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, 55 insertions, 0 deletions

diff --git a/tools/testing/memblock/Makefile b/tools/testing/memblock/Makefile
new file mode 100644
index 000000000..d80982ccd
--- /dev/null
+++ b/tools/testing/memblock/Makefile
@@ -0,0 +1,55 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# Memblock simulator requires AddressSanitizer (libasan) and liburcu development
+# packages installed
+CFLAGS += -I. -I../../include -Wall -O2 -fsanitize=address \
+	  -fsanitize=undefined -D CONFIG_PHYS_ADDR_T_64BIT
+LDFLAGS += -fsanitize=address -fsanitize=undefined
+TARGETS = main
+TEST_OFILES = tests/alloc_nid_api.o tests/alloc_helpers_api.o tests/alloc_api.o \
+		  tests/basic_api.o tests/common.o tests/alloc_exact_nid_api.o
+DEP_OFILES = memblock.o lib/slab.o mmzone.o slab.o cmdline.o
+OFILES = main.o $(DEP_OFILES) $(TEST_OFILES)
+EXTR_SRC = ../../../mm/memblock.c
+
+ifeq ($(BUILD), 32)
+	CFLAGS += -m32
+	LDFLAGS += -m32
+endif
+
+# Process user parameters
+include scripts/Makefile.include
+
+main: $(OFILES)
+
+$(OFILES): include
+
+include: ../../../include/linux/memblock.h ../../include/linux/*.h \
+	../../include/asm/*.h
+
+	@mkdir -p linux
+	test -L linux/memblock.h || ln -s ../../../../include/linux/memblock.h linux/memblock.h
+	test -L asm/asm.h || ln -s ../../../arch/x86/include/asm/asm.h asm/asm.h
+	test -L asm/cmpxchg.h || ln -s ../../../arch/x86/include/asm/cmpxchg.h asm/cmpxchg.h
+
+memblock.c: $(EXTR_SRC)
+	test -L memblock.c || ln -s $(EXTR_SRC) memblock.c
+
+clean:
+	$(RM) $(TARGETS) $(OFILES) linux/memblock.h memblock.c asm/asm.h asm/cmpxchg.h
+
+help:
+	@echo  'Memblock simulator'
+	@echo  ''
+	@echo  'Available targets:'
+	@echo  '  main		  - Build the memblock simulator'
+	@echo  '  clean		  - Remove generated files and symlinks in the directory'
+	@echo  ''
+	@echo  'Configuration:'
+	@echo  '  make MEMBLOCK_DEBUG=1     - enable memblock_dbg() messages'
+	@echo  '  make NUMA=1               - simulate enabled NUMA'
+	@echo  '  make 32BIT_PHYS_ADDR_T=1  - Use 32 bit physical addresses'
+
+vpath %.c ../../lib
+
+.PHONY: clean include help