fat: mmu_private race fix

mmu_private is 64bits value, hence it's not atomic to update.

So, the access rule for mmu_private is we must hold ->i_mutex.  But,
fat_get_block() path doesn't follow the rule on non-allocation path.

This fixes by using i_size instead if non-allocation path.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 140fc39e2307..2ecaa17acdb5 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -77,7 +77,7 @@ next:
 
         *bh = NULL;
         iblock = *pos >> sb->s_blocksize_bits;
-        err = fat_bmap(dir, iblock, &phys, &mapped_blocks);
+        err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0);
         if (err || !phys)
                 return -1;      /* beyond EOF or error */