[syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in __btree_node_pinned

[syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in __btree_node_pinned

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    ad46e8f95e93 Merge tag 'pm-6.12-rc1-2' of git://git.kernel..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13b3d507980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=62086b2fd100a029
dashboard link: https://syzkaller.appspot.com/bug?extid=9f41e4b255897d99d4e9
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=11b69e80580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1567c6a9980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-ad46e8f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/72b7539cbeb1/vmlinux-ad46e8f9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/73c9b9cebaf4/bzImage-ad46e8f9.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/54e2032c8f9d/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9f41e4b255897d99d4e9@syzkaller.appspotmail.com

------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/btree_cache.c:198:18
shift exponent 227 is too large for 64-bit type 'unsigned long long'
CPU: 0 UID: 0 PID: 5109 Comm: read_btree_node Not tainted 6.11.0-syzkaller-11728-gad46e8f95e93 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 __btree_node_pinned+0x80b/0x850 fs/bcachefs/btree_cache.c:198
 __bch2_btree_node_hash_insert+0xcfd/0x13e0 fs/bcachefs/btree_cache.c:270
 bch2_btree_node_hash_insert fs/bcachefs/btree_cache.c:287 [inline]
 bch2_btree_node_fill+0x94e/0x1200 fs/bcachefs/btree_cache.c:932
 bch2_btree_node_get_noiter+0x9d5/0xf70 fs/bcachefs/btree_cache.c:1238
 found_btree_node_is_readable fs/bcachefs/btree_node_scan.c:85 [inline]
 try_read_btree_node fs/bcachefs/btree_node_scan.c:190 [inline]
 read_btree_nodes_worker+0x122c/0x20b0 fs/bcachefs/btree_node_scan.c:239
 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>
---[ end trace ]---
Kernel panic - not syncing: UBSAN: panic_on_warn set ...
CPU: 0 UID: 0 PID: 5109 Comm: read_btree_node Not tainted 6.11.0-syzkaller-11728-gad46e8f95e93 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 panic+0x349/0x880 kernel/panic.c:354
 check_panic_on_warn+0x86/0xb0 kernel/panic.c:243
 ubsan_epilogue lib/ubsan.c:236 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3e7/0x420 lib/ubsan.c:468
 __btree_node_pinned+0x80b/0x850 fs/bcachefs/btree_cache.c:198
 __bch2_btree_node_hash_insert+0xcfd/0x13e0 fs/bcachefs/btree_cache.c:270
 bch2_btree_node_hash_insert fs/bcachefs/btree_cache.c:287 [inline]
 bch2_btree_node_fill+0x94e/0x1200 fs/bcachefs/btree_cache.c:932
 bch2_btree_node_get_noiter+0x9d5/0xf70 fs/bcachefs/btree_cache.c:1238
 found_btree_node_is_readable fs/bcachefs/btree_node_scan.c:85 [inline]
 try_read_btree_node fs/bcachefs/btree_node_scan.c:190 [inline]
 read_btree_nodes_worker+0x122c/0x20b0 fs/bcachefs/btree_node_scan.c:239
 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>
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

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

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.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in __btree_node_pinned

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in bch2_replicas_entry_validate

bcachefs (loop0): starting version 1.7: mi_btree_bitmap opts=errors=continue,metadata_checksum=none,data_checksum=none,compression=lz4,metadata_target=invalid device 255,noshard_inode_numbers,noinodes_use_key_cache,journal_flush_delay=1001,nojournal_transaction_names
============================================
WARNING: possible recursive locking detected
6.12.0-rc1-syzkaller-00296-gac308609567d-dirty #0 Not tainted
--------------------------------------------
syz.0.15/5554 is trying to acquire lock:
ffff88804b880908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_replicas_entry_validate+0x2a/0x80 fs/bcachefs/replicas.c:101

but task is already holding lock:
ffff88804b880908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_read_superblock_clean+0x36/0x520 fs/bcachefs/sb-clean.c:149

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&c->sb_lock);
  lock(&c->sb_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz.0.15/5554:
 #0: ffff88804b880278 (&c->state_lock){+.+.}-{3:3}, at: bch2_fs_start+0x45/0x5b0 fs/bcachefs/super.c:1007
 #1: ffff88804b880908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_read_superblock_clean+0x36/0x520 fs/bcachefs/sb-clean.c:149

stack backtrace:
CPU: 0 UID: 0 PID: 5554 Comm: syz.0.15 Not tainted 6.12.0-rc1-syzkaller-00296-gac308609567d-dirty #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3037
 check_deadlock kernel/locking/lockdep.c:3089 [inline]
 validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 bch2_replicas_entry_validate+0x2a/0x80 fs/bcachefs/replicas.c:101
 journal_entry_data_usage_validate+0x2b6/0x690 fs/bcachefs/journal_io.c:608
 bch2_sb_clean_validate_late fs/bcachefs/sb-clean.c:40 [inline]
 bch2_read_superblock_clean+0x207/0x520 fs/bcachefs/sb-clean.c:168
 bch2_fs_recovery+0x1f4/0x39c0 fs/bcachefs/recovery.c:639
 bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1037
 bch2_fs_get_tree+0xd68/0x1710 fs/bcachefs/fs.c:2071
 vfs_get_tree+0x90/0x2b0 fs/super.c:1800
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
 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: 0033:0x7ffafa97f79a
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:00007ffafb710e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffafb710ef0 RCX: 00007ffafa97f79a
RDX: 0000000020000180 RSI: 0000000020000140 RDI: 00007ffafb710eb0
RBP: 0000000020000180 R08: 00007ffafb710ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000140
R13: 00007ffafb710eb0 R14: 00000000000058f7 R15: 00000000200001c0
 </TASK>


