From patchwork Wed Aug 30 21:07:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Azeem Shaikh X-Patchwork-Id: 719327 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45FE2C83F01 for ; Wed, 30 Aug 2023 21:10:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240705AbjH3VKa (ORCPT ); Wed, 30 Aug 2023 17:10:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240443AbjH3VK3 (ORCPT ); Wed, 30 Aug 2023 17:10:29 -0400 Received: from mail-il1-f179.google.com (mail-il1-f179.google.com [209.85.166.179]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B263DE76; Wed, 30 Aug 2023 14:09:49 -0700 (PDT) Received: by mail-il1-f179.google.com with SMTP id e9e14a558f8ab-34ccedcc584so321245ab.0; Wed, 30 Aug 2023 14:09:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1693429661; x=1694034461; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=ofr1jYcnUdNDcThGOeqc7mheVMPv4mVGcLb0lf2Uv9c=; b=Zu39t0/OcKtwC+SPf80xR1v8iapM+UGPebWTs+7k+rG2PCfBWf2bC/wy1QUTM5yDib rdCb1ulPkm9vROGwEpxhExgNYSCda8tgPyTNnnVUYXnQMBhtBpflnsTzoQ4vUGkwfa1r H0Tf0X1mFodej2e0vHA1AKLSqb2YZ++InHVK8YrnxMEBadCUO+27M75CvkpJhX7I+bqK qxGFQTIZgb5yn2l5lSprUVVrjl3aVpWC1VrACTOcxiXFrlFW/Vg/ZNQmUNLrYe4HPe+6 ae2teLSBNNkx3uTRNZO3ggAkZD1WHynFmue+4FTjKsVIBISGooQlSTLDDH06JLtJJy4V azIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693429661; x=1694034461; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=ofr1jYcnUdNDcThGOeqc7mheVMPv4mVGcLb0lf2Uv9c=; b=EbiE+SifZNrMYmVmjt2/QyU3C4TQnmsYOTA+fk2sAZZKlUfEG6Z50O3+hU8dcGaEOc MMw/a9HRAIneS3w2lO64AXiDbIllIenqRYsMFE7gxwXvCFDcQ1sYOhpW0qC7i4bV/cYE zbxqpesww+YzcAfRCdYJgTbfjrmo+DoGgfjnjd5abrkFklJbQ5US2xLRppe/3X1mpQEe eq84kPLbhH6LbTp2oklP5T+Au/YZTPQctFGtH9oKnFAxbosKp60tDg5Gv+5zhEr8V3X5 NioxUUpEhiPzf4HM13I/fe37xxMckJX8Hbbc378URkYE/nLmz55J+EFgYuHGNmHl/06X fgeg== X-Gm-Message-State: AOJu0YzPkMjmuLpJMjFx/8ByV2LmiEf+YQyWZWM9ZDIdeDBUnREt/CgF aWj1qfZwLrCAMKpGmjEVWS7boSQz1mj3lJfb X-Google-Smtp-Source: AGHT+IFDTEJlxTlaQiAOqsKetI2wXncxQtVs9v69CWR7izlVYs1P7AgO0mxLpg+EsJ1yRk/Nc8Oydg== X-Received: by 2002:a05:6e02:17c9:b0:349:345b:6595 with SMTP id z9-20020a056e0217c900b00349345b6595mr611217ilu.11.1693429661168; Wed, 30 Aug 2023 14:07:41 -0700 (PDT) Received: from azeems-kspp.c.googlers.com.com (161.74.123.34.bc.googleusercontent.com. [34.123.74.161]) by smtp.gmail.com with ESMTPSA id ee16-20020a056638293000b0042b227eb1ddsm3958497jab.55.2023.08.30.14.07.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Aug 2023 14:07:40 -0700 (PDT) From: Azeem Shaikh To: "Martin K. Petersen" Cc: linux-hardening@vger.kernel.org, Azeem Shaikh , linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] scsi: target: Replace strlcpy with strscpy Date: Wed, 30 Aug 2023 21:07:24 +0000 Message-ID: <20230830210724.4156575-1-azeemshaikh38@gmail.com> X-Mailer: git-send-email 2.42.0.283.g2d96d420d3-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). Direct replacement is safe here since return value of -errno is used to check for truncation instead of sizeof(dest). [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Signed-off-by: Azeem Shaikh --- v2: * Replace all instances of strlcpy in this file instead of just 1. v1: * https://lore.kernel.org/all/20230830200717.4129442-1-azeemshaikh38@gmail.com/ drivers/target/target_core_configfs.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) -- 2.42.0.283.g2d96d420d3-goog diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c index 936e5ff1b209..10a22a428267 100644 --- a/drivers/target/target_core_configfs.c +++ b/drivers/target/target_core_configfs.c @@ -1392,16 +1392,15 @@ static ssize_t target_wwn_vendor_id_store(struct config_item *item, /* +2 to allow for a trailing (stripped) '\n' and null-terminator */ unsigned char buf[INQUIRY_VENDOR_LEN + 2]; char *stripped = NULL; - size_t len; + ssize_t len; ssize_t ret; - len = strlcpy(buf, page, sizeof(buf)); - if (len < sizeof(buf)) { + len = strscpy(buf, page, sizeof(buf)); + if (len > 0) { /* Strip any newline added from userspace. */ stripped = strstrip(buf); - len = strlen(stripped); } - if (len > INQUIRY_VENDOR_LEN) { + if (len < 0 || strlen(stripped) > INQUIRY_VENDOR_LEN) { pr_err("Emulated T10 Vendor Identification exceeds" " INQUIRY_VENDOR_LEN: " __stringify(INQUIRY_VENDOR_LEN) "\n"); @@ -1448,16 +1447,15 @@ static ssize_t target_wwn_product_id_store(struct config_item *item, /* +2 to allow for a trailing (stripped) '\n' and null-terminator */ unsigned char buf[INQUIRY_MODEL_LEN + 2]; char *stripped = NULL; - size_t len; + ssize_t len; ssize_t ret; - len = strlcpy(buf, page, sizeof(buf)); - if (len < sizeof(buf)) { + len = strscpy(buf, page, sizeof(buf)); + if (len > 0) { /* Strip any newline added from userspace. */ stripped = strstrip(buf); - len = strlen(stripped); } - if (len > INQUIRY_MODEL_LEN) { + if (len < 0 || strlen(stripped) > INQUIRY_MODEL_LEN) { pr_err("Emulated T10 Vendor exceeds INQUIRY_MODEL_LEN: " __stringify(INQUIRY_MODEL_LEN) "\n"); @@ -1504,16 +1502,15 @@ static ssize_t target_wwn_revision_store(struct config_item *item, /* +2 to allow for a trailing (stripped) '\n' and null-terminator */ unsigned char buf[INQUIRY_REVISION_LEN + 2]; char *stripped = NULL; - size_t len; + ssize_t len; ssize_t ret; - len = strlcpy(buf, page, sizeof(buf)); - if (len < sizeof(buf)) { + len = strscpy(buf, page, sizeof(buf)); + if (len > 0) { /* Strip any newline added from userspace. */ stripped = strstrip(buf); - len = strlen(stripped); } - if (len > INQUIRY_REVISION_LEN) { + if (len < 0 || strlen(stripped) > INQUIRY_REVISION_LEN) { pr_err("Emulated T10 Revision exceeds INQUIRY_REVISION_LEN: " __stringify(INQUIRY_REVISION_LEN) "\n");