commit ba87977a49 upstream.
Commit b7ce40cff0 ("kernfs: cache atomic_write_len in
kernfs_open_file") changes type of local variable 'len' from ssize_t
to size_t. This change caused that the *ppos value is updated also
when the previous write callback failed.
Mentioned snippet:
...
len = ops->write(...); <- return value can be negative
...
if (len > 0) <- true here in this case
*ppos += len;
...
Fixes: b7ce40cff0 ("kernfs: cache atomic_write_len in kernfs_open_file")
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
650d3d8512