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, 49 insertions, 0 deletions

diff --git a/include/crypto/chacha20poly1305.h b/include/crypto/chacha20poly1305.h
new file mode 100644
index 000000000..0f6d99170
--- /dev/null
+++ b/include/crypto/chacha20poly1305.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef __CHACHA20POLY1305_H
+#define __CHACHA20POLY1305_H
+
+#include <linux/types.h>
+#include <linux/scatterlist.h>
+
+enum chacha20poly1305_lengths {
+	XCHACHA20POLY1305_NONCE_SIZE = 24,
+	CHACHA20POLY1305_KEY_SIZE = 32,
+	CHACHA20POLY1305_AUTHTAG_SIZE = 16
+};
+
+void chacha20poly1305_encrypt(u8 *dst, const u8 *src, const size_t src_len,
+			      const u8 *ad, const size_t ad_len,
+			      const u64 nonce,
+			      const u8 key[at_least CHACHA20POLY1305_KEY_SIZE]);
+
+bool __must_check
+chacha20poly1305_decrypt(u8 *dst, const u8 *src, const size_t src_len,
+			 const u8 *ad, const size_t ad_len, const u64 nonce,
+			 const u8 key[at_least CHACHA20POLY1305_KEY_SIZE]);
+
+void xchacha20poly1305_encrypt(u8 *dst, const u8 *src, const size_t src_len,
+			       const u8 *ad, const size_t ad_len,
+			       const u8 nonce[at_least XCHACHA20POLY1305_NONCE_SIZE],
+			       const u8 key[at_least CHACHA20POLY1305_KEY_SIZE]);
+
+bool __must_check xchacha20poly1305_decrypt(
+	u8 *dst, const u8 *src, const size_t src_len,
+	const u8 *ad, const size_t ad_len,
+	const u8 nonce[at_least XCHACHA20POLY1305_NONCE_SIZE],
+	const u8 key[at_least CHACHA20POLY1305_KEY_SIZE]);
+
+bool chacha20poly1305_encrypt_sg_inplace(struct scatterlist *src, size_t src_len,
+					 const u8 *ad, const size_t ad_len,
+					 const u64 nonce,
+					 const u8 key[at_least CHACHA20POLY1305_KEY_SIZE]);
+
+bool chacha20poly1305_decrypt_sg_inplace(struct scatterlist *src, size_t src_len,
+					 const u8 *ad, const size_t ad_len,
+					 const u64 nonce,
+					 const u8 key[at_least CHACHA20POLY1305_KEY_SIZE]);
+
+#endif /* __CHACHA20POLY1305_H */