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, 110 insertions, 0 deletions

diff --git a/scripts/coccinelle/misc/warn.cocci b/scripts/coccinelle/misc/warn.cocci
new file mode 100644
index 000000000..b5f428035
--- /dev/null
+++ b/scripts/coccinelle/misc/warn.cocci
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/// Use WARN(1,...) rather than printk followed by WARN_ON(1)
+///
+// Confidence: High
+// Copyright: (C) 2012 Julia Lawall, INRIA/LIP6.
+// Copyright: (C) 2012 Gilles Muller, INRIA/LiP6.
+// URL: https://coccinelle.gitlabpages.inria.fr/website
+// Comments:
+// Options: --no-includes --include-headers
+
+virtual patch
+virtual context
+virtual org
+virtual report
+
+@bad1@
+position p;
+@@
+
+printk(...);
+printk@p(...);
+WARN_ON(1);
+
+@r1 depends on context || report || org@
+position p != bad1.p;
+@@
+
+ printk@p(...);
+*WARN_ON(1);
+
+@script:python depends on org@
+p << r1.p;
+@@
+
+cocci.print_main("printk + WARN_ON can be just WARN",p)
+
+@script:python depends on report@
+p << r1.p;
+@@
+
+msg = "SUGGESTION: printk + WARN_ON can be just WARN"
+coccilib.report.print_report(p[0],msg)
+
+@ok1 depends on patch@
+expression list es;
+position p != bad1.p;
+@@
+
+-printk@p(
++WARN(1,
+  es);
+-WARN_ON(1);
+
+@depends on patch@
+expression list ok1.es;
+@@
+
+if (...)
+- {
+  WARN(1,es);
+- }
+
+// --------------------------------------------------------------------
+
+@bad2@
+position p;
+@@
+
+printk(...);
+printk@p(...);
+WARN_ON_ONCE(1);
+
+@r2 depends on context || report || org@
+position p != bad1.p;
+@@
+
+ printk@p(...);
+*WARN_ON_ONCE(1);
+
+@script:python depends on org@
+p << r2.p;
+@@
+
+cocci.print_main("printk + WARN_ON_ONCE can be just WARN_ONCE",p)
+
+@script:python depends on report@
+p << r2.p;
+@@
+
+msg = "SUGGESTION: printk + WARN_ON_ONCE can be just WARN_ONCE"
+coccilib.report.print_report(p[0],msg)
+
+@ok2 depends on patch@
+expression list es;
+position p != bad2.p;
+@@
+
+-printk@p(
++WARN_ONCE(1,
+  es);
+-WARN_ON_ONCE(1);
+
+@depends on patch@
+expression list ok2.es;
+@@
+
+if (...)
+- {
+  WARN_ONCE(1,es);
+- }