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, 100 insertions, 0 deletions

diff --git a/scripts/atomic/gen-atomic-long.sh b/scripts/atomic/gen-atomic-long.sh
new file mode 100755
index 000000000..9826be3ba
--- /dev/null
+++ b/scripts/atomic/gen-atomic-long.sh
@@ -0,0 +1,100 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+ATOMICDIR=$(dirname $0)
+
+. ${ATOMICDIR}/atomic-tbl.sh
+
+#gen_cast(arg, int, atomic)
+gen_cast()
+{
+	local arg="$1"; shift
+	local int="$1"; shift
+	local atomic="$1"; shift
+
+	[ "${arg%%:*}" = "p" ] || return
+
+	printf "($(gen_param_type "${arg}" "${int}" "${atomic}"))"
+}
+
+#gen_args_cast(int, atomic, arg...)
+gen_args_cast()
+{
+	local int="$1"; shift
+	local atomic="$1"; shift
+
+	while [ "$#" -gt 0 ]; do
+		local cast="$(gen_cast "$1" "${int}" "${atomic}")"
+		local arg="$(gen_param_name "$1")"
+		printf "${cast}${arg}"
+		[ "$#" -gt 1 ] && printf ", "
+		shift;
+	done
+}
+
+#gen_proto_order_variant(meta, pfx, name, sfx, order, arg...)
+gen_proto_order_variant()
+{
+	local meta="$1"; shift
+	local pfx="$1"; shift
+	local name="$1"; shift
+	local sfx="$1"; shift
+	local order="$1"; shift
+
+	local atomicname="${pfx}${name}${sfx}${order}"
+
+	local ret="$(gen_ret_type "${meta}" "long")"
+	local params="$(gen_params "long" "atomic_long" "$@")"
+	local argscast_32="$(gen_args_cast "int" "atomic" "$@")"
+	local argscast_64="$(gen_args_cast "s64" "atomic64" "$@")"
+	local retstmt="$(gen_ret_stmt "${meta}")"
+
+	gen_kerneldoc "raw_" "${meta}" "${pfx}" "${name}" "${sfx}" "${order}" "atomic_long" "long" "$@"
+
+cat <<EOF
+static __always_inline ${ret}
+raw_atomic_long_${atomicname}(${params})
+{
+#ifdef CONFIG_64BIT
+	${retstmt}raw_atomic64_${atomicname}(${argscast_64});
+#else
+	${retstmt}raw_atomic_${atomicname}(${argscast_32});
+#endif
+}
+
+EOF
+}
+
+cat << EOF
+// SPDX-License-Identifier: GPL-2.0
+
+// Generated by $0
+// DO NOT MODIFY THIS FILE DIRECTLY
+
+#ifndef _LINUX_ATOMIC_LONG_H
+#define _LINUX_ATOMIC_LONG_H
+
+#include <linux/compiler.h>
+#include <asm/types.h>
+
+#ifdef CONFIG_64BIT
+typedef atomic64_t atomic_long_t;
+#define ATOMIC_LONG_INIT(i)		ATOMIC64_INIT(i)
+#define atomic_long_cond_read_acquire	atomic64_cond_read_acquire
+#define atomic_long_cond_read_relaxed	atomic64_cond_read_relaxed
+#else
+typedef atomic_t atomic_long_t;
+#define ATOMIC_LONG_INIT(i)		ATOMIC_INIT(i)
+#define atomic_long_cond_read_acquire	atomic_cond_read_acquire
+#define atomic_long_cond_read_relaxed	atomic_cond_read_relaxed
+#endif
+
+EOF
+
+grep '^[a-z]' "$1" | while read name meta args; do
+	gen_proto "${meta}" "${name}" ${args}
+done
+
+cat <<EOF
+#endif /* _LINUX_ATOMIC_LONG_H */
+EOF