mm/mmap.c:insert_vm_struct(): check for failure before setting values
There's no point in initializing vma->vm_pgoff if the insertion attempt
will be failing anyway. Run the checks before performing the
initialization.
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mmap.c b/mm/mmap.c
index 7a3b123..b6be324 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2871,6 +2871,13 @@
struct vm_area_struct *prev;
struct rb_node **rb_link, *rb_parent;
+ if (find_vma_links(mm, vma->vm_start, vma->vm_end,
+ &prev, &rb_link, &rb_parent))
+ return -ENOMEM;
+ if ((vma->vm_flags & VM_ACCOUNT) &&
+ security_vm_enough_memory_mm(mm, vma_pages(vma)))
+ return -ENOMEM;
+
/*
* The vm_pgoff of a purely anonymous vma should be irrelevant
* until its first write fault, when page's anon_vma and index
@@ -2887,12 +2894,6 @@
BUG_ON(vma->anon_vma);
vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
}
- if (find_vma_links(mm, vma->vm_start, vma->vm_end,
- &prev, &rb_link, &rb_parent))
- return -ENOMEM;
- if ((vma->vm_flags & VM_ACCOUNT) &&
- security_vm_enough_memory_mm(mm, vma_pages(vma)))
- return -ENOMEM;
vma_link(mm, vma, prev, rb_link, rb_parent);
return 0;