Merge v6.18.19linux-rolling-lts

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 11 insertions, 2 deletions

diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index 308ef71bcb28..09b62d3224f1 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -111,9 +111,18 @@ bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
 
 	buf = req->kbuf;
 	bl = io_buffer_get_list(ctx, buf->bgid);
-	list_add(&buf->list, &bl->buf_list);
-	bl->nbufs++;
+	/*
+	 * If the buffer list was upgraded to a ring-based one, or removed,
+	 * while the request was in-flight in io-wq, drop it.
+	 */
+	if (bl && !(bl->flags & IOBL_BUF_RING)) {
+		list_add(&buf->list, &bl->buf_list);
+		bl->nbufs++;
+	} else {
+		kfree(buf);
+	}
 	req->flags &= ~REQ_F_BUFFER_SELECTED;
+	req->kbuf = NULL;
 
 	io_ring_submit_unlock(ctx, issue_flags);
 	return true;