[syzbot] [bcachefs?] kernel BUG in bch2_btree_path_peek_slot

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 65ae975e97d5 Merge tag 'net-6.13-rc1' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14794d30580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3891b550f14aea0f
dashboard link: https://syzkaller.appspot.com/bug?extid=3ebaf90b49bd97e920ee
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-65ae975e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/53fd215a7a86/vmlinux-65ae975e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/589c729ff0b2/bzImage-65ae975e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ebaf9...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/bcachefs/btree_iter.c:1816!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 4683 Comm: kworker/u5:1 Not tainted 6.12.0-syzkaller-10681-g65ae975e97d5 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: bcachefs bch2_write_point_do_index_updates
RIP: 0010:bch2_btree_path_peek_slot+0xf50/0xf90 fs/bcachefs/btree_iter.c:1816
Code: f7 ff ff 48 89 34 24 be 08 00 00 00 44 89 44 24 08 e8 c4 fa e3 fd 48 8b 34 24 44 8b 44 24 08 e9 50 f7 ff ff e8 51 12 79 fd 90 <0f> 0b e8 49 12 79 fd 90 0f 0b e8 21 4a b6 07 e8 3c 12 79 fd 90 0f
RSP: 0018:ffffc9000de4c0a0 EFLAGS: 00010293
RAX: ffffffff841cd22f RBX: 0000000000002164 RCX: ffff88801f290000
RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000
RBP: ffffc9000de4c1b0 R08: ffffffff841cc410 R09: 0000000000000000
R10: ffffc9000de4c300 R11: fffff52001bc9862 R12: dffffc0000000000
R13: 1ffff1100adc228d R14: ffff888056e11448 R15: 1ffff1100adc228c
FS: 0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe0e030d38 CR3: 000000004f5d2000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bch2_btree_iter_peek_slot+0xa2f/0x2550 fs/bcachefs/btree_iter.c:2658
__bch2_bkey_get_iter fs/bcachefs/btree_iter.h:575 [inline]
bch2_bkey_get_iter fs/bcachefs/btree_iter.h:589 [inline]
try_alloc_bucket fs/bcachefs/alloc_foreground.c:305 [inline]
bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:525 [inline]
bch2_bucket_alloc_trans+0x1997/0x3a50 fs/bcachefs/alloc_foreground.c:648
bch2_bucket_alloc_set_trans+0x517/0xd30 fs/bcachefs/alloc_foreground.c:808
__open_bucket_add_buckets+0x13d0/0x1ec0 fs/bcachefs/alloc_foreground.c:1057
open_bucket_add_buckets+0x33a/0x410 fs/bcachefs/alloc_foreground.c:1101
bch2_alloc_sectors_start_trans+0xce9/0x2030
__bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:339 [inline]
bch2_btree_reserve_get+0x612/0x1890 fs/bcachefs/btree_update_interior.c:549
bch2_btree_update_start+0xe56/0x14e0 fs/bcachefs/btree_update_interior.c:1247
bch2_btree_split_leaf+0x123/0x840 fs/bcachefs/btree_update_interior.c:1856
bch2_trans_commit_error+0x212/0x1390 fs/bcachefs/btree_trans_commit.c:942
__bch2_trans_commit+0x7ead/0x93c0 fs/bcachefs/btree_trans_commit.c:1140
bch2_trans_commit fs/bcachefs/btree_update.h:184 [inline]
btree_key_cache_flush_pos fs/bcachefs/btree_key_cache.c:432 [inline]
bch2_btree_key_cache_journal_flush+0x97d/0xe70 fs/bcachefs/btree_key_cache.c:512
journal_flush_pins+0x5f7/0xb20 fs/bcachefs/journal_reclaim.c:565
__bch2_journal_reclaim+0x789/0xdc0 fs/bcachefs/journal_reclaim.c:698
__journal_res_get+0x1de3/0x2670 fs/bcachefs/journal.c:581
bch2_journal_res_get_slowpath+0xe6/0x710 fs/bcachefs/journal.c:606
bch2_journal_res_get fs/bcachefs/journal.h:382 [inline]
bch2_trans_journal_res_get fs/bcachefs/btree_trans_commit.c:350 [inline]
bch2_trans_commit_error+0xd91/0x1390 fs/bcachefs/btree_trans_commit.c:962
__bch2_trans_commit+0x7ead/0x93c0 fs/bcachefs/btree_trans_commit.c:1140
bch2_trans_commit fs/bcachefs/btree_update.h:184 [inline]
__bch2_data_update_index_update+0x56bb/0x77f0 fs/bcachefs/data_update.c:368
bch2_data_update_index_update+0x63/0x90 fs/bcachefs/data_update.c:414
__bch2_write_index+0x16d1/0x2140 fs/bcachefs/io_write.c:527
bch2_write_point_do_index_updates+0x32e/0x690 fs/bcachefs/io_write.c:635
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bch2_btree_path_peek_slot+0xf50/0xf90 fs/bcachefs/btree_iter.c:1816
Code: f7 ff ff 48 89 34 24 be 08 00 00 00 44 89 44 24 08 e8 c4 fa e3 fd 48 8b 34 24 44 8b 44 24 08 e9 50 f7 ff ff e8 51 12 79 fd 90 <0f> 0b e8 49 12 79 fd 90 0f 0b e8 21 4a b6 07 e8 3c 12 79 fd 90 0f
RSP: 0018:ffffc9000de4c0a0 EFLAGS: 00010293
RAX: ffffffff841cd22f RBX: 0000000000002164 RCX: ffff88801f290000
RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000
RBP: ffffc9000de4c1b0 R08: ffffffff841cc410 R09: 0000000000000000
R10: ffffc9000de4c300 R11: fffff52001bc9862 R12: dffffc0000000000
R13: 1ffff1100adc228d R14: ffff888056e11448 R15: 1ffff1100adc228c
FS: 0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe0e030d38 CR3: 000000004f5d2000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 7ee983c850b4 Merge tag 'drm-fixes-2025-02-08' of https://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17ef5df8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=147b7d49d83b8036

