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 EF347220F55; Mon, 19 May 2025 21:21:45 +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=1747689706; cv=none; b=gZAb8CIfswJIbe207WHo9tGx/a/fBXGdYMYpLl7EIdMs21d3pEe1Itx5tLXsixwoGPoXBu5n/Ri47CMcaKmrISJ429DMvCC4tDpfnCYBPObCytWKlXCqTmv6bSFplGFlt3HwZJJazHGXjAea36PjrgdnN9pkSXH27vB8bud6i0c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747689706; c=relaxed/simple; bh=Z+yB0flMSft2uwS0zLLzDtNhD6mSwuSDI2LoEPob+kM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Xplg0/hmCp0anNCeX47YHy370/aBtObYsoMYNtBAHY7+1qwaJsO4TS4OOwV/QMlEjnM8evs2ZMgt8RUB8jipvQ++kR5LSmhfMOUs/leop7CLCkss80j5nDlaRR7dTnnJ1BWDNLCJaWH6cpvjYTjKRnSuuhy82f2wlTUn6Qpp7jk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kMuQ64Mw; 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="kMuQ64Mw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 577ACC4CEF4; Mon, 19 May 2025 21:21:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747689705; bh=Z+yB0flMSft2uwS0zLLzDtNhD6mSwuSDI2LoEPob+kM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kMuQ64MwuKAaw4wyu8lgpFgyubKJQW1Ul54ZsOsYbZphUNgwoVWZ2TijvOeB2wj9Q R9SzFOe1FVZxejJEqlB1K3Wnjxc8jqljI4viy+QCp+BjqSOodMVF7K9CDDcAjXWxeC Wl4wFtEIQEBiGct0gtL6veipoEE0iDKVmvEhhkcsmDUCivq7uBdoB26LAjndiGQWFB UY1ChzBlLOvBIeaNNt57YYquPkZBf7XGu9X2emGeURSmau0IQ4fy5chGiVHmaN26Wl TveeIt40GZzA6lqbC6wSUzuUn+2Eb5lwI58F4rV3JwV1ndOZQ+CKcEwRA90NjNfvm3 ZXKK4AI4Om2eg== 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 6.14 09/23] gpio: virtuser: fix potential out-of-bound write Date: Mon, 19 May 2025 17:21:16 -0400 Message-Id: <20250519212131.1985647-9-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250519212131.1985647-1-sashal@kernel.org> References: <20250519212131.1985647-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.14.7 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