[PATCH 3.10 28/29] btrfs: incorrect handling for fiemap_fill_next_extent return

From: Greg Kroah-Hartman
Date: Fri Jun 19 2015 - 16:51:52 EST


3.10-stable review patch. If anyone has any objections, please let me know.

------------------

From: Chengyu Song <csong84@xxxxxxxxxx>

commit 26e726afe01c1c82072cf23a5ed89ce25f39d9f2 upstream.

fiemap_fill_next_extent returns 0 on success, -errno on error, 1 if this was
the last extent that will fit in user array. If 1 is returned, the return
value may eventually returned to user space, which should not happen, according
to manpage of ioctl.

Signed-off-by: Chengyu Song <csong84@xxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxx>
Reviewed-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
Signed-off-by: Chris Mason <clm@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/btrfs/extent_io.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4080,8 +4080,11 @@ int extent_fiemap(struct inode *inode, s
}
ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
em_len, flags);
- if (ret)
+ if (ret) {
+ if (ret == 1)
+ ret = 0;
goto out_free;
+ }
}
out_free:
free_extent_map(em);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at http://www.tux.org/lkml/