io_uring/kbuf: return correct iovec count from classic buffer peek

io_provided_buffers_select() returns 0 to indicate success, but it should
be returning 1 to indicate that 1 vec was mapped. This causes peeking
to fail with classic provided buffers, and while that's not a use case
that anyone should use, it should still work correctly.

The end result is that no buffer will be selected, and hence a completion
with '0' as the result will be posted, without a buffer attached.

Fixes: 35c8711c8fc4 ("io_uring/kbuf: add helpers for getting/peeking multiple buffers")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index 1af2bd56af44ac496fd56f327e596730844ceb3f..bdfa30b38321b76f123c8d77f1e3bf47b816d9ea 100644 (file)
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -129,7 +129,7 @@ static int io_provided_buffers_select(struct io_kiocb *req, size_t *len,
 
        iov[0].iov_base = buf;
        iov[0].iov_len = *len;
-       return 0;
+       return 1;
 }
 
 static struct io_uring_buf *io_ring_head_to_buf(struct io_uring_buf_ring *br,