netfilter: nf_conntrack_expect: use expect->helper

Browse source

Use expect->helper in ctnetlink and /proc to dump the helper name.
Using nfct_help() without holding a reference to the master conntrack
is unsafe.

Use exp->master->helper in ctnetlink path if userspace does not provide
an explicit helper when creating an expectation to retain the existing
behaviour. The ctnetlink expectation path holds the reference on the
master conntrack and nf_conntrack_expect lock and the nfnetlink glue
path refers to the master ct that is attached to the skb.

Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

...

This commit is contained in:

Pablo Neira Ayuso 2026-03-25 14:11:03 +01:00

parent 9c42bc9db9

commit f017941060

4 changed files with 13 additions and 21 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

net/netfilter/nf_conntrack_expect.c

View file

6

net/netfilter/nf_conntrack_helper.c

View file

24

net/netfilter/nf_conntrack_netlink.c

View file

2

net/netfilter/nf_conntrack_sip.c

View file