diff --git a/arch/Kconfig b/arch/Kconfig index 472c8d0d7129..fdbea7afd861 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -199,7 +199,7 @@ config HAVE_OPTPROBES config HAVE_KPROBES_ON_FTRACE bool -config HAVE_KPROBE_OVERRIDE +config HAVE_FUNCTION_ERROR_INJECTION bool config HAVE_NMI diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 36909efb9f16..be4b40d5d887 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -155,7 +155,7 @@ config X86 select HAVE_KERNEL_XZ select HAVE_KPROBES select HAVE_KPROBES_ON_FTRACE - select HAVE_KPROBE_OVERRIDE + select HAVE_FUNCTION_ERROR_INJECTION select HAVE_KRETPROBES select HAVE_KVM select HAVE_LIVEPATCH if X86_64 diff --git a/arch/x86/include/asm/error-injection.h b/arch/x86/include/asm/error-injection.h new file mode 100644 index 000000000000..47b7a1296245 --- /dev/null +++ b/arch/x86/include/asm/error-injection.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_ERROR_INJECTION_H +#define _ASM_ERROR_INJECTION_H + +#include +#include +#include +#include + +asmlinkage void just_return_func(void); +void override_function_with_return(struct pt_regs *regs); + +#endif /* _ASM_ERROR_INJECTION_H */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index 60b410ff31e8..55f70309be9c 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -38,6 +38,7 @@ lib-y += memcpy_$(BITS).o lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o +lib-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o lib-$(CONFIG_RETPOLINE) += retpoline.o obj-y += msr.o msr-reg.o msr-reg-export.o hweight.o diff --git a/arch/x86/lib/error-inject.c b/arch/x86/lib/error-inject.c new file mode 100644 index 000000000000..7b881d03d0dd --- /dev/null +++ b/arch/x86/lib/error-inject.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include + +asmlinkage void just_return_func(void); + +asm( + ".type just_return_func, @function\n" + "just_return_func:\n" + " ret\n" + ".size just_return_func, .-just_return_func\n" +); + +void override_function_with_return(struct pt_regs *regs) +{ + regs->ip = (unsigned long)&just_return_func; +} +NOKPROBE_SYMBOL(override_function_with_return); diff --git a/include/asm-generic/error-injection.h b/include/asm-generic/error-injection.h new file mode 100644 index 000000000000..08352c9d9f97 --- /dev/null +++ b/include/asm-generic/error-injection.h @@ -0,0 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_ERROR_INJECTION_H +#define _ASM_GENERIC_ERROR_INJECTION_H + +#if defined(__KERNEL__) && !defined(__ASSEMBLY__) +#ifdef CONFIG_FUNCTION_ERROR_INJECTION +/* + * Whitelist ganerating macro. Specify functions which can be + * error-injectable using this macro. + */ +#define ALLOW_ERROR_INJECTION(fname) \ +static unsigned long __used \ + __attribute__((__section__("_error_injection_whitelist"))) \ + _eil_addr_##fname = (unsigned long)fname; +#else +#define ALLOW_ERROR_INJECTION(fname) +#endif +#endif + +#endif /* _ASM_GENERIC_ERROR_INJECTION_H */ diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 2aecaf93693b..f0e4aa59307c 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -147,13 +147,13 @@ #define KPROBE_BLACKLIST() #endif -#ifdef CONFIG_BPF_KPROBE_OVERRIDE -#define ERROR_INJECT_LIST() . = ALIGN(8); \ - VMLINUX_SYMBOL(__start_kprobe_error_inject_list) = .; \ - KEEP(*(_kprobe_error_inject_list)) \ - VMLINUX_SYMBOL(__stop_kprobe_error_inject_list) = .; +#ifdef CONFIG_FUNCTION_ERROR_INJECTION +#define ERROR_INJECT_WHITELIST() . = ALIGN(8); \ + VMLINUX_SYMBOL(__start_error_injection_whitelist) = .;\ + KEEP(*(_error_injection_whitelist)) \ + VMLINUX_SYMBOL(__stop_error_injection_whitelist) = .; #else -#define ERROR_INJECT_LIST() +#define ERROR_INJECT_WHITELIST() #endif #ifdef CONFIG_EVENT_TRACING @@ -588,7 +588,7 @@ FTRACE_EVENTS() \ TRACE_SYSCALLS() \ KPROBE_BLACKLIST() \ - ERROR_INJECT_LIST() \ + ERROR_INJECT_WHITELIST() \ MEM_DISCARD(init.rodata) \ CLK_OF_TABLES() \ RESERVEDMEM_OF_TABLES() \ diff --git a/include/linux/bpf.h b/include/linux/bpf.h index aa5829f0ae50..d45744731bff 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -631,15 +631,4 @@ extern const struct bpf_func_proto bpf_sock_map_update_proto; void bpf_user_rnd_init_once(void); u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); -#if defined(__KERNEL__) && !defined(__ASSEMBLY__) -#ifdef CONFIG_BPF_KPROBE_OVERRIDE -#define BPF_ALLOW_ERROR_INJECTION(fname) \ -static unsigned long __used \ - __attribute__((__section__("_kprobe_error_inject_list"))) \ - _eil_addr_##fname = (unsigned long)fname; -#else -#define BPF_ALLOW_ERROR_INJECTION(fname) -#endif -#endif - #endif /* _LINUX_BPF_H */ diff --git a/include/linux/error-injection.h b/include/linux/error-injection.h new file mode 100644 index 000000000000..130a67c50dac --- /dev/null +++ b/include/linux/error-injection.