[syzbot] [net?] [virt?] general protection fault in vsock_stream_has_data

syzbot
2025-01-14T14:48:25Z

Hello,

syzbot found the following issue on:

HEAD commit: 25cc469d6d34 net: phy: micrel: use helper phy_disable_eee
git tree: net-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15faeef8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d50f1d63eac02308
dashboard link: https://syzkaller.appspot.com/bug?extid=71613b464c8ef17ab718
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16e374b0580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1778d3c4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1a1fa1071012/disk-25cc469d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3fcf28733f5e/vmlinux-25cc469d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ed476a847c4e/bzImage-25cc469d.xz

The issue was bisected to:

commit 71dc9ec9ac7d3eee785cdc986c3daeb821381e20
Author: Bobby Eshleman <bobby.eshleman@bytedance.com>
Date: Fri Jan 13 22:21:37 2023 +0000

virtio/vsock: replace virtio_vsock_pkt with sk_buff

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=102b1ef8580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=122b1ef8580000
console output: https://syzkaller.appspot.com/x/log.txt?x=142b1ef8580000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+71613b464c8ef17ab718@syzkaller.appspotmail.com
Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff")

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 0 UID: 0 PID: 8 Comm: kworker/0:0 Not tainted 6.13.0-rc6-syzkaller-00898-g25cc469d6d34 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: vsock-loopback vsock_loopback_work
RIP: 0010:vsock_stream_has_data+0x46/0x70 net/vmw_vsock/af_vsock.c:873
Code: 8d 9e 50 05 00 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 58 82 5c f6 48 8b 1b 48 83 c3 60 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 3b 82 5c f6 4c 8b 1b 4c 89 f7 5b
RSP: 0018:ffffc900000d7748 EFLAGS: 00010206
RAX: 000000000000000c RBX: 0000000000000060 RCX: ffff88801cac5a00
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888077bf08c0
RBP: ffff888077bf08c0 R08: ffff888077bf0927 R09: 1ffff1100ef7e124
R10: dffffc0000000000 R11: ffffed100ef7e125 R12: dffffc0000000000
R13: ffffffff8ffeb820 R14: ffff888077bf08c0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffca709b000 CR3: 000000007b69c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
virtio_transport_do_close+0x64/0x3d0 net/vmw_vsock/virtio_transport_common.c:1214
virtio_transport_recv_disconnecting net/vmw_vsock/virtio_transport_common.c:1452 [inline]
virtio_transport_recv_pkt+0x1755/0x2b10 net/vmw_vsock/virtio_transport_common.c:1661
vsock_loopback_work+0x3e9/0x530 net/vmw_vsock/vsock_loopback.c:133
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vsock_stream_has_data+0x46/0x70 net/vmw_vsock/af_vsock.c:873
Code: 8d 9e 50 05 00 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 58 82 5c f6 48 8b 1b 48 83 c3 60 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 3b 82 5c f6 4c 8b 1b 4c 89 f7 5b
RSP: 0018:ffffc900000d7748 EFLAGS: 00010206
RAX: 000000000000000c RBX: 0000000000000060 RCX: ffff88801cac5a00
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888077bf08c0
RBP: ffff888077bf08c0 R08: ffff888077bf0927 R09: 1ffff1100ef7e124
R10: dffffc0000000000 R11: ffffed100ef7e125 R12: dffffc0000000000
R13: ffffffff8ffeb820 R14: ffff888077bf08c0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffca709b000 CR3: 00000000334b6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 8d 9e 50 05 00 00 lea 0x550(%rsi),%ebx
6: 48 89 d8 mov %rbx,%rax
9: 48 c1 e8 03 shr $0x3,%rax
d: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1)
12: 74 08 je 0x1c
14: 48 89 df mov %rbx,%rdi
17: e8 58 82 5c f6 call 0xf65c8274
1c: 48 8b 1b mov (%rbx),%rbx
1f: 48 83 c3 60 add $0x60,%rbx
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 3b 82 5c f6 call 0xf65c8274
39: 4c 8b 1b mov (%rbx),%r11
3c: 4c 89 f7 mov %r14,%rdi
3f: 5b pop %rbx

---
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