From patchwork Mon Oct 23 18:32:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe JAILLET X-Patchwork-Id: 13433392 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 546B5219F1 for ; Mon, 23 Oct 2023 18:33:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=wanadoo.fr header.i=@wanadoo.fr header.b="emNSBpG/" Received: from out.smtpout.orange.fr (out-15.smtpout.orange.fr [193.252.22.15]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA4DD9B for ; Mon, 23 Oct 2023 11:33:05 -0700 (PDT) Received: from localhost.localdomain ([89.207.171.96]) by smtp.orange.fr with ESMTPSA id uzjXqFyhBlciauzjaqWBr8; Mon, 23 Oct 2023 20:33:03 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wanadoo.fr; s=t20230301; t=1698085983; bh=FMjgweLhTo5SkdcoVkpbQPkyPY7V0wNxVnhTVFmu8Uw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=emNSBpG/a9z3B1LDISJdjQaKSpJTUuKZpDTHiYtYZlavdx3+54rvcUgu0Cn2sHtnl 3FOcFQnp8G5lOpqX9RY0+ui+ci8ifYkIARA+gttPtI+ytelf1TlFTL80WgtS0+yRFe BAmDhOQYLMaQgpbMSW30h0IIfvUfSwQl1o3aEz/t5HqWgKGFN0G1nj+F03Prik93zi jXQ0MuoExuirfsSiR6of0Bk9z+685/GYw7SQfZM6cmnzFjt5VEKxkRk7kRUUHQRP6W sAntpAAf820X/JJyE8N0YeshMzhBqn5vqASJOvWRj679qL5D4SzO6V1RH4QTgrN9cT +VqLoqedq9CDw== X-ME-Helo: localhost.localdomain X-ME-Auth: Y2hyaXN0b3BoZS5qYWlsbGV0QHdhbmFkb28uZnI= X-ME-Date: Mon, 23 Oct 2023 20:33:03 +0200 X-ME-IP: 89.207.171.96 From: Christophe JAILLET To: rafael@kernel.org, lenb@kernel.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Christophe JAILLET Subject: [PATCH 1/4] ACPI: sysfs: Fix the check for a potential string truncation Date: Mon, 23 Oct 2023 20:32:54 +0200 Message-Id: <20001867d5d19c3b3e677f6020750cc232b3325b.1698081019.git.christophe.jaillet@wanadoo.fr> X-Mailer: git-send-email 2.32.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 snprintf() does not return negative values on error. To know if the buffer was too small, the returned value should be compared with the length of the passed buffer. If it is bigger or equal, then the output has been truncated. Update the test for truncation accordingly. Also return -ENOMEM in such a case, as already done below in the same functions. Fixes: 8765c5ba1949 ("ACPI / scan: Rework modalias creation when "compatible" is present") Signed-off-by: Christophe JAILLET --- drivers/acpi/device_sysfs.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c index 9d8e90744cb5..4deb36dccb73 100644 --- a/drivers/acpi/device_sysfs.c +++ b/drivers/acpi/device_sysfs.c @@ -158,8 +158,8 @@ static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalia return 0; len = snprintf(modalias, size, "acpi:"); - if (len <= 0) - return len; + if (len >= size) + return -ENOMEM; size -= len; @@ -212,8 +212,8 @@ static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); ACPI_FREE(buf.pointer); - if (len <= 0) - return len; + if (len >= size) + return -ENOMEM; of_compatible = acpi_dev->data.of_compatible; if (of_compatible->type == ACPI_TYPE_PACKAGE) {