From c8d152b8c1968d3fcc5ce059225fef40dec4bca9 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 25 Jun 2025 10:17:06 -0600 Subject: [PATCH] io_uring/net: mark iov as dynamically allocated even for single segments Commit 9a709b7e98e6fa51600b5f2d24c5068efa6d39de upstream. A bigger array of vecs could've been allocated, but io_ring_buffers_peek() still decided to cap the mapped range depending on how much data was available. Hence don't rely on the segment count to know if the request should be marked as needing cleanup, always check upfront if the iov array is different than the fast_iov array. Fixes: 26ec15e4b0c1 ("io_uring/kbuf: don't truncate end buffer for multiple buffer peeks") Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/net.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/io_uring/net.c b/io_uring/net.c index d18b751eb812..5db69a45dac5 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -1118,6 +1118,12 @@ static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg if (unlikely(ret < 0)) return ret; + if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) { + kmsg->free_iov_nr = ret; + kmsg->free_iov = arg.iovs; + req->flags |= REQ_F_NEED_CLEANUP; + } + /* special case 1 vec, can be a fast path */ if (ret == 1) { sr->buf = arg.iovs[0].iov_base; @@ -1126,11 +1132,6 @@ static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg } iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret, arg.out_len); - if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) { - kmsg->free_iov_nr = ret; - kmsg->free_iov = arg.iovs; - req->flags |= REQ_F_NEED_CLEANUP; - } } else { void __user *buf;