From ff917923f4fb9c83717ba135ee47d7e4c1567bb7 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Tue, 28 Jul 2026 17:54:55 +0500 Subject: staging: rtl8723bs: fix OOB read in rtw_action_frame_parse() 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 Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman --- crypto/chacha.c | 175 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 crypto/chacha.c (limited to 'crypto/chacha.c') diff --git a/crypto/chacha.c b/crypto/chacha.c new file mode 100644 index 000000000..ec16d5a33 --- /dev/null +++ b/crypto/chacha.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Crypto API wrappers for the ChaCha20, XChaCha20, and XChaCha12 stream ciphers + * + * Copyright (C) 2015 Martin Willi + * Copyright (C) 2018 Google LLC + */ + +#include +#include +#include +#include +#include + +struct chacha_ctx { + u32 key[8]; + int nrounds; +}; + +static int chacha_setkey(struct crypto_skcipher *tfm, + const u8 *key, unsigned int keysize, int nrounds) +{ + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); + int i; + + if (keysize != CHACHA_KEY_SIZE) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(ctx->key); i++) + ctx->key[i] = get_unaligned_le32(key + i * sizeof(u32)); + + ctx->nrounds = nrounds; + return 0; +} + +static int chacha20_setkey(struct crypto_skcipher *tfm, + const u8 *key, unsigned int keysize) +{ + return chacha_setkey(tfm, key, keysize, 20); +} + +static int chacha12_setkey(struct crypto_skcipher *tfm, + const u8 *key, unsigned int keysize) +{ + return chacha_setkey(tfm, key, keysize, 12); +} + +static int chacha_stream_xor(struct skcipher_request *req, + const struct chacha_ctx *ctx, + const u8 iv[CHACHA_IV_SIZE]) +{ + struct skcipher_walk walk; + struct chacha_state state; + int err; + + err = skcipher_walk_virt(&walk, req, false); + + chacha_init(&state, ctx->key, iv); + + while (walk.nbytes > 0) { + unsigned int nbytes = walk.nbytes; + + if (nbytes < walk.total) + nbytes = round_down(nbytes, CHACHA_BLOCK_SIZE); + + chacha_crypt(&state, walk.dst.virt.addr, walk.src.virt.addr, + nbytes, ctx->nrounds); + err = skcipher_walk_done(&walk, walk.nbytes - nbytes); + } + + return err; +} + +static int crypto_chacha_crypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + const struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); + + return chacha_stream_xor(req, ctx, req->iv); +} + +static int crypto_xchacha_crypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + const struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); + struct chacha_ctx subctx; + struct chacha_state state; + u8 real_iv[16]; + + /* Compute the subkey given the original key and first 128 nonce bits */ + chacha_init(&state, ctx->key, req->iv); + hchacha_block(&state, subctx.key, ctx->nrounds); + subctx.nrounds = ctx->nrounds; + + /* Build the real IV */ + memcpy(&real_iv[0], req->iv + 24, 8); /* stream position */ + memcpy(&real_iv[8], req->iv + 16, 8); /* remaining 64 nonce bits */ + + /* Generate the stream and XOR it with the data */ + return chacha_stream_xor(req, &subctx, real_iv); +} + +static struct skcipher_alg algs[] = { + { + .base.cra_name = "chacha20", + .base.cra_driver_name = "chacha20-lib", + .base.cra_priority = 300, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = CHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .setkey = chacha20_setkey, + .encrypt = crypto_chacha_crypt, + .decrypt = crypto_chacha_crypt, + }, + { + .base.cra_name = "xchacha20", + .base.cra_driver_name = "xchacha20-lib", + .base.cra_priority = 300, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = XCHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .setkey = chacha20_setkey, + .encrypt = crypto_xchacha_crypt, + .decrypt = crypto_xchacha_crypt, + }, + { + .base.cra_name = "xchacha12", + .base.cra_driver_name = "xchacha12-lib", + .base.cra_priority = 300, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha_ctx), + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = XCHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, + .setkey = chacha12_setkey, + .encrypt = crypto_xchacha_crypt, + .decrypt = crypto_xchacha_crypt, + } +}; + +static int __init crypto_chacha_mod_init(void) +{ + return crypto_register_skciphers(algs, ARRAY_SIZE(algs)); +} + +static void __exit crypto_chacha_mod_fini(void) +{ + crypto_unregister_skciphers(algs, ARRAY_SIZE(algs)); +} + +module_init(crypto_chacha_mod_init); +module_exit(crypto_chacha_mod_fini); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Martin Willi "); +MODULE_DESCRIPTION("Crypto API wrappers for the ChaCha20, XChaCha20, and XChaCha12 stream ciphers"); +MODULE_ALIAS_CRYPTO("chacha20"); +MODULE_ALIAS_CRYPTO("chacha20-lib"); +MODULE_ALIAS_CRYPTO("xchacha20"); +MODULE_ALIAS_CRYPTO("xchacha20-lib"); +MODULE_ALIAS_CRYPTO("xchacha12"); +MODULE_ALIAS_CRYPTO("xchacha12-lib"); -- cgit v1.3.1