dashboard link: https://syzkaller.appspot.com/bug?extid=3ebaf90b49bd97e920ee
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=178b8bdf980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/54ead761f64f/disk-7ee983c8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/95e57de2a045/vmlinux-7ee983c8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d24a612a8ac7/bzImage-7ee983c8.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/202515454152/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/d6fc55b76c5c/mount_2.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=119bf0e4580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ebaf9...@syzkaller.appspotmail.com

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

kernel BUG at fs/bcachefs/btree_iter.c:1850!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 2956 Comm: kworker/u8:6 Not tainted 6.14.0-rc1-syzkaller-00181-g7ee983c850b4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: btree_update btree_interior_update_work
RIP: 0010:bch2_btree_path_peek_slot+0xfa2/0xfe0 fs/bcachefs/btree_iter.c:1850
Code: f7 ff ff 48 89 34 24 be 08 00 00 00 44 89 44 24 08 e8 02 60 e4 fd 48 8b 34 24 44 8b 44 24 08 e9 25 f7 ff ff e8 ff 4c 80 fd 90 <0f> 0b e8 f7 4c 80 fd 90 0f 0b e8 8f e7 ae 07 e8 ea 4c 80 fd 90 0f
RSP: 0018:ffffc9000c555800 EFLAGS: 00010293
RAX: ffffffff843f10c1 RBX: 0000000000002164 RCX: ffff8880307cbc00

RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000

RBP: ffffc9000c555910 R08: ffffffff843f0250 R09: 0000000000000000
R10: ffffc9000c555a80 R11: fffff520018aab52 R12: dffffc0000000000
R13: 1ffff1100ff3a08f R14: ffff88807f9d0458 R15: 1ffff1100ff3a08e
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000

