From patchwork Tue Oct 10 21:15:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Justin Stitt X-Patchwork-Id: 13416164 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 80D33315B9 for ; Tue, 10 Oct 2023 21:15:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="OFwT5hzx" Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4085F98 for ; Tue, 10 Oct 2023 14:15:41 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-d85fc108f0eso8242831276.2 for ; Tue, 10 Oct 2023 14:15:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1696972540; x=1697577340; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=inAfHUFES32Bj4C70GcKsE711OPK+t9RMjXtNQ5VszM=; b=OFwT5hzx701CknF/AANYsdyGw6qzpWUZE+ZSQAT0kcVyFNQ0GkGtzp8zYWa+f9d0tM S++c9qb12muBlIC8UWne3c8pegtAvr9BLz7oaY7z54Mjny8duoAZmgTi6KYScJSD85gJ n2/iG4w9osWjs4oLszpbl6kAoDCUr2hlwclwtURYrHfK4Maz8RQDtLzDd1EM9KcGQocD JvB2fvQp+QRKCXSIFP8KrInMZ6AdfnNBBcKAO52cyAoaP7bZ8oxBgxSbhhA90sD608Ha zK3LvttMWQ/uNFLnj57Y90agTZMyU71YJrYFPjx1jYJiChHUNOM9inckgMEfp6FMgARk Y1og== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696972540; x=1697577340; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=inAfHUFES32Bj4C70GcKsE711OPK+t9RMjXtNQ5VszM=; b=h4ox9mjyAGktJel62Evp0T4/c52azLmUY7ix0AlTeaL9uhWYNRkCic3VfZuRT6xw24 jb8tRhomUcmdv8/U40AnJDVCcJ3IYpr3vuFLF5zps+UCN9gkrMKIXCazOIfnRQZXbkhV Uu/0Y5P7coFe28NHABbDo3TOcClmDyAe47OBcPbHPoMLNwtcup59t1Z7RXdGTmGN+RfX J3D8lJxcjAlvgjYe0SXAGpDyOm4k8bFWXsDf8jUYLUht03Hwl5k9O5Mgb9USmvuhgimy UiBZfK3cZ5RBlOzzFukPkDzgDzvvyUqVcAK5SLGeUbhTjldfCQx6RTl34q51xQXt0gXI wRGA== X-Gm-Message-State: AOJu0Yx3lmM2lH4GQ5hXV7LRyIbsX1TXsaBv4bqKQYBjMVSYoYkDrREM aYHWWs3n5yyIUaCehlxZklfat67mt0IU1OBc0g== X-Google-Smtp-Source: AGHT+IEMUv1TTDgqzDOYIq+Sw2rvHfs+0t2AabsWyLXy1VIOnuqASlfBZBLu9OJtzGdOmIIJ59zdUH9JxiXKqaoZ5g== X-Received: from jstitt-linux1.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:23b5]) (user=justinstitt job=sendgmr) by 2002:a25:ac24:0:b0:d9a:3596:a5e8 with SMTP id w36-20020a25ac24000000b00d9a3596a5e8mr87331ybi.7.1696972540475; Tue, 10 Oct 2023 14:15:40 -0700 (PDT) Date: Tue, 10 Oct 2023 21:15:39 +0000 Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAPq+JWUC/x2N0QrCMBAEf6XcswdJREF/RURism0P9CyXUCql/ 27qw8DOy85KBSYodO1WMsxS5KNN/KGjNEYdwJKbU3Dh6J13XKppmr6cTWZYYUVl1BG2D9GKF8u Qdh7vKMqJwxl9DO6S8/NE7Xcy9LL8m7f7tv0AuewH3oMAAAA= X-Developer-Key: i=justinstitt@google.com; a=ed25519; pk=tC3hNkJQTpNX/gLKxTNQKDmiQl6QjBNCGKJINqAdJsE= X-Developer-Signature: v=1; a=ed25519-sha256; t=1696972539; l=2229; i=justinstitt@google.com; s=20230717; h=from:subject:message-id; bh=aszC9coJ3ufDFemnzGBEFSljINDMKfOjEfDt2TlDPEA=; b=M0LjBlQz4apy3gyX2tH8Osydptr9lDj/JzxqU4f3aGIPfDCpy48DUAn7/iUFhpQnXafN44Mnu 3bQ5fcJIVvbBVvaS1GZ/qGz8AcdS1uPFdCrtmQC0/k/kBHxCMuKuJiG X-Mailer: b4 0.12.3 Message-ID: <20231010-strncpy-drivers-net-ethernet-intel-igc-igc_main-c-v1-1-f1f507ecc476@google.com> Subject: [PATCH] igc: replace deprecated strncpy with strscpy From: Justin Stitt To: Jesse Brandeburg , Tony Nguyen , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: intel-wired-lan@lists.osuosl.org, 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_BLOCKED,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net `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 netdev->name to be NUL-terminated based on its use with format strings: | if (q_vector->rx.ring && q_vector->tx.ring) | sprintf(q_vector->name, "%s-TxRx-%u", netdev->name, Furthermore, we do not need NUL-padding as netdev is already zero-allocated: | netdev = alloc_etherdev_mq(sizeof(struct igc_adapter), | IGC_MAX_TX_QUEUES); ... alloc_etherdev() -> alloc_etherdev_mq() -> alloc_etherdev_mqs() -> alloc_netdev_mqs() ... | p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 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. Let's also opt for the more idiomatic strscpy usage of (dest, src, sizeof(dest)) instead of (dest, src, SOME_LEN). 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 --- Note: build-tested only. --- drivers/net/ethernet/intel/igc/igc_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2 change-id: 20231010-strncpy-drivers-net-ethernet-intel-igc-igc_main-c-26efa209ddb5 Best regards, -- Justin Stitt diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 98de34d0ce07..e9bb403bbacf 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -6935,7 +6935,7 @@ static int igc_probe(struct pci_dev *pdev, */ igc_get_hw_control(adapter); - strncpy(netdev->name, "eth%d", IFNAMSIZ); + strscpy(netdev->name, "eth%d", sizeof(netdev->name)); err = register_netdev(netdev); if (err) goto err_register;