diff options
| author | Michal Luczaj <mhal@rbox.co> | 2025-02-10 13:15:00 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-21 14:11:21 +0100 |
| commit | 94d81870eec7ad2dd7af80bffd314ded26caea1a (patch) | |
| tree | 3b88e49bdf542fded9bb05e00fbb1013174c6e28 | |
| parent | b1afd40321f1c243cffbcf40ea7ca41aca87fa5e (diff) | |
vsock: Orphan socket after transport release
commit 78dafe1cf3afa02ed71084b350713b07e72a18fb upstream.
During socket release, sock_orphan() is called without considering that it
sets sk->sk_wq to NULL. Later, if SO_LINGER is enabled, this leads to a
null pointer dereferenced in virtio_transport_wait_close().
Orphan the socket only after transport release.
Partially reverts the 'Fixes:' commit.
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
lock_acquire+0x19e/0x500
_raw_spin_lock_irqsave+0x47/0x70
add_wait_queue+0x46/0x230
virtio_transport_release+0x4e7/0x7f0
__vsock_release+0xfd/0x490
vsock_release+0x90/0x120
__sock_release+0xa3/0x250
sock_close+0x14/0x20
__fput+0x35e/0xa90
__x64_sys_close+0x78/0xd0
do_syscall_64+0x93/0x1b0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Reported-by: syzbot+9d55b199192a4be7d02c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9d55b199192a4be7d02c
Fixes: fcdd2242c023 ("vsock: Keep the binding until socket destruction")
Tested-by: Luigi Leonardi <leonardi@redhat.com>
Reviewed-by: Luigi Leonardi <leonardi@redhat.com>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250210-vsock-linger-nullderef-v3-1-ef6244d02b54@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/vmw_vsock/af_vsock.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 075695173648..53a081d49d28 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -824,13 +824,19 @@ static void __vsock_release(struct sock *sk, int level) */ lock_sock_nested(sk, level); - sock_orphan(sk); + /* Indicate to vsock_remove_sock() that the socket is being released and + * can be removed from the bound_table. Unlike transport reassignment + * case, where the socket must remain bound despite vsock_remove_sock() + * being called from the transport release() callback. + */ + sock_set_flag(sk, SOCK_DEAD); if (vsk->transport) vsk->transport->release(vsk); else if (sock_type_connectible(sk->sk_type)) vsock_remove_sock(vsk); + sock_orphan(sk); sk->sk_shutdown = SHUTDOWN_MASK; skb_queue_purge(&sk->sk_receive_queue); |