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

CR2: 00007f607dda0010 CR3: 000000001eb30000 CR4: 00000000003526f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>

bch2_btree_iter_peek_slot+0xb67/0x27c0 fs/bcachefs/btree_iter.c:2799
__bch2_bkey_get_iter fs/bcachefs/btree_iter.h:573 [inline]
bch2_bkey_get_iter fs/bcachefs/btree_iter.h:587 [inline]
bch2_check_discard_freespace_key+0x292/0xeb0 fs/bcachefs/alloc_background.c:1404
try_alloc_bucket fs/bcachefs/alloc_foreground.c:291 [inline]
bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:442 [inline]
bch2_bucket_alloc_trans+0x1583/0x2ea0 fs/bcachefs/alloc_foreground.c:574
bch2_bucket_alloc_set_trans+0x57c/0xd60 fs/bcachefs/alloc_foreground.c:730
__open_bucket_add_buckets+0x13a2/0x1e10 fs/bcachefs/alloc_foreground.c:973
open_bucket_add_buckets+0x33a/0x410 fs/bcachefs/alloc_foreground.c:1017
bch2_alloc_sectors_start_trans+0xce9/0x2030
__bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:322 [inline]
bch2_btree_reserve_get+0x612/0x1890 fs/bcachefs/btree_update_interior.c:532
bch2_btree_update_start+0xe56/0x14e0 fs/bcachefs/btree_update_interior.c:1230
bch2_btree_split_leaf+0x121/0x880 fs/bcachefs/btree_update_interior.c:1851
bch2_trans_commit_error+0x212/0x1380 fs/bcachefs/btree_trans_commit.c:908
__bch2_trans_commit+0x812b/0x97a0 fs/bcachefs/btree_trans_commit.c:1085
bch2_trans_commit fs/bcachefs/btree_update.h:183 [inline]
btree_update_nodes_written fs/bcachefs/btree_update_interior.c:706 [inline]
btree_interior_update_work+0x1449/0x2a70 fs/bcachefs/btree_update_interior.c:844
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148

ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:bch2_btree_path_peek_slot+0xfa2/0xfe0 fs/bcachefs/btree_iter.c:1850
Code: f7 ff ff 48 89 34 24 be 08 00 00 00 44 89 44 24 08 e8 02 60 e4 fd 48 8b 34 24 44 8b 44 24 08 e9 25 f7 ff ff e8 ff 4c 80 fd 90 <0f> 0b e8 f7 4c 80 fd 90 0f 0b e8 8f e7 ae 07 e8 ea 4c 80 fd 90 0f
RSP: 0018:ffffc9000c555800 EFLAGS: 00010293
RAX: ffffffff843f10c1 RBX: 0000000000002164 RCX: ffff8880307cbc00

RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000

RBP: ffffc9000c555910 R08: ffffffff843f0250 R09: 0000000000000000
R10: ffffc9000c555a80 R11: fffff520018aab52 R12: dffffc0000000000
R13: 1ffff1100ff3a08f R14: ffff88807f9d0458 R15: 1ffff1100ff3a08e
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000

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

CR2: 00007f607e921000 CR3: 0000000031b80000 CR4: 00000000003526f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---

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.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: ed58d103e6da Add linux-next specific files for 20250207
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11c32b18580000
kernel config: https://syzkaller.appspot.com/x/.config?x=244a34ec1429746

dashboard link: https://syzkaller.appspot.com/bug?extid=3ebaf90b49bd97e920ee
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=152811b0580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13443df8580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ce459b7174dd/disk-ed58d103.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/60699733c0c8/vmlinux-ed58d103.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f589bce7c898/bzImage-ed58d103.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/c0e95d2847cc/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ebaf9...@syzkaller.appspotmail.com

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

kernel BUG at fs/bcachefs/btree_iter.c:1850!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 2964 Comm: kworker/u8:8 Not tainted 6.14.0-rc1-next-20250207-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: btree_update btree_interior_update_work
RIP: 0010:bch2_btree_path_peek_slot+0xfa2/0xfe0 fs/bcachefs/btree_iter.c:1850

