From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f206.google.com (mail-il1-f206.google.com [209.85.166.206]) (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 874CA274FC2 for ; Wed, 18 Jun 2025 12:56:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750251393; cv=none; b=UPgNV2od07MtDvfcJT4DLlRD7httP7f42vLGJ1YRl4okt+CNuLNknFt6LFtx1sHtzop+wEOHC959SuUmOD0g7e3ELRMD6VDqrfwea/mbY0l0svs3AhDL9aTGDUzla6BZtOoy6PTh9Xs5BL53oPErO4vWEhOdOYAI6LKlDeMF/lg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750251393; c=relaxed/simple; bh=vsZlVMPDHJEYBLzq+vc5tdWK+Sh+xIRbpB7LJVWwQQk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=g+MaL6svuOGnnPeyK12dc+vke2vjeFPSzS63Ho2IsVkMzQ0H/cqDOx+/M4KDF5mSZAdxAfsgsVGQPFuK/sGyU8CjutT10dF7OFBjVkeClF+BPU5rm2mvBZzamQRm1oJrFH++DifILVTI6XCvdBktKMO7vjngyVTNKfiyqZZJP2Y= 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=209.85.166.206 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-f206.google.com with SMTP id e9e14a558f8ab-3ddccc79b55so47758975ab.0 for ; Wed, 18 Jun 2025 05:56:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1750251391; x=1750856191; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=H/0Sg4q8lvuTw5Df2gusQ/ikE58oc87m9xvuN8y1bCw=; b=rIEj1LqZktu9o6osI1ZPYIouLJNEXs8gUcwb8GMLZA+37uzMY1shdG5JWgWbYT/B17 JAQy5r684pFlCRPG9MrM4v9tKhiq7OfIYTigh7pPUVwC7v25CyndG2KeSD8tHSHG9TcK mp+DueNHD5Fm1L8NunA8uz59xlW04njlBmnHtMzKl62OLdfijLb7SpxMX6n8fDD4M/Xc TSAujBorKvuxCw/kzd67FrvqLjS4uUfVIszFEPsq8/igfybvQmyIrLruSZ8MAITTIVAB 5lIvSdJmdMFUoOx0jYbAnjK1gusQC0/TAUa+SCsSCcf+wUG3p4rO8pdva8c/eUkF9eoH pgzg== X-Gm-Message-State: AOJu0YxXHCqVH0ei2aPJgQbxyPSDpmyqnFxs/1Ir/iylG3n+Q2XVaF3+ pezXDSE7t+eDS3Vna1Ln6RZwzRe3K3MPyp2xuWZV0uNij1izPsBEyoqIB+DvkapycO/fGofahNh KBBIaLrfWLipm+4egxnb0HUb87n+97O04qhY1izxcErEloKg8vbTs3LiomHB/cA== X-Google-Smtp-Source: AGHT+IGXQBVuFucsP9xkZepT9fvWxo1RbWlgXKPDz/5etQlp4temXcTIhqGTfm2M/3ffHbeSGlZKLs6Ai6WNXNon3o6mxffuAoSU Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1a44:b0:3dc:7df8:c830 with SMTP id e9e14a558f8ab-3de07c55a19mr199296725ab.7.1750251390730; Wed, 18 Jun 2025 05:56:30 -0700 (PDT) Date: Wed, 18 Jun 2025 05:56:30 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6852b77e.a70a0220.79d0a.0215.GAE@google.com> Subject: [syzbot] [kernel?] WARNING: refcount bug in delayed_put_task_struct From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 4663747812d1 Merge tag 'platform-drivers-x86-v6.16-2' of g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11d5de82580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d6f01a06a8393850 dashboard link: https://syzkaller.appspot.com/bug?extid=fb194529d2cbbf9f1467 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1627d5d4580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/ef27ce1c74bb/disk-46637478.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2962783b1956/vmlinux-46637478.xz kernel image: https://storage.googleapis.com/syzbot-assets/faa841f27097/bzImage-46637478.