From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f80.google.com (mail-ot1-f80.google.com [209.85.210.80]) (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 EEA8439B4A1 for ; Mon, 17 Aug 2026 08:18:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786954711; cv=none; b=JBoPcX+QgktxMeeEMH9FqM7xMGdIYaF90ZIehpqReQupLAONIOCQl/k4ZLXt+RcANptLdm6yq2tFCrU1SdFTydrtbZY0NKA7q0cUxiIe3jzyMKVLqXAa9cUHDFxXnV/nJLSC5puR9yUA2/FHOaSKkvRoZhkfmYIZEgWzTNWfocs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786954711; c=relaxed/simple; bh=2WRU1LAzDFQyr736YMDPBWPgkK848UlvDaSUKvjTYTE=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=qNOBIG5AVBuCAKfKrIjqaJgbrcH0k7hD+3bxDoMSEQGwS8uZWJwMu1/5qq7SpBzVX/iLvL7riKA4kFFYDqElFRFGHfnd+9GAq/y4pTLz+CNs4DCtKBY5HfT+DdxObcMGG/dq7JnwDJX2GsoR5A1XZh5uM1NPZa8bGDxw3rhw774= 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=209.85.210.80 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-ot1-f80.google.com with SMTP id 46e09a7af769-7ec6685adabso4805584a34.0 for ; Mon, 17 Aug 2026 01:18:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786954709; x=1787559509; 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=0FaO1QCRnZnkA6shIYBBdncSnDkqPEYWvnlXGGxQbHA=; b=ns2FxW3hf/mKkI8SXjsypzfdJkeocuLNH4IXnOQ7YweCPNr5f4dbVD68fnlmU8pxhz 6sfEr5oHkmOUUbu6IV9AChYTRbDoMnxpzTeCT6NhCllqrTSHFymUJB6D62pOOzFuT6IF c2Q95UzMnMoWtxBAGKtQtkYXAU0tjHsh1/BYjmb3nXoMEmSmHFwhQYI5dwLFD9gbBby8 4yuTq1uTBotmf4H3uWDzzS5z4IhAYZ98UB3uxhpgaFf93PzMg0Y6Zp6BGN5PQEw0ttFJ Dk+vbUTKwuR1xpAnWiAAnRCMgq09xaO7Lx0cJDFEPTogrFHeV4VuCBlpIvjc/su/0eSz MayA== X-Forwarded-Encrypted: i=1; AHgh+RqZu2NVk4/+leOJLPf70fBMu5g5HkoG1oTq/ntsavCCpdLnCw4G+8D3d0tm+D9yRHzBJ4xpkypGMbTKjCI=@vger.kernel.org X-Gm-Message-State: AOJu0YwG6Y2oqHxrFPHQafnGM/jzZi2db3qKhpWuzJCel5YbAQiwTcWH nEaTQrxpdMnfYEVuEegShAXLjbgKhaQscqa2AFj88Rxk+AOKAVjiAoYpsJIkLZlDpqR5W3qMjsv /NLKT1N47wcjcbYbPG3JwmppPo0prnRZRRY+iz3L1KiirvA649B2MxxShlCo= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:220c:b0:6ac:b5ae:65cb with SMTP id 006d021491bc7-6b0d618d1fdmr20728409eaf.14.1786954708884; Mon, 17 Aug 2026 01:18:28 -0700 (PDT) Date: Mon, 17 Aug 2026 01:18:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a82c3d4.f7a79266.2f965f.0024.GAE@google.com> Subject: [syzbot] [net?] KASAN: slab-use-after-free Read in nla_put_napi_id From: syzbot To: davem@davemloft.net, edumazet@google.com, horms@kernel.org, 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: 21d6ac051080 Merge branch 'for-next/core' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=169646c6580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3 dashboard link: https://syzkaller.appspot.com/bug?extid=483a6efbc4882c1201ee compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/88380e2ddcb9/disk-21d6ac05.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5dba5c2896b7/vmlinux-21d6ac05.xz kernel image: https://storage.googleapis.com/syzbot-assets/52ac739e37e0/Image-21d6ac05.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+483a6efbc4882c1201ee@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in nla_put_napi_id+0x140/0x144 net/core/netdev-genl.c:386 Read of size 4 at addr ffff0000c1da598c by task syz.3.236/6054 CPU: 0 UID: 0 PID: 6054 Comm: syz.3.236 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 __asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380 nla_put_napi_id+0x140/0x144 net/core/netdev-genl.c:386 netdev_nl_queue_fill_one+0x3ac/0x610 net/core/netdev-genl.c:494 netdev_nl_queue_dump_one+0xd0/0x2f8 net/core/netdev-genl.c:603 netdev_nl_queue_get_dumpit+0x1e0/0x4a4 net/core/netdev-genl.c:641 genl_dumpit+0x108/0x1bc net/netlink/genetlink.c:1026 netlink_dump+0x55c/0xb6c