On Fri, Dec 10, 2021 at 11:38:32AM +0800, Jiapeng Chong wrote:
> Fix following coccicheck warning:
>
> ./drivers/staging/r8188eu/os_dep/ioctl_linux.c:4253:8-15: WARNING
> opportunity for memdup_user.
>
> Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
> ---
> drivers/staging/r8188eu/os_dep/ioctl_linux.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/staging/r8188eu/os_dep/ioctl_linux.c b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
> index 56adfe4087a8..c6a2fbfe8f26 100644
> --- a/drivers/staging/r8188eu/os_dep/ioctl_linux.c
> +++ b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
> @@ -4250,17 +4250,12 @@ static int rtw_test(
> DBG_88E("+%s\n", __func__);
> len = wrqu->data.length;
>
> - pbuf = kzalloc(len, GFP_KERNEL);
> - if (!pbuf) {
> - DBG_88E("%s: no memory!\n", __func__);
> - return -ENOMEM;
> - }
> -
> - if (copy_from_user(pbuf, wrqu->data.pointer, len)) {
> - kfree(pbuf);
> + pbuf = memdup_user(wrqu->data.pointer, len);
This code assumes that the user is going to give us a NUL terminated
string which is not necessarily true. The original code was buggy too.
Anyway, please fix it. Use strndup_user() and mention that it is a bug
fix in the commit message:
pbuf = strndup_user(wrqu->data.pointer, len);
Add a Fixes tag.
regards,
dan carpenter
