Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:  vsock: Fix memory leak in vmci_transport_recv_dgram_cb()  During the closure of a datagram socket, the vmci_transport_recv_dgram_cb() function may be called, which will add the packets to the socket's backlog; then, after the receive queue is cleared, the __release_sock() function will move the packet back from the socket's backlog to the receive queue, which will lead to a memory leak.  sock_close   __sock_release     __vsock_release       // take ownership by user-space       lock_sock_nested       sock_set_flag(sk, SOCK_DEAD)       vmci_transport_release                                       vmci_dispatch_dgs                                         vmci_datagram_invoke_guest_handler                                           vmci_transport_recv_dgram_cb                                             sk_receive_skb                                               if (!sock_owned_by_user(sk))                                                   [...]                                          (!)  else if sk_add_backlog()                                                   [...]   (!) skb_queue_purge(&sk->sk_receive_queue)        release_sock         __release_sock           // move all packets from the backlog           // to the receive queue    (!)    sk_backlog_rcv             vsock_queue_rcv_skb             [...]               __sock_queue_rcv_skb                 if (!sock_flag(sk, SOCK_DEAD))                   // Since the socket is "dead", the function will not                   // be called                   sk->sk_data_ready(sk)         sock_release_ownership(sk);         sock_put  Add a receive queue cleanup in the socket destructor to fix this.  syzkaller report:  unreferenced object 0xffff8880117bfb80 (size 240):   comm "irq/56-vmw_vmci", pid 205, jiffies 4295064448 (age 73.992s)   hex dump (first 32 bytes):     78 dc 26 1e 80 88 ff ff 78 dc 26 1e 80 88 ff ff  x.&.....x.&.....     00 00 00 00 00 00 00 00 c0 da 26 1e 80 88 ff ff  ..........&.....   backtrace:     [<ffffffff82be8d97>] __alloc_skb+0x287/0x330 net/core/skbuff.c:505     [<ffffffffa114bcbd>] vmci_transport_recv_dgram_cb+0xbd/0x210 [vmw_vsock_vmci_transport]     [<ffffffffa05072c6>] vmci_datagram_invoke_guest_handler+0x366/0x450 [vmw_vmci]     [<ffffffffa050ad75>] vmci_dispatch_dgs+0x235/0x490 [vmw_vmci]     [<ffffffffa050b025>] vmci_interrupt+0x55/0x290 [vmw_vmci]     [<ffffffff8137ad2b>] irq_thread_fn+0x8b/0x1a0 kernel/irq/manage.c:1205     [<ffffffff8137c7ae>] irq_thread+0x28e/0x530 kernel/irq/manage.c:1314     [<ffffffff81253dd6>] kthread+0x2e6/0x3a0 kernel/kthread.c:376     [<ffffffff81004392>] ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:295  Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with Syzkaller.