From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f70.google.com (mail-io1-f70.google.com [209.85.166.70]) (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 053244A11 for ; Thu, 17 Jul 2025 03:55:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752724505; cv=none; b=APiOmaOtBnsNmsAMdmk3lcErfh77/POjX1UcuBLA3zE55G6iB/7Pc2IY7lrxoj0Kj3mhrMnT+vC1oCuLifwO6VO8AOOAoHhM8wHR6oK8/gdqNMY4ttgCJO5YqH1vwmkaaxt5dfKT/OE4mxaSF7Q1h+8ccDRtOJub/k61tM+EnyA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752724505; c=relaxed/simple; bh=uMqR9YeljcNjJOg5Q5GY+Iw977S6CLucGyLgjCrPbIQ=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=AKR67zNAe3kphesADT7iUvkqoGAdrNdA6TLipvoPMjIf0Bp0fdXjJY86Qs2rXuhluHClCD7bwgn3bqA7dJ4B8QQXgXLajsptM93r8DfCqS550/on49XJL1Qt3J1X9fIA7oCtuAYaYlba3XCciV+0Cp6C2hB/uJWCH3QJneT+8i0= 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=209.85.166.70 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-io1-f70.google.com with SMTP id ca18e2360f4ac-875bd5522e9so46023139f.2 for ; Wed, 16 Jul 2025 20:55:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1752724503; x=1753329303; 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=H6vNO+KHbmwMPuw1xVmkccFDZAOgyQcKEsbczf1QR28=; b=nFfOa+PGVZe1X4bGZ2fBBbJ3Ndwz2PBQPP4oOYRnRY/xKli7ioOZnW1ptT0yN7aD4E wTUCXAOl2M1SdM5pWGtAek2W3klpdV/BkF8/8e2H1nR14oCxSGiBulh0zndOkYsWUbqQ VpnwM58Djsuh6A+TnpXhvBZzhilu3E54TCHuvG8u0o271v08RzLyXHwNQI7KGF0QYoN+ K+sKVtgeGFEn/aV3oxFejMZnRQb+M8wK2GI2hZSZpnyIn9VNe1hWn42QxHLF+Eg2n5XQ 2+xllgH5yz+UyDyo89iFhdmyJUTPqK3n6IM3vtJlIlyIcGkm4RjjzbdIkb+BPBfMXv0K 45Lg== X-Forwarded-Encrypted: i=1; AJvYcCX6eskNeXdRlGl792A2EfyUqkAiRygxa77GRRhZcJNGP26PtdefqPlES6xgnyLSPyhRj7G3vexKZE2GQH8=@vger.kernel.org X-Gm-Message-State: AOJu0YzomFLb1M8gfsvYsqz5U0uVYKYIbdgXvGK7/Ttk6dA3Fi2KTY1r NKOfEmZikEbDdB8kp8ZRufc6+FT1hS3TC84ZTppPgiM+X8SG8sLCyadtPhjxwxKwZvkOOTgQ9S4 iRNslEc5C6IohjNf1jjgDhby6q3ocLs+4yev1bQf4TauuG8ctrLWgvsurjl8= X-Google-Smtp-Source: AGHT+IHaKC2B+CBLkmls+II5lLbYTJxioCF5F+T1QSg/VN3D1bjKThTP+5B+vkJU0emoTWM3Ypkocyd67oyEBSpK5YxGDWur5dp0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a6b:6513:0:b0:873:35c8:16f9 with SMTP id ca18e2360f4ac-879c28d0ee3mr499571839f.8.1752724503108; Wed, 16 Jul 2025 20:55:03 -0700 (PDT) Date: Wed, 16 Jul 2025 20:55:03 -0700 In-Reply-To: <20250717014623.2253-1-hdanton@sina.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <68787417.a70a0220.693ce.0037.GAE@google.com> Subject: Re: [syzbot] [mm?] KASAN: slab-use-after-free Read in mas_next_slot (2) From: syzbot To: akpm@linux-foundation.org, hdanton@sina.com, liam.howlett@oracle.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, syzkaller-bugs@googlegroups.com, vbabka@suse.cz Content-Type: text/plain; charset="UTF-8" Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: INFO: task hung in exit_mm INFO: task syz.0.16:6665 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250716-syzkaller-ge8352908bdcd-dirty #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.16 state:D stack:26920 pid:6665 tgid:6665 ppid:6577 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5314 [inline] __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6697 __schedule_loop kernel/sched/core.c:6775 [inline] schedule+0x165/0x360 kernel/sched/core.c:6790 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6847 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:423 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f524bb8e963 RSP: 002b:00007ffc99164708 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: fffffffffffffffc RBX: 00007f524b5ff6c0 RCX: 00007f524bb8e963 RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffc99164860 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 INFO: task syz.1.17:6807 blocked for more than 144 seconds. Not tainted 6.16.0-rc6-next-20250716-syzkaller-ge8352908bdcd-dirty #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.17 state:D stack:26920 pid:6807 tgid:6807 ppid:6787 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5314 [inline] __schedule+0x16fd/0x4cf0 kernel/sched/core.c:6697 __schedule_loop kernel/sched/core.c:6775 [inline] schedule+0x165/0x360 kernel/sched/core.c:6790 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6847 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:423 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efc6b58e963 RSP: 002b:00007ffe5b639e88 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: fffffffffffffffc RBX: 00007efc6afff6c0 RCX: 00007efc6b58e963 RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffe5b639fe0 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/0:3/981: 3 locks held by kworker/u8:9/3028: #0: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 #1: ffff8880b8724008 (per_cpu_ptr(&psi_seq, cpu)){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:937 #2: ffff8880b8725918 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8725918 