net/netlink/af_netlink.c:2331 __netlink_dump_start+0x4c4/0x6f8 net/netlink/af_netlink.c:2446 genl_family_rcv_msg_dumpit+0x1a8/0x28c net/netlink/genetlink.c:1075 genl_family_rcv_msg net/netlink/genetlink.c:1191 [inline] genl_rcv_msg+0x404/0x620 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2556 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg+0xc8/0x17c net/socket.c:790 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2684 ___sys_sendmsg+0x198/0x224 net/socket.c:2738 __sys_sendmsg+0x158/0x204 net/socket.c:2770 __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2773 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 Allocated by task 12: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e8/0x5ec mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] nsim_queue_alloc+0x58/0x120 drivers/net/netdevsim/netdev.c:715 nsim_queue_init drivers/net/netdevsim/netdev.c:1012 [inline] nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1059 [inline] nsim_create+0x7e0/0xcf4 drivers/net/netdevsim/netdev.c:1152 __nsim_dev_port_add+0x59c/0x95c drivers/net/netdevsim/dev.c:1509 nsim_dev_port_add_all+0x50/0x114 drivers/net/netdevsim/dev.c:1570 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1622 [inline] nsim_dev_reload_up+0x3cc/0x5b4 drivers/net/netdevsim/dev.c:1058 devlink_reload+0x3b0/0x64c net/devlink/dev.c:475 devlink_pernet_pre_exit+0x1ac/0x30c net/devlink/core.c:560 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0x158/0x81c net/core/net_namespace.c:234 cleanup_net+0x474/0x6c4 net/core/net_namespace.c:702 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838 Freed by task 5937: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_free_info+0x54/0x6c mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x188/0x690 mm/slub.c:6692 nsim_queue_free+0x11c/0x1a0 drivers/net/netdevsim/netdev.c:735 nsim_queue_mem_free+0xfc/0x130 drivers/net/netdevsim/netdev.c:796 netdev_rx_queue_reconfig+0x2dc/0x48c net/core/netdev_rx_queue.c:-1 netdev_rx_queue_restart+0xa4/0xec net/core/netdev_rx_queue.c:183 nsim_qreset_write+0x30c/0x48c drivers/net/netdevsim/netdev.c:887 full_proxy_write+0x11c/0x160 fs/debugfs/file.c:388 vfs_write+0x2a4/0xa0c fs/read_write.c:685 ksys_write+0x12c/0x228 fs/read_write.c:739 __do_sys_write fs/read_write.c:750 [inline] __se_sys_write fs/read_write.c:747 [inline] __arm64_sys_write+0x84/0x98 fs/read_write.c:747 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 The buggy address belongs to the object at ffff0000c1da5800 which belongs to the cache kmalloc-cg-1k of size 1024 The buggy address is located 396 bytes inside of freed 1024-byte region [ffff0000c1da5800, ffff0000c1da5c00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff0000c1da7000 pfn:0x101da0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff0000c1da0411 flags: 0x5ffc00000000240(workingset|head|node=0|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 05ffc00000000240 ffff0000c000b280 fffffdffc3c5e410 fffffdffc35ae210 raw: ffff0000c1da7000 000008000010000f 00000000f5000000 ffff0000c1da0411 head: 05ffc00000000240 ffff0000c000b280 fffffdffc3c5e410 fffffdffc35ae210 head: ffff0000c1da7000 000008000010000f 00000000f5000000 ffff0000c1da0411 head: 05ffc00000000003 fffffdffc3076801 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000c1da5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c1da5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000c1da5980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000c1da5a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c1da5a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- 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