From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f80.google.com (mail-oo1-f80.google.com [209.85.161.80]) (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 D951630E0F4 for ; Wed, 21 Jan 2026 08:28:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768984105; cv=none; b=g/b34WjtRZBhmK1EggUxrATOKx9CIoFQcFAQ4kWjkkq4X1UbfzAm+TY8urgDh1uRtUM5fAi2N1BOw69hXh1lRWvDUNkzZ8fUNssb/Ft+ooouBlsTr5xw8K/J0Dr5zt0VbZTL/BeroPn+FrNWTgA/qc38yeZHd9EK1c7vO7XLBxY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768984105; c=relaxed/simple; bh=rfRaJi4Tx7sKeA43SsqDEfWYiZRK/YUm+TAxsizoK9c=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=gcj0gLO1JHXmBrpPa4/X9FW8kd6toUOg9sFn4E+FvNGuSx9Dpren9Cq9IkxhZY3HBatCiSvOPrjdTZ3KrYVWtek1KQbibPCzIjekGrSeKzFaYp9i/uvrdGINekStroaindyQ/yRx7BQiE4SCVGvJ5BdIpZNdTnTk79+miVKxgQU= 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=209.85.161.80 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-f80.google.com with SMTP id 006d021491bc7-661125c8491so2837444eaf.3 for ; Wed, 21 Jan 2026 00:28:23 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768984103; x=1769588903; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=VxfWrgxPshYLoeiTcgY5TyfwM7o/XTnpVYAYtYI9tw8=; b=qnNFjZnfxaHL8aOFebCmHkojyQeA9+tBmiGtJOspn+9Y1NHdOkbggKzK0JSi4StcSW 7NyCmONirxMPCAsf6Ger7a041pB8sFrp6KCtKJ47z8VSzwzWHKPoT1dtEH13elfCHYT3 BECpXsxesha+s92nzcQxmfDQ2GabgHe5C8Pafq7oqqviHHhvCBPEtU6EjxsaxPMb0eNR qTQ7hFNansx37Md5j/+fYY742k0Pf0rjRy8EWKClH9XGYypNbdkwzPL0sUFqisda5bF5 O29ny6QfC13jYImR2CjbuRzMlW1gDhPV6EhAufDSMn6U+FlF8mjnuJ+kcpRZcwj18Qxr l3KQ== X-Gm-Message-State: AOJu0YybPcht1AxwzYO8GDNNUvpdpLLCy5dw0qK0oIFwZgwaHZo30EPy jyy7Lgxg9A8ETetyc7lXN3rAI5rBCcrQUXYTHyc//vyUFbJ/LRSKU+m3neN9n2FJI+hyAPalpvb s9ftjzTv7kvPDE3rAf8b8E9c5ewMdTvqZe3owW+dq9EW32myDQQYwOtg5ODYC0w== Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:c81:b0:659:9a49:8f04 with SMTP id 006d021491bc7-662affaeebbmr1747663eaf.21.1768984102808; Wed, 21 Jan 2026 00:28:22 -0800 (PST) Date: Wed, 21 Jan 2026 00:28:22 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69708e26.050a0220.706b.000e.GAE@google.com> Subject: [syzbot] [fs?] KASAN: slab-use-after-free Read in proc_invalidate_siblings_dcache (2) From: syzbot To: linux-fsdevel@vger.kernel.org, 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: 8f0b4cce4481 Linux 6.19-rc1 git tree: git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next console output: https://syzkaller.appspot.com/x/log.txt?x=1251239a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=88cadb2aebdef7ea dashboard link: https://syzkaller.appspot.com/bug?extid=e8b3520b53e78e90034e compiler: riscv64-linux-gnu-gcc (Debian 12.2.0-13) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: riscv64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/a741b348759c/non_bootable_disk-8f0b4cce.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/4c3ed9ab2bac/vmlinux-8f0b4cce.xz kernel image: https://storage.googleapis.com/syzbot-assets/e55c5b55f4c6/Image-8f0b4cce.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e8b3520b53e78e90034e@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in proc_invalidate_siblings_dcache+0x6ae/0x6bc fs/proc/inode.c:114 Read of size 8 at addr ffffaf801aba9a18 by task sshd/3175 CPU: 0 UID: 0 PID: 3175 Comm: sshd Not tainted syzkaller #0 PREEMPT Hardware name: riscv-virtio,qemu (DT) Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:149 [] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:155 [] __dump_stack lib/dump_stack.c:94 [inline] [] dump_stack_lvl+0x12a/0x1a2 lib/dump_stack.c:120 [] print_address_description mm/kasan/report.c:378 [inline] [] print_report+0x28c/0x59e mm/kasan/report.c:482 [] kasan_report+0xf0/0x218 mm/kasan/report.c:595 [] __asan_report_load8_noabort+0x12/0x1a mm/kasan/report_generic.c:381 [] proc_invalidate_siblings_dcache+0x6ae/0x6bc fs/proc/inode.c:114 [] proc_flush_pid+0x20/0x2a fs/proc/base.c:3478 [] release_task+0xc26/0x1908 kernel/exit.c:291 [] wait_task_zombie kernel/exit.c:1274 [inline] [] wait_consider_task+0x17c4/0x3922 kernel/exit.c:1501 [] do_wait_thread kernel/exit.c:1564 [inline] [] __do_wait+0x1b2/0x7ba kernel/exit.c:1682 [] do_wait+0x218/0x6d0 kernel/exit.c:1716 [] kernel_wait4+0x188/0x5b6 kernel/exit.c:1875 [] __do_sys_wait4+0x156/0x162 kernel/exit.c:1903 [] __se_sys_wait4 kernel/exit.c:1899 [inline] [] __riscv_sys_wait4+0x8a/0xd6 kernel/exit.c:1899 [] syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112 [] do_trap_ecall_u+0x3d8/0x56c arch/riscv/kernel/traps.c:343 [] handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:198 Allocated by task 3175: stack_trace_save+0xa0/0xd2 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x6a mm/kasan/common.c:56 