[syzbot] [jfs?] KMSAN: uninit-value in BT_STACK_DUMP

[syzbot] [jfs?] KMSAN: uninit-value in BT_STACK_DUMP

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    02ddfb981de8 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=106abf74580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9dc42c34a3f5c357
dashboard link: https://syzkaller.appspot.com/bug?extid=ba5f49027aace342d24d
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=109589b3980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15ba1f74580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5ca57f5a3f77/disk-02ddfb98.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3f23cbc11e68/vmlinux-02ddfb98.xz
kernel image: https://storage.googleapis.com/syzbot-assets/73e63afac354/bzImage-02ddfb98.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6ef4108d05dc/mount_2.gz
  fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=169bb02f980000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ba5f49027aace342d24d@syzkaller.appspotmail.com

bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
=====================================================
BUG: KMSAN: uninit-value in BT_STACK_DUMP+0x5e5/0x600 fs/jfs/jfs_btree.h:136
 BT_STACK_DUMP+0x5e5/0x600 fs/jfs/jfs_btree.h:136
 dtSearch+0x393f/0x3d30 fs/jfs/jfs_dtree.c:774
 jfs_lookup+0x179/0x590 fs/jfs/namei.c:1461
 lookup_one_qstr_excl_raw+0x204/0x5b0 fs/namei.c:1689
 lookup_one_qstr_excl fs/namei.c:1711 [inline]
 do_unlinkat+0x2e3/0xe50 fs/namei.c:4631
 __do_sys_unlink fs/namei.c:4689 [inline]
 __se_sys_unlink fs/namei.c:4687 [inline]
 __x64_sys_unlink+0x71/0xb0 fs/namei.c:4687
 x64_sys_call+0x29de/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable nd created at:
 __filename_parentat+0x4c/0x990 fs/namei.c:2726
 filename_parentat fs/namei.c:2749 [inline]
 do_unlinkat+0xe3/0xe50 fs/namei.c:4618

CPU: 1 UID: 0 PID: 5791 Comm: syz-executor444 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
=====================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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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:
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(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] [jfs?] KMSAN: uninit-value in BT_STACK_DUMP

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in dtSearch

loop0: detected capacity change from 0 to 32768
=====================================================
BUG: KMSAN: uninit-value in UniStrncmp_le fs/jfs/jfs_unicode.h:55 [inline]
BUG: KMSAN: uninit-value in dtCompare fs/jfs/jfs_dtree.c:3340 [inline]
BUG: KMSAN: uninit-value in dtSearch+0x1261/0x3d30 fs/jfs/jfs_dtree.c:650
 UniStrncmp_le fs/jfs/jfs_unicode.h:55 [inline]
 dtCompare fs/jfs/jfs_dtree.c:3340 [inline]
 dtSearch+0x1261/0x3d30 fs/jfs/jfs_dtree.c:650
 jfs_lookup+0x18b/0x5a0 fs/jfs/namei.c:1461
 lookup_one_qstr_excl_raw+0x204/0x5b0 fs/namei.c:1689
 lookup_one_qstr_excl fs/namei.c:1711 [inline]
 do_unlinkat+0x2e3/0xe50 fs/namei.c:4631
 __do_sys_unlink fs/namei.c:4689 [inline]
 __se_sys_unlink fs/namei.c:4687 [inline]
 __x64_sys_unlink+0x71/0xb0 fs/namei.c:4687
 x64_sys_call+0x29de/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __alloc_frozen_pages_noprof+0x689/0xf00 mm/page_alloc.c:4993
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2301
 alloc_frozen_pages_noprof+0xf7/0x200 mm/mempolicy.c:2372
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab+0x24d/0x1210 mm/slub.c:2632
 new_slab mm/slub.c:2686 [inline]
 ___slab_alloc+0xfec/0x3480 mm/slub.c:3872
 __slab_alloc mm/slub.c:3962 [inline]
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 kmem_cache_alloc_lru_noprof+0x922/0xed0 mm/slub.c:4229
 jfs_alloc_inode+0x60/0xf0 fs/jfs/super.c:105
 alloc_inode+0x87/0x4a0 fs/inode.c:346
 new_inode+0x39/0x460 fs/inode.c:1145
 diReadSpecial+0x62/0xb00 fs/jfs/jfs_imap.c:426
 jfs_mount+0x760/0x1310 fs/jfs/jfs_mount.c:138
 jfs_fill_super+0x8fa/0x1900 fs/jfs/super.c:523
 get_tree_bdev_flags+0x6e3/0x920 fs/super.c:1636
 get_tree_bdev+0x38/0x50 fs/super.c:1659
 jfs_get_tree+0x35/0x40 fs/jfs/super.c:635
 vfs_get_tree+0xb0/0x5c0 fs/super.c:1759
 do_new_mount+0x73c/0x1620 fs/namespace.c:3881
 path_mount+0x6db/0x1e90 fs/namespace.c:4208
 do_mount fs/namespace.c:4221 [inline]
 __do_sys_mount fs/namespace.c:4432 [inline]
 __se_sys_mount+0x6eb/0x7d0 fs/namespace.c:4409
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4409
 x64_sys_call+0xfa7/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 7043 Comm: syz.0.33 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8-dirty #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
=====================================================


