From b248ede2ef2792d364bd305e5e92e24921c924a8 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Fri, 17 Feb 2012 16:26:38 +0100 Subject: slirp: Fix requeuing of batchq packets in if_start In case we requeued a packet that was the head of a longer session queue, we failed to restore this ordering. Also, we did not properly deal with changes to Slirp::next_m. Instead of a cumbersome roll back, this fix simply avoids any changes until we know if the packet was actually sent. Both fixes crashes due to inconsistent queues and simplifies the logic. Thanks to Zhi Yong Wu who found the reason for these crashes. CC: Zhi Yong Wu CC: Fabien Chouteau Signed-off-by: Jan Kiszka --- slirp/if.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) (limited to 'slirp') diff --git a/slirp/if.c b/slirp/if.c index 8e0cac2a5b..710ec230e6 100644 --- a/slirp/if.c +++ b/slirp/if.c @@ -154,6 +154,7 @@ if_start(Slirp *slirp) { uint64_t now = qemu_get_clock_ns(rt_clock); int requeued = 0; + bool from_batchq = false; struct mbuf *ifm, *ifqt; DEBUG_CALL("if_start"); @@ -179,13 +180,26 @@ if_start(Slirp *slirp) else ifm = slirp->if_batchq.ifq_next; - /* Set which packet to send on next iteration */ - slirp->next_m = ifm->ifq_next; + from_batchq = true; } + + slirp->if_queued--; + + /* Try to send packet unless it already expired */ + if (ifm->expiration_date >= now && !if_encap(slirp, ifm)) { + /* Packet is delayed due to pending ARP resolution */ + requeued++; + goto out; + } + + if (from_batchq) { + /* Set which packet to send on next iteration */ + slirp->next_m = ifm->ifq_next; + } + /* Remove it from the queue */ ifqt = ifm->ifq_prev; remque(ifm); - slirp->if_queued--; /* If there are more packets for this session, re-queue them */ if (ifm->ifs_next != /* ifm->ifs_prev != */ ifm) { @@ -200,20 +214,9 @@ if_start(Slirp *slirp) ifm->ifq_so->so_nqueued = 0; } - if (ifm->expiration_date < now) { - /* Expired */ - m_free(ifm); - } else { - /* Encapsulate the packet for sending */ - if (if_encap(slirp, ifm)) { - m_free(ifm); - } else { - /* re-queue */ - insque(ifm, ifqt); - requeued++; - } - } + m_free(ifm); + out: if (slirp->if_queued) goto again; -- cgit v1.2.3