Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6

[linux-2.6-omap-h63xx.git] / arch / i386 / kernel / kprobes.c

diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index afe6505ca0b3a78af53db084d60574540ea7361d..d98e44b16fe20fa1edbda6d0246bc95b3a49cede 100644 (file)
--- 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;
 }