From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DEE75355817; Tue, 6 Jan 2026 17:45:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767721523; cv=none; b=oWOOu/FNT9BWqKqzs09ZiCLkuGUpjLt6/XmlRyD9P8S7JRaniuBiKwVJu6qK0ji5vNzhhspLdhnQ4mWMJxmYx5VssZawzQtMYt3hyytCuAwlt0Y8E+Q1c3vMOY1PyPueVWfCiusSWl43MelDotNNd59GHDL3A1EVzNz2dlTUTn8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767721523; c=relaxed/simple; bh=Y4u+EkoUASIgPTs36oyPfCQ3UuqYxRtIz+5oj24e5g0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SpHNoPGSqssMbh0fMJ6diJv4aqGn0c8FV4RY/1Enq+ntJaArwCJ20MupMg/FSdNZEwHZG7lOPMM1ahHXD7NMWF3dU8eH8ACBavbs8VYcZgQsCyIfhW/oiifUw2vp8/34laiEw09ZYu6P+XwxQoX1q0gXIiw3UnBXMkyxx7q5gXs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=gqk6TKPc; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="gqk6TKPc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41B67C116C6; Tue, 6 Jan 2026 17:45:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1767721522; bh=Y4u+EkoUASIgPTs36oyPfCQ3UuqYxRtIz+5oj24e5g0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gqk6TKPc7dVRTqR4e949oc4ECwQwSRe8tdbZNcPlK4qpOMljmeenfgin+FusgeTAa /l1EXQU613XUsog/RK1BKZD5DXxJ4I9HwzOP0TkMeiWlNOl3It+8ClcDl06Ab/TzCv BdD+QePrxvDLfZBwXuayqmmY4Fe5kjBrlgDBXUVA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jakub Kicinski , Zqiang , Paolo Abeni , Harshit Mogalapalli Subject: [PATCH 6.12 529/567] usbnet: Fix using smp_processor_id() in preemptible code warnings Date: Tue, 6 Jan 2026 18:05:11 +0100 Message-ID: <20260106170510.964268694@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260106170451.332875001@linuxfoundation.org> References: <20260106170451.332875001@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zqiang [ Upstream commit 327cd4b68b4398b6c24f10eb2b2533ffbfc10185 ] Syzbot reported the following warning: BUG: using smp_processor_id() in preemptible [00000000] code: dhcpcd/2879 caller is usbnet_skb_return+0x74/0x490 drivers/net/usb/usbnet.c:331 CPU: 1 UID: 0 PID: 2879 Comm: dhcpcd Not tainted 6.15.0-rc4-syzkaller-00098-g615dca38c2ea #0 PREEMPT(voluntary) Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120 check_preemption_disabled+0xd0/0xe0 lib/smp_processor_id.c:49 usbnet_skb_return+0x74/0x490 drivers/net/usb/usbnet.c:331 usbnet_resume_rx+0x4b/0x170 drivers/net/usb/usbnet.c:708 usbnet_change_mtu+0x1be/0x220 drivers/net/usb/usbnet.c:417 __dev_set_mtu net/core/dev.c:9443 [inline] netif_set_mtu_ext+0x369/0x5c0 net/core/dev.c:9496 netif_set_mtu+0xb0/0x160 net/core/dev.c:9520 dev_set_mtu+0xae/0x170 net/core/dev_api.c:247 dev_ifsioc+0xa31/0x18d0 net/core/dev_ioctl.c:572 dev_ioctl+0x223/0x10e0 net/core/dev_ioctl.c:821 sock_do_ioctl+0x19d/0x280 net/socket.c:1204 sock_ioctl+0x42f/0x6a0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f For historical and portability reasons, the netif_rx() is usually run in the softirq or interrupt context, this commit therefore add local_bh_disable/enable() protection in the usbnet_resume_rx(). Fixes: 43daa96b166c ("usbnet: Stop RX Q on MTU change") Link: https://syzkaller.appspot.com/bug?id=81f55dfa587ee544baaaa5a359a060512228c1e1 Suggested-by: Jakub Kicinski Signed-off-by: Zqiang Link: https://patch.msgid.link/20251011070518.7095-1-qiang.zhang@linux.dev Signed-off-by: Paolo Abeni [Harshit: Resolved conflicts due to missing commit: 2c04d279e857 ("net: usb: Convert tasklet API to new bottom half workqueue mechanism") in 6.12.y] Signed-off-by: Harshit Mogalapalli Signed-off-by: Greg Kroah-Hartman --- drivers/net/usb/usbnet.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -702,6 +702,7 @@ void usbnet_resume_rx(struct usbnet *dev struct sk_buff *skb; int num = 0; + local_bh_disable(); clear_bit(EVENT_RX_PAUSED, &dev->flags); while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) { @@ -710,6 +711,7 @@ void usbnet_resume_rx(struct usbnet *dev } tasklet_schedule(&dev->bh); + local_bh_enable(); netif_dbg(dev, rx_status, dev->net, "paused rx queue disabled, %d skbs requeued\n", num);