[PATCH 4.11 060/114] orangefs: do not check possibly stale size on truncate

From: Greg Kroah-Hartman
Date: Thu May 18 2017 - 06:51:36 EST


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

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

From: Martin Brandenburg <martin@xxxxxxxxxxxx>

commit 53950ef541675df48c219a8d665111a0e68dfc2f upstream.

Let the server figure this out because our size might be out of date or
not present.

The bug was that

xfs_io -f -t -c "pread -v 0 100" /mnt/foo
echo "Test" > /mnt/foo
xfs_io -f -t -c "pread -v 0 100" /mnt/foo

fails because the second truncate did not happen if nothing had
requested the size after the write in echo. Thus i_size was zero (not
present) and the orangefs_setattr though i_size was zero and there was
nothing to do.

Signed-off-by: Martin Brandenburg <martin@xxxxxxxxxxxx>
Signed-off-by: Mike Marshall <hubcap@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/orangefs/inode.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -218,8 +218,7 @@ int orangefs_setattr(struct dentry *dent
if (ret)
goto out;

- if ((iattr->ia_valid & ATTR_SIZE) &&
- iattr->ia_size != i_size_read(inode)) {
+ if (iattr->ia_valid & ATTR_SIZE) {
ret = orangefs_setattr_size(inode, iattr);
if (ret)
goto out;