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_ERROR_INJECTION_H +#define _LINUX_ERROR_INJECTION_H + +#ifdef CONFIG_FUNCTION_ERROR_INJECTION + +#include + +extern bool within_error_injection_list(unsigned long addr); + +#else /* !CONFIG_FUNCTION_ERROR_INJECTION */ + +#include +static inline bool within_error_injection_list(unsigned long addr) +{ + return false; +} + +#endif + +#endif /* _LINUX_ERROR_INJECTION_H */ diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 9b6ece57cfff..a3b380899e5d 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -274,7 +274,6 @@ extern bool arch_kprobe_on_func_entry(unsigned long offset); extern bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset); extern bool within_kprobe_blacklist(unsigned long addr); -extern bool within_kprobe_error_injection_list(unsigned long addr); struct kprobe_insn_cache { struct mutex mutex; diff --git a/include/linux/module.h b/include/linux/module.h index 72c25f845fbe..49176730b851 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -482,9 +482,9 @@ struct module { unsigned int num_ctors; #endif -#ifdef CONFIG_BPF_KPROBE_OVERRIDE - unsigned int num_kprobe_ei_funcs; - unsigned long *kprobe_ei_funcs; +#ifdef CONFIG_FUNCTION_ERROR_INJECTION + unsigned int num_ei_funcs; + unsigned long *ei_funcs; #endif } ____cacheline_aligned __randomize_layout; #ifndef MODULE_ARCH_INIT diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 6232ea3ce94f..e86bbcb849ac 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -83,16 +83,6 @@ static raw_spinlock_t *kretprobe_table_lock_ptr(unsigned long hash) return &(kretprobe_table_locks[hash].lock); } -/* List of symbols that can be overriden for error injection. */ -static LIST_HEAD(kprobe_error_injection_list); -static DEFINE_MUTEX(kprobe_ei_mutex); -struct kprobe_ei_entry { - struct list_head list; - unsigned long start_addr; - unsigned long end_addr; - void *priv; -}; - /* Blacklist -- list of struct kprobe_blacklist_entry */ static LIST_HEAD(kprobe_blacklist); @@ -1467,17 +1457,6 @@ bool within_kprobe_blacklist(unsigned long addr) return false; } -bool within_kprobe_error_injection_list(unsigned long addr) -{ - struct kprobe_ei_entry *ent; - - list_for_each_entry(ent, &kprobe_error_injection_list, list) { - if (addr >= ent->start_addr && addr < ent->end_addr) - return true; - } - return false; -} - /* * If we have a symbol_name argument, look it up and add the offset field * to it. This way, we can specify a relative address to a symbol. @@ -2279,86 +2258,6 @@ static int __init populate_kprobe_blacklist(unsigned long *start, return 0; } -#ifdef CONFIG_BPF_KPROBE_OVERRIDE -/* Markers of the _kprobe_error_inject_list section */ -extern unsigned long __start_kprobe_error_inject_list[]; -extern unsigned long __stop_kprobe_error_inject_list[]; - -/* - * Lookup and populate the kprobe_error_injection_list. - * - * For safety reasons we only allow certain functions to be overriden 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_kprobe_error_injection_list(unsigned long *start, - unsigned long *end, - void *priv) -{ - unsigned long *iter; - struct kprobe_ei_entry *ent; - unsigned long entry, offset = 0, size = 0; - - mutex_lock(&kprobe_ei_mutex); - for (iter = start; iter < end; iter++) { - entry = arch_deref_entry_point((void *)*iter); - - 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(sizeof(*ent), GFP_KERNEL); - if (!ent) - break; - ent->start_addr = entry; - ent->end_addr = entry + size; - ent->priv = priv; - INIT_LIST_HEAD(&ent->list); - list_add_tail(&ent->list, &kprobe_error_injection_list); - } - mutex_unlock(&kprobe_ei_mutex); -} - -static void __init