[PATCH 4.9 01/22] vfs: fix uninitialized flags in splice_to_pipe()

From: Greg Kroah-Hartman
Date: Tue Feb 21 2017 - 08:04:05 EST

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


From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

commit 5a81e6a171cdbd1fa8bc1fdd80c23d3d71816fac upstream.

Flags (PIPE_BUF_FLAG_PACKET, PIPE_BUF_FLAG_GIFT) could remain on the
unused part of the pipe ring buffer. Previously splice_to_pipe() left
the flags value alone, which could result in incorrect behavior.

Uninitialized flags appears to have been there from the introduction of
the splice syscall.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

fs/splice.c | 1 +
1 file changed, 1 insertion(+)

--- a/fs/splice.c
+++ b/fs/splice.c
@@ -203,6 +203,7 @@ ssize_t splice_to_pipe(struct pipe_inode
buf->len = spd->partial[page_nr].len;
buf->private = spd->partial[page_nr].private;
buf->ops = spd->ops;
+ buf->flags = 0;