@@ -814,17 +814,15 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
{
struct pipe_inode_info *pipe;
long ret, bytes;
- umode_t i_mode;
size_t len;
int i, flags, more;
/*
- * We require the input being a regular file, as we don't want to
- * randomly drop data for eg socket -> socket splicing. Use the
- * piped splicing for that!
+ * We require the input to be seekable, as we don't want to randomly
+ * drop data for eg socket -> socket splicing. Use the piped splicing
+ * for that!
*/
- i_mode = file_inode(in)->i_mode;
- if (unlikely(!S_ISREG(i_mode) && !S_ISBLK(i_mode)))
+ if (unlikely(!(in->f_mode & FMODE_LSEEK)))
return -EINVAL;
/*
The original direct splicing mechanism from Jens required the input to be a regular file because it was avoiding the special socket case. It also recognized blkdevs as being close enough to a regular file. But it forgot about chardevs, which behave the same way and work fine here. This is an okayish heuristic, but it doesn't totally work. For example, a few chardevs should be spliceable here. And a few regular files shouldn't. This patch fixes this by instead checking whether FMODE_LSEEK is set, which represents decently enough what we need rewinding for when splicing to internal pipes. Fixes: b92ce5589374 ("[PATCH] splice: add direct fd <-> fd splicing support") Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> --- fs/splice.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)