From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 4FCB251FCDA; Wed, 30 Sep 2026 17:31:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790789520; cv=none; b=CbN7sdWGOPQknZjfLJ7y3j1rNIJEgnld+S6skpr0XeP5BLIB5SkOTpeM1CHUSmlrgh5thVcgz6v9WXb04QGHg+HGxzp0N66ZMJ/iN+r/rJeUDb+NhrzvReRJwyjGGUgBTs+PoHMQEFFFVoiaU2pv5NiKHUD0fhIcH2UQLNx6w68= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790789520; c=relaxed/simple; bh=N8nPL0/Ce3AsUugcs8lLlEp9VYBikF0cHfiMyS00UkE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=o7zv06Iwk5ous89infGEMlOY6hUuCawKQH3cv+Y45s6Pu/5jjTgTPsWxEq3yBdiE/U+gCGKocE7UCLyzq2lYEqWNgPeTPyamOcY9aFjRCo5stNq4sqnmqYlG2G007rtPaTjnKg2EvVUypLafru+ghXlmi9EN0NYYVLmeBx8041U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=v3Tk049W; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="v3Tk049W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 65A5F1F000FF; Wed, 30 Sep 2026 17:31:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790789518; bh=+XFEKdLUgL5BAyBMnTKsjTZQY8C/rSPN3VSe0UEaCRI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=v3Tk049WyNs0/fBorEnJBYN1jz1Z1TI97ydhwo6qTF8EFCXeJU3fTgTP7b6/HvvdB PCKZadlItM7bmwcSVBUvoITeIlUolUsa1d3kHQnwY6Trq+EBs7tcNjbe8Rzj6o1c3+ 6+2D/lJEhPiNMbi3pn5c514wR7uNBdSYv7ImtAYE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vega , Zijie Huang , Ren Wei , Ido Schimmel , Jakub Kicinski Subject: [PATCH 6.12 507/877] net: arp: terminate device name before lookup Date: Wed, 30 Sep 2026 17:23:38 +0200 Message-ID: <20260930152425.601459461@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152414.738996857@linuxfoundation.org> References: <20260930152414.738996857@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev 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: Zijie Huang commit d8b6529e80bcb4fb8177121404cbb3377acaebd2 upstream. The ARP ioctl copies a user-provided struct arpreq into a stack object. Its arp_dev field may contain IFNAMSIZ bytes without a NUL terminator. Such input is passed to dev_get_by_name_rcu() or __dev_get_by_name(), where strcmp() can read past the end of the stack object when a matching alternative interface name exists. Terminate the field before the lookup to prevent the out-of-bounds read. Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames") Cc: stable@vger.kernel.org Reported-by: Vega Signed-off-by: Zijie Huang Signed-off-by: Ren Wei Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/fabf02a70787d17299e4b3153eadffaf20d154b3.1789910973.git.milkory@outlook.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/ipv4/arp.c | 1 + 1 file changed, 1 insertion(+) --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -1276,6 +1276,7 @@ int arp_ioctl(struct net *net, unsigned err = copy_from_user(&r, arg, sizeof(struct arpreq)); if (err) return -EFAULT; + r.arp_dev[IFNAMSIZ - 1] = '\0'; break; default: return -EINVAL;