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, 34 insertions, 0 deletions

diff --git a/tools/include/nolibc/std.h b/tools/include/nolibc/std.h
new file mode 100644
index 000000000..dc2dc46f8
--- /dev/null
+++ b/tools/include/nolibc/std.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * Standard definitions and types for NOLIBC
+ * Copyright (C) 2017-2021 Willy Tarreau <w@1wt.eu>
+ */
+
+#ifndef _NOLIBC_STD_H
+#define _NOLIBC_STD_H
+
+/* Declare a few quite common macros and types that usually are in stdlib.h,
+ * stdint.h, ctype.h, unistd.h and a few other common locations. Please place
+ * integer type definitions and generic macros here, but avoid OS-specific and
+ * syscall-specific stuff, as this file is expected to be included very early.
+ */
+
+#include "stdint.h"
+#include "stddef.h"
+
+#include <linux/types.h>
+
+/* those are commonly provided by sys/types.h */
+typedef uint64_t              dev_t;
+typedef uint64_t              ino_t;
+typedef unsigned int         mode_t;
+typedef   signed int          pid_t;
+typedef unsigned int          uid_t;
+typedef unsigned int          gid_t;
+typedef unsigned long       nlink_t;
+typedef  int64_t              off_t;
+typedef   signed long     blksize_t;
+typedef   signed long      blkcnt_t;
+typedef __kernel_time64_t    time_t;
+
+#endif /* _NOLIBC_STD_H */