populate_kernel_kprobe_ei_list(void) -{ - populate_kprobe_error_injection_list(__start_kprobe_error_inject_list, - __stop_kprobe_error_inject_list, - NULL); -} - -static void module_load_kprobe_ei_list(struct module *mod) -{ - if (!mod->num_kprobe_ei_funcs) - return; - populate_kprobe_error_injection_list(mod->kprobe_ei_funcs, - mod->kprobe_ei_funcs + - mod->num_kprobe_ei_funcs, mod); -} - -static void module_unload_kprobe_ei_list(struct module *mod) -{ - struct kprobe_ei_entry *ent, *n; - if (!mod->num_kprobe_ei_funcs) - return; - - mutex_lock(&kprobe_ei_mutex); - list_for_each_entry_safe(ent, n, &kprobe_error_injection_list, list) { - if (ent->priv == mod) { - list_del_init(&ent->list); - kfree(ent); - } - } - mutex_unlock(&kprobe_ei_mutex); -} -#else -static inline void __init populate_kernel_kprobe_ei_list(void) {} -static inline void module_load_kprobe_ei_list(struct module *m) {} -static inline void module_unload_kprobe_ei_list(struct module *m) {} -#endif - /* Module notifier call back, checking kprobes on the module */ static int kprobes_module_callback(struct notifier_block *nb, unsigned long val, void *data) @@ -2369,11 +2268,6 @@ static int kprobes_module_callback(struct notifier_block *nb, unsigned int i; int checkcore = (val == MODULE_STATE_GOING); - if (val == MODULE_STATE_COMING) - module_load_kprobe_ei_list(mod); - else if (val == MODULE_STATE_GOING) - module_unload_kprobe_ei_list(mod); - if (val != MODULE_STATE_GOING && val != MODULE_STATE_LIVE) return NOTIFY_DONE; @@ -2440,8 +2334,6 @@ static int __init init_kprobes(void) pr_err("Please take care of using kprobes.\n"); } - populate_kernel_kprobe_ei_list(); - if (kretprobe_blacklist_size) { /* lookup the function address from its name */ for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { @@ -2609,56 +2501,6 @@ static const struct file_operations debugfs_kprobe_blacklist_ops = { .release = seq_release, }; -/* - * kprobes/error_injection_list -- shows which functions can be overriden for - * error injection. - * */ -static void *kprobe_ei_seq_start(struct seq_file *m, loff_t *pos) -{ - mutex_lock(&kprobe_ei_mutex); - return seq_list_start(&kprobe_error_injection_list, *pos); -} - -static void kprobe_ei_seq_stop(struct seq_file *m, void *v) -{ - mutex_unlock(&kprobe_ei_mutex); -} - -static void *kprobe_ei_seq_next(struct seq_file *m, void *v, loff_t *pos) -{ - return seq_list_next(v, &kprobe_error_injection_list, pos); -} - -static int kprobe_ei_seq_show(struct seq_file *m, void *v) -{ - char buffer[KSYM_SYMBOL_LEN]; - struct kprobe_ei_entry *ent = - list_entry(v, struct kprobe_ei_entry, list); - - sprint_symbol(buffer, ent->start_addr); - seq_printf(m, "%s\n", buffer); - return 0; -} - -static const struct seq_operations kprobe_ei_seq_ops = { - .start = kprobe_ei_seq_start, - .next = kprobe_ei_seq_next, - .stop = kprobe_ei_seq_stop, - .show = kprobe_ei_seq_show, -}; - -static int kprobe_ei_open(struct inode *inode, struct file *filp) -{ - return seq_open(filp, &kprobe_ei_seq_ops); -} - -static const struct file_operations debugfs_kprobe_ei_ops = { - .open = kprobe_ei_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_release, -}; - static void arm_all_kprobes(void) { struct hlist_head *head; @@ -2800,11 +2642,6 @@ static int __init debugfs_kprobe_init(void) if (!file) goto error; - file = debugfs_create_file("error_injection_list", 0444, dir, NULL, - &debugfs_kprobe_ei_ops); - if (!file) - goto error; - return 0; error: diff --git a/kernel/module.c b/kernel/module.c index 9427691b76b0..2c758feac055 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3200,10 +3200,10 @@ static int find_module_sections(struct module *mod, struct load_info *info) sizeof(*mod->ftrace_callsites), &mod->num_ftrace_callsites); #endif -#ifdef CONFIG_BPF_KPROBE_OVERRIDE - mod->kprobe_ei_funcs = section_objs(info, "_kprobe_error_inject_list", - sizeof(*mod->kprobe_ei_funcs), - &mod->num_kprobe_ei_funcs); +#ifdef CONFIG_FUNCTION_ERROR_INJECTION + mod->ei_funcs = section_objs(info, "_error_injection_whitelist", + sizeof(*mod->ei_funcs), + &mod->num_ei_funcs); #endif mod->extable = section_objs(info, "__ex_table", sizeof(*mod->extable), &mod->num_exentries); diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 