From 057e8bff7763c4f622b27a3e0b701519dcffc466 Mon Sep 17 00:00:00 2001
From: Vyacheslav Cherkashin <v.cherkashin@samsung.com>
Date: Tue, 9 Apr 2013 14:10:45 +0400
Subject: [PATCH] [IMPROVE] add entry_handler() in kretprobe

---
 kprobe/arch/asm-arm/dbi_kprobes.c | 5 +++++
 kprobe/dbi_kprobes.c              | 5 +++--
 kprobe/dbi_kprobes.h              | 3 +++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/kprobe/arch/asm-arm/dbi_kprobes.c b/kprobe/arch/asm-arm/dbi_kprobes.c
index 197bc1c..3acaf77 100644
--- a/kprobe/arch/asm-arm/dbi_kprobes.c
+++ b/kprobe/arch/asm-arm/dbi_kprobes.c
@@ -488,6 +488,11 @@ void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs)
 	if ((ri = get_free_rp_inst(rp)) != NULL) {
 		ri->rp = rp;
 		ri->task = current;
+
+		if (rp->entry_handler) {
+			rp->entry_handler(ri, regs, ri->rp->priv_arg);
+		}
+
 		ri->ret_addr = (kprobe_opcode_t *)regs->uregs[14];
 		ri->sp = (kprobe_opcode_t *)regs->ARM_sp; //uregs[13];
 
diff --git a/kprobe/dbi_kprobes.c b/kprobe/dbi_kprobes.c
index 0fba5d5..fab4f28 100644
--- a/kprobe/dbi_kprobes.c
+++ b/kprobe/dbi_kprobes.c
@@ -613,6 +613,7 @@ int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
 	spin_lock_irqsave(&kretprobe_lock, flags);
 	if (!rp->disarm)
 		arch_prepare_kretprobe(rp, regs);
+
 	spin_unlock_irqrestore(&kretprobe_lock, flags);
 	DBPRINTF ("END\n");
 	return 0;
@@ -645,7 +646,7 @@ int alloc_nodes_kretprobe(struct kretprobe *rp)
 	}
 
 	for (i = 0; i < alloc_nodes; i++) {
-		inst = kmalloc(sizeof(struct kretprobe_instance), GFP_ATOMIC);
+		inst = kmalloc(sizeof(inst) + rp->data_size, GFP_ATOMIC);
 		if (inst == NULL) {
 			free_rp_inst(rp);
 			return -ENOMEM;
@@ -689,7 +690,7 @@ int dbi_register_kretprobe(struct kretprobe *rp)
 	INIT_HLIST_HEAD(&rp->used_instances);
 	INIT_HLIST_HEAD(&rp->free_instances);
 	for (i = 0; i < rp->maxactive; i++) {
-		inst = kmalloc(sizeof(struct kretprobe_instance), GFP_KERNEL);
+		inst = kmalloc(sizeof(*inst) + rp->data_size, GFP_KERNEL);
 		if (inst == NULL) {
 			free_rp_inst(rp);
 			return -ENOMEM;
diff --git a/kprobe/dbi_kprobes.h b/kprobe/dbi_kprobes.h
index 44355e8..d193ede 100644
--- a/kprobe/dbi_kprobes.h
+++ b/kprobe/dbi_kprobes.h
@@ -186,10 +186,12 @@ struct kretprobe
 {
 	struct kprobe kp;
 	kretprobe_handler_t handler;
+	kretprobe_handler_t entry_handler;
 	void *priv_arg;
 	int maxactive;
 	int nmissed;
 	int disarm;
+	size_t data_size;
 	struct hlist_head free_instances;
 	struct hlist_head used_instances;
 };
@@ -203,6 +205,7 @@ struct kretprobe_instance
 	kprobe_opcode_t *ret_addr;
 	kprobe_opcode_t *sp;
 	struct task_struct *task;
+	char data[0];
 };
 
 
-- 
2.7.4