From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f78.google.com (mail-oo1-f78.google.com [209.85.161.78]) (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 6453C35200F for ; Tue, 16 Jun 2026 14:05:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781618726; cv=none; b=psa7xZ1dUZm9rgLrStWnYQXfnXg/cn5kMmhDnmJahsxRRELs9c7UkaeK5c7U9RTcbZQMLzQWHfXfEvI3hFkVdoU5WC7GVgMKTdLjBmroYweqLRJWIEUSWXp+Sacvz51+Gglj1KnS8scD6lf7B4aVrWRfvAElzgEs8FK7B1Bdg6o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781618726; c=relaxed/simple; bh=Jd9Mqn7mX4TGbx50KPjO0Nxkuakmg1tuw0TOoALqVHU=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=RHcoO/Ild+OrpaMhgWlui5D86Gpr1xi5yli1QyTtVR3iVbppIRXqYpFreHzmbtb8c3rcdRgpfS4aaXeiCJrMZd+CE0H3GXUq8o6s/GG0UYKTj97r810JPvGIFNYVQlW8Jtmza+qos+9SJCcml0w4VZK8Bj9Z/Cvg4HK6ZX599+o= 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=209.85.161.78 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-oo1-f78.google.com with SMTP id 006d021491bc7-69e96638382so3799140eaf.3 for ; Tue, 16 Jun 2026 07:05:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781618724; x=1782223524; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=79TiA5j8GUNDxPILUJjkK1bbZbE1hyJeSrB8fyNyi7Q=; b=BmY+pRwtS8RpuHkwy0Mhe/DNXe0pAMGoRnlxXp9QfwBuAV3e/pT05M/6m2UMcoSSM4 Y7cb/32ydOgxtbLMrD4uFAcZlOpGfN9d/XTREmZ9+eYPhZGne9lUdkpjgCUpy1yx5upj r/JmTGx8187YH5XppimD2TLmoJ7W1nRLY5Now7ZsesmBXJbWJOBBZQYAL/2+X4C9Fslp nioizuml5C9P9M3CzYCUrMxQAEcHSUi5tRdBgnWUfjSRoCmazzv4YywkLHsa1frxWl0w ahz7hgivW4LpiY4oJoH0G/T3R597oGImMwihHTi8wh+mB0J3RBYm5bCpLrCzuzLPUvG7 31jQ== X-Forwarded-Encrypted: i=1; AFNElJ9LZjsda/98eafU7PM1zzV/dkHzECoknSY4nGnxCFqr9OfEFJU59f8u+PS9CKwJy9q4X9jvuYgPfzHnR5Y=@vger.kernel.org X-Gm-Message-State: AOJu0YwdMr++VCF64OD1pKuyZrkdiYHw4daf0vjyAKw/ytAp4rDcyG6D XV0mUSSVahaftSPy8BniqzN7WFlKQYdh5ua9MKYdnT7PMliJof2TK0RCbciqQA78Dsy1Mru3Are wxwg8zwKlymSoe+2WnNRDoZqzeomM6Dig/q8Kl9BxVAIahE8z6TH+qR14EZ8= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:6ad0:b0:69e:57a1:892a with SMTP id 006d021491bc7-69eecacca8amr9641260eaf.55.1781618724333; Tue, 16 Jun 2026 07:05:24 -0700 (PDT) Date: Tue, 16 Jun 2026 07:05:24 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a315824.b0403584.28d0ff.0000.GAE@google.com> Subject: [syzbot] [net?] KASAN: slab-use-after-free Read in fib_rules_lookup From: syzbot To: davem@davemloft.net, dsahern@kernel.org, edumazet@google.com, horms@kernel.org, idosch@nvidia.com, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 72dfa4700f78 net: dsa: sja1105: fix lastused timestamp in .. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=15794bd2580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a0842261b62cdea8 dashboard link: https://syzkaller.appspot.com/bug?extid=965506b59a2de0b6905c compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d4e16f50a97c/disk-72dfa470.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6cd4a736e796/vmlinux-72dfa470.xz kernel image: https://storage.googleapis.com/syzbot-assets/548b0011c8e8/bzImage-72dfa470.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+965506b59a2de0b6905c@syzkaller.appspotmail.com bond0 (unregistering): Released all slaves bond1 (unregistering): Released all slaves bond2 (unregistering): (slave dummy0): Releasing active interface bond2 (unregistering): Released all slaves ================================================================== BUG: KASAN: slab-use-after-free in fib_rules_lookup+0x15e/0xeb0 net/core/fib_rules.c:321 Read of size 8 at addr ffff88804ec4c680 by task kworker/u8:21/12641 CPU: 0 UID: 0 PID: 12641 Comm: kworker/u8:21 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: netns cleanup_net Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 fib_rules_lookup+0x15e/0xeb0 net/core/fib_rules.c:321 __fib_lookup+0x106/0x210 net/ipv4/fib_rules.c:96 ip_route_output_key_hash_rcu+0x294/0x2720 net/ipv4/route.c:2811 ip_route_output_key_hash+0x18d/0x2a0 net/ipv4/route.c:2702 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2929 ip4_datagram_release_cb+0x89d/0xbe0 net/ipv4/datagram.c:118 release_sock+0x206/0x260 net/core/sock.c:3861 inet_shutdown+0x2b1/0x390 net/ipv4/af_inet.c:950 udp_tunnel_sock_release+0x6d/0x80 net/ipv4/udp_tunnel_core.c:197 fou_release