From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 88626442B12; Mon, 17 Aug 2026 15:09:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786979399; cv=none; b=rApr3KHig1jSSrtO1wkI29NjM47+/8+6x2lWvkH/mTb7LXkhrl2AOZZrgzIq2Imq/iAYXFUTC87GuDQnXtmfKS1AwZBWda1aS7WVyy2kr3zg7QgvQcc5bJ9pl5MPnXmxN/2RRIYP23roAcNCdzYCw5uaBdtjXiXCAoy8iVqzpIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786979399; c=relaxed/simple; bh=5ofmXZRpGKO+DxyZ9RJLxpNrHO2mSeYSRRRQt6dVcng=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NUI4YZL1YP4XE30Nm27jJRd1ovzPI4coK+7n22xO6SuUAKaeXMH8pqwK584+xnwXyAbkWBpA/pbUKBEpb2KawaSMomfjeUeEobizPbWb3bw8Auslusu6b/XschjtMeChw9pRnE+xhql16qaknC57DJE186vkSapQKBl9kmsFaLo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=IUjHLKmO; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="IUjHLKmO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9AD861F000E9; Mon, 17 Aug 2026 15:09:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786979398; bh=au1ePHEIHsEpYybGY+EvRUwPwZEzLXH6iq8aYk4zzls=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=IUjHLKmO/RVM/mYF+sRW14fjlUwqDlyPQADQWfQ5lmHphj91rdeXu7jXoJST6LwRw UvH+sJ/Qu7Dd9IY/iQggn4OkySfzBKoAnoj980XHOWNz67SEGJi4kMyl13kbnxclYW Vupj3kHYoY2BUB0e1SsiMt0TtQzv52A3MI/dZKVY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zile Xiong , Marek Szyprowski , Hans Verkuil Subject: [PATCH 6.1 212/609] media: vb2: use ssize_t for vb2_read/vb2_write Date: Mon, 17 Aug 2026 15:28:28 +0200 Message-ID: <20260817132551.184253422@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132543.039278408@linuxfoundation.org> References: <20260817132543.039278408@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zile Xiong commit a562d6dc86bdfdd299e1b4734977a8d63e803583 upstream. vb2_read() and vb2_write() return size_t, but propagate negative errno values from __vb2_perform_fileio(). This relies on implicit signed/unsigned conversions in callers (e.g. vb2_fop_read()) to recover error codes: __vb2_perform_fileio() -> -EINVAL vb2_read() -> (size_t)-EINVAL vb2_fop_read() -> -EINVAL This relies on implicit conversions that are not obvious. These helpers are exported (EXPORT_SYMBOL_GPL) and part of the vb2 API, so changing their return type may affect existing users. However, they conceptually follow read/write semantics, where ssize_t is typically used to return either a byte count or a negative error code. Switch vb2_read() and vb2_write() to ssize_t, and update __vb2_perform_fileio() accordingly. Signed-off-by: Zile Xiong Acked-by: Marek Szyprowski Fixes: b25748fe6126 ("[media] v4l: videobuf2: add read() and write() emulator") Cc: stable@vger.kernel.org Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman --- drivers/media/common/videobuf2/videobuf2-core.c | 12 ++++++------ include/media/videobuf2-core.h | 8 ++++---- 2 files changed, 10 insertions(+), 10 deletions(-) --- a/drivers/media/common/videobuf2/videobuf2-core.c +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -2770,8 +2770,8 @@ static int __vb2_cleanup_fileio(struct v * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) * @read: access mode selector (1 means read, 0 means write) */ -static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, - loff_t *ppos, int nonblock, int read) +static ssize_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblock, int read) { struct vb2_fileio_data *fileio; struct vb2_fileio_buf *buf; @@ -2931,15 +2931,15 @@ static size_t __vb2_perform_fileio(struc return ret; } -size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, - loff_t *ppos, int nonblocking) +ssize_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblocking) { return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1); } EXPORT_SYMBOL_GPL(vb2_read); -size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, - loff_t *ppos, int nonblocking) +ssize_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, + loff_t *ppos, int nonblocking) { return __vb2_perform_fileio(q, (char __user *) data, count, ppos, nonblocking, 0); --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -1050,8 +1050,8 @@ __poll_t vb2_core_poll(struct vb2_queue * @ppos: file handle position tracking pointer * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) */ -size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, - loff_t *ppos, int nonblock); +ssize_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblock); /** * vb2_write() - implements write() syscall logic. * @q: pointer to &struct vb2_queue with videobuf2 queue. @@ -1060,8 +1060,8 @@ size_t vb2_read(struct vb2_queue *q, cha * @ppos: file handle position tracking pointer * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) */ -size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, - loff_t *ppos, int nonblock); +ssize_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, + loff_t *ppos, int nonblock); /** * typedef vb2_thread_fnc - callback function for use with vb2_thread.