[syzbot] WARNING in mbind

syzbot

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Jan 9, 2023, 1:58:45 AM1/9/23

to ak...@linux-foundation.org, linux-...@vger.kernel.org, linu...@kvack.org, syzkall...@googlegroups.com

Hello,

syzbot found the following issue on:

HEAD commit: 543b9b2fe10b Add linux-next specific files for 20230109
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1609b0ce480000
kernel config: https://syzkaller.appspot.com/x/.config?x=ceb6f70a080e19c3
dashboard link: https://syzkaller.appspot.com/bug?extid=502859d610c661e56545
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/22f2428ec2eb/disk-543b9b2f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6003c7af47cc/vmlinux-543b9b2f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ac9a6ad60347/bzImage-543b9b2f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+502859...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 30709 at mm/mempolicy.c:797 mbind_range+0x5d2/0x760 mm/mempolicy.c:797
Modules linked in:
CPU: 0 PID: 30709 Comm: syz-executor.3 Not tainted 6.2.0-rc3-next-20230109-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:mbind_range+0x5d2/0x760 mm/mempolicy.c:797
Code: 96 e8 f2 c7 b4 ff 4d 85 e4 74 8c e8 e8 c7 b4 ff 4c 89 e7 e8 10 7d ff ff e9 7a ff ff ff 45 31 f6 e9 72 ff ff ff e8 ce c7 b4 ff <0f> 0b 45 31 f6 e9 63 ff ff ff e8 bf ae 02 00 e9 6d fc ff ff 4c 89
RSP: 0018:ffffc90003ac7ca8 EFLAGS: 00010216
RAX: 000000000000022c RBX: ffff888075406c00 RCX: ffffc900146ed000
RDX: 0000000000040000 RSI: ffffffff81cce582 RDI: ffffc90003ac7d20
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000020c12000
R13: 0000000000000000 R14: 0000000020012000 R15: 0000000000000000
FS: 00007f0dd0398700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020319000 CR3: 00000000485d1000 CR4: 00000000003506e0
Call Trace:
<TASK>
do_mbind mm/mempolicy.c:1320 [inline]
kernel_mbind+0x473/0x7c0 mm/mempolicy.c:1474
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: 0033:0x7f0dcf68c0c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0dd0398168 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 00007f0dcf7abf80 RCX: 00007f0dcf68c0c9
RDX: 0000000000000000 RSI: 0000000000c00000 RDI: 0000000020012000
RBP: 00007f0dcf6e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdc142a6cf R14: 00007f0dd0398300 R15: 0000000000022000
</TASK>

---
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syzbot

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Jan 9, 2023, 9:15:41 AM1/9/23

to ak...@linux-foundation.org, linux-...@vger.kernel.org, linu...@kvack.org, syzkall...@googlegroups.com

syzbot has found a reproducer for the following issue on:

HEAD commit: 543b9b2fe10b Add linux-next specific files for 20230109
git tree: linux-next

console+strace: https://syzkaller.appspot.com/x/log.txt?x=12978216480000

kernel config: https://syzkaller.appspot.com/x/.config?x=ceb6f70a080e19c3
dashboard link: https://syzkaller.appspot.com/bug?extid=502859d610c661e56545
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117fcc02480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1396d7d6480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/22f2428ec2eb/disk-543b9b2f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6003c7af47cc/vmlinux-543b9b2f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ac9a6ad60347/bzImage-543b9b2f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+502859...@syzkaller.appspotmail.com

------------[ cut here ]------------

WARNING: CPU: 0 PID: 5072 at mm/mempolicy.c:797 mbind_range+0x5d2/0x760 mm/mempolicy.c:797
Modules linked in:
CPU: 0 PID: 5072 Comm: syz-executor326 Not tainted 6.2.0-rc3-next-20230109-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:mbind_range+0x5d2/0x760 mm/mempolicy.c:797
Code: 96 e8 f2 c7 b4 ff 4d 85 e4 74 8c e8 e8 c7 b4 ff 4c 89 e7 e8 10 7d ff ff e9 7a ff ff ff 45 31 f6 e9 72 ff ff ff e8 ce c7 b4 ff <0f> 0b 45 31 f6 e9 63 ff ff ff e8 bf ae 02 00 e9 6d fc ff ff 4c 89

RSP: 0018:ffffc90003c9fca8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88807aa0ec00 RCX: 0000000000000000
RDX: ffff888022cad7c0 RSI: ffffffff81cce582 RDI: ffffc90003c9fd20

RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000020c12000
R13: 0000000000000000 R14: 0000000020012000 R15: 0000000000000000

FS: 00005555556a1300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fba95ca5fb8 CR3: 0000000026945000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Call Trace:
<TASK>
do_mbind mm/mempolicy.c:1320 [inline]
kernel_mbind+0x473/0x7c0 mm/mempolicy.c:1474
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: 0033:0x7fba95c5eae9
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:00007ffe65f13508 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fba95c5eae9

RDX: 0000000000000000 RSI: 0000000000c00000 RDI: 0000000020012000

RBP: 00007fba95c22c90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fba95c22d20
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>

Andrew Morton

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Jan 10, 2023, 4:40:04 AM1/10/23

to syzbot, linux-...@vger.kernel.org, linu...@kvack.org, syzkall...@googlegroups.com, Liam Howlett

On Mon, 09 Jan 2023 06:15:39 -0800 syzbot <syzbot+502859...@syzkaller.appspotmail.com> wrote:

> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 543b9b2fe10b Add linux-next specific files for 20230109
> git tree: linux-next

THanks. Will you be performing a bisection?

> console+strace: https://syzkaller.appspot.com/x/log.txt?x=12978216480000
> kernel config: https://syzkaller.appspot.com/x/.config?x=ceb6f70a080e19c3
> dashboard link: https://syzkaller.appspot.com/bug?extid=502859d610c661e56545
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117fcc02480000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1396d7d6480000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/22f2428ec2eb/disk-543b9b2f.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/6003c7af47cc/vmlinux-543b9b2f.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/ac9a6ad60347/bzImage-543b9b2f.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+502859...@syzkaller.appspotmail.com
>
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 5072 at mm/mempolicy.c:797 mbind_range+0x5d2/0x760 mm/mempolicy.c:797

static int mbind_range(struct mm_struct *mm, unsigned long start,
unsigned long end, struct mempolicy *new_pol)
{
VMA_ITERATOR(vmi, mm, start);
struct vm_area_struct *prev;
struct vm_area_struct *vma;
int err = 0;
pgoff_t pgoff;

prev = vma_prev(&vmi);
vma = vma_find(&vmi, end);
if (WARN_ON(!vma))
return 0;

Liam recently altered this code with "mempolicy: convert to vma iterator"?

Liam Howlett

unread,

Jan 10, 2023, 10:45:34 AM1/10/23

to Andrew Morton, syzbot, linux-...@vger.kernel.org, linu...@kvack.org, syzkall...@googlegroups.com

* Andrew Morton <ak...@linux-foundation.org> [230109 19:02]:

> On Mon, 09 Jan 2023 06:15:39 -0800 syzbot <syzbot+502859...@syzkaller.appspotmail.com> wrote:
>
> > syzbot has found a reproducer for the following issue on:
> >
> > HEAD commit: 543b9b2fe10b Add linux-next specific files for 20230109
> > git tree: linux-next
>
> THanks. Will you be performing a bisection?

[syzbot] WARNING in mbind_range

syzbot

syzbot

Andrew Morton

Liam Howlett