1 files changed, 30 insertions, 30 deletions

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 5016bfb682b9..a55bfadfd766 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -518,20 +518,20 @@ static inline void copy_kprobe(struct kprobe *old_p, struct kprobe *p)
 }
 
 /*
-* Add the new probe to old_p->list. Fail if this is the
+* Add the new probe to ap->list. Fail if this is the
 * second jprobe at the address - two jprobes can't coexist
 */
-static int __kprobes add_new_kprobe(struct kprobe *old_p, struct kprobe *p)
+static int __kprobes add_new_kprobe(struct kprobe *ap, struct kprobe *p)
 {
         if (p->break_handler) {
-                if (old_p->break_handler)
+                if (ap->break_handler)
                         return -EEXIST;
-                list_add_tail_rcu(&p->list, &old_p->list);
-                old_p->break_handler = aggr_break_handler;
+                list_add_tail_rcu(&p->list, &ap->list);
+                ap->break_handler = aggr_break_handler;
         } else
-                list_add_rcu(&p->list, &old_p->list);
-        if (p->post_handler && !old_p->post_handler)
-                old_p->post_handler = aggr_post_handler;
+                list_add_rcu(&p->list, &ap->list);
+        if (p->post_handler && !ap->post_handler)
+                ap->post_handler = aggr_post_handler;
         return 0;
 }
 
@@ -544,6 +544,7 @@ static inline void add_aggr_kprobe(struct kprobe *ap, struct kprobe *p)
         copy_kprobe(p, ap);
         flush_insn_slot(ap);
         ap->addr = p->addr;
+        ap->flags = p->flags;
         ap->pre_handler = aggr_pre_handler;
         ap->fault_handler = aggr_fault_handler;
         /* We don't care the kprobe which has gone. */
@@ -566,44 +567,43 @@ static int __kprobes register_aggr_kprobe(struct kprobe *old_p,
                                           struct kprobe *p)
 {
         int ret = 0;
-        struct kprobe *ap;
+        struct kprobe *ap = old_p;
 
-        if (kprobe_gone(old_p)) {
+        if (old_p->pre_handler != aggr_pre_handler) {
+                /* If old_p is not an aggr_probe, create new aggr_kprobe. */
+                ap = kzalloc(sizeof(struct kprobe), GFP_KERNEL);
+                if (!ap)
+                        return -ENOMEM;
+                add_aggr_kprobe(ap, old_p);
+        }
+
+        if (kprobe_gone(ap)) {
                 /*
                  * Attempting to insert new probe at the same location that
                  * had a probe in the module vaddr area which already
                  * freed. So, the instruction slot has already been
                  * released. We need a new slot for the new probe.
                  */
-                ret = arch_prepare_kprobe(old_p);
+                ret = arch_prepare_kprobe(ap);
                 if (ret)
+                        /*
+                         * Even if fail to allocate new slot, don't need to
+                         * free aggr_probe. It will be used next time, or
+                         * freed by unregister_kprobe.
+                         */
                         return ret;
-        }
-        if (old_p->pre_handler == aggr_pre_handler) {
-                copy_kprobe(old_p, p);
-                ret = add_new_kprobe(old_p, p);
-                ap = old_p;
-        } else {
-                ap = kzalloc(sizeof(struct kprobe), GFP_KERNEL);
-                if (!ap) {
-                        if (kprobe_gone(old_p))
-                                arch_remove_kprobe(old_p);
-                        return -ENOMEM;
-                }
-                add_aggr_kprobe(ap, old_p);
-                copy_kprobe(ap, p);
-                ret = add_new_kprobe(ap, p);
-        }
-        if (kprobe_gone(old_p)) {
+                /* Clear gone flag to prevent allocating new slot again. */
+                ap->flags &= ~KPROBE_FLAG_GONE;
                 /*
                  * If the old_p has gone, its breakpoint has been disarmed.
                  * We have to arm it again after preparing real kprobes.
                  */
-                ap->flags &= ~KPROBE_FLAG_GONE;
                 if (kprobe_enabled)
                         arch_arm_kprobe(ap);
         }
-        return ret;
+
+        copy_kprobe(ap, p);
+        return add_new_kprobe(ap, p);
 }
 
 static int __kprobes in_kprobes_functions(unsigned long addr)