Tested on:

commit:         02ddfb98 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1439c8f4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9dc42c34a3f5c357
dashboard link: https://syzkaller.appspot.com/bug?extid=ba5f49027aace342d24d
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
patch:          https://syzkaller.appspot.com/x/patch.diff?x=100ae8f4580000

Re: [syzbot] [jfs?] KMSAN: uninit-value in BT_STACK_DUMP

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: use-after-free in dtSearch

loop0: detected capacity change from 0 to 32768
=====================================================
BUG: KMSAN: use-after-free in UniStrncmp_le fs/jfs/jfs_unicode.h:55 [inline]
BUG: KMSAN: use-after-free in dtCompare fs/jfs/jfs_dtree.c:3340 [inline]
BUG: KMSAN: use-after-free in dtSearch+0x1261/0x3d30 fs/jfs/jfs_dtree.c:650
 UniStrncmp_le fs/jfs/jfs_unicode.h:55 [inline]
 dtCompare fs/jfs/jfs_dtree.c:3340 [inline]
 dtSearch+0x1261/0x3d30 fs/jfs/jfs_dtree.c:650
 jfs_lookup+0x18b/0x5a0 fs/jfs/namei.c:1461
 lookup_one_qstr_excl_raw+0x204/0x5b0 fs/namei.c:1689
 lookup_one_qstr_excl fs/namei.c:1711 [inline]
 do_unlinkat+0x2e3/0xe50 fs/namei.c:4631
 __do_sys_unlink fs/namei.c:4689 [inline]
 __se_sys_unlink fs/namei.c:4687 [inline]
 __x64_sys_unlink+0x71/0xb0 fs/namei.c:4687
 x64_sys_call+0x29de/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_free_hook mm/slub.c:2324 [inline]
 slab_free mm/slub.c:4656 [inline]
 kmem_cache_free+0x286/0xf00 mm/slub.c:4758
 __d_free+0x43/0x60 fs/dcache.c:336
 rcu_do_batch kernel/rcu/tree.c:2568 [inline]
 rcu_core+0xa5a/0x21e0 kernel/rcu/tree.c:2824
 rcu_core_si+0x12/0x20 kernel/rcu/tree.c:2841
 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x66/0x180 kernel/softirq.c:680
 irq_exit_rcu+0x12/0x20 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x84/0x90 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702

CPU: 0 UID: 0 PID: 6979 Comm: syz.0.35 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8-dirty #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
=====================================================


Tested on:

commit:         02ddfb98 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=134ee8f4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9dc42c34a3f5c357
dashboard link: https://syzkaller.appspot.com/bug?extid=ba5f49027aace342d24d
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10efba70580000

Re: [syzbot] [jfs?] KMSAN: uninit-value in BT_STACK_DUMP

[syzbot]

Hello,

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

Reported-by: syzbot+ba5f49027aace342d24d@syzkaller.appspotmail.com
Tested-by: syzbot+ba5f49027aace342d24d@syzkaller.appspotmail.com

Tested on:

commit:         cec1e6e5 Merge tag 'sched_ext-for-6.17-rc7-fixes' of g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17370f12580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1b093ccee5a9e08c
dashboard link: https://syzkaller.appspot.com/bug?extid=ba5f49027aace342d24d
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=128f627c580000

Note: testing is done by a robot and is best-effort only.