xtensa: fix potential NULL-pointer dereference

Add missing check for memory allocation fail.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/xtensa/include/asm/pgalloc.h b/arch/xtensa/include/asm/pgalloc.h
index cf914c8c249a..037671a655dc 100644
--- a/arch/xtensa/include/asm/pgalloc.h
+++ b/arch/xtensa/include/asm/pgalloc.h
@@ -51,9 +51,13 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
                                         unsigned long addr)
 {
+        pte_t *pte;
         struct page *page;
 
-        page = virt_to_page(pte_alloc_one_kernel(mm, addr));
+        pte = pte_alloc_one_kernel(mm, addr);
+        if (!pte)
+                return NULL;
+        page = virt_to_page(pte);
         pgtable_page_ctor(page);
         return page;
 }