diff options
Diffstat (limited to 'kernel/trace/trace_kprobe.c')
-rw-r--r-- | kernel/trace/trace_kprobe.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 0b3ee4eea51b..1c565db2de7b 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -708,6 +708,36 @@ static struct notifier_block trace_kprobe_module_nb = { .priority = 1 /* Invoked after kprobe module callback */ }; +struct count_symbols_struct { + const char *func_name; + unsigned int count; +}; + +static int count_symbols(void *data, const char *name, struct module *unused0, + unsigned long unused1) +{ + struct count_symbols_struct *args = data; + + if (strcmp(args->func_name, name)) + return 0; + + args->count++; + + return 0; +} + +static unsigned int number_of_same_symbols(char *func_name) +{ + struct count_symbols_struct args = { + .func_name = func_name, + .count = 0, + }; + + kallsyms_on_each_symbol(count_symbols, &args); + + return args.count; +} + static int __trace_kprobe_create(int argc, const char *argv[]) { /* @@ -836,6 +866,31 @@ static int __trace_kprobe_create(int argc, const char *argv[]) } } + if (symbol && !strchr(symbol, ':')) { + unsigned int count; + + count = number_of_same_symbols(symbol); + if (count > 1) { + /* + * Users should use ADDR to remove the ambiguity of + * using KSYM only. + */ + trace_probe_log_err(0, NON_UNIQ_SYMBOL); + ret = -EADDRNOTAVAIL; + + goto error; + } else if (count == 0) { + /* + * We can return ENOENT earlier than when register the + * kprobe. + */ + trace_probe_log_err(0, BAD_PROBE_ADDR); + ret = -ENOENT; + + goto error; + } + } + trace_probe_log_set_index(0); if (event) { ret = traceprobe_parse_event_name(&event, &group, buf, @@ -1755,6 +1810,7 @@ static int unregister_kprobe_event(struct trace_kprobe *tk) } #ifdef CONFIG_PERF_EVENTS + /* create a trace_kprobe, but don't add it to global lists */ struct trace_event_call * create_local_trace_kprobe(char *func, void *addr, unsigned long offs, @@ -1765,6 +1821,24 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs, int ret; char *event; + if (func) { + unsigned int count; + + count = number_of_same_symbols(func); + if (count > 1) + /* + * Users should use addr to remove the ambiguity of + * using func only. + */ + return ERR_PTR(-EADDRNOTAVAIL); + else if (count == 0) + /* + * We can return ENOENT earlier than when register the + * kprobe. + */ + return ERR_PTR(-ENOENT); + } + /* * local trace_kprobes are not added to dyn_event, so they are never * searched in find_trace_kprobe(). Therefore, there is no concern of |