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, 77 insertions, 0 deletions

diff --git a/lib/xz/Kconfig b/lib/xz/Kconfig
new file mode 100644
index 000000000..20aa459bf
--- /dev/null
+++ b/lib/xz/Kconfig
@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config XZ_DEC
+	tristate "XZ decompression support"
+	select CRC32
+	help
+	  LZMA2 compression algorithm and BCJ filters are supported using
+	  the .xz file format as the container. For integrity checking,
+	  CRC32 is supported. See Documentation/staging/xz.rst for more
+	  information.
+
+if XZ_DEC
+
+config XZ_DEC_X86
+	bool "x86 BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_POWERPC
+	bool "PowerPC BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_ARM
+	bool "ARM BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_ARMTHUMB
+	bool "ARM-Thumb BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_ARM64
+	bool "ARM64 BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_SPARC
+	bool "SPARC BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_RISCV
+	bool "RISC-V BCJ filter decoder" if EXPERT
+	default y
+	select XZ_DEC_BCJ
+
+config XZ_DEC_MICROLZMA
+	bool "MicroLZMA decoder"
+	default n
+	help
+	  MicroLZMA is a header format variant where the first byte
+	  of a raw LZMA stream (without the end of stream marker) has
+	  been replaced with a bitwise-negation of the lc/lp/pb
+	  properties byte. MicroLZMA was created to be used in EROFS
+	  but can be used by other things too where wasting minimal
+	  amount of space for headers is important.
+
+	  Unless you know that you need this, say N.
+
+endif
+
+config XZ_DEC_BCJ
+	bool
+	default n
+
+config XZ_DEC_TEST
+	tristate "XZ decompressor tester"
+	default n
+	depends on XZ_DEC
+	help
+	  This allows passing .xz files to the in-kernel XZ decoder via
+	  a character special file. It calculates CRC32 of the decompressed
+	  data and writes diagnostics to the system log.
+
+	  Unless you are developing the XZ decoder, you don't need this
+	  and should say N.