[syzbot] [bcachefs?] KMSAN: uninit-value in bch2_bkey_ptrs_validate

10 views
Skip to first unread message

syzbot

unread,
Dec 1, 2024, 3:34:31 AM12/1/24
to kent.ov...@linux.dev, linux-b...@vger.kernel.org, linux-...@vger.kernel.org, syzkall...@googlegroups.com
Hello,

syzbot found the following issue on:

HEAD commit: 445d9f05fa14 Merge tag 'nfsd-6.13' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=150f83c0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c5486b9d7cc64830
dashboard link: https://syzkaller.appspot.com/bug?extid=5d8a06a9e86672d9f71f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7024ceac9339/disk-445d9f05.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ebf50afbcd15/vmlinux-445d9f05.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9e60e080ed9e/bzImage-445d9f05.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5d8a06...@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in __extent_entry_type fs/bcachefs/extents.h:54 [inline]
BUG: KMSAN: uninit-value in bch2_bkey_ptrs_validate+0x589/0x2df0 fs/bcachefs/extents.c:1239
__extent_entry_type fs/bcachefs/extents.h:54 [inline]
bch2_bkey_ptrs_validate+0x589/0x2df0 fs/bcachefs/extents.c:1239
bch2_bkey_val_validate+0x2b5/0x440 fs/bcachefs/bkey_methods.c:143
bset_key_validate fs/bcachefs/btree_io.c:841 [inline]
validate_bset_keys+0x1531/0x2080 fs/bcachefs/btree_io.c:910
validate_bset_for_write+0x142/0x290 fs/bcachefs/btree_io.c:1942
__bch2_btree_node_write+0x53df/0x6830 fs/bcachefs/btree_io.c:2152
bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
bch2_btree_node_rewrite+0x1442/0x1930 fs/bcachefs/btree_update_interior.c:2179
async_btree_node_rewrite_trans fs/bcachefs/btree_update_interior.c:2236 [inline]
async_btree_node_rewrite_work+0x485/0x1710 fs/bcachefs/btree_update_interior.c:2249
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310
worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391
kthread+0x3e2/0x540 kernel/kthread.c:389
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
memcpy_u64s_small fs/bcachefs/util.h:393 [inline]
bkey_p_copy fs/bcachefs/bkey.h:47 [inline]
bch2_sort_keys_keep_unwritten_whiteouts+0x12d5/0x19d0 fs/bcachefs/bkey_sort.c:187
__bch2_btree_node_write+0x3ae8/0x6830 fs/bcachefs/btree_io.c:2095
bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
bch2_btree_node_rewrite+0x1442/0x1930 fs/bcachefs/btree_update_interior.c:2179
async_btree_node_rewrite_trans fs/bcachefs/btree_update_interior.c:2236 [inline]
async_btree_node_rewrite_work+0x485/0x1710 fs/bcachefs/btree_update_interior.c:2249
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310
worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391
kthread+0x3e2/0x540 kernel/kthread.c:389
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
___kmalloc_large_node+0x22c/0x370 mm/slub.c:4238
__kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4255
__do_kmalloc_node mm/slub.c:4271 [inline]
__kmalloc_node_noprof+0xc96/0x1250 mm/slub.c:4289
__kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:650
btree_node_data_alloc fs/bcachefs/btree_cache.c:153 [inline]
__bch2_btree_node_mem_alloc+0x2be/0xa80 fs/bcachefs/btree_cache.c:198
bch2_fs_btree_cache_init+0x4e4/0xb50 fs/bcachefs/btree_cache.c:653
bch2_fs_alloc fs/bcachefs/super.c:917 [inline]
bch2_fs_open+0x4d3a/0x5b40 fs/bcachefs/super.c:2065
bch2_fs_get_tree+0x983/0x22d0 fs/bcachefs/fs.c:2157
vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
do_new_mount+0x71f/0x15e0 fs/namespace.c:3507
path_mount+0x742/0x1f10 fs/namespace.c:3834
do_mount fs/namespace.c:3847 [inline]
__do_sys_mount fs/namespace.c:4057 [inline]
__se_sys_mount+0x722/0x810 fs/namespace.c:4034
__ia32_sys_mount+0xe3/0x150 fs/namespace.c:4034
ia32_sys_call+0x260e/0x4180 arch/x86/include/generated/asm/syscalls_32.h:22
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 3613 Comm: kworker/u8:11 Tainted: G W 6.12.0-syzkaller-09734-g445d9f05fa14 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: btree_node_rewrite async_btree_node_rewrite_work
=====================================================


---
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 syzk...@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 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

syzbot

unread,
Dec 24, 2024, 11:11:27 AM12/24/24
to kent.ov...@linux.dev, linux-b...@vger.kernel.org, linux-...@vger.kernel.org, syzkall...@googlegroups.com
syzbot has found a reproducer for the following issue on:

