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, 45 insertions, 0 deletions

diff --git a/scripts/Makefile.vdsoinst b/scripts/Makefile.vdsoinst
new file mode 100644
index 000000000..d9f724321
--- /dev/null
+++ b/scripts/Makefile.vdsoinst
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# ==========================================================================
+# Install unstripped copies of vDSO
+# ==========================================================================
+
+PHONY := __default
+__default:
+	@:
+
+include $(srctree)/scripts/Kbuild.include
+
+install-dir := $(MODLIB)/vdso
+
+define gen_install_rules
+
+dest := $(install-dir)/$$(patsubst %.dbg,%,$$(notdir $(1)))
+
+__default: $$(dest)
+$$(dest): $(1) FORCE
+	$$(call cmd,install)
+
+build-id-file := $$(shell $(READELF) -n $(1) 2>/dev/null | sed -n 's@^.*Build ID: \(..\)\(.*\)@\1/\2@p')
+
+ifneq ($$(build-id-file),)
+link := $(install-dir)/.build-id/$$(build-id-file).debug
+
+__default: $$(link)
+$$(link): $$(dest) FORCE
+	$$(call cmd,symlink)
+endif
+
+endef
+
+$(foreach x, $(sort $(INSTALL_FILES)), $(eval $(call gen_install_rules,$(x))))
+
+quiet_cmd_install = INSTALL $@
+      cmd_install = mkdir -p $(dir $@); cp $< $@
+
+quiet_cmd_symlink = SYMLINK $@
+      cmd_symlink = mkdir -p $(dir $@); ln -sf --relative $< $@
+
+PHONY += FORCE
+FORCE:
+
+.PHONY: $(PHONY)