 From: YueHaibing Date: Tue, 11 Jun 2019 23:00:07 +0800 Subject: kernel/module: Fix mem leak in module_add_modinfo_attrs 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") Reviewed-by: Miroslav Benes Signed-off-by: YueHaibing Signed-off-by: Jessica Yu --- kernel/module.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 1a0d8cab9eb7..c1517053e9d6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1708,6 +1708,8 @@ 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; @@ -1722,24 +1724,34 @@ 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: + if (i > 0) + 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; @@ -1827,7 +1839,7 @@ 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: @@ -1863,7 +1875,7 @@ 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) { } @@ -1879,7 +1891,7 @@ 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); -- cgit v1.2.3-55-g7522