@@ -670,6 +670,21 @@ static int register_trace_kprobe(struct trace_kprobe *tk)
return ret;
}
+static int validate_module_probe_symbol(const char *modname, const char *symbol);
+
+static int register_module_trace_kprobe(struct module *mod, struct trace_kprobe *tk)
+{
+ const char *p;
+ int ret = 0;
+
+ p = strchr(trace_kprobe_symbol(tk), ':');
+ if (p)
+ ret = validate_module_probe_symbol(module_name(mod), p + 1);
+ if (!ret)
+ ret = __register_trace_kprobe(tk);
+ return ret;
+}
+
/* Module notifier call back, checking event on the module */
static int trace_kprobe_module_callback(struct notifier_block *nb,
unsigned long val, void *data)
@@ -688,7 +703,7 @@ static int trace_kprobe_module_callback(struct notifier_block *nb,
if (trace_kprobe_within_module(tk, mod)) {
/* Don't need to check busy - this should have gone. */
__unregister_trace_kprobe(tk);
- ret = __register_trace_kprobe(tk);
+ ret = register_module_trace_kprobe(mod, tk);
if (ret)
pr_warn("Failed to re-register probe %s on %s: %d\n",
trace_probe_name(&tk->tp),
@@ -729,17 +744,68 @@ static int count_mod_symbols(void *data, const char *name, unsigned long unused)
return 0;
}
-static unsigned int number_of_same_symbols(char *func_name)
+static unsigned int number_of_same_symbols(const char *mod, const char *func_name)
{
struct sym_count_ctx ctx = { .count = 0, .name = func_name };
- kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
+ if (!mod)
+ kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
- module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx);
+ module_kallsyms_on_each_symbol(mod, count_mod_symbols, &ctx);
return ctx.count;
}
+static int validate_module_probe_symbol(const char *modname, const char *symbol)
+{
+ unsigned int count = number_of_same_symbols(modname, symbol);
+
+ if (count > 1) {
+ /*
+ * Users should use ADDR to remove the ambiguity of
+ * using KSYM only.
+ */
+ return -EADDRNOTAVAIL;
+ } else if (count == 0) {
+ /*
+ * We can return ENOENT earlier than when register the
+ * kprobe.
+ */
+ return -ENOENT;
+ }
+ return 0;
+}
+
+static int validate_probe_symbol(char *symbol)
+{
+ struct module *mod = NULL;
+ char *modname = NULL, *p;
+ int ret = 0;
+
+ p = strchr(symbol, ':');
+ if (p) {
+ modname = symbol;
+ symbol = p + 1;
+ *p = '\0';
+ /* Return 0 (defer) if the module does not exist yet. */
+ rcu_read_lock_sched();
+ mod = find_module(modname);
+ if (mod && !try_module_get(mod))
+ mod = NULL;
+ rcu_read_unlock_sched();
+ if (!mod)
+ goto out;
+ }
+
+ ret = validate_module_probe_symbol(modname, symbol);
+out:
+ if (p)
+ *p = ':';
+ if (mod)
+ module_put(mod);
+ return ret;
+}
+
static int trace_kprobe_entry_handler(struct kretprobe_instance *ri,
struct pt_regs *regs);
@@ -863,6 +929,14 @@ static int __trace_kprobe_create(int argc, const char *argv[])
trace_probe_log_err(0, BAD_PROBE_ADDR);
goto parse_error;
}
+ ret = validate_probe_symbol(symbol);
+ if (ret) {
+ if (ret == -EADDRNOTAVAIL)
+ trace_probe_log_err(0, NON_UNIQ_SYMBOL);
+ else
+ trace_probe_log_err(0, BAD_PROBE_ADDR);
+ goto parse_error;
+ }
if (is_return)
ctx.flags |= TPARG_FL_RETURN;
ret = kprobe_on_func_entry(NULL, symbol, offset);
@@ -875,31 +949,6 @@ 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, gbuf,
@@ -1817,21 +1866,9 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
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);
+ ret = validate_probe_symbol(func);
+ if (ret)
+ return ERR_PTR(ret);
}
/*