For very small autoclose timeouts (e.g. 0 or close to 0 due to overflows) it's possible that the timer is executed immediately after is set, before there is a chance to increase the association reference counter. To avoid this race, always reference the association before calling mod_timer() and dereference it back if the timer was already active. Signed-off-by: Andrei Pelinescu-Onciul <andrei@xxxxxxxxx> --- net/sctp/output.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/net/sctp/output.c b/net/sctp/output.c index b94c211..8c39bd2 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -586,8 +586,9 @@ int sctp_packet_transmit(struct sctp_packet *packet) timer = &asoc->timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE]; timeout = asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]; - if (!mod_timer(timer, jiffies + timeout)) - sctp_association_hold(asoc); + sctp_association_hold(asoc); + if (mod_timer(timer, jiffies + timeout)) + sctp_association_put(asoc); /* already active, deref */ } } -- 1.6.5.2 -- 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
