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>

1 files changed, 62 insertions, 0 deletions

diff --git a/Documentation/trace/sys-t.rst b/Documentation/trace/sys-t.rst
new file mode 100644
index 000000000..3d8eb9273
--- /dev/null
+++ b/Documentation/trace/sys-t.rst
@@ -0,0 +1,62 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================
+MIPI SyS-T over STP
+===================
+
+The MIPI SyS-T protocol driver can be used with STM class devices to
+generate standardized trace stream. Aside from being a standard, it
+provides better trace source identification and timestamp correlation.
+
+In order to use the MIPI SyS-T protocol driver with your STM device,
+first, you'll need CONFIG_STM_PROTO_SYS_T.
+
+Now, you can select which protocol driver you want to use when you create
+a policy for your STM device, by specifying it in the policy name:
+
+# mkdir /config/stp-policy/dummy_stm.0:p_sys-t.my-policy/
+
+In other words, the policy name format is extended like this:
+
+  <device_name>:<protocol_name>.<policy_name>
+
+With Intel TH, therefore it can look like "0-sth:p_sys-t.my-policy".
+
+If the protocol name is omitted, the STM class will chose whichever
+protocol driver was loaded first.
+
+You can also double check that everything is working as expected by
+
+# cat /config/stp-policy/dummy_stm.0:p_sys-t.my-policy/protocol
+p_sys-t
+
+Now, with the MIPI SyS-T protocol driver, each policy node in the
+configfs gets a few additional attributes, which determine per-source
+parameters specific to the protocol:
+
+# mkdir /config/stp-policy/dummy_stm.0:p_sys-t.my-policy/default
+# ls /config/stp-policy/dummy_stm.0:p_sys-t.my-policy/default
+channels
+clocksync_interval
+do_len
+masters
+ts_interval
+uuid
+
+The most important one here is the "uuid", which determines the UUID
+that will be used to tag all data coming from this source. It is
+automatically generated when a new node is created, but it is likely
+that you would want to change it.
+
+do_len switches on/off the additional "payload length" field in the
+MIPI SyS-T message header. It is off by default as the STP already
+marks message boundaries.
+
+ts_interval and clocksync_interval determine how much time in milliseconds
+can pass before we need to include a protocol (not transport, aka STP)
+timestamp in a message header or send a CLOCKSYNC packet, respectively.
+
+See Documentation/ABI/testing/configfs-stp-policy-p_sys-t for more
+details.
+
+* [1] https://www.mipi.org/specifications/sys-t