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, 178 insertions, 0 deletions

diff --git a/drivers/of/of_test.c b/drivers/of/of_test.c
new file mode 100644
index 000000000..8bba5a72c
--- /dev/null
+++ b/drivers/of/of_test.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit tests for OF APIs
+ */
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <kunit/test.h>
+
+#include "of_private.h"
+
+/*
+ * Test that the root node "/" can be found by path.
+ */
+static void of_dtb_root_node_found_by_path(struct kunit *test)
+{
+	struct device_node *np;
+
+	np = of_find_node_by_path("/");
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, np);
+	of_node_put(np);
+}
+
+/*
+ * Test that the 'of_root' global variable is always populated when DT code is
+ * enabled. Remove this test once of_root is removed from global access.
+ */
+static void of_dtb_root_node_populates_of_root(struct kunit *test)
+{
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, of_root);
+}
+
+static struct kunit_case of_dtb_test_cases[] = {
+	KUNIT_CASE(of_dtb_root_node_found_by_path),
+	KUNIT_CASE(of_dtb_root_node_populates_of_root),
+	{}
+};
+
+static int of_dtb_test_init(struct kunit *test)
+{
+	of_root_kunit_skip(test);
+	if (!IS_ENABLED(CONFIG_OF_EARLY_FLATTREE))
+		kunit_skip(test, "requires CONFIG_OF_EARLY_FLATTREE");
+
+	return 0;
+}
+
+/*
+ * Test suite to confirm a DTB is loaded.
+ */
+static struct kunit_suite of_dtb_suite = {
+	.name = "of_dtb",
+	.test_cases = of_dtb_test_cases,
+	.init = of_dtb_test_init,
+};
+
+struct of_address_resource_bounds_case {
+	u64 start;
+	u64 size;
+	int ret;
+
+	u64 res_start;
+	u64 res_end;
+};
+
+static void of_address_resource_bounds_case_desc(const struct of_address_resource_bounds_case *p,
+						 char *name)
+{
+	snprintf(name, KUNIT_PARAM_DESC_SIZE, "start=0x%016llx,size=0x%016llx", p->start, p->size);
+}
+
+static const struct of_address_resource_bounds_case of_address_resource_bounds_cases[] = {
+	{
+		.start = 0,
+		.size = 0,
+		.ret = 0,
+		.res_start = 0,
+		.res_end = -1,
+	},
+	{
+		.start = 0,
+		.size = 0x1000,
+		.ret = 0,
+		.res_start = 0,
+		.res_end = 0xfff,
+	},
+	{
+		.start = 0x1000,
+		.size = 0,
+		.ret = 0,
+		.res_start = 0x1000,
+		.res_end = 0xfff,
+	},
+	{
+		.start = 0x1000,
+		.size = 0x1000,
+		.ret = 0,
+		.res_start = 0x1000,
+		.res_end = 0x1fff,
+	},
+	{
+		.start = 1,
+		.size = RESOURCE_SIZE_MAX,
+		.ret = 0,
+		.res_start = 1,
+		.res_end = RESOURCE_SIZE_MAX,
+	},
+	{
+		.start = RESOURCE_SIZE_MAX,
+		.size = 1,
+		.ret = 0,
+		.res_start = RESOURCE_SIZE_MAX,
+		.res_end = RESOURCE_SIZE_MAX,
+	},
+	{
+		.start = 2,
+		.size = RESOURCE_SIZE_MAX,
+		.ret = -EOVERFLOW,
+	},
+	{
+		.start = RESOURCE_SIZE_MAX,
+		.size = 2,
+		.ret = -EOVERFLOW,
+	},
+	{
+		.start = ULL(0x100000000),
+		.size = 1,
+		.ret = sizeof(resource_size_t) > sizeof(u32) ? 0 : -EOVERFLOW,
+		.res_start = ULL(0x100000000),
+		.res_end = ULL(0x100000000),
+	},
+	{
+		.start = 0x1000,
+		.size = 0xffffffff,
+		.ret = sizeof(resource_size_t) > sizeof(u32) ? 0 : -EOVERFLOW,
+		.res_start = 0x1000,
+		.res_end = ULL(0x100000ffe),
+	},
+};
+
+KUNIT_ARRAY_PARAM(of_address_resource_bounds,
+		  of_address_resource_bounds_cases, of_address_resource_bounds_case_desc);
+
+static void of_address_resource_bounds(struct kunit *test)
+{
+	const struct of_address_resource_bounds_case *param = test->param_value;
+	struct resource r; /* Intentionally uninitialized */
+	int ret;
+
+	if (!IS_ENABLED(CONFIG_OF_ADDRESS))
+		kunit_skip(test, "CONFIG_OF_ADDRESS not enabled\n");
+
+	ret = __of_address_resource_bounds(&r, param->start, param->size);
+	KUNIT_EXPECT_EQ(test, param->ret, ret);
+	if (ret == 0) {
+		KUNIT_EXPECT_EQ(test, (resource_size_t)param->res_start, r.start);
+		KUNIT_EXPECT_EQ(test, (resource_size_t)param->res_end, r.end);
+		KUNIT_EXPECT_EQ(test, param->size, resource_size(&r));
+	}
+}
+
+static struct kunit_case of_address_test_cases[] = {
+	KUNIT_CASE_PARAM(of_address_resource_bounds, of_address_resource_bounds_gen_params),
+	{}
+};
+
+static struct kunit_suite of_address_suite = {
+	.name = "of_address",
+	.test_cases = of_address_test_cases,
+};
+
+kunit_test_suites(
+	&of_dtb_suite, &of_address_suite,
+);
+MODULE_DESCRIPTION("KUnit tests for OF APIs");
+MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
+MODULE_LICENSE("GPL");