powerpc: kernel/kgdb.c: Fix memory leakage

the variable backup_current_thread_info isn't freed before existing the
function.

Signed-off-by: Cong Ding <dinggnu@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index c470a40b29f5..a7bc7521c064 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -154,12 +154,12 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
 static int kgdb_singlestep(struct pt_regs *regs)
 {
         struct thread_info *thread_info, *exception_thread_info;
-        struct thread_info *backup_current_thread_info = \
-                (struct thread_info *)kmalloc(sizeof(struct thread_info), GFP_KERNEL);
+        struct thread_info *backup_current_thread_info;
 
         if (user_mode(regs))
                 return 0;
 
+        backup_current_thread_info = (struct thread_info *)kmalloc(sizeof(struct thread_info), GFP_KERNEL);
         /*
          * On Book E and perhaps other processors, singlestep is handled on
          * the critical exception stack.  This causes current_thread_info()
@@ -185,6 +185,7 @@ static int kgdb_singlestep(struct pt_regs *regs)
                 /* Restore current_thread_info lastly. */
                 memcpy(exception_thread_info, backup_current_thread_info, sizeof *thread_info);
 
+        kfree(backup_current_thread_info);
         return 1;
 }