linux-kernel - Re: kernel BUG in set_state

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Date:   Mon, 14 Aug 2023 17:31:41 +0800
From:   Qu Wenruo <quwenruo.btrfs@....com>
To:     Yikebaer Aizezi <yikebaer61@...il.com>, clm@...com,
        dsterba@...e.com, josef@...icpanda.com, linux-btrfs@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org
Subject: Re: kernel BUG in set_state_bits



On 2023/8/14 14:23, Yikebaer Aizezi wrote:
> Hello,
>
> When using Healer to fuzz the Linux-6.5-rc5,  the following crash
> was triggered.
>
> HEAD commit: 52a93d39b17dc7eb98b6aa3edb93943248e03b2f (tag: v6.5-rc5)
> git tree: upstream
>
> console output:
> https://drive.google.com/file/d/1KuE7x7TW_pt_aNWWr2GAdehfYixsgeOO/view?usp=drive_link
> kernel config:https://drive.google.com/file/d/1b_em6R2Zl98np83b818BzE1FrxbiaGuh/view?usp=drive_link
> C reproducer:https://drive.google.com/file/d/1HlzFbWr3wqzlLi8I2_ZCQumS71WDLXj1/view?usp=drive_link
> Syzlang reproducer:
> https://drive.google.com/file/d/1Bu70LrWxOzsbkilELLuxo8VnjcAFiH1Y/view?usp=drive_link
>
> If you fix this issue, please add the following tag to the commit:
> Reported-by: Yikebaer Aizezi <yikebaer61@...il.com>
>
>
> memfd_create() without MFD_EXEC nor MFD_NOEXEC_SEAL, pid=8428 'syz-executor'
> loop1: detected capacity change from 0 to 32768
> BTRFS: device fsid 84eb0a0b-d357-4bc1-8741-9d3223c15974 devid 1
> transid 7 /dev/loop1 scanned by syz-executor (8428)
> BTRFS info (device loop1): using xxhash64 (xxhash64-generic) checksum algorithm
> BTRFS info (device loop1): disk space caching is enabled
> BTRFS info (device loop1): enabling ssd optimizations
> BTRFS info (device loop1): auto enabling async discard
> FAULT_INJECTION: forcing a failure.
> name failslab, interval 1, probability 0, space 0, times 1
> CPU: 0 PID: 8428 Comm: syz-executor Not tainted 6.5.0-rc5 #1
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
> Call Trace:
>   <TASK>
>   __dump_stack lib/dump_stack.c:88 [inline]
>   dump_stack_lvl+0x132/0x150 lib/dump_stack.c:106
>   fail_dump lib/fault-inject.c:52 [inline]
>   should_fail_ex+0x49f/0x5b0 lib/fault-inject.c:153
>   should_failslab+0x5/0x10 mm/slab_common.c:1471
>   slab_pre_alloc_hook mm/slab.h:711 [inline]
>   slab_alloc_node mm/slub.c:3452 [inline]
>   __kmem_cache_alloc_node+0x61/0x350 mm/slub.c:3509
>   kmalloc_trace+0x22/0xd0 mm/slab_common.c:1076
>   kmalloc include/linux/slab.h:582 [inline]
>   ulist_add_merge fs/btrfs/ulist.c:210 [inline]
>   ulist_add_merge+0x16f/0x660 fs/btrfs/ulist.c:198
>   add_extent_changeset fs/btrfs/extent-io-tree.c:191 [inline]

If you checked the call site, it is doing GFP_ATOMIC allocation inside a
critical section.

Doing such error injection without any clue is not really helping here.
You can even inject error to NOFAIL call sites, and everyone would not
really treat it serious.

IIRC even syzbot is no longer reporting errors with blind error
injection anymore.

