tree c655f98ff56baaab4571e8eab59ab6d68fca67cd
parent 8048ced9beb21a52e3305f3332ae82020619f24e
author Alexander Potapenko <glider@google.com> 1493139106 +0200
committer David S. Miller <davem@davemloft.net> 1493143552 -0400

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: Alexander Potapenko <glider@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>