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/poly1305.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 lib/crypto/poly1305.c (limited to 'lib/crypto/poly1305.c') diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c new file mode 100644 index 000000000..f313ccc4b --- /dev/null +++ b/lib/crypto/poly1305.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Poly1305 authenticator algorithm, RFC7539 + * + * Copyright (C) 2015 Martin Willi + * + * Based on public domain code by Andrew Moon and Daniel J. Bernstein. + */ + +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_CRYPTO_LIB_POLY1305_ARCH +#include "poly1305.h" /* $(SRCARCH)/poly1305.h */ +#else +#define poly1305_block_init poly1305_block_init_generic +#define poly1305_blocks poly1305_blocks_generic +#define poly1305_emit poly1305_emit_generic +#endif + +void poly1305_init(struct poly1305_desc_ctx *desc, + const u8 key[POLY1305_KEY_SIZE]) +{ + desc->s[0] = get_unaligned_le32(key + 16); + desc->s[1] = get_unaligned_le32(key + 20); + desc->s[2] = get_unaligned_le32(key + 24); + desc->s[3] = get_unaligned_le32(key + 28); + desc->buflen = 0; + poly1305_block_init(&desc->state, key); +} +EXPORT_SYMBOL(poly1305_init); + +void poly1305_update(struct poly1305_desc_ctx *desc, + const u8 *src, unsigned int nbytes) +{ + if (desc->buflen + nbytes >= POLY1305_BLOCK_SIZE) { + unsigned int bulk_len; + + if (desc->buflen) { + unsigned int l = POLY1305_BLOCK_SIZE - desc->buflen; + + memcpy(&desc->buf[desc->buflen], src, l); + src += l; + nbytes -= l; + + poly1305_blocks(&desc->state, desc->buf, + POLY1305_BLOCK_SIZE, 1); + desc->buflen = 0; + } + + bulk_len = round_down(nbytes, POLY1305_BLOCK_SIZE); + nbytes %= POLY1305_BLOCK_SIZE; + + if (bulk_len) { + poly1305_blocks(&desc->state, src, bulk_len, 1); + src += bulk_len; + } + } + if (nbytes) { + memcpy(&desc->buf[desc->buflen], src, nbytes); + desc->buflen += nbytes; + } +} +EXPORT_SYMBOL(poly1305_update); + +void poly1305_final(struct poly1305_desc_ctx *desc, u8 *dst) +{ + if (unlikely(desc->buflen)) { + desc->buf[desc->buflen++] = 1; + memset(desc->buf + desc->buflen, 0, + POLY1305_BLOCK_SIZE - desc->buflen); + poly1305_blocks(&desc->state, desc->buf, POLY1305_BLOCK_SIZE, + 0); + } + + poly1305_emit(&desc->state.h, dst, desc->s); + *desc = (struct poly1305_desc_ctx){}; +} +EXPORT_SYMBOL(poly1305_final); + +#ifdef poly1305_mod_init_arch +static int __init poly1305_mod_init(void) +{ + poly1305_mod_init_arch(); + return 0; +} +subsys_initcall(poly1305_mod_init); + +static void __exit poly1305_mod_exit(void) +{ +} +module_exit(poly1305_mod_exit); +#endif + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Poly1305 authenticator algorithm, RFC7539"); -- cgit v1.3.1