diff options
| author | Florian Westphal | 2022-05-20 00:02:05 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso | 2022-05-27 11:16:38 +0200 |
| commit | aeed55a08d0b2bf2e3986b110b04d2a5aca192a6 (patch) | |
| tree | 46390862220007597bfe6d217b33bd5dfbd371c7 /net | |
| parent | 56b14ecec97f39118bf85c9ac2438c5a949509ed (diff) | |
netfilter: cttimeout: fix slab-out-of-bounds read in cttimeout_net_exit
syzbot reports:
BUG: KASAN: slab-out-of-bounds in __list_del_entry_valid+0xcc/0xf0 lib/list_debug.c:42
[..]
list_del include/linux/list.h:148 [inline]
cttimeout_net_exit+0x211/0x540 net/netfilter/nfnetlink_cttimeout.c:617
No reproducer so far. Looking at recent changes in this area
its clear that the free_head must not be at the end of the
structure because nf_ct_timeout structure has variable size.
Reported-by: <syzbot+92968395eedbdbd3617d@syzkaller.appspotmail.com>
Fixes: 78222bacfca9 ("netfilter: cttimeout: decouple unlink and free on netns destruction")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nfnetlink_cttimeout.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/netfilter/nfnetlink_cttimeout.c b/net/netfilter/nfnetlink_cttimeout.c index f069c24c6146..af15102bc696 100644 --- a/net/netfilter/nfnetlink_cttimeout.c +++ b/net/netfilter/nfnetlink_cttimeout.c @@ -35,12 +35,13 @@ static unsigned int nfct_timeout_id __read_mostly; struct ctnl_timeout { struct list_head head; + struct list_head free_head; struct rcu_head rcu_head; refcount_t refcnt; char name[CTNL_TIMEOUT_NAME_MAX]; - struct nf_ct_timeout timeout; - struct list_head free_head; + /* must be at the end */ + struct nf_ct_timeout timeout; }; struct nfct_timeout_pernet { |