From: Jens Axboe axboe@kernel.dk
commit 16c8d2df7ec0eed31b7d3b61cb13206a7fb930cc upstream.
When setting up the next segment, we check what type the iter is and handle it accordingly. However, when incrementing and processed amount we do not, and both iter advance and addr/len are adjusted, regardless of type. Split the increment side just like we do on the setup side.
Fixes: 4017eb91a9e7 ("io_uring: make loop_rw_iter() use original user supplied pointers") Cc: stable@vger.kernel.org Reported-by: Valentina Palmiotti vpalmiotti@gmail.com Reviewed-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/io_uring.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
--- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3206,12 +3206,15 @@ static ssize_t loop_rw_iter(int rw, stru ret = nr; break; } + if (!iov_iter_is_bvec(iter)) { + iov_iter_advance(iter, nr); + } else { + req->rw.len -= nr; + req->rw.addr += nr; + } ret += nr; if (nr != iovec.iov_len) break; - req->rw.len -= nr; - req->rw.addr += nr; - iov_iter_advance(iter, nr); }
return ret;