kasan_save_track+0x16/0x28 mm/kasan/common.c:77 kasan_save_alloc_info+0x30/0x3e mm/kasan/generic.c:570 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x7c/0x82 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x1f6/0x80e mm/slub.c:5270 alloc_pid+0xd8/0x12fe kernel/pid.c:183 copy_process+0x408e/0x748e kernel/fork.c:2237 kernel_clone+0x128/0xdb0 kernel/fork.c:2651 __do_sys_clone+0xfe/0x13e kernel/fork.c:2792 __se_sys_clone kernel/fork.c:2760 [inline] __riscv_sys_clone+0xa0/0x10e kernel/fork.c:2760 syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x3d8/0x56c arch/riscv/kernel/traps.c:343 handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:198 Freed by task 3190: stack_trace_save+0xa0/0xd2 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x6a mm/kasan/common.c:56 kasan_save_track+0x16/0x28 mm/kasan/common.c:77 kasan_save_free_info+0x40/0x5a mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5e/0x7e 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:6668 [inline] kmem_cache_free+0x300/0x882 mm/slub.c:6779 put_pid.part.0+0x104/0x144 kernel/pid.c:100 put_pid+0x24/0x36 kernel/pid.c:94 proc_free_inode+0x4a/0xbc fs/proc/inode.c:76 i_callback+0x42/0x8e fs/inode.c:325 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xa36/0x1ed2 kernel/rcu/tree.c:2857 rcu_core_si+0xc/0x14 kernel/rcu/tree.c:2874 handle_softirqs+0x4b6/0x1336 kernel/softirq.c:622 __do_softirq+0x12/0x1a kernel/softirq.c:656 Last potentially related work creation: stack_trace_save+0xa0/0xd2 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x6a mm/kasan/common.c:56 kasan_record_aux_stack+0x114/0x160 mm/kasan/generic.c:556 __call_rcu_common.constprop.0+0x9e/0x9de kernel/rcu/tree.c:3119 call_rcu+0xc/0x14 kernel/rcu/tree.c:3239 free_pid+0x278/0x354 kernel/pid.c:147 free_pids+0x4c/0x8a kernel/pid.c:159 release_task+0xc3e/0x1908 kernel/exit.c:295 wait_task_zombie kernel/exit.c:1274 [inline] wait_consider_task+0x17c4/0x3922 kernel/exit.c:1501 do_wait_thread kernel/exit.c:1564 [inline] __do_wait+0x1b2/0x7ba kernel/exit.c:1682 do_wait+0x218/0x6d0 kernel/exit.c:1716 kernel_wait4+0x188/0x5b6 kernel/exit.c:1875 __do_sys_wait4+0x156/0x162 kernel/exit.c:1903 __se_sys_wait4 kernel/exit.c:1899 [inline] __riscv_sys_wait4+0x8a/0xd6 kernel/exit.c:1899 syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x3d8/0x56c arch/riscv/kernel/traps.c:343 handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:198 The buggy address belongs to the object at ffffaf801aba9980 which belongs to the cache pid of size 272 The buggy address is located 152 bytes inside of freed 272-byte region [ffffaf801aba9980, ffffaf801aba9a90) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9aba8 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xffe000000000040(head|node=0|zone=0|lastcpupid=0x7ff) page_type: f5(slab) raw: 0ffe000000000040 ffffaf8012293780 ffff8d80006ec800 dead000000000002 raw: 0000000000000000 0000000000150015 00000000f5000000 0000000000000000 head: 0ffe000000000040 ffffaf8012293780 ffff8d80006ec800 dead000000000002 head: 0000000000000000 0000000000150015 00000000f5000000 0000000000000000 head: 0ffe000000000001 ffff8d80006aea01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 12, tgid 12 (kworker/u8:0), ts 64693088700, free_ts 0 __set_page_owner+0x94/0x4c4 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfc/0x1c4 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x8e0/0x36b0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x22e/0x211a mm/page_alloc.c:5210 alloc_pages_mpol+0x1fa/0x5be mm/mempolicy.c:2486 alloc_frozen_pages_noprof+0x174/0x2f0 mm/mempolicy.c:2557 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x370/0x438 mm/slub.c:3302 ___slab_alloc+0xda6/0x1a3c mm/slub.c:4656 __slab_alloc.constprop.0+0x72/0x118 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] kmem_cache_alloc_noprof+0x334/0x80e mm/slub.c:5270 alloc_pid+0xd8/0x12fe kernel/pid.c:183 copy_process+0x408e/0x748e kernel/fork.c:2237 kernel_clone+0x128/0xdb0 kernel/fork.c:2651 user_mode_thread+0xd0/0x10c kernel/fork.c:2727 call_usermodehelper_exec_work kernel/umh.c:171 [inline] call_usermodehelper_exec_work+0xd4/0x1ac kernel/umh.c:157 process_one_work+0x96a/0x1f3a kernel/workqueue.c:3257 page_owner free stack trace missing Memory state around the buggy address: ffffaf801aba9900: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffffaf801aba9980: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffffaf801aba9a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffffaf801aba9a80: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffffaf801aba9b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report is generated by a bot. 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