Thanks,
Qu
>   add_extent_changeset fs/btrfs/extent-io-tree.c:178 [inline]
>   set_state_bits.isra.0+0x11f/0x1c0 fs/btrfs/extent-io-tree.c:378
>   insert_state_fast fs/btrfs/extent-io-tree.c:437 [inline]
>   __set_extent_bit+0x418/0x15b0 fs/btrfs/extent-io-tree.c:1034
>   set_record_extent_bits+0x53/0x90 fs/btrfs/extent-io-tree.c:1705
>   qgroup_reserve_data+0x233/0xa80 fs/btrfs/qgroup.c:3800
>   btrfs_qgroup_reserve_data+0x2b/0xc0 fs/btrfs/qgroup.c:3843
>   btrfs_check_data_free_space+0x114/0x290 fs/btrfs/delalloc-space.c:154
>   btrfs_buffered_write+0x4ec/0x1330 fs/btrfs/file.c:1250
>   btrfs_do_write_iter+0xb75/0x11c0 fs/btrfs/file.c:1670
>   call_write_iter include/linux/fs.h:1877 [inline]
>   new_sync_write fs/read_write.c:491 [inline]
>   vfs_write+0x989/0xdb0 fs/read_write.c:584
>   ksys_pwrite64 fs/read_write.c:699 [inline]
>   __do_sys_pwrite64 fs/read_write.c:709 [inline]
>   __se_sys_pwrite64 fs/read_write.c:706 [inline]
>   __x64_sys_pwrite64+0x1ef/0x240 fs/read_write.c:706
>   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>   do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>   entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x47959d
> Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 b4 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f4717e0f068 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
> RAX: ffffffffffffffda RBX: 000000000059c0a0 RCX: 000000000047959d
> RDX: 0000000000000027 RSI: 0000000020005840 RDI: 0000000000000003
> RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000246 R12: 000000000059c0ac
> R13: 000000000000000b R14: 0000000000437250 R15: 00007f4717def000
>   </TASK>
> ------------[ cut here ]------------
> kernel BUG at fs/btrfs/extent-io-tree.c:379!
> invalid opcode: 0000 [#1] PREEMPT SMP KASAN
> CPU: 0 PID: 8428 Comm: syz-executor Not tainted 6.5.0-rc5 #1
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
> RIP: 0010:set_state_bits.isra.0+0x17b/0x1c0 fs/btrfs/extent-io-tree.c:379
> Code: 38 d0 7c 04 84 d2 75 31 44 8b 73 7c e8 be 72 f7 fd 44 89 e0 44
> 09 f0 89 43 7c 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a5 72 f7 fd <0f> 0b
> 4c 89 ef e8 8b 3d 47 fe e9 e6 fe ff ff 4c 89 ef e8 7e 3d 47
> RSP: 0018:ffffc9000675f850 EFLAGS: 00010212
> RAX: 000000000003f702 RBX: ffff88802100cc00 RCX: ffffc90002e49000
> RDX: 0000000000040000 RSI: ffffffff8388e7eb RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
> R10: 00000000fffffff4 R11: 0000000032343854 R12: 0000000000000800
> R13: ffff88802100cc7c R14: 0000000000000fff R15: 0000000000000000
> FS:  00007f4717e0f640(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000505c10 CR3: 0000000018d77000 CR4: 0000000000750ef0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> PKRU: 55555554
> Call Trace:
>   <TASK>
>   insert_state_fast fs/btrfs/extent-io-tree.c:437 [inline]
>   __set_extent_bit+0x418/0x15b0 fs/btrfs/extent-io-tree.c:1034
>   set_record_extent_bits+0x53/0x90 fs/btrfs/extent-io-tree.c:1705
>   qgroup_reserve_data+0x233/0xa80 fs/btrfs/qgroup.c:3800
>   btrfs_qgroup_reserve_data+0x2b/0xc0 fs/btrfs/qgroup.c:3843
>   btrfs_check_data_free_space+0x114/0x290 fs/btrfs/delalloc-space.c:154
>   btrfs_buffered_write+0x4ec/0x1330 fs/btrfs/file.c:1250
>   btrfs_do_write_iter+0xb75/0x11c0 fs/btrfs/file.c:1670
>   call_write_iter include/linux/fs.h:1877 [inline]
>   new_sync_write fs/read_write.c:491 [inline]
>   vfs_write+0x989/0xdb0 fs/read_write.c:584
>   ksys_pwrite64 fs/read_write.c:699 [inline]
>   __do_sys_pwrite64 fs/read_write.c:709 [inline]
>   __se_sys_pwrite64 fs/read_write.c:706 [inline]
>   __x64_sys_pwrite64+0x1ef/0x240 fs/read_write.c:706
>   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>   do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>   entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x47959d
> Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 b4 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f4717e0f068 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
