2023-03-27 03:46:52

by syzbot

[permalink] [raw]
Subject: [syzbot] linux-next test error: general protection fault in vma_merge

Hello,

syzbot found the following issue on:

HEAD commit: 7c4a254d78f8 Add linux-next specific files for 20230323
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=15f70246c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=20fd034702e6edd2
dashboard link: https://syzkaller.appspot.com/bug?extid=a2fd5af4a33891110a79
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dc0bbbecd2a5/disk-7c4a254d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6b2c8c7cfd4b/vmlinux-7c4a254d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ae312a388585/bzImage-7c4a254d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

general protection fault, probably for non-canonical address 0xdffffc0000000018: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000c0-0x00000000000000c7]
CPU: 1 PID: 5080 Comm: syz-fuzzer Not tainted 6.3.0-rc3-next-20230323-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:vma_merge+0x234/0x1fd0 mm/mmap.c:952
Code: 08 00 0f 84 b0 03 00 00 e8 e9 54 bf ff 48 8b 44 24 08 48 8d b8 a8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4d 18 00 00 48 8b 44 24 08 48 8b b0 a8 00 00 00
RSP: 0018:ffffc90003d0f998 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: ffff88802974b800 RCX: 0000000000000000
RDX: 0000000000000018 RSI: ffffffff81c37957 RDI: 00000000000000c7
RBP: ffff888079aaa400 R08: 0000000000000006 R09: 0000000000000000
R10: 000000c001ffffff R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: 000000c002000000 R15: 0000000000000000
FS: 000000c000524890(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe510676000 CR3: 00000000249a5000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
madvise_update_vma+0x23f/0xd40 mm/madvise.c:153
madvise_vma_behavior+0x7f6/0x20e0 mm/madvise.c:1091
madvise_walk_vmas+0x1c7/0x2b0 mm/madvise.c:1260
do_madvise.part.0+0x193/0x470 mm/madvise.c:1439
do_madvise mm/madvise.c:1452 [inline]
__do_sys_madvise mm/madvise.c:1452 [inline]
__se_sys_madvise mm/madvise.c:1450 [inline]
__x64_sys_madvise+0x117/0x150 mm/madvise.c:1450
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x46b557
Code: 8b 24 24 48 8b 6c 24 10 48 83 c4 18 c3 cc cc cc cc cc cc 48 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 48 c7 c0 1c 00 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc 48 8b 7c 24 08 8b 74 24 10 8b 54 24 14
RSP: 002b:000000c00022de60 EFLAGS: 00000206 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 0000000000a12000 RCX: 000000000046b557
RDX: 000000000000000e RSI: 0000000000800000 RDI: 000000c001c00000
RBP: 000000c00022de88 R08: 0000000000000509 R09: 000000c001b6a000
R10: 00000000000012bd R11: 0000000000000206 R12: 0000000000000509
R13: 0000000000000003 R14: 000000c0003f1a00 R15: 00000000010e0700
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vma_merge+0x234/0x1fd0 mm/mmap.c:952
Code: 08 00 0f 84 b0 03 00 00 e8 e9 54 bf ff 48 8b 44 24 08 48 8d b8 a8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4d 18 00 00 48 8b 44 24 08 48 8b b0 a8 00 00 00
RSP: 0018:ffffc90003d0f998 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: ffff88802974b800 RCX: 0000000000000000
RDX: 0000000000000018 RSI: ffffffff81c37957 RDI: 00000000000000c7
RBP: ffff888079aaa400 R08: 0000000000000006 R09: 0000000000000000
R10: 000000c001ffffff R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: 000000c002000000 R15: 0000000000000000
FS: 000000c000524890(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564702bbb078 CR3: 00000000249a5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 08 00 or %al,(%rax)
2: 0f 84 b0 03 00 00 je 0x3b8
8: e8 e9 54 bf ff callq 0xffbf54f6
d: 48 8b 44 24 08 mov 0x8(%rsp),%rax
12: 48 8d b8 a8 00 00 00 lea 0xa8(%rax),%rdi
19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
20: fc ff df
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 0f 85 4d 18 00 00 jne 0x1881
34: 48 8b 44 24 08 mov 0x8(%rsp),%rax
39: 48 8b b0 a8 00 00 00 mov 0xa8(%rax),%rsi


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email protected].

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.


2023-03-27 08:53:27

by Vlastimil Babka

[permalink] [raw]
Subject: Re: [syzbot] linux-next test error: general protection fault in vma_merge

On 3/27/23 05:40, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 7c4a254d78f8 Add linux-next specific files for 20230323

Known issue already fixed in newer -next.

> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=15f70246c80000
> kernel config: https://syzkaller.appspot.com/x/.config?x=20fd034702e6edd2
> dashboard link: https://syzkaller.appspot.com/bug?extid=a2fd5af4a33891110a79
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/dc0bbbecd2a5/disk-7c4a254d.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/6b2c8c7cfd4b/vmlinux-7c4a254d.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/ae312a388585/bzImage-7c4a254d.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
>
> general protection fault, probably for non-canonical address 0xdffffc0000000018: 0000 [#1] PREEMPT SMP KASAN
> KASAN: null-ptr-deref in range [0x00000000000000c0-0x00000000000000c7]
> CPU: 1 PID: 5080 Comm: syz-fuzzer Not tainted 6.3.0-rc3-next-20230323-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
> RIP: 0010:vma_merge+0x234/0x1fd0 mm/mmap.c:952
> Code: 08 00 0f 84 b0 03 00 00 e8 e9 54 bf ff 48 8b 44 24 08 48 8d b8 a8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4d 18 00 00 48 8b 44 24 08 48 8b b0 a8 00 00 00
> RSP: 0018:ffffc90003d0f998 EFLAGS: 00010207
> RAX: dffffc0000000000 RBX: ffff88802974b800 RCX: 0000000000000000
> RDX: 0000000000000018 RSI: ffffffff81c37957 RDI: 00000000000000c7
> RBP: ffff888079aaa400 R08: 0000000000000006 R09: 0000000000000000
> R10: 000000c001ffffff R11: 0000000000000000 R12: 0000000000000001
> R13: 0000000000000000 R14: 000000c002000000 R15: 0000000000000000
> FS: 000000c000524890(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007fe510676000 CR3: 00000000249a5000 CR4: 00000000003506e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> madvise_update_vma+0x23f/0xd40 mm/madvise.c:153
> madvise_vma_behavior+0x7f6/0x20e0 mm/madvise.c:1091
> madvise_walk_vmas+0x1c7/0x2b0 mm/madvise.c:1260
> do_madvise.part.0+0x193/0x470 mm/madvise.c:1439
> do_madvise mm/madvise.c:1452 [inline]
> __do_sys_madvise mm/madvise.c:1452 [inline]
> __se_sys_madvise mm/madvise.c:1450 [inline]
> __x64_sys_madvise+0x117/0x150 mm/madvise.c:1450
> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
> entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x46b557
> Code: 8b 24 24 48 8b 6c 24 10 48 83 c4 18 c3 cc cc cc cc cc cc 48 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 48 c7 c0 1c 00 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc 48 8b 7c 24 08 8b 74 24 10 8b 54 24 14
> RSP: 002b:000000c00022de60 EFLAGS: 00000206 ORIG_RAX: 000000000000001c
> RAX: ffffffffffffffda RBX: 0000000000a12000 RCX: 000000000046b557
> RDX: 000000000000000e RSI: 0000000000800000 RDI: 000000c001c00000
> RBP: 000000c00022de88 R08: 0000000000000509 R09: 000000c001b6a000
> R10: 00000000000012bd R11: 0000000000000206 R12: 0000000000000509
> R13: 0000000000000003 R14: 000000c0003f1a00 R15: 00000000010e0700
> </TASK>
> Modules linked in:
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:vma_merge+0x234/0x1fd0 mm/mmap.c:952
> Code: 08 00 0f 84 b0 03 00 00 e8 e9 54 bf ff 48 8b 44 24 08 48 8d b8 a8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4d 18 00 00 48 8b 44 24 08 48 8b b0 a8 00 00 00
> RSP: 0018:ffffc90003d0f998 EFLAGS: 00010207
> RAX: dffffc0000000000 RBX: ffff88802974b800 RCX: 0000000000000000
> RDX: 0000000000000018 RSI: ffffffff81c37957 RDI: 00000000000000c7
> RBP: ffff888079aaa400 R08: 0000000000000006 R09: 0000000000000000
> R10: 000000c001ffffff R11: 0000000000000000 R12: 0000000000000001
> R13: 0000000000000000 R14: 000000c002000000 R15: 0000000000000000
> FS: 000000c000524890(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000564702bbb078 CR3: 00000000249a5000 CR4: 00000000003506f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> ----------------
> Code disassembly (best guess):
> 0: 08 00 or %al,(%rax)
> 2: 0f 84 b0 03 00 00 je 0x3b8
> 8: e8 e9 54 bf ff callq 0xffbf54f6
> d: 48 8b 44 24 08 mov 0x8(%rsp),%rax
> 12: 48 8d b8 a8 00 00 00 lea 0xa8(%rax),%rdi
> 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
> 20: fc ff df
> 23: 48 89 fa mov %rdi,%rdx
> 26: 48 c1 ea 03 shr $0x3,%rdx
> * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
> 2e: 0f 85 4d 18 00 00 jne 0x1881
> 34: 48 8b 44 24 08 mov 0x8(%rsp),%rax
> 39: 48 8b b0 a8 00 00 00 mov 0xa8(%rax),%rsi
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at [email protected].
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>