Tested on:

commit:         ac308609 Merge tag 'arm64-fixes' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=153b8d80580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f95955e3f7b5790c
dashboard link: https://syzkaller.appspot.com/bug?extid=9f41e4b255897d99d4e9
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=155c8d27980000

Re: [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in __btree_node_pinned

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in bch2_replicas_entry_validate

bcachefs (loop0): starting version 1.7: mi_btree_bitmap opts=errors=continue,metadata_checksum=none,data_checksum=none,compression=lz4,metadata_target=invalid device 255,noshard_inode_numbers,noinodes_use_key_cache,journal_flush_delay=1001,nojournal_transaction_names
============================================
WARNING: possible recursive locking detected
6.12.0-rc1-syzkaller-00296-gac308609567d-dirty #0 Not tainted
--------------------------------------------
syz.0.15/5646 is trying to acquire lock:
ffff88804a600908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_replicas_entry_validate+0x2a/0x80 fs/bcachefs/replicas.c:101

but task is already holding lock:
ffff88804a600908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_read_superblock_clean+0x36/0x520 fs/bcachefs/sb-clean.c:149

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&c->sb_lock);
  lock(&c->sb_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz.0.15/5646:
 #0: ffff88804a600278 (&c->state_lock){+.+.}-{3:3}, at: bch2_fs_start+0x45/0x5b0 fs/bcachefs/super.c:1007
 #1: ffff88804a600908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_read_superblock_clean+0x36/0x520 fs/bcachefs/sb-clean.c:149

stack backtrace:
CPU: 0 UID: 0 PID: 5646 Comm: syz.0.15 Not tainted 6.12.0-rc1-syzkaller-00296-gac308609567d-dirty #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3037
 check_deadlock kernel/locking/lockdep.c:3089 [inline]
 validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 bch2_replicas_entry_validate+0x2a/0x80 fs/bcachefs/replicas.c:101
 journal_entry_data_usage_validate+0x2b6/0x690 fs/bcachefs/journal_io.c:608
 bch2_sb_clean_validate_late fs/bcachefs/sb-clean.c:40 [inline]
 bch2_read_superblock_clean+0x207/0x520 fs/bcachefs/sb-clean.c:168
 bch2_fs_recovery+0x1f4/0x39c0 fs/bcachefs/recovery.c:639
 bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1037
 bch2_fs_get_tree+0xd68/0x1710 fs/bcachefs/fs.c:2071
 vfs_get_tree+0x90/0x2b0 fs/super.c:1800
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
 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: 0033:0x7f035137f79a
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:00007f0352155e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f0352155ef0 RCX: 00007f035137f79a
RDX: 0000000020000180 RSI: 0000000020000140 RDI: 00007f0352155eb0
RBP: 0000000020000180 R08: 00007f0352155ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000140
R13: 00007f0352155eb0 R14: 00000000000058f7 R15: 00000000200001c0
 </TASK>


Tested on:

commit:         ac308609 Merge tag 'arm64-fixes' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15484d80580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f95955e3f7b5790c
dashboard link: https://syzkaller.appspot.com/bug?extid=9f41e4b255897d99d4e9
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=104c1bd0580000

Re: [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in __btree_node_pinned

[syzbot]

syzbot has bisected this issue to:

commit 7a51608d0125469664e2daf8e060d6d783924c98
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date:   Thu Sep 5 00:49:37 2024 +0000

    bcachefs: Rework btree node pinning

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=115c06c4580000
start commit:   ccb98ccef0e5 Merge tag 'platform-drivers-x86-v6.13-4' of g..
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=135c06c4580000
console output: https://syzkaller.appspot.com/x/log.txt?x=155c06c4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ba7cde9482d6bb6
dashboard link: https://syzkaller.appspot.com/bug?extid=9f41e4b255897d99d4e9
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=118c28b0580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11d45af8580000

Reported-by: syzbot+9f41e4b255897d99d4e9@syzkaller.appspotmail.com
Fixes: 7a51608d0125 ("bcachefs: Rework btree node pinning")

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

Re: [syzbot] [bcachefs?] UBSAN: shift-out-of-bounds in __btree_node_pinned

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+9f41e4b255897d99d4e9@syzkaller.appspotmail.com
Tested-by: syzbot+9f41e4b255897d99d4e9@syzkaller.appspotmail.com

Tested on:

commit:         51a24b7d Merge tag 'trace-tools-v6.17-rc5' of git://gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=165292e2580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=229a4110fb045cc6
dashboard link: https://syzkaller.appspot.com/bug?extid=9f41e4b255897d99d4e9
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.