• Eric Dumazet's avatar
    virtio/vsock: avoid NULL deref in virtio_transport_seqpacket_allow() · 64295f0d
    Eric Dumazet authored
    Make sure the_virtio_vsock is not NULL before dereferencing it.
    
    general protection fault, probably for non-canonical address 0xdffffc0000000071: 0000 [#1] PREEMPT SMP KASAN
    KASAN: null-ptr-deref in range [0x0000000000000388-0x000000000000038f]
    CPU: 0 PID: 8452 Comm: syz-executor406 Not tainted 5.13.0-rc6-syzkaller #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
    RIP: 0010:virtio_transport_seqpacket_allow+0xbf/0x210 net/vmw_vsock/virtio_transport.c:503
    Code: e8 c6 d9 ab f8 84 db 0f 84 0f 01 00 00 e8 09 d3 ab f8 48 8d bd 88 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 2a 01 00 00 44 0f b6 a5 88 03 00 00
    RSP: 0018:ffffc90003757c18 EFLAGS: 00010206
    RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000000
    RDX: 0000000000000071 RSI: ffffffff88c908e7 RDI: 0000000000000388
    RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
    R10: ffffffff88c90a06 R11: 0000000000000000 R12: 0000000000000000
    R13: ffffffff88c90840 R14: 0000000000000000 R15: 0000000000000001
    FS:  0000000001bee300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000020000082 CR3: 000000002847e000 CR4: 00000000001506f0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     vsock_assign_transport+0x575/0x700 net/vmw_vsock/af_vsock.c:490
     vsock_connect+0x200/0xc00 net/vmw_vsock/af_vsock.c:1337
     __sys_connect_file+0x155/0x1a0 net/socket.c:1824
     __sys_connect+0x161/0x190 net/socket.c:1841
     __do_sys_connect net/socket.c:1851 [inline]
     __se_sys_connect net/socket.c:1848 [inline]
     __x64_sys_connect+0x6f/0xb0 net/socket.c:1848
     do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
     entry_SYSCALL_64_after_hwframe+0x44/0xae
    RIP: 0033:0x43ee69
    Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
    RSP: 002b:00007ffd49e7c788 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
    RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ee69
    RDX: 0000000000000010 RSI: 0000000020000080 RDI: 0000000000000003
    RBP: 0000000000402e50 R08: 0000000000000000 R09: 0000000000400488
    R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402ee0
    R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488
    
    Fixes: 53efbba1 ("virtio/vsock: enable SEQPACKET for transport")
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Cc: Arseny Krasnov <arseny.krasnov@kaspersky.com>
    Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
    Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    64295f0d
virtio_transport.c 18.7 KB