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 --- lib/crypto/chacha.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 lib/crypto/chacha.c (limited to 'lib/crypto/chacha.c') diff --git a/lib/crypto/chacha.c b/lib/crypto/chacha.c new file mode 100644 index 000000000..86e5d382a --- /dev/null +++ b/lib/crypto/chacha.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * The ChaCha stream cipher (RFC7539) + * + * Copyright (C) 2015 Martin Willi + */ + +#include +#include +#include +#include +#include + +static void __maybe_unused +chacha_crypt_generic(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) +{ + /* aligned to potentially speed up crypto_xor() */ + u8 stream[CHACHA_BLOCK_SIZE] __aligned(sizeof(long)); + + while (bytes >= CHACHA_BLOCK_SIZE) { + chacha_block_generic(state, stream, nrounds); + crypto_xor_cpy(dst, src, stream, CHACHA_BLOCK_SIZE); + bytes -= CHACHA_BLOCK_SIZE; + dst += CHACHA_BLOCK_SIZE; + src += CHACHA_BLOCK_SIZE; + } + if (bytes) { + chacha_block_generic(state, stream, nrounds); + crypto_xor_cpy(dst, src, stream, bytes); + } +} + +#ifdef CONFIG_CRYPTO_LIB_CHACHA_ARCH +#include "chacha.h" /* $(SRCARCH)/chacha.h */ +#else +#define chacha_crypt_arch chacha_crypt_generic +#define hchacha_block_arch hchacha_block_generic +#endif + +void chacha_crypt(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) +{ + chacha_crypt_arch(state, dst, src, bytes, nrounds); +} +EXPORT_SYMBOL_GPL(chacha_crypt); + +void hchacha_block(const struct chacha_state *state, + u32 out[HCHACHA_OUT_WORDS], int nrounds) +{ + hchacha_block_arch(state, out, nrounds); +} +EXPORT_SYMBOL_GPL(hchacha_block); + +#ifdef chacha_mod_init_arch +static int __init chacha_mod_init(void) +{ + chacha_mod_init_arch(); + return 0; +} +subsys_initcall(chacha_mod_init); + +static void __exit chacha_mod_exit(void) +{ +} +module_exit(chacha_mod_exit); +#endif + +MODULE_DESCRIPTION("ChaCha stream cipher (RFC7539)"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1