usermodehelper: check subprocess_info->path != NULL
[linux-2.6.git] / kernel / kprobes.c
index 95dd721..c62b854 100644 (file)
@@ -1077,6 +1077,7 @@ void __kprobes kprobe_flush_task(struct task_struct *tk)
                /* Early boot.  kretprobe_table_locks not yet initialized. */
                return;
 
+       INIT_HLIST_HEAD(&empty_rp);
        hash = hash_ptr(tk, KPROBE_HASH_BITS);
        head = &kretprobe_inst_table[hash];
        kretprobe_table_lock(hash, &flags);
@@ -1085,7 +1086,6 @@ void __kprobes kprobe_flush_task(struct task_struct *tk)
                        recycle_rp_inst(ri, &empty_rp);
        }
        kretprobe_table_unlock(hash, &flags);
-       INIT_HLIST_HEAD(&empty_rp);
        hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
                hlist_del(&ri->hlist);
                kfree(ri);
@@ -1334,8 +1334,10 @@ int __kprobes register_kprobe(struct kprobe *p)
        if (!kernel_text_address((unsigned long) p->addr) ||
            in_kprobes_functions((unsigned long) p->addr) ||
            ftrace_text_reserved(p->addr, p->addr) ||
-           jump_label_text_reserved(p->addr, p->addr))
-               goto fail_with_jump_label;
+           jump_label_text_reserved(p->addr, p->addr)) {
+               ret = -EINVAL;
+               goto cannot_probe;
+       }
 
        /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
        p->flags &= KPROBE_FLAG_DISABLED;
@@ -1352,7 +1354,7 @@ int __kprobes register_kprobe(struct kprobe *p)
                 * its code to prohibit unexpected unloading.
                 */
                if (unlikely(!try_module_get(probed_mod)))
-                       goto fail_with_jump_label;
+                       goto cannot_probe;
 
                /*
                 * If the module freed .init.text, we couldn't insert
@@ -1361,7 +1363,7 @@ int __kprobes register_kprobe(struct kprobe *p)
                if (within_module_init((unsigned long)p->addr, probed_mod) &&
                    probed_mod->state != MODULE_STATE_COMING) {
                        module_put(probed_mod);
-                       goto fail_with_jump_label;
+                       goto cannot_probe;
                }
                /* ret will be updated by following code */
        }
@@ -1409,7 +1411,7 @@ out:
 
        return ret;
 
-fail_with_jump_label:
+cannot_probe:
        preempt_enable();
        jump_label_unlock();
        return ret;
@@ -1673,8 +1675,12 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p,
                ri->rp = rp;
                ri->task = current;
 
-               if (rp->entry_handler && rp->entry_handler(ri, regs))
+               if (rp->entry_handler && rp->entry_handler(ri, regs)) {
+                       raw_spin_lock_irqsave(&rp->lock, flags);
+                       hlist_add_head(&ri->hlist, &rp->free_instances);
+                       raw_spin_unlock_irqrestore(&rp->lock, flags);
                        return 0;
+               }
 
                arch_prepare_kretprobe(ri, regs);