Commit a0fb05d1 authored Sep 07, 2013 by Daniel Borkmann Committed by David S. Miller Sep 11, 2013

net: sctp: fix bug in sctp_poll for SOCK_SELECT_ERR_QUEUE



If we do not add braces around ...

  mask |= POLLERR |
          sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0;

... then this condition always evaluates to true as POLLERR is
defined as 8 and binary or'd with whatever result comes out of
sock_flag(). Hence instead of (X | Y) ? A : B, transform it into
X | (Y ? A : B). Unfortunatelty, commit 8facd5fb ("net: fix
smatch warnings inside datagram_poll") forgot about SCTP. :-(

Introduced by 7d4c04fc ("net: add option to enable error queue
packets waking select").

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent ae7b4e1f

net/sctp/socket.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -6176,7 +6176,7 @@ unsigned int sctp_poll(struct file file, struct socket sock, poll_table *wait)
		/* Is there any exceptional events? */
		if (sk->sk_err \|\| !skb_queue_empty(&sk->sk_error_queue))
		mask \|= POLLERR \|
		sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0;
		(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
		if (sk->sk_shutdown & RCV_SHUTDOWN)
		mask \|= POLLRDHUP \| POLLIN \| POLLRDNORM;
		if (sk->sk_shutdown == SHUTDOWN_MASK)

Admin message