> RAX: ffffffffffffffda RBX: 000000000059c0a0 RCX: 000000000047959d
> RDX: 0000000000000027 RSI: 0000000020005840 RDI: 0000000000000003
> RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000246 R12: 000000000059c0ac
> R13: 000000000000000b R14: 0000000000437250 R15: 00007f4717def000
>   </TASK>
> Modules linked in:
> Dumping ftrace buffer:
>     (ftrace buffer empty)
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:set_state_bits.isra.0+0x17b/0x1c0 fs/btrfs/extent-io-tree.c:379
> Code: 38 d0 7c 04 84 d2 75 31 44 8b 73 7c e8 be 72 f7 fd 44 89 e0 44
> 09 f0 89 43 7c 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a5 72 f7 fd <0f> 0b
> 4c 89 ef e8 8b 3d 47 fe e9 e6 fe ff ff 4c 89 ef e8 7e 3d 47
> RSP: 0018:ffffc9000675f850 EFLAGS: 00010212
> RAX: 000000000003f702 RBX: ffff88802100cc00 RCX: ffffc90002e49000
> RDX: 0000000000040000 RSI: ffffffff8388e7eb RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
> R10: 00000000fffffff4 R11: 0000000032343854 R12: 0000000000000800
> R13: ffff88802100cc7c R14: 0000000000000fff R15: 0000000000000000
> FS:  00007f4717e0f640(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000505c10 CR3: 0000000018d77000 CR4: 0000000000750ef0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> PKRU: 55555554
>
>
> invalid opcode: 0000 [#1] PREEMPT SMP KASAN
> CPU: 0 PID: 8428 Comm: syz-executor Not tainted 6.5.0-rc5 #1
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
> RIP: 0010:set_state_bits.isra.0+0x17b/0x1c0 fs/btrfs/extent-io-tree.c:379
> Code: 38 d0 7c 04 84 d2 75 31 44 8b 73 7c e8 be 72 f7 fd 44 89 e0 44
> 09 f0 89 43 7c 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a5 72 f7 fd <0f> 0b
> 4c 89 ef e8 8b 3d 47 fe e9 e6 fe ff ff 4c 89 ef e8 7e 3d 47
> RSP: 0018:ffffc9000675f850 EFLAGS: 00010212
> RAX: 000000000003f702 RBX: ffff88802100cc00 RCX: ffffc90002e49000
> RDX: 0000000000040000 RSI: ffffffff8388e7eb RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
> R10: 00000000fffffff4 R11: 0000000032343854 R12: 0000000000000800
> R13: ffff88802100cc7c R14: 0000000000000fff R15: 0000000000000000
> FS:  00007f4717e0f640(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000505c10 CR3: 0000000018d77000 CR4: 0000000000750ef0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> PKRU: 55555554
> Call Trace:
>   <TASK>
>   insert_state_fast fs/btrfs/extent-io-tree.c:437 [inline]
>   __set_extent_bit+0x418/0x15b0 fs/btrfs/extent-io-tree.c:1034
>   set_record_extent_bits+0x53/0x90 fs/btrfs/extent-io-tree.c:1705
>   qgroup_reserve_data+0x233/0xa80 fs/btrfs/qgroup.c:3800
>   btrfs_qgroup_reserve_data+0x2b/0xc0 fs/btrfs/qgroup.c:3843
>   btrfs_check_data_free_space+0x114/0x290 fs/btrfs/delalloc-space.c:154
>   btrfs_buffered_write+0x4ec/0x1330 fs/btrfs/file.c:1250
>   btrfs_do_write_iter+0xb75/0x11c0 fs/btrfs/file.c:1670
>   call_write_iter include/linux/fs.h:1877 [inline]
>   new_sync_write fs/read_write.c:491 [inline]
>   vfs_write+0x989/0xdb0 fs/read_write.c:584
>   ksys_pwrite64 fs/read_write.c:699 [inline]
>   __do_sys_pwrite64 fs/read_write.c:709 [inline]
>   __se_sys_pwrite64 fs/read_write.c:706 [inline]
>   __x64_sys_pwrite64+0x1ef/0x240 fs/read_write.c:706
>   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>   do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>   entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x47959d
> Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 b4 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f4717e0f068 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
> RAX: ffffffffffffffda RBX: 000000000059c0a0 RCX: 000000000047959d
> RDX: 0000000000000027 RSI: 0000000020005840 RDI: 0000000000000003
> RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000246 R12: 000000000059c0ac
> R13: 000000000000000b R14: 0000000000437250 R15: 00007f4717def000
>   </TASK>
> Modules linked in:
> Dumping ftrace buffer:
>     (ftrace buffer empty)
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:set_state_bits.isra.0+0x17b/0x1c0 fs/btrfs/extent-io-tree.c:379
> Code: 38 d0 7c 04 84 d2 75 31 44 8b 73 7c e8 be 72 f7 fd 44 89 e0 44
> 09 f0 89 43 7c 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a5 72 f7 fd <0f> 0b
> 4c 89 ef e8 8b 3d 47 fe e9 e6 fe ff ff 4c 89 ef e8 7e 3d 47
> RSP: 0018:ffffc9000675f850 EFLAGS: 00010212
> RAX: 000000000003f702 RBX: ffff88802100cc00 RCX: ffffc90002e49000
> RDX: 0000000000040000 RSI: ffffffff8388e7eb RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
> R10: 00000000fffffff4 R11: 0000000032343854 R12: 0000000000000800
> R13: ffff88802100cc7c R14: 0000000000000fff R15: 0000000000000000
> FS:  00007f4717e0f640(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000505c10 CR3: 0000000018d77000 CR4: 0000000000750ef0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> PKRU: 55555554
>
> RDX: 0000000000040000 RSI: ffffffff8388e7eb RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
> R10: 00000000fffffff4 R11: 0000000032343854 R12: 0000000000000800
> R13: ffff88802100cc7c R14: 0000000000000fff R15: 0000000000000000
> FS:  00007f4717e0f640(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000505c10 CR3: 0000000018d77000 CR4: 0000000000750ef0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> PKRU: 55555554
> Call Trace:
>   <TASK>
>   insert_state_fast fs/btrfs/extent-io-tree.c:437 [inline]
>   __set_extent_bit+0x418/0x15b0 fs/btrfs/extent-io-tree.c:1034
>   set_record_extent_bits+0x53/0x90 fs/btrfs/extent-io-tree.c:1705
>   qgroup_reserve_data+0x233/0xa80 fs/btrfs/qgroup.c:3800
>   btrfs_qgroup_reserve_data+0x2b/0xc0 fs/btrfs/qgroup.c:3843
>   btrfs_check_data_free_space+0x114/0x290 fs/btrfs/delalloc-space.c:154
>   btrfs_buffered_write+0x4ec/0x1330 fs/btrfs/file.c:1250
>   btrfs_do_write_iter+0xb75/0x11c0 fs/btrfs/file.c:1670
>   call_write_iter include/linux/fs.h:1877 [inline]
>   new_sync_write fs/read_write.c:491 [inline]
>   vfs_write+0x989/0xdb0 fs/read_write.c:584
>   ksys_pwrite64 fs/read_write.c:699 [inline]
>   __do_sys_pwrite64 fs/read_write.c:709 [inline]
>   __se_sys_pwrite64 fs/read_write.c:706 [inline]
>   __x64_sys_pwrite64+0x1ef/0x240 fs/read_write.c:706
>   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>   do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>   entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x47959d
> Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 b4 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007f4717e0f068 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
> RAX: ffffffffffffffda RBX: 000000000059c0a0 RCX: 000000000047959d
> RDX: 0000000000000027 RSI: 0000000020005840 RDI: 0000000000000003
> RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000246 R12: 000000000059c0ac
> R13: 000000000000000b R14: 0000000000437250 R15: 00007f4717def000
>   </TASK>
> Modules linked in:
> Dumping ftrace buffer:
>     (ftrace buffer empty)
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:set_state_bits.isra.0+0x17b/0x1c0 fs/btrfs/extent-io-tree.c:379
> Code: 38 d0 7c 04 84 d2 75 31 44 8b 73 7c e8 be 72 f7 fd 44 89 e0 44
> 09 f0 89 43 7c 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a5 72 f7 fd <0f> 0b
> 4c 89 ef e8 8b 3d 47 fe e9 e6 fe ff ff 4c 89 ef e8 7e 3d 47
> RSP: 0018:ffffc9000675f850 EFLAGS: 00010212
> RAX: 000000000003f702 RBX: ffff88802100cc00 RCX: ffffc90002e49000
> RDX: 0000000000040000 RSI: ffffffff8388e7eb RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
> R10: 00000000fffffff4 R11: 0000000032343854 R12: 0000000000000800
> R13: ffff88802100cc7c R14: 0000000000000fff R15: 0000000000000000
> FS:  00007f4717e0f640(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000505c10 CR3: 0000000018d77000 CR4: 0000000000750ef0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> PKRU: 55555554
> Kernel panic - not syncing: Fatal exception
> Dumping ftrace buffer:
>     (ftrace buffer empty)
> Kernel Offset: disabled
> Rebooting in 1 seconds..