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, 53 insertions, 0 deletions

diff --git a/io_uring/rw.h b/io_uring/rw.h
new file mode 100644
index 000000000..1179506f9
--- /dev/null
+++ b/io_uring/rw.h
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/io_uring_types.h>
+#include <linux/pagemap.h>
+#include <linux/uio.h>
+
+struct io_meta_state {
+	u32			seed;
+	struct iov_iter_state	iter_meta;
+};
+
+struct io_async_rw {
+	struct iou_vec			vec;
+	size_t				bytes_done;
+
+	struct_group(clear,
+		struct iov_iter			iter;
+		struct iov_iter_state		iter_state;
+		struct iovec			fast_iov;
+		unsigned			buf_group;
+
+		/*
+		 * wpq is for buffered io, while meta fields are used with
+		 * direct io
+		 */
+		union {
+			struct wait_page_queue		wpq;
+			struct {
+				struct uio_meta			meta;
+				struct io_meta_state		meta_state;
+			};
+		};
+	);
+};
+
+int io_prep_read_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_write_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_readv_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_writev_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_readv(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_writev(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_read(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_prep_write(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_read(struct io_kiocb *req, unsigned int issue_flags);
+int io_write(struct io_kiocb *req, unsigned int issue_flags);
+int io_read_fixed(struct io_kiocb *req, unsigned int issue_flags);
+int io_write_fixed(struct io_kiocb *req, unsigned int issue_flags);
+void io_readv_writev_cleanup(struct io_kiocb *req);
+void io_rw_fail(struct io_kiocb *req);
+void io_req_rw_complete(struct io_tw_req tw_req, io_tw_token_t tw);
+int io_read_mshot_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_read_mshot(struct io_kiocb *req, unsigned int issue_flags);
+void io_rw_cache_free(const void *entry);