From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f70.google.com (mail-oo1-f70.google.com [209.85.161.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEC4234F27F for ; Fri, 17 Apr 2026 17:48:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776448092; cv=none; b=qvl5x3C+w42oJ/sR1p6dUek821Q/6IxRVLm3cXw7tDB5Xa8LlzDA1RX2yRgjYBbQ8Z/PpyTUhqvqz1qyK1tytucblRvylPEPntos5vGc//Z9sO+T7qkH9hUtK/QqYeNTOC+1wVTYo/yhB53UfGHcRZfxH7mOjLAPad0QrGgF7uI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776448092; c=relaxed/simple; bh=vaszYDl6YsC96k9/VGIlUrPuRbJAljP/1noz5PZGBUg=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=NWUiysCzOnemWqot0Ieruei9rHRLM+1AMVMyc6CARU2wPu6eeX2DlSd5v2i0bWxVbECwYNh4g5EyIPifQan1KCB6fqyK1GzwqpMjIHiJNgrh5Tb9lpdaT0ZlCazBZqzQnzTcP1WfnNrgm6xs6KLprPCS3cErsU57emT9qtpaIXQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f70.google.com with SMTP id 006d021491bc7-679c5ed0942so1608260eaf.1 for ; Fri, 17 Apr 2026 10:48:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776448085; x=1777052885; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=USnEJ7aaRjfdHPJVpjAW+uJV+9LNIBluxf7g11Miz2o=; b=LuomCKfSggpMnyx38TldjYM8/x0xNVSMamU2nYG2URDKT5WU3r97uVlkQBF8YXkwc/ Dnlo2Pd1sVj7flNOZjlgsWLl2QKHRu2zbQuSzSGqkn2KLpfrApbrHRDWQse/FNof1UJl oX0bQ/bjlX7I97B5VW61qypn0qwiEe27G4cAILWz7A+WpkAgbcKpEnQKttZ/yBZwG/mn 0jHKz9hm8FT/59hq0RwKd18O4hO7o2noVY9Iy1iTs3qThIqg8YIRqGQ9yQhwjjKnloxi YUJxC5a0QYjLBwgwYX8O2zExQoEgsC5lVJJLgXpG7QjEpH8W6JPJsTKEocI3ZjCUDRnc niFg== X-Gm-Message-State: AOJu0YxoRqNQ10NRWTWFOvmjFPLnApGXg5HQ5zb9b66Iut35pCuk3zys fN5JBLK1NpdtVkoWpzk8QGpfEBMU7KIoi4RVxKtxpI45wia8oEXhArIOKJsRB01zvxPWE+LOBvG Gkq6VqyqAD4aqlFk4MEgexYrC6IT2y+Xy4W2LtKD8v7+q6MbnMVvmibAMrw0= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4cc8:b0:686:409c:a6f9 with SMTP id 006d021491bc7-69462dee204mr2272753eaf.11.1776448084881; Fri, 17 Apr 2026 10:48:04 -0700 (PDT) Date: Fri, 17 Apr 2026 10:48:04 -0700 In-Reply-To: <177644283705.3787593.12153382858474209734@talencesecurity.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69e27254.a00a0220.1bd0ca.0015.GAE@google.com> Subject: Re: [syzbot] [jfs?] UBSAN: shift-out-of-bounds in extAlloc (2) From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tristmd@gmail.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: KASAN: slab-use-after-free Read in lbmIODone ================================================================== BUG: KASAN: slab-use-after-free in lbmIODone+0x1312/0x16c0 fs/jfs/jfs_logmgr.c:2192 Read of size 4 at addr ffff88803ffe0c08 by task rcuc/0/20 CPU: 0 UID: 0 PID: 20 Comm: rcuc/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 lbmIODone+0x1312/0x16c0 fs/jfs/jfs_logmgr.c:2192 blk_update_request+0x57e/0xe60 block/blk-mq.c:1016 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178 blk_complete_reqs block/blk-mq.c:1253 [inline] blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch kernel/rcu/tree.c:2636 [inline] rcu_core kernel/rcu/tree.c:2869 [inline] rcu_cpu_kthread+0x9e8/0x1470 kernel/rcu/tree.c:2957 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6764: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x3a6/0x690 mm/slub.c:5415 kmalloc_noprof include/linux/slab.h:950 [inline] lbmLogInit fs/jfs/jfs_logmgr.c:1819 [inline] lmLogInit+0x3e5/0x1a00 fs/jfs/jfs_logmgr.c:1267 open_inline_log fs/jfs/jfs_logmgr.c:1173 [inline] lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1067 jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3758 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3834 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4360 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6477: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6561 lbmLogShutdown fs/jfs/jfs_logmgr.c:1862 [inline] lmLogShutdown+0x456/0x850 fs/jfs/jfs_logmgr.c:1681 lmLogClose+0x28a/0x520 fs/jfs/jfs_logmgr.c:1457 jfs_umount+0x2fb/0x3d0 fs/jfs/jfs_umount.c:124 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88803ffe0c00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 8 bytes inside of freed 256-byte region [ffff88803ffe0c00, ffff88803ffe0d00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88803ffe0000 pfn:0x3ffe0 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000240(workingset|head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000240 ffff88813febcb40 ffffea0000e96790 ffffea0000a43190 raw: ffff88803ffe0000 000000080010000f 00000000f5000000 0000000000000000 head: 0080000000000240 ffff88813febcb40 ffffea0000e96790 ffffea0000a43190 head: ffff88803ffe0000 000000080010000f 00000000f5000000 0000000000000000 head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6668, tgid 6667 (syz.0.43), ts 171430926628, free_ts 159679504208 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1860 prep_new_page mm/page_alloc.c:1868 [inline] get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3948 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5228 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x33c/0x3d0 mm/slub.c:7251 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5410 kmalloc_noprof include/linux/slab.h:950 [inline] lbmLogInit fs/jfs/jfs_logmgr.c:1819 [inline] lmLogInit+0x3e5/0x1a00 fs/jfs/jfs_logmgr.c:1267 open_inline_log fs/jfs/jfs_logmgr.c:1173 [inline] lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1067 jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3758 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3834 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4360 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 page last free pid 6150 tgid 6150 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1404 [inline] __free_frozen_pages+0xf48/0x1080 mm/page_alloc.c:2945 __slab_free+0x252/0x2a0 mm/slub.c:5608 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_noprof+0x399/0x7b0 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x246/0x630 security/tomoyo/file.c:728 security_file_ioctl+0xc3/0x2a0 security/security.c:2512 __do_sys_ioctl fs/ioctl.c:591 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88803ffe0b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803ffe0b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803ffe0c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803ffe0c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803ffe0d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Tested on: commit: d730905b Merge tag 'mips_7.1' of git://git.kernel.org/.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master console output: https://syzkaller.appspot.com/x/log.txt?x=14ee24ce580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a4d6a84e42ec71 dashboard link: https://syzkaller.appspot.com/bug?extid=13e8cd4926977f8337b6 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 patch: https://syzkaller.appspot.com/x/patch.diff?x=13624702580000