From patchwork Tue Oct 10 21:07:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Justin Stitt X-Patchwork-Id: 13416154 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 28129156D3 for ; Tue, 10 Oct 2023 21:08:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="yH7JNjCG" Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C37609B for ; Tue, 10 Oct 2023 14:08:00 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-5a7aa161b2fso28946807b3.2 for ; Tue, 10 Oct 2023 14:08:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1696972080; x=1697576880; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=ndlPGfYsR5FrdEZ+vU/Zj3bD+kBDGYy33Ae6WjfGffY=; b=yH7JNjCGblBJnpFGem+LJ0XJ46VVdoQ8IFy1TPq5B/CXj96sbF05KjMW8+hD1cSwrj LzdCJWSnVCNcZUsPQZB9QArlCV1Niq0YfaXz/j4c8pQWXLQYBswKq8RVblq5N8+d92ZV pw+O4IeIVAgmgXigzueKgaTYrX77fiXP4NdAACB+zKPnzUTwhyvwOKI7kgFhd4sG09pQ 1j2EiCxGFOtc36v//Mv3yOSGyo1TSAL33uTkCWqVH6SZxrkDB1t2feYKL3sXKoUL/zav a1smD6ldyJIFYI8MaCrY2aCZY1KAVNFAUPNbSe9u+yfBOX1QQ3cQoTERj55dQvJ2gnv1 pAGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696972080; x=1697576880; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=ndlPGfYsR5FrdEZ+vU/Zj3bD+kBDGYy33Ae6WjfGffY=; b=aeJ7WLwtcTYti/D6U51k90iw+5F9m/U58UfmwALNCKEkaRZ7oUgKImMlUrqkEqdDc/ n626SNsND+Yd7IK8pVoQAmlMuGwhCyQFC3IMoEtOnzQ3eksiWFR+Hc9eTFuVHZvw6pY7 khgjfexdjbHs2Z8xHoT1X6oPZrQF35vAGNZnMgnE+lR6DP9h2kc3m/VEJNmlq+H6ZI4I t8HhC4qlRSohu6bQor1SZWqFD8OxDZYQjJNZ4AY8EQSgXqkKCcwpmGe0mXmaYMkWiERA 4Pvi97AqbaoEGDXm1e8VFsDmzE2VgFDjkn0kv5JH+Cb1oEJ1gN2EsMFjmnX21yjvN8Gh 7Dog== X-Gm-Message-State: AOJu0Yw6sxflyz5Tln/tGcJ4a81CbU6R/jGCbpmE8pPlHHnIZ9sJFvMD J+zcLE+SDcth7gufIZclg/DQ8CovAeiY61ndvw== X-Google-Smtp-Source: AGHT+IHj9mcr3yN9cr0pAbeqwrfthhwiz6e+OtQon8JznMOo9KT/dvFu6WV/L5M0mXZjtD1IJkgEjwfrm/dmYR4P9g== X-Received: from jstitt-linux1.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:23b5]) (user=justinstitt job=sendgmr) by 2002:a25:69d4:0:b0:d9a:58e1:bb52 with SMTP id e203-20020a2569d4000000b00d9a58e1bb52mr58171ybc.6.1696972080036; Tue, 10 Oct 2023 14:08:00 -0700 (PDT) Date: Tue, 10 Oct 2023 21:07:59 +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=H4sIAC69JWUC/x2N0QrCMBAEf6XcswdJimD9FRFpk217oGe5hKKU/ rupDwM7LzsbZZgg07XZyLBKlrdW8aeG4tzrBJZUnYILrXfecS6mcflyMllhmRWFUWbYMUQLniz TcPB49aIceQjnDu0YLl1qqf4uhlE+/+btvu8/fpTvp4MAAAA= X-Developer-Key: i=justinstitt@google.com; a=ed25519; pk=tC3hNkJQTpNX/gLKxTNQKDmiQl6QjBNCGKJINqAdJsE= X-Developer-Signature: v=1; a=ed25519-sha256; t=1696972079; l=2221; i=justinstitt@google.com; s=20230717; h=from:subject:message-id; bh=flnqc77MqO1c7xUbgevXQV3iKIfkAbCA1etAFyGMSlA=; b=L1o+advtN54cbFa+xXqTVzRfB3SNNlR/1bgBEQXRIdYE2QN+ozFKD/Z7wyvk6nz8JnPbMksY9 tQcwMCs+e4lBLETRdzxOSlViiob55aevqxlvK6JogW8Evrv/bSkGeKc X-Mailer: b4 0.12.3 Message-ID: <20231010-strncpy-drivers-net-ethernet-intel-igb-igb_main-c-v1-1-d796234a8abf@google.com> Subject: [PATCH] igb: 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=ham 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 see that netdev->name is expected to be NUL-terminated based on its usage with format strings: | sprintf(q_vector->name, "%s-TxRx-%u", netdev->name, | q_vector->rx.ring->queue_index); Furthermore, NUL-padding is not required as netdev is already zero-allocated: | netdev = alloc_etherdev_mq(sizeof(struct igb_adapter), | IGB_MAX_TX_QUEUES); ... 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. 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/igb/igb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2 change-id: 20231010-strncpy-drivers-net-ethernet-intel-igb-igb_main-c-b259e3f289d3 Best regards, -- Justin Stitt diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 76b34cee1da3..9de103bd3ad3 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -3264,7 +3264,7 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) igb_set_ethtool_ops(netdev); netdev->watchdog_timeo = 5 * HZ; - strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1); + strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name)); netdev->mem_start = pci_resource_start(pdev, 0); netdev->mem_end = pci_resource_end(pdev, 0);