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, 40 insertions, 0 deletions

diff --git a/rust/helpers/time.c b/rust/helpers/time.c
new file mode 100644
index 000000000..32f495970
--- /dev/null
+++ b/rust/helpers/time.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/delay.h>
+#include <linux/ktime.h>
+#include <linux/timekeeping.h>
+
+__rust_helper void rust_helper_fsleep(unsigned long usecs)
+{
+	fsleep(usecs);
+}
+
+__rust_helper ktime_t rust_helper_ktime_get_real(void)
+{
+	return ktime_get_real();
+}
+
+__rust_helper ktime_t rust_helper_ktime_get_boottime(void)
+{
+	return ktime_get_boottime();
+}
+
+__rust_helper ktime_t rust_helper_ktime_get_clocktai(void)
+{
+	return ktime_get_clocktai();
+}
+
+__rust_helper s64 rust_helper_ktime_to_us(const ktime_t kt)
+{
+	return ktime_to_us(kt);
+}
+
+__rust_helper s64 rust_helper_ktime_to_ms(const ktime_t kt)
+{
+	return ktime_to_ms(kt);
+}
+
+__rust_helper void rust_helper_udelay(unsigned long usec)
+{
+	udelay(usec);
+}