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Diffstat (limited to 'kernel/trace/trace_kprobe.c')
-rw-r--r--kernel/trace/trace_kprobe.c192
1 files changed, 111 insertions, 81 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 16383247bdbf..61a6da808203 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -678,6 +678,21 @@ end:
}
#ifdef CONFIG_MODULES
+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)
@@ -696,7 +711,7 @@ 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),
@@ -747,17 +762,81 @@ 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;
+}
+
+#ifdef CONFIG_MODULES
+/* Return NULL if the module is not loaded or under unloading. */
+static struct module *try_module_get_by_name(const char *name)
+{
+ struct module *mod;
+
+ rcu_read_lock_sched();
+ mod = find_module(name);
+ if (mod && !try_module_get(mod))
+ mod = NULL;
+ rcu_read_unlock_sched();
+
+ return mod;
+}
+#else
+#define try_module_get_by_name(name) (NULL)
+#endif
+
+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';
+ mod = try_module_get_by_name(modname);
+ 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);
@@ -881,6 +960,14 @@ 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);
@@ -893,31 +980,6 @@ 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,
@@ -1835,21 +1897,9 @@ 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);
}
/*
@@ -2023,19 +2073,16 @@ static __init int kprobe_trace_self_tests_init(void)
pr_info("Testing kprobe tracing: ");
ret = create_or_delete_trace_kprobe("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)");
- if (WARN_ON_ONCE(ret)) {
- pr_warn("error on probing function entry.\n");
+ if (WARN_ONCE(ret, "error on probing function entry.")) {
warn++;
} else {
/* Enable trace point */
tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
- if (WARN_ON_ONCE(tk == NULL)) {
- pr_warn("error on getting new probe.\n");
+ if (WARN_ONCE(tk == NULL, "error on probing function entry.")) {
warn++;
} else {
file = find_trace_probe_file(tk, top_trace_array());
- if (WARN_ON_ONCE(file == NULL)) {
- pr_warn("error on getting probe file.\n");
+ if (WARN_ONCE(file == NULL, "error on getting probe file.")) {
warn++;
} else
enable_trace_kprobe(
@@ -2044,19 +2091,16 @@ static __init int kprobe_trace_self_tests_init(void)
}
ret = create_or_delete_trace_kprobe("r:testprobe2 kprobe_trace_selftest_target $retval");
- if (WARN_ON_ONCE(ret)) {
- pr_warn("error on probing function return.\n");
+ if (WARN_ONCE(ret, "error on probing function return.")) {
warn++;
} else {
/* Enable trace point */
tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
- if (WARN_ON_ONCE(tk == NULL)) {
- pr_warn("error on getting 2nd new probe.\n");
+ if (WARN_ONCE(tk == NULL, "error on getting 2nd new probe.")) {
warn++;
} else {
file = find_trace_probe_file(tk, top_trace_array());
- if (WARN_ON_ONCE(file == NULL)) {
- pr_warn("error on getting probe file.\n");
+ if (WARN_ONCE(file == NULL, "error on getting probe file.")) {
warn++;
} else
enable_trace_kprobe(
@@ -2079,18 +2123,15 @@ static __init int kprobe_trace_self_tests_init(void)
/* Disable trace points before removing it */
tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
- if (WARN_ON_ONCE(tk == NULL)) {
- pr_warn("error on getting test probe.\n");
+ if (WARN_ONCE(tk == NULL, "error on getting test probe.")) {
warn++;
} else {
- if (trace_kprobe_nhit(tk) != 1) {
- pr_warn("incorrect number of testprobe hits\n");
+ if (WARN_ONCE(trace_kprobe_nhit(tk) != 1,
+ "incorrect number of testprobe hits."))
warn++;
- }
file = find_trace_probe_file(tk, top_trace_array());
- if (WARN_ON_ONCE(file == NULL)) {
- pr_warn("error on getting probe file.\n");
+ if (WARN_ONCE(file == NULL, "error on getting probe file.")) {
warn++;
} else
disable_trace_kprobe(
@@ -2098,18 +2139,15 @@ static __init int kprobe_trace_self_tests_init(void)
}
tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
- if (WARN_ON_ONCE(tk == NULL)) {
- pr_warn("error on getting 2nd test probe.\n");
+ if (WARN_ONCE(tk == NULL, "error on getting 2nd test probe.")) {
warn++;
} else {
- if (trace_kprobe_nhit(tk) != 1) {
- pr_warn("incorrect number of testprobe2 hits\n");
+ if (WARN_ONCE(trace_kprobe_nhit(tk) != 1,
+ "incorrect number of testprobe2 hits."))
warn++;
- }
file = find_trace_probe_file(tk, top_trace_array());
- if (WARN_ON_ONCE(file == NULL)) {
- pr_warn("error on getting probe file.\n");
+ if (WARN_ONCE(file == NULL, "error on getting probe file.")) {
warn++;
} else
disable_trace_kprobe(
@@ -2117,23 +2155,15 @@ static __init int kprobe_trace_self_tests_init(void)
}
ret = create_or_delete_trace_kprobe("-:testprobe");
- if (WARN_ON_ONCE(ret)) {
- pr_warn("error on deleting a probe.\n");
+ if (WARN_ONCE(ret, "error on deleting a probe."))
warn++;
- }
ret = create_or_delete_trace_kprobe("-:testprobe2");
- if (WARN_ON_ONCE(ret)) {
- pr_warn("error on deleting a probe.\n");
+ if (WARN_ONCE(ret, "error on deleting a probe."))
warn++;
- }
+
end:
- ret = dyn_events_release_all(&trace_kprobe_ops);
- if (WARN_ON_ONCE(ret)) {
- pr_warn("error on cleaning up probes.\n");
- warn++;
- }
/*
* Wait for the optimizer work to finish. Otherwise it might fiddle
* with probes in already freed __init text.
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-02 15:35:44 +0300