Re: [PATCH] kernel/module: Fix mem leak in module_add_modinfo_attrs

From: Yuehaibing
Date: Thu May 30 2019 - 05:28:05 EST


Friendly ping...

On 2019/5/16 0:12, YueHaibing wrote:
> 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@xxxxxxxxxx>
> ---
> kernel/module.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/module.c b/kernel/module.c
> index 0b9aa8a..7da73c4 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -1714,15 +1714,29 @@ 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:
> + for (; (attr = &mod->modinfo_attrs[i]) && i >= 0; i--) {
> + if (!attr->attr.name)
> + break;
> + sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
> + if (attr->free)
> + attr->free(mod);
> + }
> + kfree(mod->modinfo_attrs);
> return error;
> }
>
>