From: Florian Westphal <fw@xxxxxxxxx>
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@xxxxxxxxxxxxxxxxxxxxxxxxx>
Fixes: 78222bacfca9 ("netfilter: cttimeout: decouple unlink and free on netns destruction")
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
net/netfilter/nfnetlink_cttimeout.c | 5 +++--
1 file 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 {
--
2.30.2
