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, 81 insertions, 0 deletions

diff --git a/Documentation/driver-api/backlight/lp855x-driver.rst b/Documentation/driver-api/backlight/lp855x-driver.rst
new file mode 100644
index 000000000..1e0b224fc
--- /dev/null
+++ b/Documentation/driver-api/backlight/lp855x-driver.rst
@@ -0,0 +1,81 @@
+====================
+Kernel driver lp855x
+====================
+
+Backlight driver for LP855x ICs
+
+Supported chips:
+
+	Texas Instruments LP8550, LP8551, LP8552, LP8553, LP8555, LP8556 and
+	LP8557
+
+Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+
+Description
+-----------
+
+* Brightness control
+
+  Brightness can be controlled by the pwm input or the i2c command.
+  The lp855x driver supports both cases.
+
+* Device attributes
+
+  1) bl_ctl_mode
+
+  Backlight control mode.
+
+  Value: pwm based or register based
+
+  2) chip_id
+
+  The lp855x chip id.
+
+  Value: lp8550/lp8551/lp8552/lp8553/lp8555/lp8556/lp8557
+
+Platform data for lp855x
+------------------------
+
+For supporting platform specific data, the lp855x platform data can be used.
+
+* name:
+	Backlight driver name. If it is not defined, default name is set.
+* device_control:
+	Value of DEVICE CONTROL register.
+* initial_brightness:
+	Initial value of backlight brightness.
+* period_ns:
+	Platform specific PWM period value. unit is nano.
+	Only valid when brightness is pwm input mode.
+* size_program:
+	Total size of lp855x_rom_data.
+* rom_data:
+	List of new eeprom/eprom registers.
+
+Examples
+========
+
+1) lp8552 platform data: i2c register mode with new eeprom data::
+
+    #define EEPROM_A5_ADDR	0xA5
+    #define EEPROM_A5_VAL	0x4f	/* EN_VSYNC=0 */
+
+    static struct lp855x_rom_data lp8552_eeprom_arr[] = {
+	{EEPROM_A5_ADDR, EEPROM_A5_VAL},
+    };
+
+    static struct lp855x_platform_data lp8552_pdata = {
+	.name = "lcd-bl",
+	.device_control = I2C_CONFIG(LP8552),
+	.initial_brightness = INITIAL_BRT,
+	.size_program = ARRAY_SIZE(lp8552_eeprom_arr),
+	.rom_data = lp8552_eeprom_arr,
+    };
+
+2) lp8556 platform data: pwm input mode with default rom data::
+
+    static struct lp855x_platform_data lp8556_pdata = {
+	.device_control = PWM_CONFIG(LP8556),
+	.initial_brightness = INITIAL_BRT,
+	.period_ns = 1000000,
+    };