From c3a690240423fc4eb8a0c3c7df025d13eadf140b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 10 Oct 2016 13:26:27 -0400 Subject: fix ITER_PIPE interaction with direct_IO by making sure we call iov_iter_advance() on original iov_iter even if direct_IO (done on its copy) has returned 0. It's a no-op for old iov_iter flavours and does the right thing (== truncation of the stuff we'd allocated, but not filled) in ITER_PIPE case. Failures (e.g. -EIO) get caught and dealt with by cleanup in generic_file_read_iter(). Signed-off-by: Al Viro --- fs/splice.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) (limited to 'fs/splice.c') diff --git a/fs/splice.c b/fs/splice.c index aa38901a4f10..153d4f3bd441 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -315,15 +315,9 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, *ppos = kiocb.ki_pos; file_accessed(in); } else if (ret < 0) { - if (WARN_ON(to.idx != idx || to.iov_offset)) { - /* - * a bogus ->read_iter() has copied something and still - * returned an error instead of a short read. - */ - to.idx = idx; - to.iov_offset = 0; - iov_iter_advance(&to, 0); /* to free what was emitted */ - } + to.idx = idx; + to.iov_offset = 0; + iov_iter_advance(&to, 0); /* to free what was emitted */ /* * callers of ->splice_read() expect -EAGAIN on * "can't put anything in there", rather than -EFAULT. -- cgit v1.2.3-59-g8ed1b