From: gfree.wind@foxmail.com
To: pablo@netfilter.org, netfilter-devel@vger.kernel.org
Cc: Gao Feng <fgao@ikuai8.com>
Subject: [PATCH nf 1/1] netfilter: cttimeout: Fix one possible use-after-free issue
Date: Thu, 6 Apr 2017 19:09:09 +0800 [thread overview]
Message-ID: <1491476949-92872-1-git-send-email-gfree.wind@foxmail.com> (raw)
From: Gao Feng <fgao@ikuai8.com>
The function ctnl_untimeout is used to untimeout every conntrack
which is using the timeout. But it is necessary to add one barrier
synchronize_rcu because of racing. Maybe one conntrack has already
owned this timeout, but it is not inserted into unconfirmed list or
the hash list, when ctnl_untimeout untimeout the conntracks
Signed-off-by: Gao Feng <fgao@ikuai8.com>
---
net/netfilter/nfnetlink_cttimeout.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/net/netfilter/nfnetlink_cttimeout.c b/net/netfilter/nfnetlink_cttimeout.c
index 47d6656..af0cc87 100644
--- a/net/netfilter/nfnetlink_cttimeout.c
+++ b/net/netfilter/nfnetlink_cttimeout.c
@@ -304,6 +304,11 @@ static void ctnl_untimeout(struct net *net, struct ctnl_timeout *timeout)
spinlock_t *lock;
int i, cpu;
+ /* Make sure the conntrack using the timeout already in the unconfirmed
+ * list or in the hash table.
+ */
+ synchronize_rcu();
+
for_each_possible_cpu(cpu) {
struct ct_pcpu *pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
--
1.9.1
next reply other threads:[~2017-04-06 11:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-06 11:09 gfree.wind [this message]
2017-04-13 21:47 ` [PATCH nf 1/1] netfilter: cttimeout: Fix one possible use-after-free issue Pablo Neira Ayuso
2017-04-13 22:35 ` Gao Feng
2017-04-13 22:44 ` Pablo Neira Ayuso
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1491476949-92872-1-git-send-email-gfree.wind@foxmail.com \
--to=gfree.wind@foxmail.com \
--cc=fgao@ikuai8.com \
--cc=netfilter-devel@vger.kernel.org \
--cc=pablo@netfilter.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).