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, 40 insertions, 0 deletions

diff --git a/lib/crypto/arm/blake2b.h b/lib/crypto/arm/blake2b.h
new file mode 100644
index 000000000..5c7649852
--- /dev/null
+++ b/lib/crypto/arm/blake2b.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * BLAKE2b digest algorithm, NEON accelerated
+ *
+ * Copyright 2020 Google LLC
+ */
+
+#include <asm/neon.h>
+#include <asm/simd.h>
+
+static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon);
+
+asmlinkage void blake2b_compress_neon(struct blake2b_ctx *ctx,
+				      const u8 *data, size_t nblocks, u32 inc);
+
+static void blake2b_compress(struct blake2b_ctx *ctx,
+			     const u8 *data, size_t nblocks, u32 inc)
+{
+	if (!static_branch_likely(&have_neon) || !may_use_simd()) {
+		blake2b_compress_generic(ctx, data, nblocks, inc);
+		return;
+	}
+	do {
+		const size_t blocks = min_t(size_t, nblocks,
+					    SZ_4K / BLAKE2B_BLOCK_SIZE);
+
+		scoped_ksimd()
+			blake2b_compress_neon(ctx, data, blocks, inc);
+
+		data += blocks * BLAKE2B_BLOCK_SIZE;
+		nblocks -= blocks;
+	} while (nblocks);
+}
+
+#define blake2b_mod_init_arch blake2b_mod_init_arch
+static void blake2b_mod_init_arch(void)
+{
+	if (elf_hwcap & HWCAP_NEON)
+		static_branch_enable(&have_neon);
+}