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| author | Liping Zhang <zlpnobody@gmail.com> | 2017-04-02 18:01:33 +0800 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-04-08 23:52:17 +0200 |
| commit | 207df81501021f6d1a935cebf8e1f34d6d25564b (patch) | |
| tree | a64275e3cf253dc9e3ec2b6f0bd635651746fa11 | |
| parent | 0c7930e5763bdd189bd50035c025a9cbe5e82f23 (diff) | |
| download | linux-stable-207df81501021f6d1a935cebf8e1f34d6d25564b.tar.gz linux-stable-207df81501021f6d1a935cebf8e1f34d6d25564b.tar.bz2 linux-stable-207df81501021f6d1a935cebf8e1f34d6d25564b.zip | |
netfilter: ctnetlink: skip dumping expect when nfct_help(ct) is NULL
For IPCTNL_MSG_EXP_GET, if the CTA_EXPECT_MASTER attr is specified, then
the NLM_F_DUMP request will dump the expectations related to this
connection tracking.
But we forget to check whether the conntrack has nf_conn_help or not,
so if nfct_help(ct) is NULL, oops will happen:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: ctnetlink_exp_ct_dump_table+0xf9/0x1e0 [nf_conntrack_netlink]
Call Trace:
? ctnetlink_exp_ct_dump_table+0x75/0x1e0 [nf_conntrack_netlink]
netlink_dump+0x124/0x2a0
__netlink_dump_start+0x161/0x190
ctnetlink_dump_exp_ct+0x16c/0x1bc [nf_conntrack_netlink]
? ctnetlink_exp_fill_info.constprop.33+0xf0/0xf0 [nf_conntrack_netlink]
? ctnetlink_glue_seqadj+0x20/0x20 [nf_conntrack_netlink]
ctnetlink_get_expect+0x32e/0x370 [nf_conntrack_netlink]
? debug_lockdep_rcu_enabled+0x1d/0x20
nfnetlink_rcv_msg+0x60a/0x6a9 [nfnetlink]
? nfnetlink_rcv_msg+0x1b9/0x6a9 [nfnetlink]
[...]
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index f9c643bc1a8e..f78eadba343d 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -2794,6 +2794,12 @@ static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl, return -ENOENT; ct = nf_ct_tuplehash_to_ctrack(h); + /* No expectation linked to this connection tracking. */ + if (!nfct_help(ct)) { + nf_ct_put(ct); + return 0; + } + c.data = ct; err = netlink_dump_start(ctnl, skb, nlh, &c); |