From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- lib/error-inject.c | 239 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 239 insertions(+) create mode 100644 lib/error-inject.c (limited to 'lib/error-inject.c') diff --git a/lib/error-inject.c b/lib/error-inject.c new file mode 100644 index 000000000..32f3d1ca9 --- /dev/null +++ b/lib/error-inject.c @@ -0,0 +1,239 @@ +// SPDX-License-Identifier: GPL-2.0 +// error-inject.c: Function-level error injection table +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Whitelist of symbols that can be overridden for error injection. */ +static LIST_HEAD(error_injection_list); +static DEFINE_MUTEX(ei_mutex); +struct ei_entry { + struct list_head list; + unsigned long start_addr; + unsigned long end_addr; + int etype; + void *priv; +}; + +bool within_error_injection_list(unsigned long addr) +{ + struct ei_entry *ent; + bool ret = false; + + mutex_lock(&ei_mutex); + list_for_each_entry(ent, &error_injection_list, list) { + if (addr >= ent->start_addr && addr < ent->end_addr) { + ret = true; + break; + } + } + mutex_unlock(&ei_mutex); + return ret; +} + +int get_injectable_error_type(unsigned long addr) +{ + struct ei_entry *ent; + int ei_type = -EINVAL; + + mutex_lock(&ei_mutex); + list_for_each_entry(ent, &error_injection_list, list) { + if (addr >= ent->start_addr && addr < ent->end_addr) { + ei_type = ent->etype; + break; + } + } + mutex_unlock(&ei_mutex); + + return ei_type; +} + +/* + * Lookup and populate the error_injection_list. + * + * For safety reasons we only allow certain functions to be overridden with + * bpf_error_injection, so we need to populate the list of the symbols that have + * been marked as safe for overriding. + */ +static void populate_error_injection_list(struct error_injection_entry *start, + struct error_injection_entry *end, + void *priv) +{ + struct error_injection_entry *iter; + struct ei_entry *ent; + unsigned long entry, offset = 0, size = 0; + + mutex_lock(&ei_mutex); + for (iter = start; iter < end; iter++) { + entry = (unsigned long)dereference_symbol_descriptor((void *)iter->addr); + + if (!kernel_text_address(entry) || + !kallsyms_lookup_size_offset(entry, &size, &offset)) { + pr_err("Failed to find error inject entry at %p\n", + (void *)entry); + continue; + } + + ent = kmalloc_obj(*ent); + if (!ent) + break; + ent->start_addr = entry; + ent->end_addr = entry + size; + ent->etype = iter->etype; + ent->priv = priv; + INIT_LIST_HEAD(&ent->list); + list_add_tail(&ent->list, &error_injection_list); + } + mutex_unlock(&ei_mutex); +} + +/* Markers of the _error_inject_whitelist section */ +extern struct error_injection_entry __start_error_injection_whitelist[]; +extern struct error_injection_entry __stop_error_injection_whitelist[]; + +static void __init populate_kernel_ei_list(void) +{ + populate_error_injection_list(__start_error_injection_whitelist, + __stop_error_injection_whitelist, + NULL); +} + +#ifdef CONFIG_MODULES +static void module_load_ei_list(struct module *mod) +{ + if (!mod->num_ei_funcs) + return; + + populate_error_injection_list(mod->ei_funcs, + mod->ei_funcs + mod->num_ei_funcs, mod); +} + +static void module_unload_ei_list(struct module *mod) +{ + struct ei_entry *ent, *n; + + if (!mod->num_ei_funcs) + return; + + mutex_lock(&ei_mutex); + list_for_each_entry_safe(ent, n, &error_injection_list, list) { + if (ent->priv == mod) { + list_del_init(&ent->list); + kfree(ent); + } + } + mutex_unlock(&ei_mutex); +} + +/* Module notifier call back, checking error injection table on the module */ +static int ei_module_callback(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct module *mod = data; + + if (val == MODULE_STATE_COMING) + module_load_ei_list(mod); + else if (val == MODULE_STATE_GOING) + module_unload_ei_list(mod); + + return NOTIFY_DONE; +} + +static struct notifier_block ei_module_nb = { + .notifier_call = ei_module_callback, + .priority = 0 +}; + +static __init int module_ei_init(void) +{ + return register_module_notifier(&ei_module_nb); +} +#else /* !CONFIG_MODULES */ +#define module_ei_init() (0) +#endif + +/* + * error_injection/whitelist -- shows which functions can be overridden for + * error injection. + */ +static void *ei_seq_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&ei_mutex); + return seq_list_start(&error_injection_list, *pos); +} + +static void ei_seq_stop(struct seq_file *m, void *v) +{ + mutex_unlock(&ei_mutex); +} + +static void *ei_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return seq_list_next(v, &error_injection_list, pos); +} + +static const char *error_type_string(int etype) +{ + switch (etype) { + case EI_ETYPE_NULL: + return "NULL"; + case EI_ETYPE_ERRNO: + return "ERRNO"; + case EI_ETYPE_ERRNO_NULL: + return "ERRNO_NULL"; + case EI_ETYPE_TRUE: + return "TRUE"; + default: + return "(unknown)"; + } +} + +static int ei_seq_show(struct seq_file *m, void *v) +{ + struct ei_entry *ent = list_entry(v, struct ei_entry, list); + + seq_printf(m, "%ps\t%s\n", (void *)ent->start_addr, + error_type_string(ent->etype)); + return 0; +} + +static const struct seq_operations ei_sops = { + .start = ei_seq_start, + .next = ei_seq_next, + .stop = ei_seq_stop, + .show = ei_seq_show, +}; + +DEFINE_SEQ_ATTRIBUTE(ei); + +static int __init ei_debugfs_init(void) +{ + struct dentry *dir, *file; + + dir = debugfs_create_dir("error_injection", NULL); + + file = debugfs_create_file("list", 0444, dir, NULL, &ei_fops); + if (IS_ERR(file)) { + debugfs_remove(dir); + return PTR_ERR(file); + } + + return 0; +} + +static int __init init_error_injection(void) +{ + populate_kernel_ei_list(); + + if (!module_ei_init()) + ei_debugfs_init(); + + return 0; +} +late_initcall(init_error_injection); -- cgit v1.3.1