From patchwork Thu Oct 12 21:53:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Justin Stitt X-Patchwork-Id: 152200 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2908:b0:403:3b70:6f57 with SMTP id ib8csp1517448vqb; Thu, 12 Oct 2023 14:53:21 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEUaRNMCL5mD9RgN28NwU148wzCntMtbDg6bptgu82SPvpoRQVVQXr02n/D5v3WnaQrOYti X-Received: by 2002:a17:902:e885:b0:1c0:bf60:ba82 with SMTP id w5-20020a170902e88500b001c0bf60ba82mr28534063plg.5.1697147601097; Thu, 12 Oct 2023 14:53:21 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1697147601; cv=none; d=google.com; s=arc-20160816; b=TZFihIH5MO6t7Zd4/dPkRYXYoIiXME/W0iG3y6p3IrEKRWSClrK8ksVnhRFL8cUlwT WDeJB55LvOaXdjLI7VDGc/pKxhK3Cr2J46DwtmbCjCLjNbINZIm7NSLZTxZDrUsiZHur EZSiA3At7X48epH924VqiOceYlMWGhexARTg30JA980UU7wvtgTB8yXqCWrJplQ+kdxI obnjtChQEyBsZjX8bwqnWn6usDOWqBUrWJIfxBII18O4/LDEg6La/j+3aVbbc+3NbiKO C0vajanH86eKn6hJ//ikzdeWaJ/DQTIcmtHfn8f/l6N30A59btIAK6ax4WQois+Q3M/b ifUQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:cc:to:from:subject:message-id:mime-version:date :dkim-signature; bh=YTkEOzvlwSRqd6Swcq6Hh8KnurUwVBxQe6czHRUN7YA=; fh=jNFzfs0LVcNPJYpz3MO9rP5uq1TU3TrcBg7mkF9EWrg=; b=QnrpUDzXI9rVQBA9FCvMFCXMaH8ecO5Dg2Yh/SvFdwLzr7CaJanND84vBF8+VDKXyS 7FWX3MOfgnu4URrSdPiGgs52o3k3FeZVN+ZofMQ4oDY1pcZPWlqf+FxN3boscovjZSq+ KTZ7EzQJiAKNFyZlsOoweWfmE7/Oh7ixECP4eP5a90IRkY5w44868d/QYWoNySyJSWu1 JsMguI/3xuvWjcszukiapNeC51WveaL4peEd16eDwMvmcfcXpd/0GbZmcuwshMtmyCXI V7ZebNT1SkI4JhKcvo8KCR1bjGs54/YofYiIMewM83H3sgEOI8n3gZ9vyhH57RlJUXYk YWWg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=FtNoL2no; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id d17-20020a170902c19100b001bdcd2e1706si1163553pld.196.2023.10.12.14.53.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Oct 2023 14:53:21 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=FtNoL2no; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 6A85882DD099; Thu, 12 Oct 2023 14:53:20 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1442949AbjJLVxH (ORCPT + 19 others); Thu, 12 Oct 2023 17:53:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1442911AbjJLVxG (ORCPT ); Thu, 12 Oct 2023 17:53:06 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3044DC0 for ; Thu, 12 Oct 2023 14:53:05 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-5a7bcbb95b2so22320307b3.3 for ; Thu, 12 Oct 2023 14:53:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1697147584; x=1697752384; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=YTkEOzvlwSRqd6Swcq6Hh8KnurUwVBxQe6czHRUN7YA=; b=FtNoL2noI3RqR2YnxNeaa8qvVLPTp1yVrdLnAP7wKepMJr2uoStoUFLVA/Ej1FRCx9 JBPTaJAo/FOU/AmLAsazfYh/exqjHQbu3ZHsg1hklq3LtQ7pnUePUXNjcaPrsr32CjI8 jfyGQCelOcGO6v0BYZTTm4nphF5qvkweVX7zuDuspmyOIgJDPKb/2YDqIFTrn2yxipVi U7mSTxQ1WxBTsusu8sCsKloCD2mIawIxKIVPL0S40zPeD1MC7EbArJfuMlVZ8/MOvV/4 rD5YAEfckx+VELw0saMifUBbrxLcQW0kk+y67uF7MTH3chKdcxngREoQKi1elLzfUEX6 qdxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697147584; x=1697752384; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=YTkEOzvlwSRqd6Swcq6Hh8KnurUwVBxQe6czHRUN7YA=; b=kKgGUBjGtYxSaLv3sp5JLpE2UVZSjz827+01A2MTB4BNlC0XEuA0nsRX3zFwEcO732 eoB4iGibBuSKxINZXNHdT55h2w+hNXPi3dlKe/UKbkoriYVIWDakQtkkEqnqMivkSYVa b8f8+MBaZxDgS/9Q88Z2HVTBfaPHRHXWaG2Zob/bkCC9Oxj8qkMpWNTnQUdMqWpYmoD/ Camv9Bz5ZG5nFMOh6K7JhT3fjCDFLLmErkeGxjclsBe2uI7JJcnrd6oK1BAAgeFlVtfw jDhfX1IymIP3Rl87H66zXg2ZtX5VW6ezIxMCrD3QFojMi/Tz5425PeUi2f7mrY0/0tHC rjqA== X-Gm-Message-State: AOJu0Yxs/MCTPGEp6uHPoiH8FPh0uOrid5+sg4OJ0K7enHiXaWh4r0nP HYCyg9n7Izj8GBfadd5oD5s4FttfWGCmF0xJnA== X-Received: from jstitt-linux1.