Re: [syzbot] [net?] [virt?] BUG: stack guard page was hit in vsock_bpf_recvmsg

syzbot
2024-08-12T01:37:04Z

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in release_sock

------------[ cut here ]------------
WARNING: CPU: 1 PID: 6092 at include/net/sock.h:1718 sock_release_ownership include/net/sock.h:1718 [inline]
WARNING: CPU: 1 PID: 6092 at include/net/sock.h:1718 release_sock+0x194/0x1f0 net/core/sock.c:3564
Modules linked in:
CPU: 1 UID: 0 PID: 6092 Comm: syz.0.15 Not tainted 6.11.0-rc2-syzkaller-00325-gc4e82c025b3f-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:sock_release_ownership include/net/sock.h:1718 [inline]
RIP: 0010:release_sock+0x194/0x1f0 net/core/sock.c:3564
Code: 01 00 00 00 31 c9 e8 7b 73 f2 f7 eb 05 e8 04 0a 19 f8 4c 89 f7 5b 41 5c 41 5d 41 5e 41 5f 5d e9 32 b9 45 02 e8 ed 09 19 f8 90 <0f> 0b 90 e9 67 ff ff ff e8 df 09 19 f8 4c 89 e7 49 89 db 41 ff d3
RSP: 0018:ffffc9000366fa80 EFLAGS: 00010293
RAX: ffffffff897a6d93 RBX: 0000000000000000 RCX: ffff88801cb81e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 1ffff11005538250 R08: ffffffff897a6cf6 R09: fffff520006cdf40
R10: dffffc0000000000 R11: fffff520006cdf40 R12: ffff88802a9c1080
R13: dffffc0000000000 R14: ffff88802a9c1240 R15: ffff88802a9c1280
FS: 00007f2597b966c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000040 CR3: 00000000229fe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
vsock_connectible_recvmsg+0x7f/0xf0 net/vmw_vsock/af_vsock.c:2308
sock_recvmsg_nosec net/socket.c:1046 [inline]
sock_recvmsg+0x22f/0x280 net/socket.c:1068
____sys_recvmsg+0x1db/0x470 net/socket.c:2816
___sys_recvmsg net/socket.c:2858 [inline]
__sys_recvmsg+0x2f0/0x3e0 net/socket.c:2888
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: 0033:0x7f2596d779f9
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:00007f2597b96038 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f2596f05f80 RCX: 00007f2596d779f9
RDX: 0000000000010042 RSI: 00000000200003c0 RDI: 0000000000000005
RBP: 00007f2596de58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2596f05f80 R15: 00007fff84f29b48
</TASK>

Tested on:

commit: c4e82c02 net: dsa: microchip: ksz9477: split half-dupl..
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=166ef55d980000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8a2eef9745ade09
dashboard link: https://syzkaller.appspot.com/bug?extid=bdb4bd87b5e22058e2a4
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=131902ed980000