From patchwork Thu Apr 11 16:46:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ivan Avdeev X-Patchwork-Id: 788225 Received: from mailtransmit04.runbox.com (mailtransmit04.runbox.com [185.226.149.37]) (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 6B3C417742; Thu, 11 Apr 2024 16:47:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.226.149.37 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712854032; cv=none; b=eCe7w8t7E7AIorwlqRDKSk9qAQXfzdMdStyDBsrZRrUoS12ofyeSCSIBlHlLzNN0ewE+AucVhVOZ65E/U+U0I+IjrY6UQlRsFC9XwTfgGKhm8DvjEjgjV9HQGxLrUkOHh2u+TCbeaQlCCv0o0kWi/kMVQF6iNBjUtTI92zFA4oY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712854032; c=relaxed/simple; bh=RyVOe6pCtx0/g7zEV7rXDdHduJWvub6mOy5PsGRPM7I=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=F19ALh1GPErHZEv2/sM1gzjxiGaJwgidBP760MyPmwd11340edpTzWwOqKntP6vhuujpvOfia4IaL2150ArNqPVsegYUTOqy+/U7sZZ6NUm6WgfkXzCdaZMhqNZNTkTvfthzXPEIF3RdIel66IK1v3Z3HfM60kzJ0wQvuFy3CfA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=provod.works; spf=pass smtp.mailfrom=provod.works; arc=none smtp.client-ip=185.226.149.37 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=provod.works Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=provod.works Received: from mailtransmit02.runbox ([10.9.9.162] helo=aibo.runbox.com) by mailtransmit04.runbox.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1ruxZs-002Jw4-5h; Thu, 11 Apr 2024 18:47:08 +0200 Received: from [10.9.9.73] (helo=submission02.runbox) by mailtransmit02.runbox with esmtp (Exim 4.86_2) (envelope-from ) id 1ruxZm-0004Du-KJ; Thu, 11 Apr 2024 18:47:02 +0200 Received: by submission02.runbox with esmtpsa [Authenticated ID (959450)] (TLS1.2:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.93) id 1ruxZl-00BPCo-2M; Thu, 11 Apr 2024 18:47:01 +0200 From: Ivan Avdeev To: laurent.pinchart@ideasonboard.com, dan.scally@ideasonboard.com, gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Ivan Avdeev Subject: [PATCH] usb: gadget: uvc: use correct buffer size when parsing configfs lists Date: Thu, 11 Apr 2024 12:46:16 -0400 Message-ID: <20240411164616.4130163-1-me@provod.works> X-Mailer: git-send-email 2.43.2 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This commit fixes uvc gadget support on 32-bit platforms. Commit 0df28607c5cb ("usb: gadget: uvc: Generalise helper functions for reuse") introduced a helper function __uvcg_iter_item_entries() to aid with parsing lists of items on configfs attributes stores. This function is a generalization of another very similar function, which used a stack-allocated temporary buffer of fixed size for each item in the list and used the sizeof() operator to check for potential buffer overruns. The new function was changed to allocate the now variably sized temp buffer on heap, but wasn't properly updated to also check for max buffer size using the computed size instead of sizeof() operator. As a result, the maximum item size was 7 (plus null terminator) on 64-bit platforms, and 3 on 32-bit ones. While 7 is accidentally just barely enough, 3 is definitely too small for some of UVC configfs attributes. For example, dwFrameInteval, specified in 100ns units, usually has 6-digit item values, e.g. 166666 for 60fps. Fixes: 0df28607c5cb ("usb: gadget: uvc: Generalise helper functions for reuse") Signed-off-by: Ivan Avdeev --- drivers/usb/gadget/function/uvc_configfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) base-commit: 2c71fdf02a95b3dd425b42f28fd47fb2b1d22702 diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c index 7e704b2bcfd1..a4377df612f5 100644 --- a/drivers/usb/gadget/function/uvc_configfs.c +++ b/drivers/usb/gadget/function/uvc_configfs.c @@ -92,10 +92,10 @@ static int __uvcg_iter_item_entries(const char *page, size_t len, while (pg - page < len) { i = 0; - while (i < sizeof(buf) && (pg - page < len) && + while (i < bufsize && (pg - page < len) && *pg != '\0' && *pg != '\n') buf[i++] = *pg++; - if (i == sizeof(buf)) { + if (i == bufsize) { ret = -EINVAL; goto out_free_buf; }