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+fb194529d2cbbf9f1467@syzkaller.appspotmail.com ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 6673 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Modules linked in: CPU: 1 UID: 0 PID: 6673 Comm: kworker/u8:12 Not tainted 6.16.0-rc2-syzkaller-00045-g4663747812d1 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Code: ff 89 de e8 a8 e3 e2 fc 84 db 0f 85 66 ff ff ff e8 bb e8 e2 fc c6 05 a9 f1 b7 0b 01 90 48 c7 c7 a0 0f 15 8c e8 67 00 a2 fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 98 e8 e2 fc 0f b6 1d 84 f1 b7 0b 31 RSP: 0018:ffffc90000a08dd8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817aa1a8 RDX: ffff88802e90da00 RSI: ffffffff817aa1b5 RDI: 0000000000000001 RBP: ffff88805ae68028 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000008e038 R12: ffff88805ae68000 R13: ffff88805ae68028 R14: ffffc90000a08e90 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff888124861000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8ed0a91f98 CR3: 0000000077b4c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __refcount_sub_and_test include/linux/refcount.h:400 [inline] __refcount_dec_and_test include/linux/refcount.h:432 [inline] refcount_dec_and_test include/linux/refcount.h:450 [inline] put_task_struct include/linux/sched/task.h:134 [inline] delayed_put_task_struct+0x239/0x2e0 kernel/exit.c:230 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0x799/0x14e0 kernel/rcu/tree.c:2832 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:kasan_quarantine_put+0x97/0x240 mm/kasan/quarantine.c:237 Code: 00 00 00 00 00 48 03 5a 10 48 89 5a 10 48 81 fb 00 00 10 00 0f 87 94 00 00 00 4d 85 ed 75 79 9c 58 f6 c4 02 0f 85 6d 01 00 00 <5b> b8 01 00 00 00 5d 41 5c 41 5d 41 5e e9 47 b4 5d 09 e8 82 db a1 RSP: 0018:ffffc9000b4c7ac0 EFLAGS: 00000246 RAX: 0000000000000006 RBX: 000000000009b258 RCX: 0000000000000006 RDX: 0000000000000000 RSI: ffffffff8de13aed RDI: ffffffff8c1563e0 RBP: ffff8880362b4640 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90a83057 R11: 0000000000002c00 R12: ffff88801fea08c0 R13: 0000000000000200 R14: ffffea0000d8ad00 R15: 0000000000000000 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745 kfree_skbmem+0x1a4/0x1f0 net/core/skbuff.c:1110 __kfree_skb net/core/skbuff.c:1167 [inline] consume_skb net/core/skbuff.c:1398 [inline] consume_skb+0xcc/0x100 net/core/skbuff.c:1392 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x8bd/0xcf0 drivers/net/netdevsim/dev.c:851 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 4: 00 48 03 add %cl,0x3(%rax) 7: 5a pop %rdx 8: 10 48 89 adc %cl,-0x77(%rax) b: 5a pop %rdx c: 10 48 81 adc %cl,-0x7f(%rax) f: fb sti 10: 00 00 add %al,(%rax) 12: 10 00 adc %al,(%rax) 14: 0f 87 94 00 00 00 ja 0xae 1a: 4d 85 ed test %r13,%r13 1d: 75 79 jne 0x98 1f: 9c pushf 20: 58 pop %rax 21: f6 c4 02 test $0x2,%ah 24: 0f 85 6d 01 00 00 jne 0x197 * 2a: 5b pop %rbx <-- trapping instruction 2b: b8 01 00 00 00 mov $0x1,%eax 30: 5d pop %rbp 31: 41 5c pop %r12 33: 41 5d pop %r13 35: 41 5e pop %r14 37: e9 47 b4 5d 09 jmp 0x95db483 3c: e8 .byte 0xe8 3d: 82 (bad) 3e: db .byte 0xdb 3f: a1 .byte 0xa1 --- This report is generated by a bot. 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