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, 133 insertions, 0 deletions

diff --git a/crypto/blowfish_generic.c b/crypto/blowfish_generic.c
new file mode 100644
index 000000000..f3c5f9b09
--- /dev/null
+++ b/crypto/blowfish_generic.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Cryptographic API.
+ *
+ * Blowfish Cipher Algorithm, by Bruce Schneier.
+ * http://www.counterpane.com/blowfish.html
+ *
+ * Adapted from Kerneli implementation.
+ *
+ * Copyright (c) Herbert Valerio Riedel <hvr@hvrlab.org>
+ * Copyright (c) Kyle McMartin <kyle@debian.org>
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ */
+
+#include <crypto/algapi.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/unaligned.h>
+#include <linux/types.h>
+#include <crypto/blowfish.h>
+
+/*
+ * Round loop unrolling macros, S is a pointer to a S-Box array
+ * organized in 4 unsigned longs at a row.
+ */
+#define GET32_3(x) (((x) & 0xff))
+#define GET32_2(x) (((x) >> (8)) & (0xff))
+#define GET32_1(x) (((x) >> (16)) & (0xff))
+#define GET32_0(x) (((x) >> (24)) & (0xff))
+
+#define bf_F(x) (((S[GET32_0(x)] + S[256 + GET32_1(x)]) ^ \
+		S[512 + GET32_2(x)]) + S[768 + GET32_3(x)])
+
+#define ROUND(a, b, n) ({ b ^= P[n]; a ^= bf_F(b); })
+
+static void bf_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+	struct bf_ctx *ctx = crypto_tfm_ctx(tfm);
+	const u32 *P = ctx->p;
+	const u32 *S = ctx->s;
+	u32 yl = get_unaligned_be32(src);
+	u32 yr = get_unaligned_be32(src + 4);
+
+	ROUND(yr, yl, 0);
+	ROUND(yl, yr, 1);
+	ROUND(yr, yl, 2);
+	ROUND(yl, yr, 3);
+	ROUND(yr, yl, 4);
+	ROUND(yl, yr, 5);
+	ROUND(yr, yl, 6);
+	ROUND(yl, yr, 7);
+	ROUND(yr, yl, 8);
+	ROUND(yl, yr, 9);
+	ROUND(yr, yl, 10);
+	ROUND(yl, yr, 11);
+	ROUND(yr, yl, 12);
+	ROUND(yl, yr, 13);
+	ROUND(yr, yl, 14);
+	ROUND(yl, yr, 15);
+
+	yl ^= P[16];
+	yr ^= P[17];
+
+	put_unaligned_be32(yr, dst);
+	put_unaligned_be32(yl, dst + 4);
+}
+
+static void bf_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+	struct bf_ctx *ctx = crypto_tfm_ctx(tfm);
+	const u32 *P = ctx->p;
+	const u32 *S = ctx->s;
+	u32 yl = get_unaligned_be32(src);
+	u32 yr = get_unaligned_be32(src + 4);
+
+	ROUND(yr, yl, 17);
+	ROUND(yl, yr, 16);
+	ROUND(yr, yl, 15);
+	ROUND(yl, yr, 14);
+	ROUND(yr, yl, 13);
+	ROUND(yl, yr, 12);
+	ROUND(yr, yl, 11);
+	ROUND(yl, yr, 10);
+	ROUND(yr, yl, 9);
+	ROUND(yl, yr, 8);
+	ROUND(yr, yl, 7);
+	ROUND(yl, yr, 6);
+	ROUND(yr, yl, 5);
+	ROUND(yl, yr, 4);
+	ROUND(yr, yl, 3);
+	ROUND(yl, yr, 2);
+
+	yl ^= P[1];
+	yr ^= P[0];
+
+	put_unaligned_be32(yr, dst);
+	put_unaligned_be32(yl, dst + 4);
+}
+
+static struct crypto_alg alg = {
+	.cra_name		=	"blowfish",
+	.cra_driver_name	=	"blowfish-generic",
+	.cra_priority		=	100,
+	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
+	.cra_blocksize		=	BF_BLOCK_SIZE,
+	.cra_ctxsize		=	sizeof(struct bf_ctx),
+	.cra_module		=	THIS_MODULE,
+	.cra_u			=	{ .cipher = {
+	.cia_min_keysize	=	BF_MIN_KEY_SIZE,
+	.cia_max_keysize	=	BF_MAX_KEY_SIZE,
+	.cia_setkey		=	blowfish_setkey,
+	.cia_encrypt		=	bf_encrypt,
+	.cia_decrypt		=	bf_decrypt } }
+};
+
+static int __init blowfish_mod_init(void)
+{
+	return crypto_register_alg(&alg);
+}
+
+static void __exit blowfish_mod_fini(void)
+{
+	crypto_unregister_alg(&alg);
+}
+
+module_init(blowfish_mod_init);
+module_exit(blowfish_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Blowfish Cipher Algorithm");
+MODULE_ALIAS_CRYPTO("blowfish");
+MODULE_ALIAS_CRYPTO("blowfish-generic");