From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- crypto/aes.c | 247 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 247 insertions(+) create mode 100644 crypto/aes.c (limited to 'crypto/aes.c') diff --git a/crypto/aes.c b/crypto/aes.c new file mode 100644 index 000000000..6bf23eb05 --- /dev/null +++ b/crypto/aes.c @@ -0,0 +1,247 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Crypto API support for AES block cipher + * + * Copyright 2026 Google LLC + */ + +#include +#include +#include +#include +#include + +static_assert(__alignof__(struct aes_key) <= CRYPTO_MINALIGN); + +static int crypto_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key, + unsigned int key_len) +{ + struct aes_key *key = crypto_tfm_ctx(tfm); + + return aes_preparekey(key, in_key, key_len); +} + +static void crypto_aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + const struct aes_key *key = crypto_tfm_ctx(tfm); + + aes_encrypt(key, out, in); +} + +static void crypto_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + const struct aes_key *key = crypto_tfm_ctx(tfm); + + aes_decrypt(key, out, in); +} + +static_assert(__alignof__(struct aes_cmac_key) <= CRYPTO_MINALIGN); +#define AES_CMAC_KEY(tfm) ((struct aes_cmac_key *)crypto_shash_ctx(tfm)) +#define AES_CMAC_CTX(desc) ((struct aes_cmac_ctx *)shash_desc_ctx(desc)) + +static int __maybe_unused crypto_aes_cmac_setkey(struct crypto_shash *tfm, + const u8 *in_key, + unsigned int key_len) +{ + return aes_cmac_preparekey(AES_CMAC_KEY(tfm), in_key, key_len); +} + +static int __maybe_unused crypto_aes_xcbc_setkey(struct crypto_shash *tfm, + const u8 *in_key, + unsigned int key_len) +{ + if (key_len != AES_KEYSIZE_128) + return -EINVAL; + aes_xcbcmac_preparekey(AES_CMAC_KEY(tfm), in_key); + return 0; +} + +static int __maybe_unused crypto_aes_cmac_init(struct shash_desc *desc) +{ + aes_cmac_init(AES_CMAC_CTX(desc), AES_CMAC_KEY(desc->tfm)); + return 0; +} + +static int __maybe_unused crypto_aes_cmac_update(struct shash_desc *desc, + const u8 *data, + unsigned int len) +{ + aes_cmac_update(AES_CMAC_CTX(desc), data, len); + return 0; +} + +static int __maybe_unused crypto_aes_cmac_final(struct shash_desc *desc, + u8 *out) +{ + aes_cmac_final(AES_CMAC_CTX(desc), out); + return 0; +} + +static int __maybe_unused crypto_aes_cmac_digest(struct shash_desc *desc, + const u8 *data, + unsigned int len, u8 *out) +{ + aes_cmac(AES_CMAC_KEY(desc->tfm), data, len, out); + return 0; +} + +static_assert(__alignof__(struct aes_enckey) <= CRYPTO_MINALIGN); +#define AES_CBCMAC_KEY(tfm) ((struct aes_enckey *)crypto_shash_ctx(tfm)) +#define AES_CBCMAC_CTX(desc) ((struct aes_cbcmac_ctx *)shash_desc_ctx(desc)) + +static int __maybe_unused crypto_aes_cbcmac_setkey(struct crypto_shash *tfm, + const u8 *in_key, + unsigned int key_len) +{ + return aes_prepareenckey(AES_CBCMAC_KEY(tfm), in_key, key_len); +} + +static int __maybe_unused crypto_aes_cbcmac_init(struct shash_desc *desc) +{ + aes_cbcmac_init(AES_CBCMAC_CTX(desc), AES_CBCMAC_KEY(desc->tfm)); + return 0; +} + +static int __maybe_unused crypto_aes_cbcmac_update(struct shash_desc *desc, + const u8 *data, + unsigned int len) +{ + aes_cbcmac_update(AES_CBCMAC_CTX(desc), data, len); + return 0; +} + +static int __maybe_unused crypto_aes_cbcmac_final(struct shash_desc *desc, + u8 *out) +{ + aes_cbcmac_final(AES_CBCMAC_CTX(desc), out); + return 0; +} + +static int __maybe_unused crypto_aes_cbcmac_digest(struct shash_desc *desc, + const u8 *data, + unsigned int len, u8 *out) +{ + aes_cbcmac_init(AES_CBCMAC_CTX(desc), AES_CBCMAC_KEY(desc->tfm)); + aes_cbcmac_update(AES_CBCMAC_CTX(desc), data, len); + aes_cbcmac_final(AES_CBCMAC_CTX(desc), out); + return 0; +} + +static struct crypto_alg alg = { + .cra_name = "aes", + .cra_driver_name = "aes-lib", + .cra_priority = 100, + .cra_flags = CRYPTO_ALG_TYPE_CIPHER, + .cra_blocksize = AES_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct aes_key), + .cra_module = THIS_MODULE, + .cra_u = { .cipher = { .cia_min_keysize = AES_MIN_KEY_SIZE, + .cia_max_keysize = AES_MAX_KEY_SIZE, + .cia_setkey = crypto_aes_setkey, + .cia_encrypt = crypto_aes_encrypt, + .cia_decrypt = crypto_aes_decrypt } } +}; + +static struct shash_alg mac_algs[] = { +#if IS_ENABLED(CONFIG_CRYPTO_CMAC) + { + .base.cra_name = "cmac(aes)", + .base.cra_driver_name = "cmac-aes-lib", + .base.cra_priority = 300, + .base.cra_blocksize = AES_BLOCK_SIZE, + .base.cra_ctxsize = sizeof(struct aes_cmac_key), + .base.cra_module = THIS_MODULE, + .digestsize = AES_BLOCK_SIZE, + .setkey = crypto_aes_cmac_setkey, + .init = crypto_aes_cmac_init, + .update = crypto_aes_cmac_update, + .final = crypto_aes_cmac_final, + .digest = crypto_aes_cmac_digest, + .descsize = sizeof(struct aes_cmac_ctx), + }, +#endif +#if IS_ENABLED(CONFIG_CRYPTO_XCBC) + { + /* + * Note that the only difference between xcbc(aes) and cmac(aes) + * is the preparekey function. + */ + .base.cra_name = "xcbc(aes)", + .base.cra_driver_name = "xcbc-aes-lib", + .base.cra_priority = 300, + .base.cra_blocksize = AES_BLOCK_SIZE, + .base.cra_ctxsize = sizeof(struct aes_cmac_key), + .base.cra_module = THIS_MODULE, + .digestsize = AES_BLOCK_SIZE, + .setkey = crypto_aes_xcbc_setkey, + .init = crypto_aes_cmac_init, + .update = crypto_aes_cmac_update, + .final = crypto_aes_cmac_final, + .digest = crypto_aes_cmac_digest, + .descsize = sizeof(struct aes_cmac_ctx), + }, +#endif +#if IS_ENABLED(CONFIG_CRYPTO_CCM) + { + .base.cra_name = "cbcmac(aes)", + .base.cra_driver_name = "cbcmac-aes-lib", + .base.cra_priority = 300, + .base.cra_blocksize = AES_BLOCK_SIZE, + .base.cra_ctxsize = sizeof(struct aes_enckey), + .base.cra_module = THIS_MODULE, + .digestsize = AES_BLOCK_SIZE, + .setkey = crypto_aes_cbcmac_setkey, + .init = crypto_aes_cbcmac_init, + .update = crypto_aes_cbcmac_update, + .final = crypto_aes_cbcmac_final, + .digest = crypto_aes_cbcmac_digest, + .descsize = sizeof(struct aes_cbcmac_ctx), + }, +#endif +}; + +static int __init crypto_aes_mod_init(void) +{ + int err = crypto_register_alg(&alg); + + if (err) + return err; + + if (ARRAY_SIZE(mac_algs) > 0) { + err = crypto_register_shashes(mac_algs, ARRAY_SIZE(mac_algs)); + if (err) + goto err_unregister_alg; + } /* Else, CONFIG_CRYPTO_HASH might not be enabled. */ + return 0; + +err_unregister_alg: + crypto_unregister_alg(&alg); + return err; +} +module_init(crypto_aes_mod_init); + +static void __exit crypto_aes_mod_exit(void) +{ + if (ARRAY_SIZE(mac_algs) > 0) + crypto_unregister_shashes(mac_algs, ARRAY_SIZE(mac_algs)); + crypto_unregister_alg(&alg); +} +module_exit(crypto_aes_mod_exit); + +MODULE_DESCRIPTION("Crypto API support for AES block cipher"); +MODULE_IMPORT_NS("CRYPTO_INTERNAL"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CRYPTO("aes"); +MODULE_ALIAS_CRYPTO("aes-lib"); +#if IS_ENABLED(CONFIG_CRYPTO_CMAC) +MODULE_ALIAS_CRYPTO("cmac(aes)"); +MODULE_ALIAS_CRYPTO("cmac-aes-lib"); +#endif +#if IS_ENABLED(CONFIG_CRYPTO_XCBC) +MODULE_ALIAS_CRYPTO("xcbc(aes)"); +MODULE_ALIAS_CRYPTO("xcbc-aes-lib"); +#endif +#if IS_ENABLED(CONFIG_CRYPTO_CCM) +MODULE_ALIAS_CRYPTO("cbcmac(aes)"); +MODULE_ALIAS_CRYPTO("cbcmac-aes-lib"); +#endif -- cgit v1.3.1