1 files changed, 13 insertions, 6 deletions

diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index 0ce9fb245034..59a9c35c4598 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -26,11 +26,12 @@
 #include <linux/stop_machine.h>
 #include <linux/kdebug.h>
 #include <linux/uaccess.h>
-#include <asm/cacheflush.h>
-#include <asm/sections.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/hardirq.h>
+#include <asm/cacheflush.h>
+#include <asm/sections.h>
+#include <asm/dis.h>
 
 DEFINE_PER_CPU(struct kprobe *, current_kprobe);
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -59,6 +60,8 @@ struct kprobe_insn_cache kprobe_dmainsn_slots = {
 
 static int __kprobes is_prohibited_opcode(kprobe_opcode_t *insn)
 {
+        if (!is_known_insn((unsigned char *)insn))
+                return -EINVAL;
         switch (insn[0] >> 8) {
         case 0x0c:      /* bassm */
         case 0x0b:      /* bsm   */
@@ -67,6 +70,11 @@ static int __kprobes is_prohibited_opcode(kprobe_opcode_t *insn)
         case 0xac:      /* stnsm */
         case 0xad:      /* stosm */
                 return -EINVAL;
+        case 0xc6:
+                switch (insn[0] & 0x0f) {
+                case 0x00: /* exrl   */
+                        return -EINVAL;
+                }
         }
         switch (insn[0]) {
         case 0x0101:    /* pr    */
@@ -180,7 +188,6 @@ static int __kprobes is_insn_relative_long(kprobe_opcode_t *insn)
                 break;
         case 0xc6:
                 switch (insn[0] & 0x0f) {
-                case 0x00: /* exrl   */
                 case 0x02: /* pfdrl  */
                 case 0x04: /* cghrl  */
                 case 0x05: /* chrl   */
@@ -204,7 +211,7 @@ static void __kprobes copy_instruction(struct kprobe *p)
         s64 disp, new_disp;
         u64 addr, new_addr;
 
-        memcpy(p->ainsn.insn, p->addr, ((p->opcode >> 14) + 3) & -2);
+        memcpy(p->ainsn.insn, p->addr, insn_length(p->opcode >> 8));
         if (!is_insn_relative_long(p->ainsn.insn))
                 return;
         /*
@@ -248,7 +255,7 @@ static int __kprobes s390_get_insn_slot(struct kprobe *p)
         p->ainsn.insn = NULL;
         if (is_kernel_addr(p->addr))
                 p->ainsn.insn = get_dmainsn_slot();
-        if (is_module_addr(p->addr))
+        else if (is_module_addr(p->addr))
                 p->ainsn.insn = get_insn_slot();
         return p->ainsn.insn ? 0 : -ENOMEM;
 }
@@ -604,7 +611,7 @@ static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs)
                 ip += (unsigned long) p->addr - (unsigned long) p->ainsn.insn;
 
         if (fixup & FIXUP_BRANCH_NOT_TAKEN) {
-                int ilen = ((p->ainsn.insn[0] >> 14) + 3) & -2;
+                int ilen = insn_length(p->ainsn.insn[0] >> 8);
                 if (ip - (unsigned long) p->ainsn.insn == ilen)
                         ip = (unsigned long) p->addr + ilen;
         }