In the Linux kernel, the following vulnerability has been resolved:

vsock: Orphan socket after transport release

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

https://git.kernel.org/stable/c/3a866f8376f0a5c848dcb59cd26df845fffbe6d8

https://git.kernel.org/stable/c/78dafe1cf3afa02ed71084b350713b07e72a18fb

https://git.kernel.org/stable/c/94d81870eec7ad2dd7af80bffd314ded26caea1a

https://git.kernel.org/stable/c/f3b8e9d3414b2eb083d8293be25a949fe480897b