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 2 locks held by getty/5607: #0: ffff88814df960a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz.0.16/6665: #0: ffff8880242d4260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff8880242d4260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.0.16/6666: 1 lock held by syz.1.17/6807: #0: ffff88807b8c57e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88807b8c57e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.1.17/6808: 1 lock held by syz.2.18/6831: #0: ffff88807e36c260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88807e36c260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.2.18/6832: 1 lock held by syz.3.19/6858: #0: ffff88807b8c2ce0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88807b8c2ce0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 3 locks held by syz.3.19/6859: 1 lock held by syz.4.20/6888: #0: ffff88801a476d60 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88801a476d60 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.4.20/6889: 1 lock held by syz.5.21/6925: #0: ffff88801a472220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88801a472220 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.5.21/6926: 1 lock held by syz.6.22/6955: #0: ffff88807f93b7a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88807f93b7a0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.6.22/6956: 1 lock held by syz.7.24/6990: #0: ffff88807c9ec260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:423 [inline] #0: ffff88807c9ec260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.7.24/6992: 2 locks held by dhcpcd/6995: #0: ffff88805e42b808 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff88805e42b808 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline] #0: ffff88805e42b808 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439 #1: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967 1 lock held by dhcpcd/6996: #0: ffff88805e42ca08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff88805e42ca08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline] #0: ffff88805e42ca08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439 1 lock held by dhcpcd/6997: #0: ffff888078933208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888078933208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline] #0: ffff888078933208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439 2 locks held by dhcpcd/6998: #0: ffff888078930208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888078930208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline] #0: ffff888078930208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439 #1: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:967 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250716-syzkaller-ge8352908bdcd-dirty #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted 6.16.0-rc6-next-20250716-syzkaller-ge8352908bdcd-dirty #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:__this_cpu_preempt_check+0xe/0x20 lib/smp_processor_id.c:64 Code: 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 fe 48 c7 c7 00 65 e3 8b bd fe ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 RSP: 0018:ffffc90000a08bc8 EFLAGS: 00000002 RAX: 0000000000000001 RBX: ffffffff822479bd RCX: da4b2af8b834fd00 RDX: ffff888029254d90 RSI: ffffffff8d994444 RDI: ffffffff8be36500 RBP: ffffc90000a08ed0 R08: 00000000c506ef33 R09: 00000000624b5ae2 R10: 000000000000000e R11: ffffffff81ac3010 R12: 0000000000000000 R13: ffffffff81a7e844 R14: ffff88801cecda00 R15: 0000000000000286 FS: 0000000000000000(0000) GS:ffff888125ce2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a7ec2b0660 CR3: 000000005fa88000 CR4: 00000000003526f0 Call Trace: lockdep_hardirqs_off+0x74/0x110 kernel/locking/lockdep.c:4514 trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:104 kasan_quarantine_put+0x3d/0x220 mm/kasan/quarantine.c:207 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free_after_rcu_debug+0x129/0x2a0 mm/slub.c:4730 rcu_do_batch kernel/rcu/tree.c:2584 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2840 handle_softirqs+0x286/0x870 kernel/softirq.c:579 do_softirq+0xec/0x180 kernel/softirq.c:480 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:833 [inline] nsim_dev_trap_report_work+0x7c7/0xb80 drivers/net/netdevsim/dev.c:864 process_one_work kernel/workqueue.c:3239 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Tested on: commit: e8352908 Add linux-next specific files for 20250716 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1523c58c580000 kernel config: https://syzkaller.appspot.com/x/.config?x=2594af20939db736 dashboard link: https://syzkaller.appspot.com/bug?extid=ebfd0e44b5c11034e1eb compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 patch: https://syzkaller.appspot.com/x/patch.diff?x=10776382580000