991bec51c3ff..a1ad69156638 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -536,7 +536,7 @@ config BPF_KPROBE_OVERRIDE bool "Enable BPF programs to override a kprobed function" depends on BPF_EVENTS depends on KPROBES_ON_FTRACE - depends on HAVE_KPROBE_OVERRIDE + depends on FUNCTION_ERROR_INJECTION depends on DYNAMIC_FTRACE_WITH_REGS default n help diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 6d168738def2..0ed7f7fa7b39 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -14,7 +14,7 @@ #include #include #include -#include +#include #include "trace_probe.h" #include "trace.h" @@ -85,7 +85,7 @@ BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc) { __this_cpu_write(bpf_kprobe_override, 1); regs_set_return_value(regs, rc); - arch_ftrace_kprobe_override_function(regs); + override_function_with_return(regs); return 0; } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 5e36563d6848..02446060aa7d 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "trace_probe.h" @@ -106,7 +107,7 @@ int trace_kprobe_error_injectable(struct trace_event_call *call) } else { addr = (unsigned long)tk->rp.kp.addr; } - return within_kprobe_error_injection_list(addr); + return within_error_injection_list(addr); } static int register_kprobe_event(struct trace_kprobe *tk); diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 0073b9458b46..673a651c82f0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1520,6 +1520,10 @@ config FAULT_INJECTION Provide fault-injection framework. For more details, see Documentation/fault-injection/. +config FUNCTION_ERROR_INJECTION + def_bool y + depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES + config FAILSLAB bool "Fault-injection capability for kmalloc" depends on FAULT_INJECTION diff --git a/lib/Makefile b/lib/Makefile index a7e6dcedb732..26fd0bf17682 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -164,6 +164,7 @@ obj-$(CONFIG_NETDEV_NOTIFIER_ERROR_INJECT) += netdev-notifier-error-inject.o obj-$(CONFIG_MEMORY_NOTIFIER_ERROR_INJECT) += memory-notifier-error-inject.o obj-$(CONFIG_OF_RECONFIG_NOTIFIER_ERROR_INJECT) += \ of-reconfig-notifier-error-inject.o +obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o lib-$(CONFIG_GENERIC_BUG) += bug.o diff --git a/lib/error-inject.c b/lib/error-inject.c new file mode 100644 index 000000000000..bccadcf3c981 --- /dev/null +++ b/lib/error-inject.c @@ -0,0 +1,213 @@ +// SPDX-License-Identifier: GPL-2.0 +// error-inject.c: Function-level error injection table +#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; + 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; +} + +/* + * 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(unsigned long *start, + unsigned long *end, void *priv) +{ + unsigned long *iter; + struct ei_entry *ent; + unsigned long entry, offset = 0, size = 0; + + mutex_lock(&ei_mutex); + for (iter = start; iter < end; iter++) { + entry = arch_deref_entry_point((void *)*iter); + + 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(sizeof(*ent), GFP_KERNEL); + if (!ent) + break; + ent->start_addr = entry; + ent->end_addr = entry + size; + 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 unsigned long __start_error_injection_whitelist[]; +extern unsigned long __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 int ei_seq_show(struct seq_file *m, void *v) +{ + struct ei_entry *ent = list_entry(v, struct ei_entry, list); + + seq_printf(m, "%pf\n", (void *)ent->start_addr); + return 0; +} + +static const struct seq_operations ei_seq_ops = { + .start = ei_seq_start, + .next = ei_seq_next, + .stop = ei_seq_stop, + .show = ei_seq_show, +}; + +static int ei_open(struct inode *inode, struct file *filp) +{ + return seq_open(filp, &ei_seq_ops); +} + +static const struct file_operations debugfs_ei_ops = { + .open = ei_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init ei_debugfs_init(void) +{ + struct dentry *dir, *file; + + dir = debugfs_create_dir("error_injection", NULL); + if (!dir) + return -ENOMEM; + + file = debugfs_create_file("list", 0444, dir, NULL, &debugfs_ei_ops); + if (!file) { + debugfs_remove(dir); + return -ENOMEM; + } + + 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);