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, 52 insertions, 0 deletions

diff --git a/io_uring/memmap.h b/io_uring/memmap.h
new file mode 100644
index 000000000..f4cfbb6b9
--- /dev/null
+++ b/io_uring/memmap.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef IO_URING_MEMMAP_H
+#define IO_URING_MEMMAP_H
+
+#define IORING_MAP_OFF_PARAM_REGION		0x20000000ULL
+#define IORING_MAP_OFF_ZCRX_REGION		0x30000000ULL
+
+#define IORING_OFF_ZCRX_SHIFT		16
+
+struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages);
+
+#ifndef CONFIG_MMU
+unsigned int io_uring_nommu_mmap_capabilities(struct file *file);
+#endif
+unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr,
+					 unsigned long len, unsigned long pgoff,
+					 unsigned long flags);
+int io_uring_mmap(struct file *file, struct vm_area_struct *vma);
+
+void io_free_region(struct user_struct *user, struct io_mapped_region *mr);
+int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr,
+		     struct io_uring_region_desc *reg,
+		     unsigned long mmap_offset);
+
+static inline void *io_region_get_ptr(struct io_mapped_region *mr)
+{
+	return mr->ptr;
+}
+
+static inline bool io_region_is_set(struct io_mapped_region *mr)
+{
+	return !!mr->nr_pages;
+}
+
+static inline void io_region_publish(struct io_ring_ctx *ctx,
+				     struct io_mapped_region *src_region,
+				     struct io_mapped_region *dst_region)
+{
+	/*
+	 * Once published mmap can find it without holding only the ->mmap_lock
+	 * and not ->uring_lock.
+	 */
+	guard(mutex)(&ctx->mmap_lock);
+	*dst_region = *src_region;
+}
+
+static inline size_t io_region_size(struct io_mapped_region *mr)
+{
+	return (size_t) mr->nr_pages << PAGE_SHIFT;
+}
+
+#endif