linux-kernel - Re: [syzbot] [jfs?] KMSAN: uninit-value in BT_STACK

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <681a2cdb.050a0220.a19a9.0010.GAE@google.com>
Date: Tue, 06 May 2025 08:38:03 -0700
From: syzbot <syzbot+ba5f49027aace342d24d@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org, richard120310@...il.com, 
	syzkaller-bugs@...glegroups.com
Subject: Re: [syzbot] [jfs?] KMSAN: uninit-value in BT_STACK_DUMP

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