From patchwork Tue Dec 12 21:25:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe JAILLET X-Patchwork-Id: 753378 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=wanadoo.fr header.i=@wanadoo.fr header.b="dOlEDMCf" Received: from smtp.smtpout.orange.fr (smtp-21.smtpout.orange.fr [80.12.242.21]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA6F0CD for ; Tue, 12 Dec 2023 13:25:23 -0800 (PST) Received: from pop-os.home ([92.140.202.140]) by smtp.orange.fr with ESMTPA id DAFkr5m2Q8sqPDAFkrjhwF; Tue, 12 Dec 2023 22:25:21 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wanadoo.fr; s=t20230301; t=1702416321; bh=xpWYbHV+Zc60bOBgrL8BoxkuvgOfsZpbRV1LTv1K99o=; h=From:To:Cc:Subject:Date; b=dOlEDMCfGy6oyhcN71SyY0UC1uniOSPcCj8dGJ3xvnA0SNrc23NXBqau4z3ZwJ1n+ NotE7DtXrPePRBNAKY+PCmSfSNX5yrMG9Y4rPERkwkKHJMeh3xUWXfxkmpXqknNwVQ x4BBduVuQGFZPk90tdSEhuhEEshkPO6rFNn1IflOfHHu9IPTjB/Z5qmv+aOr/oXvri 9Paxfew/tW9h6zxZP2MnD+3aTCgqd8dXvHHhCbISNY1y5tYB/3ibjodhl5GHZggrXi RTpLXvOgFV1RCjaqhmJhg0V01gfCZ08ZZsUOxsSfRobqf8WCSPqKZCGkLIKQ60xvNL AwZX3yrbUgTDQ== X-ME-Helo: pop-os.home X-ME-Auth: Y2hyaXN0b3BoZS5qYWlsbGV0QHdhbmFkb28uZnI= X-ME-Date: Tue, 12 Dec 2023 22:25:21 +0100 X-ME-IP: 92.140.202.140 From: Christophe JAILLET To: Hannes Reinecke , "James E.J. Bottomley" , "Martin K. Petersen" Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Christophe JAILLET , linux-scsi@vger.kernel.org Subject: [PATCH v2] scsi: myrb: Fix a potential string truncation in rebuild_show() and use sysfs_emit() Date: Tue, 12 Dec 2023 22:25:09 +0100 Message-Id: X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 "physical device - not rebuilding\n" is 34 bytes long. When written in 'buf' with a limit of 32 bytes, it is truncated. When building with W=1, it leads to: drivers/scsi/myrb.c: In function 'rebuild_show': drivers/scsi/myrb.c:1906:24: error: 'physical device - not rebuil...' directive output truncated writing 33 bytes into a region of size 32 [-Werror=format-truncation=] 1906 | return snprintf(buf, 32, "physical device - not rebuilding\n"); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/scsi/myrb.c:1906:24: note: 'snprintf' output 34 bytes into a destination of size 32 In order to fix it and to avoid hard-coded limits in all _show() functions, use the preferred sysfs_emit() that knows better about it. Signed-off-by: Christophe JAILLET --- Changes in v2: - Merge patch 1/2 and 2/2 v1: https://lore.kernel.org/all/cover.1702411083.git.christophe.jaillet@wanadoo.fr/ Note that there is another warning when building with W=1: 1051 | "%u.%02u-%c-%02u", | ^~~~~~~~~~~~~~~~~ drivers/scsi/myrb.c:1050:9: note: 'snprintf' output between 10 and 14 bytes into a destination of size 12 but I think that it is a false positive because snprintf() in Linux does not strickly folows the standard C behavior of sn --- drivers/scsi/myrb.