[PATCH] fs: sendfile handles O_NONBLOCK of out_fd

[Andrei Vagin <avagin@gmail.com>]

sendfile has to return EAGAIN if out_fd is nonblocking and the write
into it would block.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Fixes: b964bf53e540 ("teach sendfile(2) to handle send-to-pipe directly")
Signed-off-by: Andrei Vagin <avagin@gmail.com>
---
 fs/read_write.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/read_write.c b/fs/read_write.c
index e643aec2b0ef..ee59419cbf0f 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1247,6 +1247,9 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 					  count, fl);
 		file_end_write(out.file);
 	} else {
+		if (out.file->f_flags & O_NONBLOCK)
+			fl |= SPLICE_F_NONBLOCK;
+
 		retval = splice_file_to_pipe(in.file, opipe, &pos, count, fl);
 	}
 
-- 
2.35.1