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, 23 insertions, 0 deletions

diff --git a/net/dcb/Kconfig b/net/dcb/Kconfig
new file mode 100644
index 000000000..efee8b9fe
--- /dev/null
+++ b/net/dcb/Kconfig
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config DCB
+	bool "Data Center Bridging support"
+	default n
+	help
+	  This enables support for configuring Data Center Bridging (DCB)
+	  features on DCB capable Ethernet adapters via rtnetlink.  Say 'Y'
+	  if you have a DCB capable Ethernet adapter which supports this
+	  interface and you are connected to a DCB capable switch.
+
+	  DCB is a collection of Ethernet enhancements which allow DCB capable
+	  NICs and switches to support network traffic with differing
+	  requirements (highly reliable, no drops vs. best effort vs. low
+	  latency) to co-exist on Ethernet.
+
+	  DCB features include:
+	    Enhanced Transmission Selection (aka Priority Grouping) - provides a
+	      framework for assigning bandwidth guarantees to traffic classes.
+	    Priority-based Flow Control (PFC) - a MAC control pause frame which
+	      works at the granularity of the 802.1p priority instead of the
+	      link (802.3x).
+
+	  If unsure, say N.