[syzbot] [mm?] kernel BUG in free_unref_page_prepare

[syzbot] [mm?] kernel BUG in free_unref_page_prepare

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    7271b2a53042 Add linux-next specific files for 20230818
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=119dbe4ba80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1936af09cdef7dd6
dashboard link: https://syzkaller.appspot.com/bug?extid=7423f066b632d9ff23d5
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=112386f3a80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15044717a80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d81109bc02c1/disk-7271b2a5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4b3bf8e2a4f7/vmlinux-7271b2a5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6404cd473c1e/bzImage-7271b2a5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7423f066b632d9ff23d5@syzkaller.appspotmail.com

 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline]
 __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:86
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1136 [inline]
 free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2348
 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2441
 free_contig_range+0xb6/0x190 mm/page_alloc.c:6391
 destroy_args+0x768/0x990 mm/debug_vm_pgtable.c:1028
 debug_vm_pgtable+0x1d7e/0x3e00 mm/debug_vm_pgtable.c:1408
 do_one_initcall+0x117/0x630 init/main.c:1232
 do_initcall_level init/main.c:1294 [inline]
 do_initcalls init/main.c:1310 [inline]
 do_basic_setup init/main.c:1329 [inline]
 kernel_init_freeable+0x5c2/0x900 init/main.c:1547
 kernel_init+0x1c/0x2a0 init/main.c:1437
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:1107!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5045 Comm: syz-executor350 Not tainted 6.5.0-rc6-next-20230818-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:free_pages_prepare mm/page_alloc.c:1107 [inline]
RIP: 0010:free_unref_page_prepare+0x885/0xa40 mm/page_alloc.c:2348
Code: 48 89 d7 e8 5d 2e f4 ff 0f 0b c7 44 24 08 00 00 00 00 4d 8d 77 40 e9 79 fd ff ff 48 c7 c6 80 b9 99 8a 4c 89 ff e8 3b 2e f4 ff <0f> 0b 48 89 ef e8 81 db 0b 00 e9 aa f7 ff ff 4c 89 f7 e8 74 db 0b
RSP: 0018:ffffc9000397f6c0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 0000000000000000
RDX: ffff88807af30000 RSI: ffffffff81d178f5 RDI: 0000000000000000
RBP: ffffea0001b10008 R08: 0000000000000000 R09: fffffbfff1d9bbf2
R10: ffffffff8ecddf97 R11: 1ffffffff1976ca9 R12: 000000000006c400
R13: 0000000000000009 R14: ffffea0001b10040 R15: ffffea0001b10000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f154f89164c CR3: 0000000029448000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2441
 __update_and_free_hugetlb_folio+0x3c1/0x4a0 mm/hugetlb.c:1765
 update_and_free_hugetlb_folio+0x82/0x120 mm/hugetlb.c:1821
 free_huge_folio+0x6e0/0xbb0 mm/hugetlb.c:1917
 release_pages+0x51b/0x14e0 mm/swap.c:1008
 __folio_batch_release+0x77/0xe0 mm/swap.c:1062
 folio_batch_release include/linux/pagevec.h:83 [inline]
 remove_inode_hugepages+0xb7b/0xe20 fs/hugetlbfs/inode.c:691
 hugetlbfs_evict_inode+0x22/0x70 fs/hugetlbfs/inode.c:703
 evict+0x2ed/0x6b0 fs/inode.c:664
 iput_final fs/inode.c:1775 [inline]
 iput.part.0+0x55e/0x7a0 fs/inode.c:1801
 iput+0x5c/0x80 fs/inode.c:1791
 dentry_unlink_inode+0x292/0x430 fs/dcache.c:401
 __dentry_kill+0x3b8/0x640 fs/dcache.c:607
 dentry_kill fs/dcache.c:733 [inline]
 dput+0x8dd/0xfd0 fs/dcache.c:913
 __fput+0x536/0xa70 fs/file_table.c:392
 task_work_run+0x14d/0x240 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa99/0x2a20 kernel/exit.c:874
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
 __do_sys_exit_group kernel/exit.c:1035 [inline]
 __se_sys_exit_group kernel/exit.c:1033 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f154f8c0b09
Code: Unable to access opcode bytes at 0x7f154f8c0adf.
RSP: 002b:00007fffeb55e118 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f154f8c0b09
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007f154f93b290 R08: ffffffffffffffb8 R09: 0000000000000000
R10: 0000000000048031 R11: 0000000000000246 R12: 00007f154f93b290
R13: 0000000000000000 R14: 00007f154f93bce0 R15: 00007f154f891d60
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:free_pages_prepare mm/page_alloc.c:1107 [inline]
RIP: 0010:free_unref_page_prepare+0x885/0xa40 mm/page_alloc.c:2348
Code: 48 89 d7 e8 5d 2e f4 ff 0f 0b c7 44 24 08 00 00 00 00 4d 8d 77 40 e9 79 fd ff ff 48 c7 c6 80 b9 99 8a 4c 89 ff e8 3b 2e f4 ff <0f> 0b 48 89 ef e8 81 db 0b 00 e9 aa f7 ff ff 4c 89 f7 e8 74 db 0b
RSP: 0018:ffffc9000397f6c0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 0000000000000000
RDX: ffff88807af30000 RSI: ffffffff81d178f5 RDI: 0000000000000000
RBP: ffffea0001b10008 R08: 0000000000000000 R09: fffffbfff1d9bbf2
R10: ffffffff8ecddf97 R11: 1ffffffff1976ca9 R12: 000000000006c400
R13: 0000000000000009 R14: ffffea0001b10040 R15: ffffea0001b10000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d22c54e0b8 CR3: 0000000029448000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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Re: [syzbot] [mm?] kernel BUG in free_unref_page_prepare

[Mike Kravetz]

On 08/22/23 02:39, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    7271b2a53042 Add linux-next specific files for 20230818
> git tree:       linux-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=119dbe4ba80000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=1936af09cdef7dd6
> dashboard link: https://syzkaller.appspot.com/bug?extid=7423f066b632d9ff23d5
> compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=112386f3a80000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15044717a80000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/d81109bc02c1/disk-7271b2a5.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/4b3bf8e2a4f7/vmlinux-7271b2a5.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/6404cd473c1e/bzImage-7271b2a5.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7423f066b632d9ff23d5@syzkaller.appspotmail.com

Looks to be caused by Matthew's series "Remove _folio_dtor and _folio_order"
It has already been noted that this series caused issues.

-- 
Mike Kravetz

Re: [syzbot] [mm?] kernel BUG in free_unref_page_prepare

[syzbot]

syzbot has bisected this issue to:

commit 3a77b282e256d880791a4c5aa10ede13d6417425
Author: Matthew Wilcox (Oracle) <willy@infradead.org>
Date:   Wed Aug 16 15:11:58 2023 +0000

    mm: free up a word in the first tail page

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=13297387a80000
start commit:   7271b2a53042 Add linux-next specific files for 20230818
git tree:       linux-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=10a97387a80000
console output: https://syzkaller.appspot.com/x/log.txt?x=17297387a80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1936af09cdef7dd6
dashboard link: https://syzkaller.appspot.com/bug?extid=7423f066b632d9ff23d5
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=112386f3a80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15044717a80000

Reported-by: syzbot+7423f066b632d9ff23d5@syzkaller.appspotmail.com
Fixes: 3a77b282e256 ("mm: free up a word in the first tail page")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection