From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f78.google.com (mail-ot1-f78.google.com [209.85.210.78]) (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 5CA4B3B05BD for ; Sun, 9 Aug 2026 19:13:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786302821; cv=none; b=BqmFXxAGysXmeiGXTeqvIuxPZ/QzQOC4JCgVz/xysYm+nYi44iZht+A4eEuyN7O9AttrRsBNpXD9nnx8hnPapPxdG5tift/OagSBcMyoXN2P5ADZsR1b2jEJ2QP2zHzbKuG+Ll3yd5UbO5objCdI5j2fDGm1bcWOfbYmOMeTul8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786302821; c=relaxed/simple; bh=2b1WiZTnCcPOFsbbumIvx0wN6TuVbDd/NU+5LTA+Dl4=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=jCneQapUGp+oimxSlUD1JkwRMvw/TPmCzSug+SxW6k4x6SWdys2WX1MEdnLDuSHGrqqc6i/qFv132uYlR0rfQzA293rG8mibQwsFGI9P7j39s95Oy4yeTuRKrzQFJmYeQskjERx2jVb3jwwfkdBTWnKqAufCEwWc6+z1irPQITE= 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=209.85.210.78 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-ot1-f78.google.com with SMTP id 46e09a7af769-7eb64224fd2so2438836a34.0 for ; Sun, 09 Aug 2026 12:13:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786302816; x=1786907616; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=nr9czbpiDY2aYjkJ1zIfJ1Y8AGVvSucR8vX6OAs8zKU=; b=rZswlziTxzqGH69e/YzCW2xxzs6gulooziAYyNNcpJ4vInFDXbdTXaqHExWMsyVut+ rnVCobp0519Fr0mXkbbvvlbgioJOSdYIDiahTKJWmf1nF4WvKfKEpZ4QDjnaGCwohK6u nHDxej6IKgJjGGioddh8WoxzXNNpe6CnRE+cR8RnS3UVmfBTICciJhHf1SerAUXpO8me QAdkF+0CPAKGN+IGoY9AYO3krU4kG//J3Mpbg6dsVTcOhYteqCa61zstFYeldll+bj0h 034ypZ7PZvoX6fuk/4eC+Sqoip3dCGwA2xpFbhBYW5QlTdypyczlgCI+mHkxJm6hUNu6 SR8A== X-Forwarded-Encrypted: i=1; AHgh+RqI2p5UsLNZxY65yKBRNclIpL0nZ+TrI/WB4Cv8SdA8+zZH8PMA9Dl2S4qrjZds3AM9pZhhRPUg0UCnLhg=@vger.kernel.org X-Gm-Message-State: AOJu0Yxu9karcjdrAZFKQvkiD681evij7nH9qH4szEtRKu7AhPdRhmIN BA/dCuWpkzlWW4y7nv0ahD7jlFgodw0xx792AgWiRP/qV9LXES2WhhVXnqMBnlHvFN4iP5zXVlt m+XJyCwuxI80+gNvs32dpLF8QpfgYp+wr7IHrXSwp0nUHxszH+pXY0GDMr0A= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2084:b0:6aa:a1e5:f596 with SMTP id 006d021491bc7-6ae96c1005dmr19512692eaf.3.1786302816187; Sun, 09 Aug 2026 12:13:36 -0700 (PDT) Date: Sun, 09 Aug 2026 12:13:36 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a78d160.01d0871a.3a0d52.0090.GAE@google.com> Subject: [syzbot] [usb?] WARNING: refcount bug in trace_suspend_resume (2) From: syzbot To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 3f008280327b Merge tag 'pinctrl-v7.2-3' of git://git.kerne.. git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master console output: https://syzkaller.appspot.com/x/log.txt?x=16e7efb9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=fa49d7bda29d9792 dashboard link: https://syzkaller.appspot.com/bug?extid=8496ab5e117502750445 compiler: arm-linux-gnueabi-gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: arm syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17013fb9580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1557a132580000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/98a89b9f34e4/non_bootable_disk-3f008280.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ac9e46e45e52/vmlinux-3f008280.xz kernel image: https://storage.googleapis.com/syzbot-assets/491a8a3d010a/zImage-3f008280.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8496ab5e117502750445@syzkaller.appspotmail.com udc dummy_udc.1: failed to start USB Gadget filesystem: -12 gadgetfs gadget.1: probe with driver gadgetfs failed with error -12 UDC core: USB Gadget filesystem: couldn't find an available UDC ------------[ cut here ]------------ WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x134/0x170 lib/refcount.c:28, CPU#0: syz.2.17/4036 refcount_t: underflow; use-after-free. Modules linked in: Kernel panic - not syncing: kernel: panic_on_warn set ... CPU: 0 UID: 0 