diff options
| author | Muhammad Bilal <meatuni001@gmail.com> | 2026-07-28 17:54:55 +0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-09-01 12:15:16 +0200 |
| commit | ff917923f4fb9c83717ba135ee47d7e4c1567bb7 (patch) | |
| tree | c38fd8fcf58e1937b17fdbc6518b6f8b797fc15a /Documentation/admin-guide/media/vimc.rst | |
| download | linux-stable-ff917923f4fb9c83717ba135ee47d7e4c1567bb7.tar.gz linux-stable-ff917923f4fb9c83717ba135ee47d7e4c1567bb7.zip | |
staging: rtl8723bs: fix OOB read in rtw_action_frame_parse()grafted
rtw_action_frame_parse() takes a frame_len parameter but never
actually checks it before indexing into the frame body:
const u8 *frame_body = frame + sizeof(struct ieee80211_hdr_3addr);
...
c = frame_body[0];
...
a = frame_body[1];
frame_body already points 24 bytes (sizeof(struct
ieee80211_hdr_3addr)) into frame, so reading frame_body[0] and
frame_body[1] requires frame_len >= 26. A management action frame
shorter than that (e.g. exactly 24 bytes, the minimum a malicious
peer can send) causes a 1-2 byte out-of-bounds read.
This is reachable from rtw_cfg80211_monitor_if_xmit_entry() and
cfg80211_rtw_mgmt_tx() in ioctl_cfg80211.c, both of which pass
attacker/user-influenced frame buffers and lengths straight through.
Add the missing length check before frame_body is dereferenced.
Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/admin-guide/media/vimc.rst')
| -rw-r--r-- | Documentation/admin-guide/media/vimc.rst | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/Documentation/admin-guide/media/vimc.rst b/Documentation/admin-guide/media/vimc.rst new file mode 100644 index 000000000..29d843a8d --- /dev/null +++ b/Documentation/admin-guide/media/vimc.rst @@ -0,0 +1,110 @@ +.. SPDX-License-Identifier: GPL-2.0 + +The Virtual Media Controller Driver (vimc) +========================================== + +The vimc driver emulates complex video hardware using the V4L2 API and the Media +API. It has a capture device and three subdevices: sensor, debayer and scaler. + +Topology +-------- + +The topology is hardcoded, although you could modify it in vimc-core and +recompile the driver to achieve your own topology. This is the default topology: + +.. _vimc_topology_graph: + +.. kernel-figure:: vimc.dot + :alt: Diagram of the default media pipeline topology + :align: center + + Media pipeline graph on vimc + +Configuring the topology +~~~~~~~~~~~~~~~~~~~~~~~~ + +Each subdevice will come with its default configuration (pixelformat, height, +width, ...). One needs to configure the topology in order to match the +configuration on each linked subdevice to stream frames through the pipeline. +If the configuration doesn't match, the stream will fail. The ``v4l-utils`` +package is a bundle of user-space applications, that comes with ``media-ctl`` and +``v4l2-ctl`` that can be used to configure the vimc configuration. This sequence +of commands fits for the default topology: + +.. code-block:: bash + + media-ctl -d platform:vimc -V '"Sensor A":0[fmt:SBGGR8_1X8/640x480]' + media-ctl -d platform:vimc -V '"Debayer A":0[fmt:SBGGR8_1X8/640x480]' + media-ctl -d platform:vimc -V '"Scaler":0[fmt:RGB888_1X24/640x480]' + media-ctl -d platform:vimc -V '"Scaler":0[crop:(100,50)/400x150]' + media-ctl -d platform:vimc -V '"Scaler":1[fmt:RGB888_1X24/300x700]' + v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v width=300,height=700 + v4l2-ctl -z platform:vimc -d "Raw Capture 0" -v pixelformat=BA81 + +Subdevices +---------- + +Subdevices define the behavior of an entity in the topology. Depending on the +subdevice, the entity can have multiple pads of type source or sink. + +vimc-sensor: + Generates images in several formats using video test pattern generator. + Exposes: + + * 1 Pad source + +vimc-lens: + Ancillary lens for a sensor. Supports auto focus control. Linked to + a vimc-sensor using an ancillary link. The lens supports FOCUS_ABSOLUTE + control. + +.. code-block:: bash + + media-ctl -p + ... + - entity 28: Lens A (0 pad, 0 link) + type V4L2 subdev subtype Lens flags 0 + device node name /dev/v4l-subdev6 + - entity 29: Lens B (0 pad, 0 link) + type V4L2 subdev subtype Lens flags 0 + device node name /dev/v4l-subdev7 + v4l2-ctl -d /dev/v4l-subdev7 -C focus_absolute + focus_absolute: 0 + + +vimc-debayer: + Transforms images in bayer format into a non-bayer format. + Exposes: + + * 1 Pad sink + * 1 Pad source + +vimc-scaler: + Re-size the image to meet the source pad resolution. E.g.: if the sync + pad is configured to 360x480 and the source to 1280x720, the image will + be stretched to fit the source resolution. Works for any resolution + within the vimc limitations (even shrinking the image if necessary). + Exposes: + + * 1 Pad sink + * 1 Pad source + +vimc-capture: + Exposes node /dev/videoX to allow userspace to capture the stream. + Exposes: + + * 1 Pad sink + * 1 Pad source + +Module options +-------------- + +Vimc has a module parameter to configure the driver. + +* ``allocator=<unsigned int>`` + + memory allocator selection, default is 0. It specifies the way buffers + will be allocated. + + - 0: vmalloc + - 1: dma-contig |
