From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f207.google.com (mail-il1-f207.google.com [209.85.166.207]) (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 4350D2EF65C for ; Tue, 18 Nov 2025 06:49:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763448576; cv=none; b=FLFc9tgE3VgjVpmhd5nSqUXWNSbw2W2ECyPdYhBQNRA0OX0kggKU3UXpXD2KRg80Y5IzmieoY2qakyh4KgBCGJM265ZXgMHuejvVG9mrEJIscEbxBL4vjJ114++ml1W30Kb03BLn9SPl+AnEtVybrbdm/C0AvdJQ7igXJU4+Kr4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763448576; c=relaxed/simple; bh=S6sHFOLObZ9XXLTkGGXS49/PCdRphNoWr9aH32If8wc=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=b4qWGDRkku6h13VshstTwSmJhU7RmY1OPnLjBOzcbZ2w/eiR0GC7hBukqDFgbNhlJlXCho+x0u+Q5RuPyvZwTJcFp+1IzrIidkSfIPPQjXsEwO/s+knWqYaT9cvHUDtaiL+wh8YGblarjtiITBELfLjCNMVWGaDuQ1QZ0HzaJAQ= 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=209.85.166.207 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-il1-f207.google.com with SMTP id e9e14a558f8ab-4330bc0373bso50438855ab.0 for ; Mon, 17 Nov 2025 22:49:34 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1763448573; x=1764053373; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=i9T0bLs7M7iFwor/oOnBTPBa+m5jhYZGw1ZQxdaokqk=; b=O6mSMlKU+Iw/yiCqOrQ1Q21J8zQZeeUPm+iey5kb60IjqkXDaK3E0DLY5hjIYABf7y QlaUUKRb0+pu861l7+JZE/iBealOmXQAGc+tx4xA40kIe88pD11oS80kBhYKXGvu+v3O WBjqGHt0786fmIxzNLnC1ZJDVzFWWSo7YN1G5s1K/LZq1LxF75w43URmHVk8yeNaZ5ht ampHu4okWXKb3NwTdjTRADrY8BxkS8e/1KuUwJuAHhz8pcuOQiRY5jepbbryOgRhAZyH 9+7N04O1akybXXkNeVHIc/71o0olw9vPDbc+2LIT2bh6jCybovMuisGmWqntGP3kTWjP 6TgA== X-Forwarded-Encrypted: i=1; AJvYcCV6yPzCo4iMCNdjvKhlwz8yjf2QF1yFOoh3gnfPxHIo2tjNQAWYYGrwonnEDzRmHkOHWZqh1ZNQI0l4vIM=@vger.kernel.org X-Gm-Message-State: AOJu0YxDK9/v60JbfhQZDG9Jus4s72lhl/r62ZMK3qT1QlMEN3ikFZaq 7PcQydBFZCZ1vW9AiPvMc0AzQLftTa2huhdzSg+9kyT3t8GgZAtaxiqeQXsZdcoiVjhDjZvvNVh 1NwFa/s81xqUFoXnLtxwSXg61SZBkrKz7/GUVcDqBDVFMFrekA/eLHaZbABY= X-Google-Smtp-Source: AGHT+IGGjp/mkLqjB0dQ5EWZ3myyTXgMFlnl7DaD1dFu4Rp+2xMiViBGCm4/fQtiYnTmdsWvQNM73iW8MP5iKP7Rwhe7vhIZt84S Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:3302:b0:433:2072:9d2c with SMTP id e9e14a558f8ab-4348c89e9d5mr216031485ab.10.1763448573391; Mon, 17 Nov 2025 22:49:33 -0800 (PST) Date: Mon, 17 Nov 2025 22:49:33 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <691c16fd.a70a0220.f6df1.0054.GAE@google.com> Subject: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in hci_cmd_work (2) From: syzbot To: johan.hedberg@gmail.com, linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org, luiz.dentz@gmail.com, marcel@holtmann.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 0f2995693867 Add linux-next specific files for 20251114 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=16e42fcd980000 kernel config: https://syzkaller.appspot.com/x/.config?x=873352b3ee3a5f48 dashboard link: https://syzkaller.appspot.com/bug?extid=4d6b203d625d2f57d4ca compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d8d032a78b87/disk-0f299569.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/cf21de5b7c96/vmlinux-0f299569.xz kernel image: https://storage.googleapis.com/syzbot-assets/4472182fc485/bzImage-0f299569.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+4d6b203d625d2f57d4ca@syzkaller.appspotmail.com Bluetooth: hci3: unexpected cc 0x0c03 length: 249 > 1 Bluetooth: hci4: unexpected cc 0x0c03 length: 249 > 1 Bluetooth: hci1: unexpected cc 0x1003 length: 249 > 9 Bluetooth: hci2: unexpected cc 0x0c03 length: 249 > 1 ================================================================== BUG: KASAN: slab-use-after-free in hci_cmd_work+0x5d0/0x7b0 net/bluetooth/hci_core.c:4174 Read of size 2 at addr ffff888061d8f538 by task kworker/u9:5/5835 CPU: 1 UID: 0 PID: 5835 Comm: kworker/u9:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: hci4 hci_cmd_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 hci_cmd_work+0x5d0/0x7b0 net/bluetooth/hci_core.c:4174 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 52: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_node_noprof+0x43c/0x710 mm/slub.c:5310 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:664 alloc_skb include/linux/skbuff.h:1383 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:510 [inline] hci_cmd_sync_alloc+0x3d/0x3b0 net/bluetooth/hci_sync.c:58 hci_cmd_sync_add net/bluetooth/hci_sync.c:99 [inline] __hci_cmd_sync_sk+0x1a7/0xc70 net/bluetooth/hci_sync.c:168 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:263 [inline] __hci_cmd_sync_status net/bluetooth/hci_sync.c:287 [inline] hci_read_local_features_sync net/bluetooth/hci_sync.c:3708 [inline] hci_init_stage_sync net/bluetooth/hci_sync.c:3623 [inline] hci_init1_sync net/bluetooth/hci_sync.c:3755 [inline] hci_init_sync net/bluetooth/hci_sync.c:4874 [inline] hci_dev_init_sync net/bluetooth/hci_sync.c:5066 [inline] hci_dev_open_sync+0x14b2/0x2dc0 net/bluetooth/hci_sync.c:5144 hci_dev_do_open net/bluetooth/hci_core.c:430 [inline] hci_power_on+0x1b4/0x720 net/bluetooth/hci_core.c:959 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Freed by task 5839: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x197/0x640 mm/slub.c:6774 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] vhci_read+0x49a/0x5b0 drivers/bluetooth/hci_vhci.c:593 vfs_read+0x200/0xa30 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888061d8f500 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 56 bytes inside of freed 240-byte region [ffff888061d8f500, ffff888061d8f5f0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x61d8f flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff8881416a0a00 dead000000000122 0000000000000000 raw: 0000000000000000 00000000000c000c 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5835, tgid 5835 (kworker/u9:5), ts 69895228046, free_ts 69894023338 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3920 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5215 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] kmem_cache_alloc_noprof+0x40f/0x700 mm/slub.c:5265 skb_clone+0x212/0x3a0 net/core/skbuff.c:2069 hci_event_packet+0x1a6/0x1260 net/bluetooth/hci_event.c:7667 hci_rx_work+0x45d/0xfc0 net/bluetooth/hci_core.c:4099 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 page last free pid 2 tgid 2 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2948 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline] __kasan_populate_vmalloc+0x1b2/0x1d0 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:579 [inline] alloc_vmap_area+0xdca/0x1500 mm/vmalloc.c:2124 __get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3220 __vmalloc_node_range_noprof+0x365/0x1640 mm/vmalloc.c:3981 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:4081 alloc_thread_stack_node kernel/fork.c:311 [inline] dup_task_struct+0x3d4/0x830 kernel/fork.c:880 copy_process+0x4ea/0x3930 kernel/fork.c:2011 kernel_clone+0x21e/0x850 kernel/fork.c:2609 kernel_thread+0x10d/0x160 kernel/fork.c:2670 create_kthread kernel/kthread.c:486 [inline] kthreadd+0x575/0x770 kernel/kthread.c:844 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Memory state around the buggy address: ffff888061d8f400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888061d8f480: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc >ffff888061d8f500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888061d8f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff888061d8f600: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. 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