1 files changed, 27 insertions, 14 deletions

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 229951ffc351..8726779e1409 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -32,6 +32,7 @@
 #include <linux/perf_event.h>
 #include <linux/magic.h>
 #include <linux/ratelimit.h>
+#include <linux/context_tracking.h>
 
 #include <asm/firmware.h>
 #include <asm/page.h>
@@ -196,6 +197,7 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault)
 int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
                             unsigned long error_code)
 {
+        enum ctx_state prev_state = exception_enter();
         struct vm_area_struct * vma;
         struct mm_struct *mm = current->mm;
         unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
@@ -204,6 +206,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
         int trap = TRAP(regs);
         int is_exec = trap == 0x400;
         int fault;
+        int rc = 0;
 
 #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
         /*
@@ -230,28 +233,30 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
          * look at it
          */
         if (error_code & ICSWX_DSI_UCT) {
-                int rc = acop_handle_fault(regs, address, error_code);
+                rc = acop_handle_fault(regs, address, error_code);
                 if (rc)
-                        return rc;
+                        goto bail;
         }
 #endif /* CONFIG_PPC_ICSWX */
 
         if (notify_page_fault(regs))
-                return 0;
+                goto bail;
 
         if (unlikely(debugger_fault_handler(regs)))
-                return 0;
+                goto bail;
 
         /* On a kernel SLB miss we can only check for a valid exception entry */
-        if (!user_mode(regs) && (address >= TASK_SIZE))
-                return SIGSEGV;
+        if (!user_mode(regs) && (address >= TASK_SIZE)) {
+                rc = SIGSEGV;
+                goto bail;
+        }
 
 #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE) || \
                              defined(CONFIG_PPC_BOOK3S_64))
         if (error_code & DSISR_DABRMATCH) {
                 /* breakpoint match */
                 do_break(regs, address, error_code);
-                return 0;
+                goto bail;
         }
 #endif
 
@@ -260,8 +265,10 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
                 local_irq_enable();
 
         if (in_atomic() || mm == NULL) {
-                if (!user_mode(regs))
-                        return SIGSEGV;
+                if (!user_mode(regs)) {
+                        rc = SIGSEGV;
+                        goto bail;
+                }
                 /* in_atomic() in user mode is really bad,
                    as is current->mm == NULL. */
                 printk(KERN_EMERG "Page fault in user mode with "
@@ -417,9 +424,11 @@ good_area:
          */
         fault = handle_mm_fault(mm, vma, address, flags);
         if (unlikely(fault & (VM_FAULT_RETRY|VM_FAULT_ERROR))) {
-                int rc = mm_fault_error(regs, address, fault);
+                rc = mm_fault_error(regs, address, fault);
                 if (rc >= MM_FAULT_RETURN)
-                        return rc;
+                        goto bail;
+                else
+                        rc = 0;
         }
 
         /*
@@ -454,7 +463,7 @@ good_area:
         }
 
         up_read(&mm->mmap_sem);
-        return 0;
+        goto bail;
 
 bad_area:
         up_read(&mm->mmap_sem);
@@ -463,7 +472,7 @@ bad_area_nosemaphore:
         /* User mode accesses cause a SIGSEGV */
         if (user_mode(regs)) {
                 _exception(SIGSEGV, regs, code, address);
-                return 0;
+                goto bail;
         }
 
         if (is_exec && (error_code & DSISR_PROTFAULT))
@@ -471,7 +480,11 @@ bad_area_nosemaphore:
                                    " page (%lx) - exploit attempt? (uid: %d)\n",
                                    address, from_kuid(&init_user_ns, current_uid()));
 
-        return SIGSEGV;
+        rc = SIGSEGV;
+
+bail:
+        exception_exit(prev_state);
+        return rc;
 
 }