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-rw-r--r--kernel/kprobes.c55
1 files changed, 30 insertions, 25 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 993452324a1..22857003a65 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -133,7 +133,7 @@ kprobe_opcode_t __kprobes *get_insn_slot(void)
struct kprobe_insn_page *kip;
struct hlist_node *pos;
- retry:
+ retry:
hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) {
if (kip->nused < INSNS_PER_PAGE) {
int i;
@@ -155,9 +155,8 @@ kprobe_opcode_t __kprobes *get_insn_slot(void)
}
/* All out of space. Need to allocate a new page. Use slot 0. */
kip = kmalloc(sizeof(struct kprobe_insn_page), GFP_KERNEL);
- if (!kip) {
+ if (!kip)
return NULL;
- }
/*
* Use module_alloc so this page is within +/- 2GB of where the
@@ -246,9 +245,9 @@ void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty)
break;
}
}
- if (dirty && (++kprobe_garbage_slots > INSNS_PER_PAGE)) {
+
+ if (dirty && ++kprobe_garbage_slots > INSNS_PER_PAGE)
collect_garbage_slots();
- }
}
#endif
@@ -314,7 +313,6 @@ static void __kprobes aggr_post_handler(struct kprobe *p, struct pt_regs *regs,
reset_kprobe_instance();
}
}
- return;
}
static int __kprobes aggr_fault_handler(struct kprobe *p, struct pt_regs *regs,
@@ -533,8 +531,8 @@ static int __kprobes register_aggr_kprobe(struct kprobe *old_p,
static int __kprobes in_kprobes_functions(unsigned long addr)
{
- if (addr >= (unsigned long)__kprobes_text_start
- && addr < (unsigned long)__kprobes_text_end)
+ if (addr >= (unsigned long)__kprobes_text_start &&
+ addr < (unsigned long)__kprobes_text_end)
return -EINVAL;
return 0;
}
@@ -561,19 +559,24 @@ static int __kprobes __register_kprobe(struct kprobe *p,
return -EINVAL;
p->addr = (kprobe_opcode_t *)(((char *)p->addr)+ p->offset);
- if ((!kernel_text_address((unsigned long) p->addr)) ||
- in_kprobes_functions((unsigned long) p->addr))
+ if (!kernel_text_address((unsigned long) p->addr) ||
+ in_kprobes_functions((unsigned long) p->addr))
return -EINVAL;
p->mod_refcounted = 0;
- /* Check are we probing a module */
- if ((probed_mod = module_text_address((unsigned long) p->addr))) {
+
+ /*
+ * Check if are we probing a module.
+ */
+ probed_mod = module_text_address((unsigned long) p->addr);
+ if (probed_mod) {
struct module *calling_mod = module_text_address(called_from);
- /* We must allow modules to probe themself and
- * in this case avoid incrementing the module refcount,
- * so as to allow unloading of self probing modules.
+ /*
+ * We must allow modules to probe themself and in this case
+ * avoid incrementing the module refcount, so as to allow
+ * unloading of self probing modules.
*/
- if (calling_mod && (calling_mod != probed_mod)) {
+ if (calling_mod && calling_mod != probed_mod) {
if (unlikely(!try_module_get(probed_mod)))
return -EINVAL;
p->mod_refcounted = 1;
@@ -591,7 +594,8 @@ static int __kprobes __register_kprobe(struct kprobe *p,
goto out;
}
- if ((ret = arch_prepare_kprobe(p)) != 0)
+ ret = arch_prepare_kprobe(p);
+ if (ret)
goto out;
INIT_HLIST_NODE(&p->hlist);
@@ -614,8 +618,7 @@ out:
int __kprobes register_kprobe(struct kprobe *p)
{
- return __register_kprobe(p,
- (unsigned long)__builtin_return_address(0));
+ return __register_kprobe(p, (unsigned long)__builtin_return_address(0));
}
void __kprobes unregister_kprobe(struct kprobe *p)
@@ -639,9 +642,9 @@ void __kprobes unregister_kprobe(struct kprobe *p)
return;
}
valid_p:
- if ((old_p == p) || ((old_p->pre_handler == aggr_pre_handler) &&
- (p->list.next == &old_p->list) &&
- (p->list.prev == &old_p->list))) {
+ if (old_p == p ||
+ (old_p->pre_handler == aggr_pre_handler &&
+ p->list.next == &old_p->list && p->list.prev == &old_p->list)) {
/* Only probe on the hash list */
arch_disarm_kprobe(p);
hlist_del_rcu(&old_p->hlist);
@@ -654,9 +657,11 @@ valid_p:
mutex_unlock(&kprobe_mutex);
synchronize_sched();
- if (p->mod_refcounted &&
- (mod = module_text_address((unsigned long)p->addr)))
- module_put(mod);
+ if (p->mod_refcounted) {
+ mod = module_text_address((unsigned long)p->addr);
+ if (mod)
+ module_put(mod);
+ }
if (cleanup_p) {
if (p != old_p) {