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/drivers/scsi/myrb.c b/drivers/scsi/myrb.c index ca2380d2d6d3..06a5e6fb9f99 100644 --- a/drivers/scsi/myrb.c +++ b/drivers/scsi/myrb.c @@ -1767,7 +1767,7 @@ static ssize_t raid_state_show(struct device *dev, int ret; if (!sdev->hostdata) - return snprintf(buf, 16, "Unknown\n"); + return sysfs_emit(buf, "Unknown\n"); if (sdev->channel == myrb_logical_channel(sdev->host)) { struct myrb_ldev_info *ldev_info = sdev->hostdata; @@ -1775,10 +1775,10 @@ static ssize_t raid_state_show(struct device *dev, name = myrb_devstate_name(ldev_info->state); if (name) - ret = snprintf(buf, 32, "%s\n", name); + ret = sysfs_emit(buf, "%s\n", name); else - ret = snprintf(buf, 32, "Invalid (%02X)\n", - ldev_info->state); + ret = sysfs_emit(buf, "Invalid (%02X)\n", + ldev_info->state); } else { struct myrb_pdev_state *pdev_info = sdev->hostdata; unsigned short status; @@ -1796,10 +1796,10 @@ static ssize_t raid_state_show(struct device *dev, else name = myrb_devstate_name(pdev_info->state); if (name) - ret = snprintf(buf, 32, "%s\n", name); + ret = sysfs_emit(buf, "%s\n", name); else - ret = snprintf(buf, 32, "Invalid (%02X)\n", - pdev_info->state); + ret = sysfs_emit(buf, "Invalid (%02X)\n", + pdev_info->state); } return ret; } @@ -1886,11 +1886,11 @@ static ssize_t raid_level_show(struct device *dev, name = myrb_raidlevel_name(ldev_info->raid_level); if (!name) - return snprintf(buf, 32, "Invalid (%02X)\n", - ldev_info->state); - return snprintf(buf, 32, "%s\n", name); + return sysfs_emit(buf, "Invalid (%02X)\n", + ldev_info->state); + return sysfs_emit(buf, "%s\n", name); } - return snprintf(buf, 32, "Physical Drive\n"); + return sysfs_emit(buf, "Physical Drive\n"); } static DEVICE_ATTR_RO(raid_level); @@ -1903,17 +1903,17 @@ static ssize_t rebuild_show(struct device *dev, unsigned char status; if (sdev->channel < myrb_logical_channel(sdev->host)) - return snprintf(buf, 32, "physical device - not rebuilding\n"); + return sysfs_emit(buf, "physical device - not rebuilding\n"); status = myrb_get_rbld_progress(cb, &rbld_buf); if (rbld_buf.ldev_num != sdev->id || status != MYRB_STATUS_SUCCESS) - return snprintf(buf, 32, "not rebuilding\n"); + return sysfs_emit(buf, "not rebuilding\n"); - return snprintf(buf, 32, "rebuilding block %u of %u\n", - rbld_buf.ldev_size - rbld_buf.blocks_left, - rbld_buf.ldev_size); + return sysfs_emit(buf, "rebuilding block %u of %u\n", + rbld_buf.ldev_size - rbld_buf.blocks_left, + rbld_buf.ldev_size); } static ssize_t rebuild_store(struct device *dev, @@ -2140,7 +2140,7 @@ static ssize_t ctlr_num_show(struct device *dev, struct Scsi_Host *shost = class_to_shost(dev); struct myrb_hba *cb = shost_priv(shost); - return snprintf(buf, 20, "%u\n", cb->ctlr_num); + return sysfs_emit(buf, "%u\n", cb->ctlr_num); } static DEVICE_ATTR_RO(ctlr_num); @@ -2150,7 +2150,7 @@ static ssize_t firmware_show(struct device *dev, struct Scsi_Host *shost = class_to_shost(dev); struct myrb_hba *cb = shost_priv(shost); - return snprintf(buf, 16, "%s\n", cb->fw_version); + return sysfs_emit(buf, "%s\n", cb->fw_version); } static DEVICE_ATTR_RO(firmware); @@ -2160,7 +2160,7 @@ static ssize_t model_show(struct device *dev, struct Scsi_Host *shost = class_to_shost(dev); struct myrb_hba *cb = shost_priv(shost); - return snprintf(buf, 16, "%s\n", cb->model_name); + return sysfs_emit(buf, "%s\n", cb->model_name); } static DEVICE_ATTR_RO(model);