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 --- drivers/firmware/efi/tpm.c | 116 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 drivers/firmware/efi/tpm.c (limited to 'drivers/firmware/efi/tpm.c') diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c new file mode 100644 index 000000000..cdd431027 --- /dev/null +++ b/drivers/firmware/efi/tpm.c @@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2017 Google, Inc. + * Thiebaud Weksteen + */ + +#define TPM_MEMREMAP(start, size) early_memremap(start, size) +#define TPM_MEMUNMAP(start, size) early_memunmap(start, size) + +#include +#include +#include +#include +#include + +int efi_tpm_final_log_size; +EXPORT_SYMBOL(efi_tpm_final_log_size); + +static int __init tpm2_calc_event_log_size(void *data, int count, void *size_info) +{ + struct tcg_pcr_event2_head *header; + u32 event_size, size = 0; + + while (count > 0) { + header = data + size; + event_size = __calc_tpm2_event_size(header, size_info, true); + if (event_size == 0) + return -1; + size += event_size; + count--; + } + + return size; +} + +/* + * Reserve the memory associated with the TPM Event Log configuration table. + */ +int __init efi_tpm_eventlog_init(void) +{ + struct linux_efi_tpm_eventlog *log_tbl; + struct efi_tcg2_final_events_table *final_tbl; + unsigned int tbl_size; + int final_tbl_size; + int ret = 0; + + if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) { + /* + * We can't calculate the size of the final events without the + * first entry in the TPM log, so bail here. + */ + return 0; + } + + log_tbl = early_memremap(efi.tpm_log, sizeof(*log_tbl)); + if (!log_tbl) { + pr_err("Failed to map TPM Event Log table @ 0x%lx\n", + efi.tpm_log); + efi.tpm_log = EFI_INVALID_TABLE_ADDR; + return -ENOMEM; + } + + tbl_size = sizeof(*log_tbl) + log_tbl->size; + if (memblock_reserve(efi.tpm_log, tbl_size)) { + pr_err("TPM Event Log memblock reserve fails (0x%lx, 0x%x)\n", + efi.tpm_log, tbl_size); + ret = -ENOMEM; + goto out; + } + + if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) { + pr_info("TPM Final Events table not present\n"); + goto out; + } else if (log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) { + pr_warn(FW_BUG "TPM Final Events table invalid\n"); + goto out; + } + + final_tbl = early_memremap(efi.tpm_final_log, sizeof(*final_tbl)); + + if (!final_tbl) { + pr_err("Failed to map TPM Final Event Log table @ 0x%lx\n", + efi.tpm_final_log); + efi.tpm_final_log = EFI_INVALID_TABLE_ADDR; + ret = -ENOMEM; + goto out; + } + + final_tbl_size = 0; + if (final_tbl->nr_events != 0) { + void *events = (void *)efi.tpm_final_log + + sizeof(final_tbl->version) + + sizeof(final_tbl->nr_events); + + final_tbl_size = tpm2_calc_event_log_size(events, + final_tbl->nr_events, + log_tbl->log); + } + + if (final_tbl_size < 0) { + pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n"); + ret = -EINVAL; + goto out_calc; + } + + memblock_reserve(efi.tpm_final_log, + final_tbl_size + sizeof(*final_tbl)); + efi_tpm_final_log_size = final_tbl_size; + +out_calc: + early_memunmap(final_tbl, sizeof(*final_tbl)); +out: + early_memunmap(log_tbl, sizeof(*log_tbl)); + return ret; +} + -- cgit v1.3.1