--- /dev/null
+From 5df63c2a149ae65a9ec239e7c2af44efa6f79beb Mon Sep 17 00:00:00 2001
+From: Mike Kravetz <mike.kravetz@oracle.com>
+Date: Thu, 5 Apr 2018 16:18:21 -0700
+Subject: hugetlbfs: fix bug in pgoff overflow checking
+
+From: Mike Kravetz <mike.kravetz@oracle.com>
+
+commit 5df63c2a149ae65a9ec239e7c2af44efa6f79beb upstream.
+
+This is a fix for a regression in 32 bit kernels caused by an invalid
+check for pgoff overflow in hugetlbfs mmap setup. The check incorrectly
+specified that the size of a loff_t was the same as the size of a long.
+The regression prevents mapping hugetlbfs files at offsets greater than
+4GB on 32 bit kernels.
+
+On 32 bit kernels conversion from a page based unsigned long can not
+overflow a loff_t byte offset. Therefore, skip this check if
+sizeof(unsigned long) != sizeof(loff_t).
+
+Link: http://lkml.kernel.org/r/20180330145402.5053-1-mike.kravetz@oracle.com
+Fixes: 63489f8e8211 ("hugetlbfs: check for pgoff value overflow")
+Reported-by: Dan Rue <dan.rue@linaro.org>
+Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
+Tested-by: Anders Roxell <anders.roxell@linaro.org>
+Cc: Michal Hocko <mhocko@kernel.org>
+Cc: Yisheng Xie <xieyisheng1@huawei.com>
+Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
+Cc: Nic Losby <blurbdust@gmail.com>
+Cc: <stable@vger.kernel.org>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/hugetlbfs/inode.c | 10 +++++++---
+ 1 file changed, 7 insertions(+), 3 deletions(-)
+
+--- a/fs/hugetlbfs/inode.c
++++ b/fs/hugetlbfs/inode.c
+@@ -148,10 +148,14 @@ static int hugetlbfs_file_mmap(struct fi
+
+ /*
+ * page based offset in vm_pgoff could be sufficiently large to
+- * overflow a (l)off_t when converted to byte offset.
++ * overflow a loff_t when converted to byte offset. This can
++ * only happen on architectures where sizeof(loff_t) ==
++ * sizeof(unsigned long). So, only check in those instances.
+ */
+- if (vma->vm_pgoff & PGOFF_LOFFT_MAX)
+- return -EINVAL;
++ if (sizeof(unsigned long) == sizeof(loff_t)) {
++ if (vma->vm_pgoff & PGOFF_LOFFT_MAX)
++ return -EINVAL;
++ }
+
+ /* must be huge page aligned */
+ if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT))