[syzbot] [block?] general protection fault in bioset_exit (2)

[syzbot] [block?] general protection fault in bioset_exit (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    69e858e0b8b2 Merge tag 'uml-for-linus-6.14-rc1' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11014b24580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d033b14aeef39158
dashboard link: https://syzkaller.appspot.com/bug?extid=76f13f2acac84df26aae
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-69e858e0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a53b888c1f3f/vmlinux-69e858e0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6b5e17edafc0/bzImage-69e858e0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+76f13f2acac84df26aae@syzkaller.appspotmail.com

bucket 0:19 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:20 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:20 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:21 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:21 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:22 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:22 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:23 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:23 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:24 gen 0 has wrong data_type: got free, should be journal, fixing
bucket 0:24 gen 0 data type journal has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:26 gen 0 has wrong data_type: got free, should be btree, fixing
bucket 0:26 gen 0 data type btree has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:27 gen 0 has wrong data_type: got btree, should be need_discard, fixing
bucket 0:27 gen 0 data type need_discard has wrong dirty_sectors: got 256, should be 0, fixing
bucket 0:29 gen 0 has wrong data_type: got free, should be btree, fixing
bucket 0:29 gen 0 data type btree has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:32 gen 0 has wrong data_type: got sb, should be btree, fixing
bucket 0:34 gen 0 has wrong data_type: got user, should be need_discard, fixing
bucket 0:34 gen 0 data type need_discard has wrong dirty_sectors: got 16, should be 0, fixing
bucket 0:35 gen 0 has wrong data_type: got free, should be btree, fixing
bucket 0:35 gen 0 data type btree has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:38 gen 0 has wrong data_type: got free, should be btree, fixing
bucket 0:38 gen 0 data type btree has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:41 gen 0 has wrong data_type: got free, should be btree, fixing
bucket 0:41 gen 0 data type btree has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:120 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:120 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:121 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:121 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:122 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:122 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:123 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:123 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:124 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:124 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:125 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:125 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:126 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:126 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
bucket 0:127 gen 0 has wrong data_type: got free, should be sb, fixing
bucket 0:127 gen 0 data type sb has wrong dirty_sectors: got 0, should be 256, fixing
 done
bcachefs (loop0): going read-write
bcachefs (loop0): journal_replay...
bcachefs (loop0): bch2_journal_replay(): error erofs_journal_err
bcachefs (loop0): bch2_fs_recovery(): error erofs_journal_err
bcachefs (loop0): bch2_fs_start(): error starting filesystem erofs_journal_err
bcachefs (loop0): shutting down
bcachefs (loop0): shutdown complete
Oops: general protection fault, probably for non-canonical address 0x1000000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:qlist_move_cache+0x6a/0x140 mm/kasan/quarantine.c:302
Code: 00 00 00 00 48 8d 47 08 48 89 44 24 18 48 8d 47 10 48 89 44 24 10 48 8d 46 08 48 89 44 24 08 48 8d 46 10 48 89 04 24 4c 89 eb <4d> 8b 6d 00 48 89 df e8 aa 51 47 ff 48 c1 e8 06 48 83 e0 c0 48 8b
RSP: 0018:ffffc9000d3777b0 EFLAGS: 00010006
RAX: 0000000000000140 RBX: 0001000000000000 RCX: ffffffff9a463b08
RDX: ffffffff9a463b10 RSI: ffff888042616c80 RDI: 00000000000cf2c9
RBP: ffffea0000000000 R08: ffffffff816d68ec R09: fffff52001a6eedc
R10: dffffc0000000000 R11: fffff52001a6eedc R12: ffffffff9a463b00
R13: 0001000000000000 R14: ffffc9000d377808 R15: ffff888055273500
FS:  00007f1cd9cce6c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c19933f0c8 CR3: 0000000040e1a000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kasan_quarantine_remove_cache+0x10b/0x180 mm/kasan/quarantine.c:370
 kmem_cache_destroy+0x6e/0x160 mm/slab_common.c:528
 bio_put_slab block/bio.c:155 [inline]
 bioset_exit+0x54e/0x650 block/bio.c:1662
 bch2_fs_fs_io_direct_exit+0x19/0x30 fs/bcachefs/fs-io-direct.c:676
 __bch2_fs_free fs/bcachefs/super.c:547 [inline]
 bch2_fs_release+0x1a9/0x7b0 fs/bcachefs/super.c:613
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 bch2_fs_get_tree+0xdc4/0x1740 fs/bcachefs/fs.c:2299
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 do_new_mount+0x2be/0xb40 fs/namespace.c:3560
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088
 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: 0033:0x7f1cd8d8e54a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f1cd9ccde68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f1cd9ccdef0 RCX: 00007f1cd8d8e54a
RDX: 0000000020000000 RSI: 0000000020000040 RDI: 00007f1cd9ccdeb0
RBP: 0000000020000000 R08: 00007f1cd9ccdef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000040
R13: 00007f1cd9ccdeb0 R14: 000000000000593f R15: 0000000020000380
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:qlist_move_cache+0x6a/0x140 mm/kasan/quarantine.c:302
Code: 00 00 00 00 48 8d 47 08 48 89 44 24 18 48 8d 47 10 48 89 44 24 10 48 8d 46 08 48 89 44 24 08 48 8d 46 10 48 89 04 24 4c 89 eb <4d> 8b 6d 00 48 89 df e8 aa 51 47 ff 48 c1 e8 06 48 83 e0 c0 48 8b
RSP: 0018:ffffc9000d3777b0 EFLAGS: 00010006
RAX: 0000000000000140 RBX: 0001000000000000 RCX: ffffffff9a463b08
RDX: ffffffff9a463b10 RSI: ffff888042616c80 RDI: 00000000000cf2c9
RBP: ffffea0000000000 R08: ffffffff816d68ec R09: fffff52001a6eedc
R10: dffffc0000000000 R11: fffff52001a6eedc R12: ffffffff9a463b00
R13: 0001000000000000 R14: ffffc9000d377808 R15: ffff888055273500
FS:  00007f1cd9cce6c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c19933f0c8 CR3: 0000000040e1a000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	48 8d 47 08          	lea    0x8(%rdi),%rax
   8:	48 89 44 24 18       	mov    %rax,0x18(%rsp)
   d:	48 8d 47 10          	lea    0x10(%rdi),%rax
  11:	48 89 44 24 10       	mov    %rax,0x10(%rsp)
  16:	48 8d 46 08          	lea    0x8(%rsi),%rax
  1a:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
  1f:	48 8d 46 10          	lea    0x10(%rsi),%rax
  23:	48 89 04 24          	mov    %rax,(%rsp)
  27:	4c 89 eb             	mov    %r13,%rbx
* 2a:	4d 8b 6d 00          	mov    0x0(%r13),%r13 <-- trapping instruction
  2e:	48 89 df             	mov    %rbx,%rdi
  31:	e8 aa 51 47 ff       	call   0xff4751e0
  36:	48 c1 e8 06          	shr    $0x6,%rax
  3a:	48 83 e0 c0          	and    $0xffffffffffffffc0,%rax
  3e:	48                   	rex.W
  3f:	8b                   	.byte 0x8b


---
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If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [block?] general protection fault in bioset_exit (2)

[Jens Axboe]

#syz set subsystems: bcachefs
-- 
Jens Axboe

Re: [syzbot] [bcachefs] general protection fault in bioset_exit (2)

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    224e74511041 Merge tag 'kbuild-fixes-v6.14-2' of git://git..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=169b5bf8580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e55cabe422b4fcaf
dashboard link: https://syzkaller.appspot.com/bug?extid=76f13f2acac84df26aae
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14e8b5a4580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1155a898580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6b4272577622/disk-224e7451.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ec492843be2b/vmlinux-224e7451.xz
kernel image: https://storage.googleapis.com/syzbot-assets/013e7903deef/bzImage-224e7451.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6b2a19ba3037/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+76f13f2acac84df26aae@syzkaller.appspotmail.com

bcachefs (loop4): shutting down
bcachefs (loop4): shutdown complete
BUG: unable to handle page fault for address: 0000000000003906
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0 
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5943 Comm: syz-executor233 Not tainted 6.14.0-rc2-syzkaller-00390-g224e74511041 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:qlist_move_cache+0x6a/0x140 mm/kasan/quarantine.c:302
Code: 00 00 00 00 48 8d 47 08 48 89 44 24 18 48 8d 47 10 48 89 44 24 10 48 8d 46 08 48 89 44 24 08 48 8d 46 10 48 89 04 24 4c 89 eb <4d> 8b 6d 00 48 89 df e8 7a 25 48 ff 48 c1 e8 06 48 83 e0 c0 48 8b
RSP: 0000:ffffc900045bf7b0 EFLAGS: 00010006
RAX: 00000000000002c0 RBX: 0000000000003906 RCX: ffffffff9a680288
RDX: ffffffff9a680290 RSI: ffff888064500258 RDI: 0000000000000000
RBP: ffffea0000000000 R08: ffffffff816eac3c R09: fffff520008b7edc
R10: dffffc0000000000 R11: fffff520008b7edc R12: ffffffff9a680280
R13: 0000000000003906 R14: ffffc900045bf808 R15: ffff88814cdb2500
FS:  00007fe4bd5596c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000003906 CR3: 0000000076ddc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kasan_quarantine_remove_cache+0x10b/0x180 mm/kasan/quarantine.c:370
 kmem_cache_destroy+0x6e/0x160 mm/slab_common.c:528
 bio_put_slab block/bio.c:155 [inline]
 bioset_exit+0x54e/0x650 block/bio.c:1662
 bch2_fs_fs_io_direct_exit+0x19/0x30 fs/bcachefs/fs-io-direct.c:676
 __bch2_fs_free fs/bcachefs/super.c:558 [inline]
 bch2_fs_release+0x1a9/0x7b0 fs/bcachefs/super.c:624
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 bch2_fs_get_tree+0xdee/0x17a0 fs/bcachefs/fs.c:2299
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 do_new_mount+0x2be/0xb40 fs/namespace.c:3560
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088
 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: 0033:0x7fe4bddb482a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 7e 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe4bd558fd8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fe4bd558ff0 RCX: 00007fe4bddb482a
RDX: 00004000000058c0 RSI: 0000400000005900 RDI: 00007fe4bd558ff0
RBP: 0000400000005900 R08: 00007fe4bd559030 R09: 000000000000590c
R10: 0000000000010000 R11: 0000000000000282 R12: 00004000000058c0
R13: 00007fe4bd559030 R14: 0000000000000003 R15: 0000000000010000
 </TASK>
Modules linked in:
CR2: 0000000000003906
---[ end trace 0000000000000000 ]---
RIP: 0010:qlist_move_cache+0x6a/0x140 mm/kasan/quarantine.c:302
Code: 00 00 00 00 48 8d 47 08 48 89 44 24 18 48 8d 47 10 48 89 44 24 10 48 8d 46 08 48 89 44 24 08 48 8d 46 10 48 89 04 24 4c 89 eb <4d> 8b 6d 00 48 89 df e8 7a 25 48 ff 48 c1 e8 06 48 83 e0 c0 48 8b
RSP: 0000:ffffc900045bf7b0 EFLAGS: 00010006
RAX: 00000000000002c0 RBX: 0000000000003906 RCX: ffffffff9a680288
RDX: ffffffff9a680290 RSI: ffff888064500258 RDI: 0000000000000000
RBP: ffffea0000000000 R08: ffffffff816eac3c R09: fffff520008b7edc
R10: dffffc0000000000 R11: fffff520008b7edc R12: ffffffff9a680280
R13: 0000000000003906 R14: ffffc900045bf808 R15: ffff88814cdb2500
FS:  00007fe4bd5596c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000003906 CR3: 0000000076ddc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	48 8d 47 08          	lea    0x8(%rdi),%rax
   8:	48 89 44 24 18       	mov    %rax,0x18(%rsp)
   d:	48 8d 47 10          	lea    0x10(%rdi),%rax
  11:	48 89 44 24 10       	mov    %rax,0x10(%rsp)
  16:	48 8d 46 08          	lea    0x8(%rsi),%rax
  1a:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
  1f:	48 8d 46 10          	lea    0x10(%rsi),%rax
  23:	48 89 04 24          	mov    %rax,(%rsp)
  27:	4c 89 eb             	mov    %r13,%rbx
* 2a:	4d 8b 6d 00          	mov    0x0(%r13),%r13 <-- trapping instruction
  2e:	48 89 df             	mov    %rbx,%rdi
  31:	e8 7a 25 48 ff       	call   0xff4825b0
  36:	48 c1 e8 06          	shr    $0x6,%rax
  3a:	48 83 e0 c0          	and    $0xffffffffffffffc0,%rax
  3e:	48                   	rex.W
  3f:	8b                   	.byte 0x8b


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

Re: [syzbot] [bcachefs] general protection fault in bioset_exit (2)

[syzbot]

syzbot has bisected this issue to:

commit 14152654805256d760315ec24e414363bfa19a06
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date:   Mon Nov 25 05:21:27 2024 +0000

    bcachefs: Bad btree roots are now autofix

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=171a52e4580000
start commit:   224e74511041 Merge tag 'kbuild-fixes-v6.14-2' of git://git..
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=149a52e4580000
console output: https://syzkaller.appspot.com/x/log.txt?x=109a52e4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e55cabe422b4fcaf
dashboard link: https://syzkaller.appspot.com/bug?extid=76f13f2acac84df26aae
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14e8b5a4580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1155a898580000

Reported-by: syzbot+76f13f2acac84df26aae@syzkaller.appspotmail.com
Fixes: 141526548052 ("bcachefs: Bad btree roots are now autofix")

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

Re: [syzbot] [bcachefs] general protection fault in bioset_exit (2)

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 3a04334d6282d08fbdd6201e374db17d31927ba3
Author: Alan Huang <mmpgouride@gmail.com>
Date:   Fri Mar 7 16:58:27 2025 +0000

    bcachefs: Fix b->written overflow

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=11c360cc580000
start commit:   76544811c850 Merge tag 'drm-fixes-2025-02-28' of https://g..
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=8de9cc84d5960254
dashboard link: https://syzkaller.appspot.com/bug?extid=76f13f2acac84df26aae
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=159248b7980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13152a97980000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: bcachefs: Fix b->written overflow

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