From: Florian Westphal <fw@strlen.de>
To: Bill Fink <billfink@mindspring.com>
Cc: netfilter@vger.kernel.org, netfilter-devel@vger.kernel.org
Subject: Re: conntrackd segfault on EPSV IPv6 ftp command when using ftp ExpectationSync
Date: Fri, 5 Jul 2013 10:19:10 +0200 [thread overview]
Message-ID: <20130705081910.GA25000@breakpoint.cc> (raw)
In-Reply-To: <20130705020312.25783ccd.billfink@mindspring.com>
Bill Fink <billfink@mindspring.com> wrote:
> 230 Anonymous login ok, restrictions apply.
> EPSV
> 229 Entering Extended Passive Mode (|||1584|)
>
> As soon as I enter the EPSV command, I get the following
> conntrackd segfault:
>
> Jul 5 00:41:06 sen-fw1 kernel: [274422.060695] conntrackd[4821]: segfault at 0 ip 000000000040c660 sp 00007fffebb098a8 error 4 in conntrackd[400000+3d000]
#0 0x000000000040f217 in jhash2 (k=0x0, length=4, initval=0) at
../include/jhash.h:99
99 a += k[0];
(gdb) bt f
#0 0x000000000040f217 in jhash2 (k=0x0, length=4, initval=0) at ../include/jhash.h:99
a = 2654435769 b = 2654435769 c = 0 len = 4
#1 0x000000000040f564 in ct_filter_hash6 (data=0x0, table=0x16ef630) at filter.c:57
#2 0x000000000040ad34 in hashtable_hash (table=0x16ef630, data=0x0) at hash.c:63
#3 0x000000000040fd19 in __ct_filter_test_ipv6 (f=0x16eeba0, ct=0x1703760) at filter.c:265
id_src = 51 id_dst = 24051376 src = 0x1703760 dst = 0x0
NULL deref in __ct_filter_test_ipv6. Doesn't happen for ipv4 because
nfct_get_attr_u32() return 0, but nfct_get_attr() returns NULL instead.
@@ -261,8 +264,8 @@ __ct_filter_test_ipv6(struct ct_filter *f, const
struct nf_conntrack *ct)
src = nfct_get_attr(ct, ATTR_ORIG_IPV6_SRC);
dst = nfct_get_attr(ct, ATTR_REPL_IPV6_SRC);
- id_src = hashtable_hash(f->h6, src);
- id_dst = hashtable_hash(f->h6, dst);
+ id_src = src ? hashtable_hash(f->h6, src) : 0;
+ id_dst = dst ? hashtable_hash(f->h6, dst) : 0;
Not sure if this is enough, there are other callers
of nfct_get_attr() that don't check for NULL.
next prev parent reply other threads:[~2013-07-05 8:19 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-05 6:03 conntrackd segfault on EPSV IPv6 ftp command when using ftp ExpectationSync Bill Fink
2013-07-05 8:19 ` Florian Westphal [this message]
2013-07-05 19:45 ` Bill Fink
2013-07-05 23:52 ` Bill Fink
2013-07-06 13:23 ` Pablo Neira Ayuso
2013-07-07 7:04 ` Bill Fink
2013-07-09 5:30 ` Bill Fink
2013-07-09 18:22 ` Pablo Neira Ayuso
2013-07-10 9:58 ` Bill Fink
2013-07-10 22:08 ` Pablo Neira Ayuso
2013-07-11 0:48 ` Pablo Neira Ayuso
2013-07-11 15:19 ` Bill Fink
2013-07-12 7:01 ` Bill Fink
2013-07-15 12:49 ` Pablo Neira Ayuso
2013-07-16 5:55 ` Bill Fink
2013-07-16 21:33 ` Pablo Neira Ayuso
2013-07-16 21:37 ` Pablo Neira Ayuso
2013-07-22 7:00 ` Bill Fink
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