diff options
| author | David Gwynne <dlg@cvs.openbsd.org> | 2019-08-16 04:09:03 +0000 |
|---|---|---|
| committer | David Gwynne <dlg@cvs.openbsd.org> | 2019-08-16 04:09:03 +0000 |
| commit | 7578bdf179c7036fa48c0d5b572924810eb8eaac (patch) | |
| tree | b587c141a49ab422b249c793c687c8e449fb84b3 | |
| parent | f4d81b40d01e780385e79f509dc699e74e43586b (diff) | |
ifq_hdatalen should keep the mbuf it's looking at, not leak it.
ie, use ifq_deq_rollback after looking at the head mbuf instead of
ifq_deq_commit.
this is used in tun/tap, where it had the effect that you'd get the
datalen for the packet, and then when you try to read that many
bytes it had gone. cool and normal.
this was found by a student who was trying to do just that. i've
always just read the packet into a large buffer.
| -rw-r--r-- | sys/net/ifq.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/net/ifq.c b/sys/net/ifq.c index 302277c2e7b..20ad6c14b5e 100644 --- a/sys/net/ifq.c +++ b/sys/net/ifq.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ifq.c,v 1.33 2019/07/03 10:19:45 dlg Exp $ */ +/* $OpenBSD: ifq.c,v 1.34 2019/08/16 04:09:02 dlg Exp $ */ /* * Copyright (c) 2015 David Gwynne <dlg@openbsd.org> @@ -397,7 +397,7 @@ ifq_hdatalen(struct ifqueue *ifq) m = ifq_deq_begin(ifq); if (m != NULL) { len = m->m_pkthdr.len; - ifq_deq_commit(ifq, m); + ifq_deq_rollback(ifq, m); } return (len); |