On Tue, Feb 21, 2017 at 1:56 PM, Marcelo <marcelo.leitner@xxxxxxxxx> wrote: > > > Em 21 de fevereiro de 2017 13:08:44 BRT, Ben Hutchings <ben@xxxxxxxxxxxxxxx> escreveu: >>On Thu, 2017-02-16 at 09:53 -0800, Greg Kroah-Hartman wrote: >>> 4.4-stable review patch. If anyone has any objections, please let me >>know. >>> >>> ------------------ >>> >>> From: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> >>> >>> >>> [ Upstream commit 2dcab598484185dea7ec22219c76dcdd59e3cb90 ] >>[...] >>> --- a/net/sctp/socket.c >>> +++ b/net/sctp/socket.c >>> @@ -6960,7 +6960,8 @@ 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; >> >>This function normally returns with sk still locked, but in this case >>it returns with sk unlocked. Perhaps this check should be moved after >>the lock_sock(sk)? >> > > Looks like so. Will check more in a few. Thanks Ben Yes, we need to move the check to after the lock_sock(sk) call. There is also another problem: consider a thread A sending a packet to a new asoc (which creates a new asoc during sctp_sendsmg), and while waiting for more sndbuf space, it gets peeled off by another thread. This would cause a double-free of the asoc as sctp_sendmsg() will free this asoc thinking it errored out but it actually now belongs to another thread. Testing both patches now, should be ready by tomorrow. Marcelo > >>Ben. >> >>> lock_sock(sk); >>> >>> *timeo_p = current_timeo; >>> >>> > > -- > Enviado de meu dispositivo Android com K-9 mail. Desculpe-me pela brevidade. -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