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:23b5]) (user=justinstitt job=sendgmr) by 2002:a81:7e4c:0:b0:584:41a6:6cd8 with SMTP id p12-20020a817e4c000000b0058441a66cd8mr501646ywn.8.1697147584487; Thu, 12 Oct 2023 14:53:04 -0700 (PDT) Date: Thu, 12 Oct 2023 21:53:03 +0000 Mime-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAL5qKGUC/x3NQQqDMBBA0avIrDuQREJKryJSbDLWWTSGGZWKe HeDy7f5/wAlYVJ4NQcIbaw85wr7aCBOQ/4ScqoGZ1xrjXWoi+RYdkzCG4lipgXLtOMv8fz+rIo RzWCSp2fwwTqooSI08v+edP15Xjy38kl0AAAA X-Developer-Key: i=justinstitt@google.com; a=ed25519; pk=tC3hNkJQTpNX/gLKxTNQKDmiQl6QjBNCGKJINqAdJsE= X-Developer-Signature: v=1; a=ed25519-sha256; t=1697147583; l=1868; i=justinstitt@google.com; s=20230717; h=from:subject:message-id; bh=vdQUeoyWeauGUEEyEYmjpmzS6T1B4Kyza0zZ2VuUMVU=; b=08rcTE44cKhSckEbxhG3eLzKqTkBARP9qjlbUWs+AlqMspRHIZZZigeo48P5fBG2TNtbAKjvp D8L72jxZBnvDlw5D8Lnl4a3l+c5sqVGWu3+A9JBjMYWws5qQcY0Htn6 X-Mailer: b4 0.12.3 Message-ID: <20231012-strncpy-drivers-net-phy-mdio_bus-c-v1-1-15242e6f9ec4@google.com> Subject: [PATCH] net: mdio: replace deprecated strncpy with strscpy From: Justin Stitt To: Andrew Lunn , Heiner Kallweit , Russell King , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, Justin Stitt X-Spam-Status: No, score=-9.6 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Thu, 12 Oct 2023 14:53:20 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1779587628418813373 X-GMAIL-MSGID: 1779588243151961641 strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. We expect mdiodev->modalias to be NUL-terminated based on its usage with strcmp(): | return strcmp(mdiodev->modalias, drv->name) == 0; Moreover, mdiodev->modalias is already zero-allocated: | mdiodev = kzalloc(sizeof(*mdiodev), GFP_KERNEL); ... which means the NUL-padding strncpy provides is not necessary. Considering the above, a suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer without unnecessarily NUL-padding. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Andrew Lunn Reviewed-by: Kees Cook --- Note: build-tested only. Found with: $ rg "strncpy\(" --- drivers/net/phy/mdio_bus.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2 change-id: 20231012-strncpy-drivers-net-phy-mdio_bus-c-0a0d5e875712 Best regards, -- Justin Stitt diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 25dcaa49ab8b..6cf73c15635b 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -506,7 +506,7 @@ static int mdiobus_create_device(struct mii_bus *bus, if (IS_ERR(mdiodev)) return -ENODEV; - strncpy(mdiodev->modalias, bi->modalias, + strscpy(mdiodev->modalias, bi->modalias, sizeof(mdiodev->modalias)); mdiodev->bus_match = mdio_device_bus_match; mdiodev->dev.platform_data = (void *)bi->platform_data;