net/packet: check length in getsockopt() called with PACKET_HDRLEN
In the case getsockopt() is called with PACKET_HDRLEN and optlen < 4 |val| remains uninitialized and the syscall may behave differently depending on its value, and even copy garbage to userspace on certain architectures. To fix this we now return -EINVAL if optlen is too small. This bug has been detected with KMSAN. Signed-off-by: NAlexander Potapenko <glider@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Showing
想要评论请 注册 或 登录