Code: f7 ff ff 48 89 34 24 be 08 00 00 00 44 89 44 24 08 e8 f2 e5 e3 fd 48 8b 34 24 44 8b 44 24 08 e9 25 f7 ff ff e8 9f 08 7d fd 90 <0f> 0b e8 97 08 7d fd 90 0f 0b e8 bf 88 b7 07 e8 8a 08 7d fd 90 0f
RSP: 0018:ffffc9000bda5800 EFLAGS: 00010293
RAX: ffffffff84428051 RBX: 0000000000002164 RCX: ffff888030423c00

RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000

RBP: ffffc9000bda5910 R08: ffffffff844271e0 R09: 0000000000000000
R10: ffffc9000bda5a80 R11: fffff520017b4b52 R12: dffffc0000000000
R13: 1ffff1100484f0c2 R14: ffff8880242785f0 R15: 1ffff1100484f0c1
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000

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

CR2: 00007f110aa60000 CR3: 0000000077baa000 CR4: 00000000003526f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>

bch2_btree_iter_peek_slot+0xb67/0x27c0 fs/bcachefs/btree_iter.c:2799
__bch2_bkey_get_iter fs/bcachefs/btree_iter.h:573 [inline]
bch2_bkey_get_iter fs/bcachefs/btree_iter.h:587 [inline]
bch2_check_discard_freespace_key+0x292/0xeb0 fs/bcachefs/alloc_background.c:1404

try_alloc_bucket fs/bcachefs/alloc_foreground.c:274 [inline]
bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:425 [inline]
bch2_bucket_alloc_trans+0x1583/0x2ea0 fs/bcachefs/alloc_foreground.c:557
bch2_bucket_alloc_set_trans+0x57c/0xd60 fs/bcachefs/alloc_foreground.c:713
__open_bucket_add_buckets+0x13a2/0x1e10 fs/bcachefs/alloc_foreground.c:956
open_bucket_add_buckets+0x33a/0x410 fs/bcachefs/alloc_foreground.c:1000

bch2_alloc_sectors_start_trans+0xce9/0x2030
__bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:322 [inline]
bch2_btree_reserve_get+0x612/0x1890 fs/bcachefs/btree_update_interior.c:532
bch2_btree_update_start+0xe56/0x14e0 fs/bcachefs/btree_update_interior.c:1230
bch2_btree_split_leaf+0x121/0x880 fs/bcachefs/btree_update_interior.c:1851
bch2_trans_commit_error+0x212/0x1380 fs/bcachefs/btree_trans_commit.c:908

__bch2_trans_commit+0x804d/0x9680 fs/bcachefs/btree_trans_commit.c:1085

bch2_trans_commit fs/bcachefs/btree_update.h:183 [inline]
btree_update_nodes_written fs/bcachefs/btree_update_interior.c:706 [inline]
btree_interior_update_work+0x1449/0x2a70 fs/bcachefs/btree_update_interior.c:844
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
worker_thread+0x870/0xd30 kernel/workqueue.c:3398
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148

ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:bch2_btree_path_peek_slot+0xfa2/0xfe0 fs/bcachefs/btree_iter.c:1850
Code: f7 ff ff 48 89 34 24 be 08 00 00 00 44 89 44 24 08 e8 f2 e5 e3 fd 48 8b 34 24 44 8b 44 24 08 e9 25 f7 ff ff e8 9f 08 7d fd 90 <0f> 0b e8 97 08 7d fd 90 0f 0b e8 bf 88 b7 07 e8 8a 08 7d fd 90 0f
RSP: 0018:ffffc9000bda5800 EFLAGS: 00010293
RAX: ffffffff84428051 RBX: 0000000000002164 RCX: ffff888030423c00

RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000000

RBP: ffffc9000bda5910 R08: ffffffff844271e0 R09: 0000000000000000
R10: ffffc9000bda5a80 R11: fffff520017b4b52 R12: dffffc0000000000
R13: 1ffff1100484f0c2 R14: ffff8880242785f0 R15: 1ffff1100484f0c1
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000

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

CR2: 00007f110a231000 CR3: 000000002f9c4000 CR4: 00000000003526f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---

[syzbot]

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***

Subject:
Author: kent.ov...@linux.dev

#syz fix: bcachefs: fix assert in bch2_btree_path_traverse_cached()