From ae9e9c6aeea6f91ccb4fb369d7dd8f1a8b5f6a58 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 30 Oct 2014 10:53:17 -0400 Subject: [PATCH] ext4: make ext4_ext_convert_to_initialized() return proper number of blocks ext4_ext_convert_to_initialized() can return more blocks than are actually allocated from map->m_lblk in case where initial part of the on-disk extent is zeroed out. Luckily this doesn't have serious consequences because the caller currently uses the return value only to unmap metadata buffers. Anyway this is a data corruption/exposure problem waiting to happen so fix it. Coverity-id: 1226848 Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o --- fs/ext4/extents.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 37043d0b2be8..0b16fb4c06d3 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3603,11 +3603,10 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, } } - allocated = ext4_split_extent(handle, inode, ppath, - &split_map, split_flag, flags); - if (allocated < 0) - err = allocated; - + err = ext4_split_extent(handle, inode, ppath, &split_map, split_flag, + flags); + if (err > 0) + err = 0; out: /* If we have gotten a failure, don't zero out status tree */ if (!err)