Merge tag 'noinstr-lds-2020-05-19' into core/kprobes
Get the noinstr section and markers to base the kprobe changes on.
diff --git a/include/linux/module.h b/include/linux/module.h
index 1ad393e..1192097 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -489,6 +489,12 @@
unsigned int num_ftrace_callsites;
unsigned long *ftrace_callsites;
#endif
+#ifdef CONFIG_KPROBES
+ void *kprobes_text_start;
+ unsigned int kprobes_text_size;
+ unsigned long *kprobe_blacklist;
+ unsigned int num_kprobe_blacklist;
+#endif
#ifdef CONFIG_LIVEPATCH
bool klp; /* Is this a livepatch module? */
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 2625c24..9eb5acf 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2179,6 +2179,24 @@
return 0;
}
+/* Remove all symbols in given area from kprobe blacklist */
+static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end)
+{
+ struct kprobe_blacklist_entry *ent, *n;
+
+ list_for_each_entry_safe(ent, n, &kprobe_blacklist, list) {
+ if (ent->start_addr < start || ent->start_addr >= end)
+ continue;
+ list_del(&ent->list);
+ kfree(ent);
+ }
+}
+
+static void kprobe_remove_ksym_blacklist(unsigned long entry)
+{
+ kprobe_remove_area_blacklist(entry, entry + 1);
+}
+
int __init __weak arch_populate_kprobe_blacklist(void)
{
return 0;
@@ -2215,6 +2233,40 @@
return ret ? : arch_populate_kprobe_blacklist();
}
+static void add_module_kprobe_blacklist(struct module *mod)
+{
+ unsigned long start, end;
+ int i;
+
+ if (mod->kprobe_blacklist) {
+ for (i = 0; i < mod->num_kprobe_blacklist; i++)
+ kprobe_add_ksym_blacklist(mod->kprobe_blacklist[i]);
+ }
+
+ start = (unsigned long)mod->kprobes_text_start;
+ if (start) {
+ end = start + mod->kprobes_text_size;
+ kprobe_add_area_blacklist(start, end);
+ }
+}
+
+static void remove_module_kprobe_blacklist(struct module *mod)
+{
+ unsigned long start, end;
+ int i;
+
+ if (mod->kprobe_blacklist) {
+ for (i = 0; i < mod->num_kprobe_blacklist; i++)
+ kprobe_remove_ksym_blacklist(mod->kprobe_blacklist[i]);
+ }
+
+ start = (unsigned long)mod->kprobes_text_start;
+ if (start) {
+ end = start + mod->kprobes_text_size;
+ kprobe_remove_area_blacklist(start, end);
+ }
+}
+
/* Module notifier call back, checking kprobes on the module */
static int kprobes_module_callback(struct notifier_block *nb,
unsigned long val, void *data)
@@ -2225,6 +2277,11 @@
unsigned int i;
int checkcore = (val == MODULE_STATE_GOING);
+ if (val == MODULE_STATE_COMING) {
+ mutex_lock(&kprobe_mutex);
+ add_module_kprobe_blacklist(mod);
+ mutex_unlock(&kprobe_mutex);
+ }
if (val != MODULE_STATE_GOING && val != MODULE_STATE_LIVE)
return NOTIFY_DONE;
@@ -2255,6 +2312,8 @@
kill_kprobe(p);
}
}
+ if (val == MODULE_STATE_GOING)
+ remove_module_kprobe_blacklist(mod);
mutex_unlock(&kprobe_mutex);
return NOTIFY_DONE;
}
@@ -2420,6 +2479,7 @@
/* kprobes/blacklist -- shows which functions can not be probed */
static void *kprobe_blacklist_seq_start(struct seq_file *m, loff_t *pos)
{
+ mutex_lock(&kprobe_mutex);
return seq_list_start(&kprobe_blacklist, *pos);
}
@@ -2446,10 +2506,15 @@
return 0;
}
+static void kprobe_blacklist_seq_stop(struct seq_file *f, void *v)
+{
+ mutex_unlock(&kprobe_mutex);
+}
+
static const struct seq_operations kprobe_blacklist_seq_ops = {
.start = kprobe_blacklist_seq_start,
.next = kprobe_blacklist_seq_next,
- .stop = kprobe_seq_stop, /* Reuse void function */
+ .stop = kprobe_blacklist_seq_stop,
.show = kprobe_blacklist_seq_show,
};
diff --git a/kernel/module.c b/kernel/module.c
index 646f1e2..faf7337 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -3194,6 +3194,13 @@
sizeof(*mod->ei_funcs),
&mod->num_ei_funcs);
#endif
+#ifdef CONFIG_KPROBES
+ mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1,
+ &mod->kprobes_text_size);
+ mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist",
+ sizeof(unsigned long),
+ &mod->num_kprobe_blacklist);
+#endif
mod->extable = section_objs(info, "__ex_table",
sizeof(*mod->extable), &mod->num_exentries);
diff --git a/samples/kprobes/kprobe_example.c b/samples/kprobes/kprobe_example.c
index d693c23..501911d 100644
--- a/samples/kprobes/kprobe_example.c
+++ b/samples/kprobes/kprobe_example.c
@@ -25,7 +25,7 @@
};
/* kprobe pre_handler: called just before the probed instruction is executed */
-static int handler_pre(struct kprobe *p, struct pt_regs *regs)
+static int __kprobes handler_pre(struct kprobe *p, struct pt_regs *regs)
{
#ifdef CONFIG_X86
pr_info("<%s> pre_handler: p->addr = 0x%p, ip = %lx, flags = 0x%lx\n",
@@ -54,7 +54,7 @@
}
/* kprobe post_handler: called after the probed instruction is executed */
-static void handler_post(struct kprobe *p, struct pt_regs *regs,
+static void __kprobes handler_post(struct kprobe *p, struct pt_regs *regs,
unsigned long flags)
{
#ifdef CONFIG_X86
@@ -90,6 +90,8 @@
/* Return 0 because we don't handle the fault. */
return 0;
}
+/* NOKPROBE_SYMBOL() is also available */
+NOKPROBE_SYMBOL(handler_fault);
static int __init kprobe_init(void)
{
diff --git a/samples/kprobes/kretprobe_example.c b/samples/kprobes/kretprobe_example.c
index 186315c..013e8e6 100644
--- a/samples/kprobes/kretprobe_example.c
+++ b/samples/kprobes/kretprobe_example.c
@@ -48,6 +48,7 @@
data->entry_stamp = ktime_get();
return 0;
}
+NOKPROBE_SYMBOL(entry_handler);
/*
* Return-probe handler: Log the return value and duration. Duration may turn
@@ -67,6 +68,7 @@
func_name, retval, (long long)delta);
return 0;
}
+NOKPROBE_SYMBOL(ret_handler);
static struct kretprobe my_kretprobe = {
.handler = ret_handler,
