mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
net/x25: Fix null-ptr-deref in x25_disconnect
commit8999dc8949
upstream. We should check null before do x25_neigh_put in x25_disconnect, otherwise may cause null-ptr-deref like this: #include <sys/socket.h> #include <linux/x25.h> int main() { int sck_x25; sck_x25 = socket(AF_X25, SOCK_SEQPACKET, 0); close(sck_x25); return 0; } BUG: kernel NULL pointer dereference, address: 00000000000000d8 CPU: 0 PID: 4817 Comm: t2 Not tainted 5.7.0-rc3+ #159 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3- RIP: 0010:x25_disconnect+0x91/0xe0 Call Trace: x25_release+0x18a/0x1b0 __sock_release+0x3d/0xc0 sock_close+0x13/0x20 __fput+0x107/0x270 ____fput+0x9/0x10 task_work_run+0x6d/0xb0 exit_to_usermode_loop+0x102/0x110 do_syscall_64+0x23c/0x260 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Reported-by: syzbot+6db548b615e5aeefdce2@syzkaller.appspotmail.com Fixes:4becb7ee5b
("net/x25: Fix x25_neigh refcnt leak when x25 disconnect") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
69cd304cfa
commit
bbb13adb07
1 changed files with 6 additions and 4 deletions
|
@ -357,10 +357,12 @@ void x25_disconnect(struct sock *sk, int reason, unsigned char cause,
|
|||
sk->sk_state_change(sk);
|
||||
sock_set_flag(sk, SOCK_DEAD);
|
||||
}
|
||||
read_lock_bh(&x25_list_lock);
|
||||
x25_neigh_put(x25->neighbour);
|
||||
x25->neighbour = NULL;
|
||||
read_unlock_bh(&x25_list_lock);
|
||||
if (x25->neighbour) {
|
||||
read_lock_bh(&x25_list_lock);
|
||||
x25_neigh_put(x25->neighbour);
|
||||
x25->neighbour = NULL;
|
||||
read_unlock_bh(&x25_list_lock);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
Loading…
Reference in a new issue