kprobes: support kretprobe blacklist

[pandora-kernel.git] / arch / s390 / kernel / kprobes.c

diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index 23c61f6..c5549a2 100644 (file)
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -24,8 +24,8 @@
 #include <linux/ptrace.h>
 #include <linux/preempt.h>
 #include <linux/stop_machine.h>
+#include <linux/kdebug.h>
 #include <asm/cacheflush.h>
-#include <asm/kdebug.h>
 #include <asm/sections.h>
 #include <asm/uaccess.h>
 #include <linux/module.h>
@@ -33,6 +33,8 @@
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
+struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}};
+
 int __kprobes arch_prepare_kprobe(struct kprobe *p)
 {
        /* Make sure the probe isn't going on a difficult instruction */
@@ -85,7 +87,7 @@ void __kprobes get_instruction_type(struct arch_specific_insn *ainsn)
        ainsn->reg = (*ainsn->insn & 0xf0) >> 4;
 
        /* save the instruction length (pop 5-5) in bytes */
-       switch (*(__u8 *) (ainsn->insn) >> 4) {
+       switch (*(__u8 *) (ainsn->insn) >> 6) {
        case 0:
                ainsn->ilen = 2;
                break;
@@ -271,23 +273,13 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
 }
 
 /* Called with kretprobe_lock held */
-void __kprobes arch_prepare_kretprobe(struct kretprobe *rp,
+void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
                                        struct pt_regs *regs)
 {
-       struct kretprobe_instance *ri;
-
-       if ((ri = get_free_rp_inst(rp)) != NULL) {
-               ri->rp = rp;
-               ri->task = current;
-               ri->ret_addr = (kprobe_opcode_t *) regs->gprs[14];
-
-               /* Replace the return addr with trampoline addr */
-               regs->gprs[14] = (unsigned long)&kretprobe_trampoline;
+       ri->ret_addr = (kprobe_opcode_t *) regs->gprs[14];
 
-               add_rp_inst(ri);
-       } else {
-               rp->nmissed++;
-       }
+       /* Replace the return addr with trampoline addr */
+       regs->gprs[14] = (unsigned long)&kretprobe_trampoline;
 }
 
 static int __kprobes kprobe_handler(struct pt_regs *regs)
@@ -423,7 +415,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
                        break;
                }
        }
-       BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
+       kretprobe_assert(ri, orig_ret_address, trampoline_address);
        regs->psw.addr = orig_ret_address | PSW_ADDR_AMODE;
 
        reset_current_kprobe();
@@ -671,3 +663,10 @@ int __init arch_init_kprobes(void)
 {
        return register_kprobe(&trampoline_p);
 }
+
+int __kprobes arch_trampoline_kprobe(struct kprobe *p)
+{
+       if (p->addr == (kprobe_opcode_t *) & kretprobe_trampoline)
+               return 1;
+       return 0;
+}