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, 43 insertions, 0 deletions

diff --git a/drivers/char/Makefile b/drivers/char/Makefile
new file mode 100644
index 000000000..a46d7bf7c
--- /dev/null
+++ b/drivers/char/Makefile
@@ -0,0 +1,43 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the kernel character device drivers.
+#
+
+obj-y				+= mem.o random.o
+obj-$(CONFIG_TTY_PRINTK)	+= ttyprintk.o
+obj-y				+= misc.o
+obj-$(CONFIG_TEST_MISC_MINOR)	+= misc_minor_kunit.o
+obj-$(CONFIG_ATARI_DSP56K)	+= dsp56k.o
+obj-$(CONFIG_VIRTIO_CONSOLE)	+= virtio_console.o
+obj-$(CONFIG_UV_MMTIMER)	+= uv_mmtimer.o
+obj-$(CONFIG_IBM_BSR)		+= bsr.o
+
+obj-$(CONFIG_PRINTER)		+= lp.o
+
+obj-$(CONFIG_APM_EMULATION)	+= apm-emulation.o
+
+obj-$(CONFIG_SONYPI)		+= sonypi.o
+obj-$(CONFIG_HPET)		+= hpet.o
+obj-$(CONFIG_XILINX_HWICAP)	+= xilinx_hwicap/
+obj-$(CONFIG_NVRAM)		+= nvram.o
+obj-$(CONFIG_TOSHIBA)		+= toshiba.o
+obj-$(CONFIG_DS1620)		+= ds1620.o
+obj-$(CONFIG_HW_RANDOM)		+= hw_random/
+obj-$(CONFIG_PPDEV)		+= ppdev.o
+obj-$(CONFIG_NWBUTTON)		+= nwbutton.o
+obj-$(CONFIG_NWFLASH)		+= nwflash.o
+obj-$(CONFIG_SCx200_GPIO)	+= scx200_gpio.o
+obj-$(CONFIG_PC8736x_GPIO)	+= pc8736x_gpio.o
+obj-$(CONFIG_NSC_GPIO)		+= nsc_gpio.o
+obj-$(CONFIG_TELCLOCK)		+= tlclk.o
+
+obj-y				+= agp/
+
+obj-$(CONFIG_HANGCHECK_TIMER)	+= hangcheck-timer.o
+obj-$(CONFIG_TCG_TPM)		+= tpm/
+
+obj-$(CONFIG_PS3_FLASH)		+= ps3flash.o
+
+obj-$(CONFIG_XILLYBUS_CLASS)	+= xillybus/
+obj-$(CONFIG_POWERNV_OP_PANEL)	+= powernv-op-panel.o
+obj-$(CONFIG_ADI)		+= adi.o