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/arch/mips/bcm63xx/dev-rng.c b/arch/mips/bcm63xx/dev-rng.c
new file mode 100644
index 000000000..f94151f7c
--- /dev/null
+++ b/arch/mips/bcm63xx/dev-rng.c
@@ -0,0 +1,40 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2011 Florian Fainelli <florian@openwrt.org>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <bcm63xx_cpu.h>
+
+static struct resource rng_resources[] = {
+	{
+		.start		= -1, /* filled at runtime */
+		.end		= -1, /* filled at runtime */
+		.flags		= IORESOURCE_MEM,
+	},
+};
+
+static struct platform_device bcm63xx_rng_device = {
+	.name		= "bcm63xx-rng",
+	.id		= -1,
+	.num_resources	= ARRAY_SIZE(rng_resources),
+	.resource	= rng_resources,
+};
+
+static int __init bcm63xx_rng_register(void)
+{
+	if (!BCMCPU_IS_6368())
+		return -ENODEV;
+
+	rng_resources[0].start = bcm63xx_regset_address(RSET_RNG);
+	rng_resources[0].end = rng_resources[0].start;
+	rng_resources[0].end += RSET_RNG_SIZE - 1;
+
+	return platform_device_register(&bcm63xx_rng_device);
+}
+arch_initcall(bcm63xx_rng_register);