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, 73 insertions, 0 deletions

diff --git a/tools/perf/util/blake2s.h b/tools/perf/util/blake2s.h
new file mode 100644
index 000000000..a1fe81a4b
--- /dev/null
+++ b/tools/perf/util/blake2s.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _CRYPTO_BLAKE2S_H
+#define _CRYPTO_BLAKE2S_H
+
+#include <string.h>
+#include <linux/types.h>
+
+#define BLAKE2S_BLOCK_SIZE 64
+
+struct blake2s_ctx {
+	u32 h[8];
+	u32 t[2];
+	u32 f[2];
+	u8 buf[BLAKE2S_BLOCK_SIZE];
+	unsigned int buflen;
+	unsigned int outlen;
+};
+
+enum blake2s_iv {
+	BLAKE2S_IV0 = 0x6A09E667UL,
+	BLAKE2S_IV1 = 0xBB67AE85UL,
+	BLAKE2S_IV2 = 0x3C6EF372UL,
+	BLAKE2S_IV3 = 0xA54FF53AUL,
+	BLAKE2S_IV4 = 0x510E527FUL,
+	BLAKE2S_IV5 = 0x9B05688CUL,
+	BLAKE2S_IV6 = 0x1F83D9ABUL,
+	BLAKE2S_IV7 = 0x5BE0CD19UL,
+};
+
+static inline void __blake2s_init(struct blake2s_ctx *ctx, size_t outlen,
+				  const void *key, size_t keylen)
+{
+	ctx->h[0] = BLAKE2S_IV0 ^ (0x01010000 | keylen << 8 | outlen);
+	ctx->h[1] = BLAKE2S_IV1;
+	ctx->h[2] = BLAKE2S_IV2;
+	ctx->h[3] = BLAKE2S_IV3;
+	ctx->h[4] = BLAKE2S_IV4;
+	ctx->h[5] = BLAKE2S_IV5;
+	ctx->h[6] = BLAKE2S_IV6;
+	ctx->h[7] = BLAKE2S_IV7;
+	ctx->t[0] = 0;
+	ctx->t[1] = 0;
+	ctx->f[0] = 0;
+	ctx->f[1] = 0;
+	ctx->buflen = 0;
+	ctx->outlen = outlen;
+	if (keylen) {
+		memcpy(ctx->buf, key, keylen);
+		memset(&ctx->buf[keylen], 0, BLAKE2S_BLOCK_SIZE - keylen);
+		ctx->buflen = BLAKE2S_BLOCK_SIZE;
+	}
+}
+
+static inline void blake2s_init(struct blake2s_ctx *ctx, size_t outlen)
+{
+	__blake2s_init(ctx, outlen, NULL, 0);
+}
+
+static inline void blake2s_init_key(struct blake2s_ctx *ctx, size_t outlen,
+				    const void *key, size_t keylen)
+{
+	__blake2s_init(ctx, outlen, key, keylen);
+}
+
+void blake2s_update(struct blake2s_ctx *ctx, const u8 *in, size_t inlen);
+
+void blake2s_final(struct blake2s_ctx *ctx, u8 *out);
+
+#endif /* _CRYPTO_BLAKE2S_H */