From patchwork Thu Feb 8 08:44:18 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lee Jones X-Patchwork-Id: 13549442 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7DC7371B4D; Thu, 8 Feb 2024 08:45:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707381933; cv=none; b=mBW3B3d6pI8fMVCqMGsEJ1yCBoWlnRRpAhNhmUckW6SKupjNUijJkYQxxs39wFTbEFdyitu/mLXzWpCxKKlsk7uwoXybugGl/0xrnX8Rb2jRCG2hcjfldQEREL4NdFwbK4iihNJ4WiFjD9c+gpicmKEgotfOD9xJ2VLKEtRJx5g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707381933; c=relaxed/simple; bh=PbzPd7ROc5va5PvBniGi9yT6iZxcViGR7FsGtUiYZPQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ax340BOOpImeQx4RMtE5KZ8gORbhvmtEyCceuXWAQwz3GV7QtcS30zAWS+bcRwBA5XxycrFrx15NGfQn+J5vBYHk+TDHnePeltwPi1rdUfYYr1ZqmmbiKz9P3eYhzaqEmtjPrdyiUiG2gb9k7RacFeGdEGDdUh2zy8MvBFhXLJw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JYv3wWWf; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JYv3wWWf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ECCBEC43394; Thu, 8 Feb 2024 08:45:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1707381932; bh=PbzPd7ROc5va5PvBniGi9yT6iZxcViGR7FsGtUiYZPQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JYv3wWWfitgg/S4wiWCNHUkrl6YEq7UHvBTMANfUjrWE6exn3/m3eE4TUhkWPXN+Y rRCC2FVaAkQZqV1mHCuFnaHh1E4JzU8l38xR/iT/qXy3v/vrN2OxQVG3lrZhMJjvCx o4T+oxyev2+cxar+vWyjTi6fPg7ODFt8JIJFQLVx0HGBORpVmo99miUmNAWAEXz00J mMdCOBIQwXoI84M6/sfhzlFbrNwoOdvX9cGpijg9bbVq5vEsPeuulOXxkJeOp03YD5 OMN6+cLmOLws/InUorErs1VlC3zfGGKrspeOEalGaY6iN4L2ycp8QkTyggjGOJ6JbQ S9VvuxHfX7/Ug== From: Lee Jones To: lee@kernel.org Cc: linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org Subject: [PATCH 06/10] scsi: aha1542: Replace snprintf() with the safer scnprintf() variant Date: Thu, 8 Feb 2024 08:44:18 +0000 Message-ID: <20240208084512.3803250-7-lee@kernel.org> X-Mailer: git-send-email 2.43.0.594.gd9cf4e227d-goog In-Reply-To: <20240208084512.3803250-1-lee@kernel.org> References: <20240208084512.3803250-1-lee@kernel.org> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 There is a general misunderstanding amongst engineers that {v}snprintf() returns the length of the data *actually* encoded into the destination array. However, as per the C99 standard {v}snprintf() really returns the length of the data that *would have been* written if there were enough space for it. This misunderstanding has led to buffer-overruns in the past. It's generally considered safer to use the {v}scnprintf() variants in their place (or even sprintf() in simple cases). So let's do that. Link: https://lwn.net/Articles/69419/ Link: https://github.com/KSPP/linux/issues/105 Signed-off-by: Lee Jones Reviewed-by: Kees Cook --- Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org --- drivers/scsi/aha1542.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/aha1542.c b/drivers/scsi/aha1542.c index 9503996c63256..b5ec7887801a5 100644 --- a/drivers/scsi/aha1542.c +++ b/drivers/scsi/aha1542.c @@ -772,7 +772,7 @@ static struct Scsi_Host *aha1542_hw_init(const struct scsi_host_template *tpnt, goto unregister; if (sh->dma_channel != 0xFF) - snprintf(dma_info, sizeof(dma_info), "DMA %d", sh->dma_channel); + scnprintf(dma_info, sizeof(dma_info), "DMA %d", sh->dma_channel); shost_printk(KERN_INFO, sh, "Adaptec AHA-1542 (SCSI-ID %d) at IO 0x%x, IRQ %d, %s\n", sh->this_id, base_io, sh->irq, dma_info); if (aha1542->bios_translation == BIOS_TRANSLATION_25563)