4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Marcelo Ricardo Leitner <[email protected]> [ Upstream commit 2dcab598484185dea7ec22219c76dcdd59e3cb90 ] Alexander Popov reported that an application may trigger a BUG_ON in sctp_wait_for_sndbuf if the socket tx buffer is full, a thread is waiting on it to queue more data and meanwhile another thread peels off the association being used by the first thread. This patch replaces the BUG_ON call with a proper error handling. It will return -EPIPE to the original sendmsg call, similarly to what would have been done if the association wasn't found in the first place. Acked-by: Alexander Popov <[email protected]> Signed-off-by: Marcelo Ricardo Leitner <[email protected]> Reviewed-by: Xin Long <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- net/sctp/socket.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -7427,7 +7427,8 @@ static int sctp_wait_for_sndbuf(struct s */ release_sock(sk); current_timeo = schedule_timeout(current_timeo); - BUG_ON(sk != asoc->base.sk); + if (sk != asoc->base.sk) + goto do_error; lock_sock(sk); *timeo_p = current_timeo;
