Merge tag 'io_uring-6.18-20251128' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

Pull io_uring fixes from Jens Axboe:

 - Ensure that vectored registered buffer imports ties the lifetime of
   those to the zero-copy send notification, not the parent request

 - Fix a bug introduced in this merge window, with the introduction of
   mixed sized CQE support

* tag 'io_uring-6.18-20251128' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
  io_uring: fix mixed cqe overflow handling
  io_uring/net: ensure vectored buffer node import is tied to notification

Author: torvalds

io_uring/io_uring.c

@@ -634,6 +634,8 @@ static void __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool dying)
 			is_cqe32 = true;
 			cqe_size <<= 1;
 		}
+		if (ctx->flags & IORING_SETUP_CQE32)
+			is_cqe32 = false;
 
 		if (!dying) {
 			if (!io_get_cqe_overflow(ctx, &cqe, true, is_cqe32))

io_uring/net.c

@@ -1532,8 +1532,10 @@ int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
 		unsigned uvec_segs = kmsg->msg.msg_iter.nr_segs;
 		int ret;
 
-		ret = io_import_reg_vec(ITER_SOURCE, &kmsg->msg.msg_iter, req,
-					&kmsg->vec, uvec_segs, issue_flags);
+		sr->notif->buf_index = req->buf_index;
+		ret = io_import_reg_vec(ITER_SOURCE, &kmsg->msg.msg_iter,
+					sr->notif, &kmsg->vec, uvec_segs,
+					issue_flags);
 		if (unlikely(ret))
 			return ret;
 		req->flags &= ~REQ_F_IMPORT_BUFFER;