From mboxrd@z Thu Jan 1 00:00:00 1970 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 2B24F227E88; Mon, 19 May 2025 21:22:18 +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=1747689738; cv=none; b=kZb/AKo4AAMzoJsaK5PtI3EJ36uP1Xt0DltWegK+H03wyzSGF1JdKFEj9xwna8fm7OLMRPGHlxg7TsxuPtlZwfWE2T2gubahEYhiFlnS0+joR6QFq3IjXkVWEQp0I89nPlt1wZ1FS4O8vRNm8cIJ/MgmfJc8WlrpX7oF0Vb352s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747689738; c=relaxed/simple; bh=Z+yB0flMSft2uwS0zLLzDtNhD6mSwuSDI2LoEPob+kM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fWKxbgShZ1FKp+WLs5kAmndwn4hJSkG/1vQX4N6puGF7EzWJRBDZujDe+Vxg1vgKwaGF2BQDbzlKcBS1dl5r7r/eZPr6mCpEWIO+k8aYyNs8YhADHWGm0CMNq7yXWeZkBqlFUH4nBJfFpcqud90MAYd+wgOqliNLWaYsNw0bIV8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=C5jaCsAM; 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="C5jaCsAM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E92B9C4CEF1; Mon, 19 May 2025 21:22:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747689738; bh=Z+yB0flMSft2uwS0zLLzDtNhD6mSwuSDI2LoEPob+kM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C5jaCsAMSnr5lf/Kw+KivshRo/9arYLUGL+SL7QZh7SEdxlsZFGAkzApW7bLoYWD3 s3btvPVoddAoMrYUOf+6JyLUksaiPRqgvCkVWZqmzzeIuDUU5JxapvrVd5qCpyO+Pt /2ib4eCk5AdlpiqvBOHNdByacoHo3xtUsHbmNz8Z+D3dvCN8NqfniC+eJY41WZDfqK 4FIaTKmC9VGPKoWsR+16T2vaNMYli2YTeXth2ZuYuQElm9Tcc5xqHC+vn5LNv6NhRf ygmPZ3J+YedqGd5czh6X0k9jroqw7AHf+NVFuLBHiNfbhkdlx3IkhWdLXxMTqQqNwe KNg1Ze8Kg6/hQ== From: Sasha Levin To: patches@lists.linux.dev, stable@vger.kernel.org Cc: Markus Burri , kernel test robot , Bartosz Golaszewski , Sasha Levin , linus.walleij@linaro.org, bgolaszewski@baylibre.com, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH AUTOSEL 6.12 06/18] gpio: virtuser: fix potential out-of-bound write Date: Mon, 19 May 2025 17:21:55 -0400 Message-Id: <20250519212208.1986028-6-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250519212208.1986028-1-sashal@kernel.org> References: <20250519212208.1986028-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.29 Content-Transfer-Encoding: 8bit From: Markus Burri [ Upstream commit 7118be7c6072f40391923543fdd1563b8d56377c ] If the caller wrote more characters, count is truncated to the max available space in "simple_write_to_buffer". Check that the input size does not exceed the buffer size. Write a zero termination afterwards. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202505091754.285hHbr2-lkp@intel.com/ Signed-off-by: Markus Burri Link: https://lore.kernel.org/r/20250509150459.115489-1-markus.burri@mt.com Signed-off-by: Bartosz Golaszewski Signed-off-by: Sasha Levin --- drivers/gpio/gpio-virtuser.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-virtuser.c b/drivers/gpio/gpio-virtuser.c index e89f299f21400..dcecb7a259117 100644 --- a/drivers/gpio/gpio-virtuser.c +++ b/drivers/gpio/gpio-virtuser.c @@ -400,10 +400,15 @@ static ssize_t gpio_virtuser_direction_do_write(struct file *file, char buf[32], *trimmed; int ret, dir, val = 0; - ret = simple_write_to_buffer(buf, sizeof(buf), ppos, user_buf, count); + if (count >= sizeof(buf)) + return -EINVAL; + + ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, user_buf, count); if (ret < 0) return ret; + buf[ret] = '\0'; + trimmed = strim(buf); if (strcmp(trimmed, "input") == 0) { @@ -622,12 +627,15 @@ static ssize_t gpio_virtuser_consumer_write(struct file *file, char buf[GPIO_VIRTUSER_NAME_BUF_LEN + 2]; int ret; + if (count >= sizeof(buf)) + return -EINVAL; + ret = simple_write_to_buffer(buf, GPIO_VIRTUSER_NAME_BUF_LEN, ppos, user_buf, count); if (ret < 0) return ret; - buf[strlen(buf) - 1] = '\0'; + buf[ret] = '\0'; ret = gpiod_set_consumer_name(data->ad.desc, buf); if (ret) -- 2.39.5