From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- crypto/xxhash_generic.c | 106 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 crypto/xxhash_generic.c (limited to 'crypto/xxhash_generic.c') diff --git a/crypto/xxhash_generic.c b/crypto/xxhash_generic.c new file mode 100644 index 000000000..175bb7ae0 --- /dev/null +++ b/crypto/xxhash_generic.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include + +#define XXHASH64_BLOCK_SIZE 32 +#define XXHASH64_DIGEST_SIZE 8 + +struct xxhash64_tfm_ctx { + u64 seed; +}; + +struct xxhash64_desc_ctx { + struct xxh64_state xxhstate; +}; + +static int xxhash64_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(tfm); + + if (keylen != sizeof(tctx->seed)) + return -EINVAL; + tctx->seed = get_unaligned_le64(key); + return 0; +} + +static int xxhash64_init(struct shash_desc *desc) +{ + struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); + struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc); + + xxh64_reset(&dctx->xxhstate, tctx->seed); + + return 0; +} + +static int xxhash64_update(struct shash_desc *desc, const u8 *data, + unsigned int length) +{ + struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc); + + xxh64_update(&dctx->xxhstate, data, length); + + return 0; +} + +static int xxhash64_final(struct shash_desc *desc, u8 *out) +{ + struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc); + + put_unaligned_le64(xxh64_digest(&dctx->xxhstate), out); + + return 0; +} + +static int xxhash64_digest(struct shash_desc *desc, const u8 *data, + unsigned int length, u8 *out) +{ + struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); + + put_unaligned_le64(xxh64(data, length, tctx->seed), out); + + return 0; +} + +static struct shash_alg alg = { + .digestsize = XXHASH64_DIGEST_SIZE, + .setkey = xxhash64_setkey, + .init = xxhash64_init, + .update = xxhash64_update, + .final = xxhash64_final, + .digest = xxhash64_digest, + .descsize = sizeof(struct xxhash64_desc_ctx), + .base = { + .cra_name = "xxhash64", + .cra_driver_name = "xxhash64-generic", + .cra_priority = 100, + .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, + .cra_blocksize = XXHASH64_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct xxhash64_tfm_ctx), + .cra_module = THIS_MODULE, + } +}; + +static int __init xxhash_mod_init(void) +{ + return crypto_register_shash(&alg); +} + +static void __exit xxhash_mod_fini(void) +{ + crypto_unregister_shash(&alg); +} + +module_init(xxhash_mod_init); +module_exit(xxhash_mod_fini); + +MODULE_AUTHOR("Nikolay Borisov "); +MODULE_DESCRIPTION("xxhash calculations wrapper for lib/xxhash.c"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CRYPTO("xxhash64"); +MODULE_ALIAS_CRYPTO("xxhash64-generic"); -- cgit v1.3.1