From: Rik van Riel <riel@redhat.com>
Date: Mon, 26 Apr 2010 16:33:03 +0000 (-0400)
Subject: mmap: check ->vm_ops before dereferencing
X-Git-Tag: submit/tizen/20141203.153721~11902
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5892753383090a3eddf0e1b043c95e3b2c7feda5;p=platform%2Fkernel%2Flinux-arm64.git

mmap: check ->vm_ops before dereferencing

Check whether the VMA has a vm_ops before calling close, just
like we check vm_ops before calling open a few dozen lines
higher up in the function.

Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/mmap.c b/mm/mmap.c
index f90ea92f755..456ec6f2788 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1977,7 +1977,8 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
 		return 0;
 
 	/* Clean everything up if vma_adjust failed. */
-	new->vm_ops->close(new);
+	if (new->vm_ops && new->vm_ops->close)
+		new->vm_ops->close(new);
 	if (new->vm_file) {
 		if (vma->vm_flags & VM_EXECUTABLE)
 			removed_exe_file_vma(mm);