HEAD commit: f07044dd0df0 Merge tag 'nfsd-6.13-1' of git://git.kernel.o..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15997fe8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f9048090d7bb0d06
dashboard link: https://syzkaller.appspot.com/bug?extid=5d8a06a9e86672d9f71f
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=13997fe8580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1168c2f8580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/079ebaf3a565/disk-f07044dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/489a8d4db9f1/vmlinux-f07044dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a04386952d17/bzImage-f07044dd.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/449cac567e3a/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5d8a06...@syzkaller.appspotmail.com

bcachefs (loop0): snapshots_read... done
bcachefs (loop0): check_allocations... done
bcachefs (loop0): going read-write
bcachefs (loop0): scanning for old btree nodes: min_version 0.24: unwritten_extents
=====================================================
BUG: KMSAN: uninit-value in __extent_entry_type fs/bcachefs/extents.h:54 [inline]
BUG: KMSAN: uninit-value in bch2_bkey_ptrs_validate+0x589/0x2df0 fs/bcachefs/extents.c:1239
__extent_entry_type fs/bcachefs/extents.h:54 [inline]
bch2_bkey_ptrs_validate+0x589/0x2df0 fs/bcachefs/extents.c:1239
bch2_bkey_val_validate+0x2b5/0x440 fs/bcachefs/bkey_methods.c:143
bset_key_validate fs/bcachefs/btree_io.c:841 [inline]
validate_bset_keys+0x1531/0x2080 fs/bcachefs/btree_io.c:910
validate_bset_for_write+0x142/0x290 fs/bcachefs/btree_io.c:1942
__bch2_btree_node_write+0x53df/0x6830 fs/bcachefs/btree_io.c:2152
bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
bch2_btree_node_rewrite+0x1442/0x1930 fs/bcachefs/btree_update_interior.c:2179
bch2_move_btree+0xc32/0x1400 fs/bcachefs/move.c:865
bch2_scan_old_btree_nodes+0x15f/0x580 fs/bcachefs/move.c:995
bch2_fs_recovery+0x58b8/0x5b00 fs/bcachefs/recovery.c:974
bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1037
bch2_fs_get_tree+0x13ea/0x22d0 fs/bcachefs/fs.c:2170
vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
do_new_mount+0x71f/0x15e0 fs/namespace.c:3507
path_mount+0x742/0x1f10 fs/namespace.c:3834
do_mount fs/namespace.c:3847 [inline]
__do_sys_mount fs/namespace.c:4057 [inline]
__se_sys_mount+0x722/0x810 fs/namespace.c:4034
__x64_sys_mount+0xe4/0x150 fs/namespace.c:4034
x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
memcpy_u64s_small fs/bcachefs/util.h:393 [inline]
bkey_p_copy fs/bcachefs/bkey.h:47 [inline]
bch2_sort_keys_keep_unwritten_whiteouts+0x12d5/0x19d0 fs/bcachefs/bkey_sort.c:187
__bch2_btree_node_write+0x3ae8/0x6830 fs/bcachefs/btree_io.c:2095
bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
bch2_btree_node_rewrite+0x1442/0x1930 fs/bcachefs/btree_update_interior.c:2179
bch2_move_btree+0xc32/0x1400 fs/bcachefs/move.c:865
bch2_scan_old_btree_nodes+0x15f/0x580 fs/bcachefs/move.c:995
bch2_fs_recovery+0x58b8/0x5b00 fs/bcachefs/recovery.c:974
bch2_fs_start+0x7b2/0xbd0 fs/bcachefs/super.c:1037
bch2_fs_get_tree+0x13ea/0x22d0 fs/bcachefs/fs.c:2170
vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
do_new_mount+0x71f/0x15e0 fs/namespace.c:3507
path_mount+0x742/0x1f10 fs/namespace.c:3834
do_mount fs/namespace.c:3847 [inline]
__do_sys_mount fs/namespace.c:4057 [inline]
__se_sys_mount+0x722/0x810 fs/namespace.c:4034
__x64_sys_mount+0xe4/0x150 fs/namespace.c:4034
x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
___kmalloc_large_node+0x22c/0x370 mm/slub.c:4253
__kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4270
__do_kmalloc_node mm/slub.c:4286 [inline]
__kmalloc_node_noprof+0xc96/0x1250 mm/slub.c:4304
__kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:650
btree_node_data_alloc fs/bcachefs/btree_cache.c:153 [inline]
__bch2_btree_node_mem_alloc+0x2be/0xa80 fs/bcachefs/btree_cache.c:198
bch2_fs_btree_cache_init+0x4e4/0xb50 fs/bcachefs/btree_cache.c:653
bch2_fs_alloc fs/bcachefs/super.c:917 [inline]
bch2_fs_open+0x4d3a/0x5b40 fs/bcachefs/super.c:2065
bch2_fs_get_tree+0x983/0x22d0 fs/bcachefs/fs.c:2157
vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
do_new_mount+0x71f/0x15e0 fs/namespace.c:3507
path_mount+0x742/0x1f10 fs/namespace.c:3834
do_mount fs/namespace.c:3847 [inline]
__do_sys_mount fs/namespace.c:4057 [inline]
__se_sys_mount+0x722/0x810 fs/namespace.c:4034
__x64_sys_mount+0xe4/0x150 fs/namespace.c:4034
x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 5789 Comm: syz-executor916 Not tainted 6.13.0-rc4-syzkaller-00004-gf07044dd0df0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
=====================================================


---
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

unread,
Apr 1, 2025, 12:02:15 AM4/1/25
to linux-...@vger.kernel.org, syzkall...@googlegroups.com
For archival purposes, forwarding an incoming command email to
linux-...@vger.kernel.org, syzkall...@googlegroups.com.

***

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

#syz fix bcachefs: Disable asm memcpys when kmsan enabled
Reply all
Reply to author
Forward
0 new messages