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, 87 insertions, 0 deletions

diff --git a/include/crypto/sm3.h b/include/crypto/sm3.h
new file mode 100644
index 000000000..371e8a661
--- /dev/null
+++ b/include/crypto/sm3.h
@@ -0,0 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * SM3 hash algorithm
+ *
+ * Copyright (C) 2017 ARM Limited or its affiliates.
+ * Copyright (C) 2017 Gilad Ben-Yossef <gilad@benyossef.com>
+ * Copyright (C) 2021 Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
+ */
+
+#ifndef _CRYPTO_SM3_H
+#define _CRYPTO_SM3_H
+
+#include <linux/types.h>
+
+#define SM3_DIGEST_SIZE	32
+#define SM3_BLOCK_SIZE	64
+
+#define SM3_IVA		0x7380166f
+#define SM3_IVB		0x4914b2b9
+#define SM3_IVC		0x172442d7
+#define SM3_IVD		0xda8a0600
+#define SM3_IVE		0xa96f30bc
+#define SM3_IVF		0x163138aa
+#define SM3_IVG		0xe38dee4d
+#define SM3_IVH		0xb0fb0e4e
+
+/* State for the SM3 compression function */
+struct sm3_block_state {
+	u32 h[SM3_DIGEST_SIZE / 4];
+};
+
+/**
+ * struct sm3_ctx - Context for hashing a message with SM3
+ * @state: the compression function state
+ * @bytecount: number of bytes processed so far
+ * @buf: partial block buffer; bytecount % SM3_BLOCK_SIZE bytes are valid
+ */
+struct sm3_ctx {
+	struct sm3_block_state state;
+	u64 bytecount;
+	u8 buf[SM3_BLOCK_SIZE] __aligned(__alignof__(__be64));
+};
+
+/**
+ * sm3_init() - Initialize an SM3 context for a new message
+ * @ctx: the context to initialize
+ *
+ * If you don't need incremental computation, consider sm3() instead.
+ *
+ * Context: Any context.
+ */
+void sm3_init(struct sm3_ctx *ctx);
+
+/**
+ * sm3_update() - Update an SM3 context with message data
+ * @ctx: the context to update; must have been initialized
+ * @data: the message data
+ * @len: the data length in bytes
+ *
+ * This can be called any number of times.
+ *
+ * Context: Any context.
+ */
+void sm3_update(struct sm3_ctx *ctx, const u8 *data, size_t len);
+
+/**
+ * sm3_final() - Finish computing an SM3 message digest
+ * @ctx: the context to finalize; must have been initialized
+ * @out: (output) the resulting SM3 message digest
+ *
+ * After finishing, this zeroizes @ctx.  So the caller does not need to do it.
+ *
+ * Context: Any context.
+ */
+void sm3_final(struct sm3_ctx *ctx, u8 out[at_least SM3_DIGEST_SIZE]);
+
+/**
+ * sm3() - Compute SM3 message digest in one shot
+ * @data: the message data
+ * @len: the data length in bytes
+ * @out: (output) the resulting SM3 message digest
+ *
+ * Context: Any context.
+ */
+void sm3(const u8 *data, size_t len, u8 out[at_least SM3_DIGEST_SIZE]);
+
+#endif /* _CRYPTO_SM3_H */