On Sun, 2020-05-24 at 23:50 +0900, Tetsuo Handa wrote: > syzbot found a NULL pointer dereference bug inside mptcp_recvmsg() due to > ssock == NULL, but this bug manifested inside selinux_socket_recvmsg() > because pr_debug() was no-op [1]. > > pr_debug("fallback-read subflow=%p", > mptcp_subflow_ctx(ssock->sk)); > copied = sock_recvmsg(ssock, msg, flags);
> Since console loglevel used by syzkaller will not print KERN_DEBUG > messages to consoles, always evaluating pr_devel()/pr_debug() messages > will not cause too much console output. Thus, let's allow fuzzers to > always evaluate pr_devel()/pr_debug() messages. While I think this is rather unnecessary, what about dev_dbg/netdev_dbg/netif_dbg et al ?