diff options
| -rw-r--r-- | include/linux/module.h | 4 | ||||
| -rw-r--r-- | include/linux/trace_events.h | 8 | ||||
| -rw-r--r-- | kernel/bpf/syscall.c | 11 | ||||
| -rw-r--r-- | kernel/module.c | 5 | ||||
| -rw-r--r-- | kernel/trace/bpf_trace.c | 99 |
5 files changed, 120 insertions, 7 deletions
diff --git a/include/linux/module.h b/include/linux/module.h index fce6b4335e36..5f147dd5e709 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -432,6 +432,10 @@ struct module { unsigned int num_tracepoints; tracepoint_ptr_t *tracepoints_ptrs; #endif +#ifdef CONFIG_BPF_EVENTS + unsigned int num_bpf_raw_events; + struct bpf_raw_event_map *bpf_raw_events; +#endif #ifdef HAVE_JUMP_LABEL struct jump_entry *jump_entries; unsigned int num_jump_entries; diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 4130a5497d40..8a62731673f7 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -471,7 +471,8 @@ void perf_event_detach_bpf_prog(struct perf_event *event); int perf_event_query_prog_array(struct perf_event *event, void __user *info); int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog); int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog); -struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name); +struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name); +void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp); int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, u32 *fd_type, const char **buf, u64 *probe_offset, u64 *probe_addr); @@ -502,10 +503,13 @@ static inline int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf { return -EOPNOTSUPP; } -static inline struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name) +static inline struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name) { return NULL; } +static inline void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) +{ +} static inline int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, u32 *fd_type, const char **buf, u64 *probe_offset, diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 5db31067d85e..0607db304def 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1604,6 +1604,7 @@ static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp) bpf_probe_unregister(raw_tp->btp, raw_tp->prog); bpf_prog_put(raw_tp->prog); } + bpf_put_raw_tracepoint(raw_tp->btp); kfree(raw_tp); return 0; } @@ -1629,13 +1630,15 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr) return -EFAULT; tp_name[sizeof(tp_name) - 1] = 0; - btp = bpf_find_raw_tracepoint(tp_name); + btp = bpf_get_raw_tracepoint(tp_name); if (!btp) return -ENOENT; raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER); - if (!raw_tp) - return -ENOMEM; + if (!raw_tp) { + err = -ENOMEM; + goto out_put_btp; + } raw_tp->btp = btp; prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd, @@ -1663,6 +1666,8 @@ out_put_prog: bpf_prog_put(prog); out_free_tp: kfree(raw_tp); +out_put_btp: + bpf_put_raw_tracepoint(btp); return err; } diff --git a/kernel/module.c b/kernel/module.c index 49a405891587..06ec68f08387 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3093,6 +3093,11 @@ static int find_module_sections(struct module *mod, struct load_info *info) sizeof(*mod->tracepoints_ptrs), &mod->num_tracepoints); #endif +#ifdef CONFIG_BPF_EVENTS + mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map", + sizeof(*mod->bpf_raw_events), + &mod->num_bpf_raw_events); +#endif #ifdef HAVE_JUMP_LABEL mod->jump_entries = section_objs(info, "__jump_table", sizeof(*mod->jump_entries), diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 9864a35c8bb5..9ddb6fddb4e0 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -17,6 +17,43 @@ #include "trace_probe.h" #include "trace.h" +#ifdef CONFIG_MODULES +struct bpf_trace_module { + struct module *module; + struct list_head list; +}; + +static LIST_HEAD(bpf_trace_modules); +static DEFINE_MUTEX(bpf_module_mutex); + +static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name) +{ + struct bpf_raw_event_map *btp, *ret = NULL; + struct bpf_trace_module *btm; + unsigned int i; + + mutex_lock(&bpf_module_mutex); + list_for_each_entry(btm, &bpf_trace_modules, list) { + for (i = 0; i < btm->module->num_bpf_raw_events; ++i) { + btp = &btm->module->bpf_raw_events[i]; + if (!strcmp(btp->tp->name, name)) { + if (try_module_get(btm->module)) + ret = btp; + goto out; + } + } + } +out: + mutex_unlock(&bpf_module_mutex); + return ret; +} +#else +static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name) +{ + return NULL; +} +#endif /* CONFIG_MODULES */ + u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); @@ -1076,7 +1113,7 @@ int perf_event_query_prog_array(struct perf_event *event, void __user *info) extern struct bpf_raw_event_map __start__bpf_raw_tp[]; extern struct bpf_raw_event_map __stop__bpf_raw_tp[]; -struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name) +struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name) { struct bpf_raw_event_map *btp = __start__bpf_raw_tp; @@ -1084,7 +1121,16 @@ struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name) if (!strcmp(btp->tp->name, name)) return btp; } - return NULL; + + return bpf_get_raw_tracepoint_module(name); +} + +void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) +{ + struct module *mod = __module_address((unsigned long)btp); + + if (mod) + module_put(mod); } static __always_inline @@ -1222,3 +1268,52 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, return err; } + +#ifdef CONFIG_MODULES +int bpf_event_notify(struct notifier_block *nb, unsigned long op, void *module) +{ + struct bpf_trace_module *btm, *tmp; + struct module *mod = module; + + if (mod->num_bpf_raw_events == 0 || + (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING)) + return 0; + + mutex_lock(&bpf_module_mutex); + + switch (op) { + case MODULE_STATE_COMING: + btm = kzalloc(sizeof(*btm), GFP_KERNEL); + if (btm) { + btm->module = module; + list_add(&btm->list, &bpf_trace_modules); + } + break; + case MODULE_STATE_GOING: + list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) { + if (btm->module == module) { + list_del(&btm->list); + kfree(btm); + break; + } + } + break; + } + + mutex_unlock(&bpf_module_mutex); + + return 0; +} + +static struct notifier_block bpf_module_nb = { + .notifier_call = bpf_event_notify, +}; + +int __init bpf_event_init(void) +{ + register_module_notifier(&bpf_module_nb); + return 0; +} + +fs_initcall(bpf_event_init); +#endif /* CONFIG_MODULES */ |