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, 40 insertions, 0 deletions

diff --git a/include/xen/balloon.h b/include/xen/balloon.h
new file mode 100644
index 000000000..f78a6cc94
--- /dev/null
+++ b/include/xen/balloon.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/******************************************************************************
+ * Xen balloon functionality
+ */
+#ifndef _XEN_BALLOON_H
+#define _XEN_BALLOON_H
+
+#define RETRY_UNLIMITED	0
+
+struct balloon_stats {
+	/* We aim for 'current allocation' == 'target allocation'. */
+	unsigned long current_pages;
+	unsigned long target_pages;
+	unsigned long target_unpopulated;
+	/* Number of pages in high- and low-memory balloons. */
+	unsigned long balloon_low;
+	unsigned long balloon_high;
+	unsigned long total_pages;
+	unsigned long schedule_delay;
+	unsigned long max_schedule_delay;
+	unsigned long retry_count;
+	unsigned long max_retry_count;
+};
+
+extern struct balloon_stats balloon_stats;
+
+void balloon_set_new_target(unsigned long target);
+
+int xen_alloc_ballooned_pages(unsigned int nr_pages, struct page **pages);
+void xen_free_ballooned_pages(unsigned int nr_pages, struct page **pages);
+
+#ifdef CONFIG_XEN_BALLOON
+void xen_balloon_init(void);
+#else
+static inline void xen_balloon_init(void)
+{
+}
+#endif
+
+#endif	/* _XEN_BALLOON_H */