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/tools/net/ynl/Makefile b/tools/net/ynl/Makefile
new file mode 100644
index 000000000..3cefe4ed9
--- /dev/null
+++ b/tools/net/ynl/Makefile
@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: GPL-2.0
+
+include ../../scripts/Makefile.arch
+
+INSTALL	?= install
+prefix  ?= /usr
+ifeq ($(LP64), 1)
+  libdir_relative = lib64
+else
+  libdir_relative = lib
+endif
+libdir  ?= $(prefix)/$(libdir_relative)
+includedir ?= $(prefix)/include
+
+SPECDIR=../../../Documentation/netlink/specs
+
+SUBDIRS = lib generated ynltool tests
+
+all: $(SUBDIRS) libynl.a
+
+tests: | lib generated libynl.a
+ynltool: | lib generated libynl.a
+libynl.a: | lib generated
+	@echo -e "\tAR $@"
+	@$(AR) rcs $@ lib/ynl.o generated/*-user.o
+
+$(SUBDIRS):
+	@if [ -f "$@/Makefile" ] ; then \
+		$(MAKE) -C $@ ; \
+	fi
+
+clean distclean:
+	@for dir in $(SUBDIRS) ; do \
+		if [ -f "$$dir/Makefile" ] ; then \
+			$(MAKE) -C $$dir $@; \
+		fi \
+	done
+	rm -f libynl.a
+	rm -rf pyynl/__pycache__
+	rm -rf pyynl/lib/__pycache__
+	rm -rf pyynl.egg-info
+	rm -rf build
+
+install: libynl.a lib/*.h ynltool
+	@echo -e "\tINSTALL libynl.a"
+	@$(INSTALL) -d $(DESTDIR)$(libdir)
+	@$(INSTALL) -m 0644 libynl.a $(DESTDIR)$(libdir)/libynl.a
+	@echo -e "\tINSTALL libynl headers"
+	@$(INSTALL) -d $(DESTDIR)$(includedir)/ynl
+	@$(INSTALL) -m 0644 lib/*.h $(DESTDIR)$(includedir)/ynl/
+	@echo -e "\tINSTALL pyynl"
+	@pip install --prefix=$(DESTDIR)$(prefix) .
+	@make -C generated install
+	@make -C ynltool install
+
+run_tests:
+	@$(MAKE) -C tests run_tests
+
+lint:
+	yamllint $(SPECDIR)
+
+schema_check:
+	@N=1; \
+	for spec in $(SPECDIR)/*.yaml ; do \
+		NAME=$$(basename $$spec) ; \
+		OUTPUT=$$(./pyynl/cli.py --spec $$spec --validate) ; \
+		if [ $$? -eq 0 ] ; then \
+			echo "ok $$N $$NAME schema validation" ; \
+		else \
+			echo "not ok $$N $$NAME schema validation" ; \
+			echo "$$OUTPUT" ; \
+			echo ; \
+		fi ; \
+		N=$$((N+1)) ; \
+	done
+
+.PHONY: all clean distclean install run_tests lint schema_check $(SUBDIRS)