| Message ID | 20241105094823.2403806-1-dmantipov@yandex.ru (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] can: fix skb reference counting in j1939_session_new() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Series ignored based on subject |
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c index 319f47df3330..95f7a7e65a73 100644 --- a/net/can/j1939/transport.c +++ b/net/can/j1939/transport.c @@ -1505,7 +1505,7 @@ static struct j1939_session *j1939_session_new(struct j1939_priv *priv, session->state = J1939_SESSION_NEW; skb_queue_head_init(&session->skb_queue); - skb_queue_tail(&session->skb_queue, skb); + skb_queue_tail(&session->skb_queue, skb_get(skb)); skcb = j1939_skb_to_cb(skb); memcpy(&session->skcb, skcb, sizeof(session->skcb));
Since 'j1939_session_skb_queue()' do an extra 'skb_get()' for each new skb, I assume that the same should be done for an initial one in 'j1939_session_new()' just to avoid refcount underflow. Reported-by: syzbot+d4e8dc385d9258220c31@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d4e8dc385d9258220c31 Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> --- v2: resend after hitting skb refcount underflow once again when looking around https://syzkaller.appspot.com/bug?extid=0e6ddb1ef80986bdfe64 --- net/can/j1939/transport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)