sctp: not copy sctp_sock pd_lobby in sctp_copy_descendant
Now sctp_copy_descendant() copies pd_lobby from old sctp scok to new
sctp sock. If sctp_sock_migrate() returns error, it will panic when
releasing new sock and trying to purge pd_lobby due to the incorrect
pointers in pd_lobby.
[ 120.485116] kasan: CONFIG_KASAN_INLINE enabled
[ 120.486270] kasan: GPF could be caused by NULL-ptr deref or user
[ 120.509901] Call Trace:
[ 120.510443] sctp_ulpevent_free+0x1e8/0x490 [sctp]
[ 120.511438] sctp_queue_purge_ulpevents+0x97/0xe0 [sctp]
[ 120.512535] sctp_close+0x13a/0x700 [sctp]
[ 120.517483] inet_release+0xdc/0x1c0
[ 120.518215] __sock_release+0x1d2/0x2a0
[ 120.519025] sctp_do_peeloff+0x30f/0x3c0 [sctp]
We fix it by not copying sctp_sock pd_lobby in sctp_copy_descendan(),
and skb_queue_head_init() can also be removed in sctp_sock_migrate().
Reported-by: syzbot+85e0b422ff140b03672a@syzkaller.appspotmail.com
Fixes: 89664c623617 ("sctp: sctp_sock_migrate() returns error if sctp_bind_addr_dup() fails")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed