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Diffstat (limited to 'arch/i386/kernel/kprobes.c')
-rw-r--r--arch/i386/kernel/kprobes.c41
1 files changed, 23 insertions, 18 deletions
diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index afe6505ca0b..d98e44b16fe 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -230,20 +230,20 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe *rp,
struct pt_regs *regs)
{
unsigned long *sara = (unsigned long *)&regs->esp;
- struct kretprobe_instance *ri;
- if ((ri = get_free_rp_inst(rp)) != NULL) {
- ri->rp = rp;
- ri->task = current;
+ struct kretprobe_instance *ri;
+
+ if ((ri = get_free_rp_inst(rp)) != NULL) {
+ ri->rp = rp;
+ ri->task = current;
ri->ret_addr = (kprobe_opcode_t *) *sara;
/* Replace the return addr with trampoline addr */
*sara = (unsigned long) &kretprobe_trampoline;
-
- add_rp_inst(ri);
- } else {
- rp->nmissed++;
- }
+ add_rp_inst(ri);
+ } else {
+ rp->nmissed++;
+ }
}
/*
@@ -359,7 +359,7 @@ no_kprobe:
void __kprobes kretprobe_trampoline_holder(void)
{
asm volatile ( ".global kretprobe_trampoline\n"
- "kretprobe_trampoline: \n"
+ "kretprobe_trampoline: \n"
" pushf\n"
/* skip cs, eip, orig_eax, es, ds */
" subl $20, %esp\n"
@@ -395,14 +395,15 @@ no_kprobe:
*/
fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
{
- struct kretprobe_instance *ri = NULL;
- struct hlist_head *head;
- struct hlist_node *node, *tmp;
+ struct kretprobe_instance *ri = NULL;
+ struct hlist_head *head, empty_rp;
+ struct hlist_node *node, *tmp;
unsigned long flags, orig_ret_address = 0;
unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline;
+ INIT_HLIST_HEAD(&empty_rp);
spin_lock_irqsave(&kretprobe_lock, flags);
- head = kretprobe_inst_table_head(current);
+ head = kretprobe_inst_table_head(current);
/*
* It is possible to have multiple instances associated with a given
@@ -413,14 +414,14 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
* We can handle this because:
* - instances are always inserted at the head of the list
* - when multiple return probes are registered for the same
- * function, the first instance's ret_addr will point to the
+ * function, the first instance's ret_addr will point to the
* real return address, and all the rest will point to
* kretprobe_trampoline
*/
hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
- if (ri->task != current)
+ if (ri->task != current)
/* another task is sharing our hash bucket */
- continue;
+ continue;
if (ri->rp && ri->rp->handler){
__get_cpu_var(current_kprobe) = &ri->rp->kp;
@@ -429,7 +430,7 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
}
orig_ret_address = (unsigned long)ri->ret_addr;
- recycle_rp_inst(ri);
+ recycle_rp_inst(ri, &empty_rp);
if (orig_ret_address != trampoline_address)
/*
@@ -444,6 +445,10 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
spin_unlock_irqrestore(&kretprobe_lock, flags);
+ hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
+ hlist_del(&ri->hlist);
+ kfree(ri);
+ }
return (void*)orig_ret_address;
}