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 36B0051CF5E; Wed, 30 Sep 2026 18:23:33 +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=1790792614; cv=none; b=OEiFmMOluJlheXMVwGuwL0nnT5Ky5Jocw8UHE9ZugQXXwB8628IYI/xU0n36/9riGQ4ZYTZstyYo3crLLKJ+RFr9sij3Cy3XJdsDYr74x/qp6//pMlCqYpdq2Kq3PZyzRuXbca3f4tnfxvPODWpIuIgbhMcOzUBJQ4JAtTRQCTw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790792614; c=relaxed/simple; bh=qfAJOO3ZwX7eM9k2XSfAFvO+FEROEitbLvLqYIy7s2I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SfRwimnvra559DPbrP0ljxT5IXyLHiBy59+pJ2OlblaWWIP6f4dTgltFVS0d9VOWy4iizCFOHZLxkI/sG3odWc06IU3fJ0iQ2wiAFtRJKhVbxaQ/mPOhL/pWeQ9YwVFVT6rKEKsPgSy8cPRYDbyFz2L6KP54AzoX/PGBu87ijYY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MbeMMRF9; 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="MbeMMRF9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90EB71F000FF; Wed, 30 Sep 2026 18:23:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790792613; bh=bCoxazYj/rreklOtDInScJrehnh+t8dG35ikzG8Eamg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MbeMMRF9myDQ28KyMLiPxegC2S/Vgm0rHkC43klkUNWbVQouf43EDgpXmRH0vqKGg 0LBimYsvj/rWThIeEXLSZZo2naMKkBfVYp8MMvZ3e0CVvc+Wkywl41p0aPOwXxJI66 mZuHauqKlABkG2qXd7UrRyduW8qnl1AN77HoKrV0= 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 5.15 718/752] net: arp: terminate device name before lookup Date: Wed, 30 Sep 2026 17:29:48 +0200 Message-ID: <20260930152413.760935052@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152358.131179731@linuxfoundation.org> References: <20260930152358.131179731@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 5.15-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 @@ -1201,6 +1201,7 @@ 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;