Commit f112a2fd authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'vfs-5.5-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux 

Pull splice fix from Darrick Wong:
 "Fix another place in the splice code where a pipe could ask a
  filesystem for a longer read than the pipe actually has free buffer
  space"

* tag 'vfs-5.5-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  splice: only read in as much information as there is pipe buffer space
parents 3b266a52 3253d9d0

fs/splice.c

+11 −3
Original line number Diff line number Diff line
@@ -945,12 +945,13 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, 
	WARN_ON_ONCE(pipe->nrbufs != 0);



	while (len) {

		unsigned int pipe_pages;

		size_t read_len;

		loff_t pos = sd->pos, prev_pos = pos;



		/* Don't try to read more the pipe has space for. */

		read_len = min_t(size_t, len,

				 (pipe->buffers - pipe->nrbufs) << PAGE_SHIFT);

		pipe_pages = pipe->buffers - pipe->nrbufs;

		read_len = min(len, (size_t)pipe_pages << PAGE_SHIFT);

		ret = do_splice_to(in, &pos, pipe, read_len, flags);

		if (unlikely(ret <= 0))

			goto out_release;
@@ -1180,8 +1181,15 @@ static long do_splice(struct file *in, loff_t __user *off_in, 


		pipe_lock(opipe);

		ret = wait_for_space(opipe, flags);

		if (!ret)

		if (!ret) {

			unsigned int pipe_pages;



			/* Don't try to read more the pipe has space for. */

			pipe_pages = opipe->buffers - opipe->nrbufs;

			len = min(len, (size_t)pipe_pages << PAGE_SHIFT);



			ret = do_splice_to(in, &offset, opipe, len, flags);

		}

		pipe_unlock(opipe);

		if (ret > 0)

			wakeup_pipe_readers(opipe);

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