*/
static void do_optimize_kprobes(void)
{
+ lockdep_assert_held(&text_mutex);
/*
* The optimization/unoptimization refers online_cpus via
* stop_machine() and cpu-hotplug modifies online_cpus.
list_empty(&optimizing_list))
return;
- mutex_lock(&text_mutex);
arch_optimize_kprobes(&optimizing_list);
- mutex_unlock(&text_mutex);
}
/*
{
struct optimized_kprobe *op, *tmp;
+ lockdep_assert_held(&text_mutex);
/* See comment in do_optimize_kprobes() */
lockdep_assert_cpus_held();
if (list_empty(&unoptimizing_list))
return;
- mutex_lock(&text_mutex);
arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
/* Loop free_list for disarming */
list_for_each_entry_safe(op, tmp, &freeing_list, list) {
} else
list_del_init(&op->list);
}
- mutex_unlock(&text_mutex);
}
/* Reclaim all kprobes on the free_list */
struct optimized_kprobe *op, *tmp;
list_for_each_entry_safe(op, tmp, &freeing_list, list) {
- BUG_ON(!kprobe_unused(&op->kp));
list_del_init(&op->list);
+ if (WARN_ON_ONCE(!kprobe_unused(&op->kp))) {
+ /*
+ * This must not happen, but if there is a kprobe
+ * still in use, keep it on kprobes hash list.
+ */
+ continue;
+ }
free_aggr_kprobe(&op->kp);
}
}
{
mutex_lock(&kprobe_mutex);
cpus_read_lock();
+ mutex_lock(&text_mutex);
/* Lock modules while optimizing kprobes */
mutex_lock(&module_mutex);
do_free_cleaned_kprobes();
mutex_unlock(&module_mutex);
+ mutex_unlock(&text_mutex);
cpus_read_unlock();
mutex_unlock(&kprobe_mutex);
}
/* Cancel unoptimizing for reusing */
-static void reuse_unused_kprobe(struct kprobe *ap)
+static int reuse_unused_kprobe(struct kprobe *ap)
{
struct optimized_kprobe *op;
* there is still a relative jump) and disabled.
*/
op = container_of(ap, struct optimized_kprobe, kp);
- if (unlikely(list_empty(&op->list)))
- printk(KERN_WARNING "Warning: found a stray unused "
- "aggrprobe@%p\n", ap->addr);
+ WARN_ON_ONCE(list_empty(&op->list));
/* Enable the probe again */
ap->flags &= ~KPROBE_FLAG_DISABLED;
/* Optimize it again (remove from op->list) */
- BUG_ON(!kprobe_optready(ap));
+ if (!kprobe_optready(ap))
+ return -EINVAL;
+
optimize_kprobe(ap);
+ return 0;
}
/* Remove optimized instructions */
#define kprobe_disarmed(p) kprobe_disabled(p)
#define wait_for_kprobe_optimizer() do {} while (0)
-/* There should be no unused kprobes can be reused without optimization */
-static void reuse_unused_kprobe(struct kprobe *ap)
+static int reuse_unused_kprobe(struct kprobe *ap)
{
+ /*
+ * If the optimized kprobe is NOT supported, the aggr kprobe is
+ * released at the same time that the last aggregated kprobe is
+ * unregistered.
+ * Thus there should be no chance to reuse unused kprobe.
+ */
printk(KERN_ERR "Error: There should be no unused kprobe here.\n");
- BUG_ON(kprobe_unused(ap));
+ return -EINVAL;
}
static void free_aggr_kprobe(struct kprobe *p)
ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
(unsigned long)p->addr, 0, 0);
- WARN(ret < 0, "Failed to arm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+ WARN(ret < 0, "Failed to arm kprobe-ftrace at %pS (%d)\n", p->addr, ret);
kprobe_ftrace_enabled++;
if (kprobe_ftrace_enabled == 1) {
ret = register_ftrace_function(&kprobe_ftrace_ops);
}
ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
(unsigned long)p->addr, 1, 0);
- WARN(ret < 0, "Failed to disarm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+ WARN(ret < 0, "Failed to disarm kprobe-ftrace at %pS (%d)\n", p->addr, ret);
}
#else /* !CONFIG_KPROBES_ON_FTRACE */
#define prepare_kprobe(p) arch_prepare_kprobe(p)
goto out;
}
init_aggr_kprobe(ap, orig_p);
- } else if (kprobe_unused(ap))
+ } else if (kprobe_unused(ap)) {
/* This probe is going to die. Rescue it */
- reuse_unused_kprobe(ap);
+ ret = reuse_unused_kprobe(ap);
+ if (ret)
+ goto out;
+ }
if (kprobe_gone(ap)) {
/*
/* Ensure it is not in reserved area nor out of text */
if (!kernel_text_address((unsigned long) p->addr) ||
within_kprobe_blacklist((unsigned long) p->addr) ||
- jump_label_text_reserved(p->addr, p->addr)) {
+ jump_label_text_reserved(p->addr, p->addr) ||
+ find_bug((unsigned long)p->addr)) {
ret = -EINVAL;
goto out;
}
}
EXPORT_SYMBOL_GPL(enable_kprobe);
+/* Caller must NOT call this in usual path. This is only for critical case */
void dump_kprobe(struct kprobe *kp)
{
- printk(KERN_WARNING "Dumping kprobe:\n");
- printk(KERN_WARNING "Name: %s\nAddress: %p\nOffset: %x\n",
- kp->symbol_name, kp->addr, kp->offset);
+ pr_err("Dumping kprobe:\n");
+ pr_err("Name: %s\nOffset: %x\nAddress: %pS\n",
+ kp->symbol_name, kp->offset, kp->addr);
}
NOKPROBE_SYMBOL(dump_kprobe);
+int kprobe_add_ksym_blacklist(unsigned long entry)
+{
+ struct kprobe_blacklist_entry *ent;
+ unsigned long offset = 0, size = 0;
+
+ if (!kernel_text_address(entry) ||
+ !kallsyms_lookup_size_offset(entry, &size, &offset))
+ return -EINVAL;
+
+ ent = kmalloc(sizeof(*ent), GFP_KERNEL);
+ if (!ent)
+ return -ENOMEM;
+ ent->start_addr = entry;
+ ent->end_addr = entry + size;
+ INIT_LIST_HEAD(&ent->list);
+ list_add_tail(&ent->list, &kprobe_blacklist);
+
+ return (int)size;
+}
+
+/* Add all symbols in given area into kprobe blacklist */
+int kprobe_add_area_blacklist(unsigned long start, unsigned long end)
+{
+ unsigned long entry;
+ int ret = 0;
+
+ for (entry = start; entry < end; entry += ret) {
+ ret = kprobe_add_ksym_blacklist(entry);
+ if (ret < 0)
+ return ret;
+ if (ret == 0) /* In case of alias symbol */
+ ret = 1;
+ }
+ return 0;
+}
+
+int __init __weak arch_populate_kprobe_blacklist(void)
+{
+ return 0;
+}
+
/*
* Lookup and populate the kprobe_blacklist.
*
static int __init populate_kprobe_blacklist(unsigned long *start,
unsigned long *end)
{
+ unsigned long entry;
unsigned long *iter;
- struct kprobe_blacklist_entry *ent;
- unsigned long entry, offset = 0, size = 0;
+ int ret;
for (iter = start; iter < end; iter++) {
entry = arch_deref_entry_point((void *)*iter);
-
- if (!kernel_text_address(entry) ||
- !kallsyms_lookup_size_offset(entry, &size, &offset)) {
- pr_err("Failed to find blacklist at %p\n",
- (void *)entry);
+ ret = kprobe_add_ksym_blacklist(entry);
+ if (ret == -EINVAL)
continue;
- }
-
- ent = kmalloc(sizeof(*ent), GFP_KERNEL);
- if (!ent)
- return -ENOMEM;
- ent->start_addr = entry;
- ent->end_addr = entry + size;
- INIT_LIST_HEAD(&ent->list);
- list_add_tail(&ent->list, &kprobe_blacklist);
+ if (ret < 0)
+ return ret;
}
- return 0;
+
+ /* Symbols in __kprobes_text are blacklisted */
+ ret = kprobe_add_area_blacklist((unsigned long)__kprobes_text_start,
+ (unsigned long)__kprobes_text_end);
+
+ return ret ? : arch_populate_kprobe_blacklist();
}
/* Module notifier call back, checking kprobes on the module */
struct kprobe_blacklist_entry *ent =
list_entry(v, struct kprobe_blacklist_entry, list);
- seq_printf(m, "0x%p-0x%p\t%ps\n", (void *)ent->start_addr,
- (void *)ent->end_addr, (void *)ent->start_addr);
+ /*
+ * If /proc/kallsyms is not showing kernel address, we won't
+ * show them here either.
+ */
+ if (!kallsyms_show_value())
+ seq_printf(m, "0x%px-0x%px\t%ps\n", NULL, NULL,
+ (void *)ent->start_addr);
+ else
+ seq_printf(m, "0x%px-0x%px\t%ps\n", (void *)ent->start_addr,
+ (void *)ent->end_addr, (void *)ent->start_addr);
return 0;
}
if (!dir)
return -ENOMEM;
- file = debugfs_create_file("list", 0444, dir, NULL,
+ file = debugfs_create_file("list", 0400, dir, NULL,
&debugfs_kprobes_operations);
if (!file)
goto error;
if (!file)
goto error;
- file = debugfs_create_file("blacklist", 0444, dir, NULL,
+ file = debugfs_create_file("blacklist", 0400, dir, NULL,
&debugfs_kprobe_blacklist_ops);
if (!file)
goto error;