diff options
Diffstat (limited to 'kernel/trace/trace_fprobe.c')
| -rw-r--r-- | kernel/trace/trace_fprobe.c | 59 |
1 files changed, 44 insertions, 15 deletions
diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index b8f3c4ba309b..b40fa59159ac 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -919,14 +919,15 @@ static void __find_tracepoint_module_cb(struct tracepoint *tp, struct module *mo struct __find_tracepoint_cb_data *data = priv; if (!data->tpoint && !strcmp(data->tp_name, tp->name)) { - data->tpoint = tp; - if (!data->mod) { + /* If module is not specified, try getting module refcount. */ + if (!data->mod && mod) { + /* If failed to get refcount, ignore this tracepoint. */ + if (!try_module_get(mod)) + return; + data->mod = mod; - if (!try_module_get(data->mod)) { - data->tpoint = NULL; - data->mod = NULL; - } } + data->tpoint = tp; } } @@ -939,11 +940,9 @@ static void __find_tracepoint_cb(struct tracepoint *tp, void *priv) } /* - * Find a tracepoint from kernel and module. If the tracepoint is in a module, - * this increments the module refcount to prevent unloading until the - * trace_fprobe is registered to the list. After registering the trace_fprobe - * on the trace_fprobe list, the module refcount is decremented because - * tracepoint_probe_module_cb will handle it. + * Find a tracepoint from kernel and module. If the tracepoint is on the module, + * the module's refcount is incremented and returned as *@tp_mod. Thus, if it is + * not NULL, caller must call module_put(*tp_mod) after used the tracepoint. */ static struct tracepoint *find_tracepoint(const char *tp_name, struct module **tp_mod) @@ -973,6 +972,10 @@ static void reenable_trace_fprobe(struct trace_fprobe *tf) } } +/* + * Find a tracepoint from specified module. In this case, this does not get the + * module's refcount. The caller must ensure the module is not freed. + */ static struct tracepoint *find_tracepoint_in_module(struct module *mod, const char *tp_name) { @@ -1008,10 +1011,13 @@ static int __tracepoint_probe_module_cb(struct notifier_block *self, reenable_trace_fprobe(tf); } } else if (val == MODULE_STATE_GOING && tp_mod->mod == tf->mod) { - tracepoint_probe_unregister(tf->tpoint, + unregister_fprobe(&tf->fp); + if (trace_fprobe_is_tracepoint(tf)) { + tracepoint_probe_unregister(tf->tpoint, tf->tpoint->probestub, NULL); - tf->tpoint = NULL; - tf->mod = NULL; + tf->tpoint = TRACEPOINT_STUB; + tf->mod = NULL; + } } } mutex_unlock(&event_mutex); @@ -1049,6 +1055,19 @@ static int parse_symbol_and_return(int argc, const char *argv[], if (*is_return) return 0; + if (is_tracepoint) { + tmp = *symbol; + while (*tmp && (isalnum(*tmp) || *tmp == '_')) + tmp++; + if (*tmp) { + /* find a wrong character. */ + trace_probe_log_err(tmp - *symbol, BAD_TP_NAME); + kfree(*symbol); + *symbol = NULL; + return -EINVAL; + } + } + /* If there is $retval, this should be a return fprobe. */ for (i = 2; i < argc; i++) { tmp = strstr(argv[i], "$retval"); @@ -1056,6 +1075,8 @@ static int parse_symbol_and_return(int argc, const char *argv[], if (is_tracepoint) { trace_probe_log_set_index(i); trace_probe_log_err(tmp - argv[i], RETVAL_ON_PROBE); + kfree(*symbol); + *symbol = NULL; return -EINVAL; } *is_return = true; @@ -1186,8 +1207,11 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], argc = new_argc; argv = new_argv; } - if (argc > MAX_TRACE_ARGS) + if (argc > MAX_TRACE_ARGS) { + trace_probe_log_set_index(2); + trace_probe_log_err(0, TOO_MANY_ARGS); return -E2BIG; + } ret = traceprobe_expand_dentry_args(argc, argv, &dbuf); if (ret) @@ -1215,6 +1239,11 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], if (is_return && tf->tp.entry_arg) { tf->fp.entry_handler = trace_fprobe_entry_handler; tf->fp.entry_data_size = traceprobe_get_entry_data_size(&tf->tp); + if (ALIGN(tf->fp.entry_data_size, sizeof(long)) > MAX_FPROBE_DATA_SIZE) { + trace_probe_log_set_index(2); + trace_probe_log_err(0, TOO_MANY_EARGS); + return -E2BIG; + } } ret = traceprobe_set_print_fmt(&tf->tp, |