net/ipv4/fou_core.c:562 [inline] fou_exit_net+0x17d/0x1f0 net/ipv4/fou_core.c:1230 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x43d/0x8d0 net/core/net_namespace.c:252 cleanup_net+0x572/0x810 net/core/net_namespace.c:702 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 19121: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5296 [inline] __kmalloc_node_track_caller_noprof+0x4d7/0x7b0 mm/slub.c:5408 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:763 [inline] fib_rules_register+0x2f/0x400 net/core/fib_rules.c:170 fib4_rules_init+0x21/0x160 net/ipv4/fib_rules.c:508 ip_fib_net_init net/ipv4/fib_frontend.c:1578 [inline] fib_net_init+0x17a/0x3e0 net/ipv4/fib_frontend.c:1628 ops_init+0x35d/0x5d0 net/core/net_namespace.c:137 setup_net+0x118/0x350 net/core/net_namespace.c:446 copy_net_ns+0x4f9/0x720 net/core/net_namespace.c:579 create_new_namespaces+0x3f0/0x6b0 kernel/nsproxy.c:132 unshare_nsproxy_namespaces+0x149/0x190 kernel/nsproxy.c:234 ksys_unshare+0x57d/0xa00 kernel/fork.c:3242 __do_sys_unshare kernel/fork.c:3316 [inline] __se_sys_unshare kernel/fork.c:3314 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3314 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 12641: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] __rcu_free_sheaf_prepare+0x12d/0x2a0 mm/slub.c:2940 rcu_free_sheaf+0x31/0x200 mm/slub.c:5850 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2869 handle_softirqs+0x225/0x840 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 unregister_netdevice_many_notify+0x1874/0x2150 net/core/dev.c:12445 ops_exit_rtnl_list net/core/net_namespace.c:187 [inline] ops_undo_list+0x391/0x8d0 net/core/net_namespace.c:248 cleanup_net+0x572/0x810 net/core/net_namespace.c:702 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88804ec4c600 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 128 bytes inside of freed 192-byte region [ffff88804ec4c600, ffff88804ec4c6c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4ec4c flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88813fe163c0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 13856, tgid 13853 (syz.3.2144), ts 351172300879, free_ts 351133053454 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x24ae/0x2530 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x336/0x3d0 mm/slub.c:7272 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x320/0x720 mm/slub.c:4652 alloc_from_pcs mm/slub.c:4750 [inline] slab_alloc_node mm/slub.c:4884 [inline] __do_kmalloc_node mm/slub.c:5295 [inline] __kmalloc_noprof+0x464/0x750 mm/slub.c:5308 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] new_dir fs/proc/proc_sysctl.c:966 [inline] get_subdir fs/proc/proc_sysctl.c:1010 [inline] sysctl_mkdir_p fs/proc/proc_sysctl.c:1320 [inline] __register_sysctl_table+0xc02/0x1370 fs/proc/proc_sysctl.c:1395 neigh_sysctl_register+0x9b1/0xa90 net/core/neighbour.c:3915 addrconf_sysctl_register+0xb3/0x1c0 net/ipv6/addrconf.c:7396 ipv6_add_dev+0xd26/0x13a0 net/ipv6/addrconf.c:460 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3679 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline] call_netdevice_notifiers net/core/dev.c:2302 [inline] register_netdevice+0x18db/0x1f00 net/core/dev.c:11474 macsec_newlink+0x706/0x1200 drivers/net/macsec.c:4218 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3905 page last free pid 12657 tgid 12657 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0xc0d/0xd20 mm/page_alloc.c:2938 __tlb_remove_table_free mm/mmu_gather.c:228 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:291 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2869 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Memory state around the buggy address: ffff88804ec4c580: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804ec4c600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804ec4c680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff88804ec4c700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88804ec4c780: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ================================================================== --- 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 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