From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.167.199 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793040229; b=sVDFCtYl1EM2U3Y6lfy5s4F2+9z0j5/Ms4hNmlU5josG3kKfQpelojBx7+Unsz8VDWKk BM/VeF11erOvJGqspxWamVGjG2ECfzo+EZM+63rceR4JhQ+uY8NUmAZ5WI3FaVAd8XIt4 mxBKWnTUr2RrCo7DVkb+m5V4Y//M4huPWuj8BkQ15JGyoNySMNhqA/fQZVGBRfV8fbkBr W69bPuKlqjqtpxZoJOaFV4zQFCAAQO0rwwGXrfzCTVUzOL4zAub5K/P60E99evTsqK3Mx TdTtgE8Tuu8/GB8McQDWeYMYmNKmxJn64FwID0h1X6meruezuYR2d1vEyVw1saVJSRg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793040229; h=DMARC-Filter:Received:X-Google-DKIM-Signature:X-Gm-Message-State: MIME-Version:X-Received:Date:X-Google-Appengine-App-Id: X-Google-Appengine-App-Id-Alias:Message-ID:Subject:From:To: Content-Type; bh=i4UzkNbvNTYKSyP4hKdp39ju0DTMoVudmB8zmNuX+3g=; b=VRcSojtPEP8APPP5bXjtOeL/0+KSc4HeprNOUCVSi6ndgVaSFCKvUdKpLUpfoMAUA/tr hGnpWORU00JWetQRal1Euc5FaWMuvr7ocRCP7fLFhM8Xodx+QvUc9iB4QVVCcgvL/Nh9E l/Eawr2kD18jfFHSND4ILyQ01NPbzLtxOWUNx2Pvyh0foQi/beiAW/pyfi6s5Lrc0w3Qw uBRCAi1v2etubRUiTrx/8913gk5VGr8ro9TNt1sSk85ZRG58ozg4WLdx/am0GlQ2I335K 13X3eBqGuxxIHoHveRMojZjUnFiVj+s69jX1Ju+OsasONuGGvzcNVN7NDAnDMFkQoUA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.remote-ip=209.85.167.199 Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8508D606A31D for ; Mon, 26 Oct 2026 18:43:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 8508D606A31D 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-oi1-f199.google.com with SMTP id 5614622812f47-4ea2c058e67so5477476b6e.1 for ; Mon, 26 Oct 2026 11:43:49 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1793040228; x=1793645028; 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=i4UzkNbvNTYKSyP4hKdp39ju0DTMoVudmB8zmNuX+3g=; b=emSsgPvJYKOZuQaT7juHbsEz9TmNAAYor0aTm0VS+IwMJ3vPJbsJwbWMdmxCOm+u3z 6r874Wv+NTOLikwQv+JRSPX8aB+XSEiFxhp9w2JxTeKcNWcHyAEWboNquQmUPNvZjOkY 8Q6BNopSM7yZv3MFAJlcS3HtbWYiDqhBXxLjQU/loOu/fcbplUFzmljAgcrcqd62Ffpr 8EPz5Smw516k8MwWzNaUWE2oeftNqJ+GIT9SsYOgZ5dZlsP2cltnTICUUzwn7ju7EJEY IhtefNHOiYZezzzgxrxeMsoiwRF23HvtEJCxqeiM1Ewt9A6afXYL005rdlJlPb0qsjXm XDnw== X-Gm-Message-State: AFq9FYIDQR7N61DAaYFU4nXDvrR6+mCW4KDnmDWoo2UC1CaWXTXV6hGs nuOAF0FAulPMR2gkijFKx/5vxtn1Tz8rQzkB4ynsaVRN3/R+G/vwKg9EWogS/wx+tb9RQTev/DB NxdageHMKCf76bDArKBE4dtvbERDXshWNjwAaXZ8O5qMNlir4nUyqnUQF0FM= X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-Received: by 2002:a05:6808:124d:b0:4f1:f700:d447 with SMTP id 5614622812f47-55c00377693mr4646304b6e.61.1793040228466; Mon, 26 Oct 2026 11:43:48 -0700 (PDT) Date: Mon, 26 Oct 2026 11:43:48 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6adf9f64.6200f071.51519.0ed1.GAE@google.com> Subject: [syzbot] [net?] KASAN: null-ptr-deref Read in netlink_has_listeners From: syzbot To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: c03c1a14507d Linux 7.3 git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git console output: https://syzkaller.appspot.com/x/log.txt?x=13a01ae1580000 kernel config: https://syzkaller.appspot.com/x/.config?x=4ccb65e03706547e dashboard link: https://syzkaller.appspot.com/bug?extid=1269fe6cc2016008124e compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11515031580000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1269fe6cc2016008124e@syzkaller.appspotmail.com ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:82 [inline] BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: null-ptr-deref in netlink_is_kernel net/netlink/af_netlink.c:88 [inline] BUG: KASAN: null-ptr-deref in netlink_has_listeners+0x3d/0x3f0 net/netlink/af_netlink.c:1390 Read of size 8 at addr 0000000000000578 by task syz-executor333/5617 CPU: 0 UID: 0 PID: 5617 Comm: syz-executor333 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 kasan_report+0x117/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200 instrument_atomic_read include/linux/instrumented.h:82 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] netlink_is_kernel net/netlink/af_netlink.c:88 [inline] netlink_has_listeners+0x3d/0x3f0 net/netlink/af_netlink.c:1390 genl_has_listeners include/net/genetlink.h:644 [inline] devlink_nl_notify_need net/devlink/devl_internal.h:238 [inline] devlink_port_notify+0x18c/0x520 net/devlink/port.c:559 __devlink_port_type_set+0x5f1/0x7a0 net/devlink/port.c:1237 devlink_port_netdevice_event+0x25d/0x3a0 net/devlink/port.c:-1 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] unregister_netdevice_many_notify+0x1a76/0x2140 net/core/dev.c:12580 unregister_netdevice_many net/core/dev.c:12635 [inline] unregister_netdevice_queue+0x2f5/0x340 net/core/dev.c:12436 unregister_netdevice include/linux/netdevice.h:3490 [inline] nsim_destroy+0x275/0x800 drivers/net/netdevsim/netdev.c:1198 __nsim_dev_port_del+0x14e/0x200 drivers/net/netdevsim/dev.c:1472 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1486 [inline] nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1710 nsim_drv_remove+0x58/0x170 drivers/net/netdevsim/dev.c:1725 device_remove drivers/base/dd.c:616 [inline] __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372 bus_remove_device+0x444/0x560 drivers/base/bus.c:664 device_del+0x524/0x8f0 drivers/base/core.c:3965 device_unregister+0x21/0xf0 drivers/base/core.c:4006 nsim_bus_dev_del drivers/net/netdevsim/bus.c:488 [inline] del_device_store+0x2b5/0x370 drivers/net/netdevsim/bus.c:244 kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb10e25df77 Code: 48 89 fa 4c 89 df e8 98 1e 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffd1f1777c0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000555587f6f400 RCX: 00007fb10e25df77 RDX: 0000000000000003 RSI: 00007fb10e29d08b RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd1f177938 R13: 0000000000000002 R14: 00007fb10e2c5c80 R15: 0000000000000002 ================================================================== --- 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 syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. 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