If there is a failure during copy_from_user or user-provided data
buffer is invalid, rtw_debugfs_copy_from_user should return negative
error code instead of a positive value count.
Fix this bug by returning correct error code. Moreover, the check
of buffer against null is removed since it will be handled by
copy_from_user.
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Reviewed-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/tencent_D2EB102CC7435C0110154E62ECA6A7D67505@qq.com
tmp_len = (count > size - 1 ? size - 1 : count);
- if (!buffer || copy_from_user(tmp, buffer, tmp_len))
- return count;
+ if (copy_from_user(tmp, buffer, tmp_len))
+ return -EFAULT;
tmp[tmp_len] = '\0';