mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

Revert "netfilter: conntrack: fix bug in for_each_sctp_chunk" 

There is no bug.  If sch->length == 0, this would result in an infinite
loop, but first caller, do_basic_checks(), errors out in this case.

After this change, packets with bogus zero-length chunks are no longer
detected as invalid, so revert & add comment wrt. 0 length check.

Fixes: 98ee007745 ("netfilter: conntrack: fix bug in for_each_sctp_chunk")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2023-01-26 02:35:21 +01:00 committed by Pablo Neira Ayuso
parent 2b272bb558
commit bd0e06f0de
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
net/netfilter/nf_conntrack_proto_sctp.c
View File

@ -142,10 +142,11 @@ static void sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
}
#endif
/* do_basic_checks ensures sch->length > 0, do not use before */
#define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \
for ((offset) = (dataoff) + sizeof(struct sctphdr), (count) = 0; \
((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))) && \
(sch)->length; \
(offset) < (skb)->len && \
((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \
(offset) += (ntohs((sch)->length) + 3) & ~3, (count)++)
/* Some validity checks to make sure the chunks are fine */