| Message ID | 20241022134819.1085254-1-edumazet@google.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next] vsock: do not leave dangling sk pointer in vsock_create() | expand |
From: Eric Dumazet <edumazet@google.com> Date: Tue, 22 Oct 2024 13:48:19 +0000 > syzbot was able to trigger the following warning after recent > core network cleanup. > > On error vsock_create() frees the allocated sk object, but sock_init_data() > has already attached it to the provided sock object. > > We must clear sock->sk to avoid possible use-after-free later. > > WARNING: CPU: 0 PID: 5282 at net/socket.c:1581 __sock_create+0x897/0x950 net/socket.c:1581 > Modules linked in: > CPU: 0 UID: 0 PID: 5282 Comm: syz.2.43 Not tainted 6.12.0-rc2-syzkaller-00667-g53bac8330865 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 > RIP: 0010:__sock_create+0x897/0x950 net/socket.c:1581 > Code: 7f 06 01 65 48 8b 34 25 00 d8 03 00 48 81 c6 b0 08 00 00 48 c7 c7 60 0b 0d 8d e8 d4 9a 3c 02 e9 11 f8 ff ff e8 0a ab 0d f8 90 <0f> 0b 90 e9 82 fd ff ff 89 e9 80 e1 07 fe c1 38 c1 0f 8c c7 f8 ff > RSP: 0018:ffffc9000394fda8 EFLAGS: 00010293 > RAX: ffffffff89873c46 RBX: ffff888079f3c818 RCX: ffff8880314b9e00 > RDX: 0000000000000000 RSI: 00000000ffffffed RDI: 0000000000000000 > RBP: ffffffff8d3337f0 R08: ffffffff8987384e R09: ffffffff8989473a > R10: dffffc0000000000 R11: fffffbfff203a276 R12: 00000000ffffffed > R13: ffff888079f3c8c0 R14: ffffffff898736e7 R15: dffffc0000000000 > FS: 00005555680ab500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f22b11196d0 CR3: 00000000308c0000 CR4: 00000000003526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > sock_create net/socket.c:1632 [inline] > __sys_socket_create net/socket.c:1669 [inline] > __sys_socket+0x150/0x3c0 net/socket.c:1716 > __do_sys_socket net/socket.c:1730 [inline] > __se_sys_socket net/socket.c:1728 [inline] > __x64_sys_socket+0x7a/0x90 net/socket.c:1728 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7f22b117dff9 > Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007fff56aec0e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 > RAX: ffffffffffffffda RBX: 00007f22b1335f80 RCX: 00007f22b117dff9 > RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000028 > RBP: 00007f22b11f0296 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 00007f22b1335f80 R14: 00007f22b1335f80 R15: 00000000000012dd > > Fixes: 48156296a08c ("net: warn, if pf->create does not clear sock->sk on error") > Reported-by: syzbot <syzkaller@googlegroups.com> > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Ignat Korchagin <ignat@cloudflare.com> > Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Thanks! > --- > net/vmw_vsock/af_vsock.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c > index 35681adedd9aaec3565495158f5342b8aa76c9bc..109b7a0bd0714c9a2d5c9dd58421e7e9344a8474 100644 > --- a/net/vmw_vsock/af_vsock.c > +++ b/net/vmw_vsock/af_vsock.c > @@ -2417,6 +2417,7 @@ static int vsock_create(struct net *net, struct socket *sock, > if (sock->type == SOCK_DGRAM) { > ret = vsock_assign_transport(vsk, NULL); > if (ret < 0) { > + sock->sk = NULL; > sock_put(sk); > return ret; > } > -- > 2.47.0.105.g07ac214952-goog
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 35681adedd9aaec3565495158f5342b8aa76c9bc..109b7a0bd0714c9a2d5c9dd58421e7e9344a8474 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -2417,6 +2417,7 @@ static int vsock_create(struct net *net, struct socket *sock, if (sock->type == SOCK_DGRAM) { ret = vsock_assign_transport(vsk, NULL); if (ret < 0) { + sock->sk = NULL; sock_put(sk); return ret; }
syzbot was able to trigger the following warning after recent core network cleanup. On error vsock_create() frees the allocated sk object, but sock_init_data() has already attached it to the provided sock object. We must clear sock->sk to avoid possible use-after-free later. WARNING: CPU: 0 PID: 5282 at net/socket.c:1581 __sock_create+0x897/0x950 net/socket.c:1581 Modules linked in: CPU: 0 UID: 0 PID: 5282 Comm: syz.2.43 Not tainted 6.12.0-rc2-syzkaller-00667-g53bac8330865 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__sock_create+0x897/0x950 net/socket.c:1581 Code: 7f 06 01 65 48 8b 34 25 00 d8 03 00 48 81 c6 b0 08 00 00 48 c7 c7 60 0b 0d 8d e8 d4 9a 3c 02 e9 11 f8 ff ff e8 0a ab 0d f8 90 <0f> 0b 90 e9 82 fd ff ff 89 e9 80 e1 07 fe c1 38 c1 0f 8c c7 f8 ff RSP: 0018:ffffc9000394fda8 EFLAGS: 00010293 RAX: ffffffff89873c46 RBX: ffff888079f3c818 RCX: ffff8880314b9e00 RDX: 0000000000000000 RSI: 00000000ffffffed RDI: 0000000000000000 RBP: ffffffff8d3337f0 R08: ffffffff8987384e R09: ffffffff8989473a R10: dffffc0000000000 R11: fffffbfff203a276 R12: 00000000ffffffed R13: ffff888079f3c8c0 R14: ffffffff898736e7 R15: dffffc0000000000 FS: 00005555680ab500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f22b11196d0 CR3: 00000000308c0000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> sock_create net/socket.c:1632 [inline] __sys_socket_create net/socket.c:1669 [inline] __sys_socket+0x150/0x3c0 net/socket.c:1716 __do_sys_socket net/socket.c:1730 [inline] __se_sys_socket net/socket.c:1728 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1728 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f22b117dff9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff56aec0e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007f22b1335f80 RCX: 00007f22b117dff9 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000028 RBP: 00007f22b11f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f22b1335f80 R14: 00007f22b1335f80 R15: 00000000000012dd Fixes: 48156296a08c ("net: warn, if pf->create does not clear sock->sk on error") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ignat Korchagin <ignat@cloudflare.com> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> --- net/vmw_vsock/af_vsock.c | 1 + 1 file changed, 1 insertion(+)