PID: 4036 Comm: syz.2.17 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express Call trace: [<80201998>] (dump_backtrace) from [<80201a8c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257) r7:82a20f78 r6:00000000 r5:82333190 r4:00000001 [<80201a74>] (show_stack) from [<8021e60c>] (__dump_stack lib/dump_stack.c:94 [inline]) [<80201a74>] (show_stack) from [<8021e60c>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120) [<8021e5b0>] (dump_stack_lvl) from [<8021e638>] (dump_stack+0x18/0x1c lib/dump_stack.c:129) r7:82a20f78 r6:00000000 r5:83e0c980 r4:82c83d40 [<8021e620>] (dump_stack) from [<80202590>] (vpanic+0x114/0x320 kernel/panic.c:651) [<8020247c>] (vpanic) from [<802027d0>] (trace_suspend_resume+0x0/0x100 kernel/panic.c:788) r7:809300ec [<8020279c>] (panic) from [<80250a80>] (check_panic_on_warn kernel/panic.c:525 [inline]) [<8020279c>] (panic) from [<80250a80>] (get_taint+0x0/0x1c kernel/panic.c:520) r3:82a0b144 r2:00000001 r1:82318ef4 r0:82320850 [<80250a08>] (check_panic_on_warn) from [<80250bfc>] (__warn+0x98/0x1a4 kernel/panic.c:1104) [<80250b64>] (__warn) from [<80250ef0>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:1144) r8:00000009 r7:8238cee4 r6:e0259da4 r5:83e0c980 r4:00000000 [<80250d0c>] (warn_slowpath_fmt) from [<809300ec>] (refcount_warn_saturate+0x134/0x170 lib/refcount.c:28) r10:8475ea00 r9:00000000 r8:838acb10 r7:8553bc80 r6:835f77f8 r5:00000000 r4:85c7f600 [<8092ffb8>] (refcount_warn_saturate) from [<81120650>] (__refcount_sub_and_test include/linux/refcount.h:400 [inline]) [<8092ffb8>] (refcount_warn_saturate) from [<81120650>] (__refcount_dec_and_test include/linux/refcount.h:432 [inline]) [<8092ffb8>] (refcount_warn_saturate) from [<81120650>] (refcount_dec_and_test include/linux/refcount.h:450 [inline]) [<8092ffb8>] (refcount_warn_saturate) from [<81120650>] (put_dev+0x4c/0x6c drivers/usb/gadget/legacy/inode.c:165) [<81120604>] (put_dev) from [<81120718>] (dev_release+0x48/0x6c drivers/usb/gadget/legacy/inode.c:1215) [<811206d0>] (dev_release) from [<805a1bcc>] (__fput+0xd8/0x2f4 fs/file_table.c:512) r5:040f801b r4:85a2ef00 [<805a1af4>] (__fput) from [<805a1e7c>] (____fput+0x14/0x18 fs/file_table.c:540) r9:00000000 r8:83e0d214 r7:82c846ac r6:83e0c980 r5:83e0d1e0 r4:00000000 [<805a1e68>] (____fput) from [<8027d7c8>] (task_work_run+0x8c/0xb4 kernel/task_work.c:233) [<8027d73c>] (task_work_run) from [<80257888>] (exit_task_work include/linux/task_work.h:40 [inline]) [<8027d73c>] (task_work_run) from [<80257888>] (do_exit+0x2ac/0xadc kernel/exit.c:1009) r9:00000000 r8:e0259e90 r7:83e0d210 r6:850c5d4c r5:83e0c980 r4:850c5c00 [<802575dc>] (do_exit) from [<8025828c>] (do_group_exit+0x40/0x8c kernel/exit.c:1152) r7:00000004 [<8025824c>] (do_group_exit) from [<80269358>] (get_signal+0xa68/0xa90 kernel/signal.c:3046) r7:00000004 r4:83e0c980 [<802688f0>] (get_signal) from [<8022a630>] (do_signal arch/arm/kernel/signal.c:579 [inline]) [<802688f0>] (get_signal) from [<8022a630>] (do_work_pending+0x124/0x4f0 arch/arm/kernel/signal.c:619) r10:00000004 r9:83e0c980 r8:0000001f r7:00000004 r6:8020029c r5:e0259fb0 r4:83e0c980 [<8022a50c>] (do_work_pending) from [<80200088>] (slow_work_pending+0xc/0x24) Exception stack(0xe0259fb0 to 0xe0259ff8) 9fa0: 0000001f 20000400 0000001f 00000000 9fc0: 00000000 00000000 00356310 00000004 003562d8 00000000 003562d8 003562e4 9fe0: 7ef7e798 7ef7e788 00018fa0 001309d0 60000010 00000003 r10:00000004 r9:83e0c980 r8:8020029c r7:00000004 r6:00356310 r5:00000000 r4:00000000 Rebooting in 86400 seconds.. --- 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 syzkaller@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 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: #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