Merge tag '6.12rc-more-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull xmb client fixes from Steve French:

 - Noisy log message cleanup

 - Important netfs fix for cifs crash in generic/074

 - Three minor improvements to use of hashing (multichannel and mount
   improvements)

 - Fix decryption crash for large read with small esize

* tag '6.12rc-more-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: make SHA-512 TFM ephemeral
  smb: client: make HMAC-MD5 TFM ephemeral
  smb: client: stop flooding dmesg in smb2_calc_signature()
  smb: client: allocate crypto only for primary server
  smb: client: fix UAF in async decryption
  netfs: Fix write oops in generic/346 (9p) and generic/074 (cifs)

1 files changed, 11 insertions, 1 deletions

diff --git a/fs/netfs/write_issue.c b/fs/netfs/write_issue.c
index 04e66d587f77..0929d9fd4ce7 100644
--- a/fs/netfs/write_issue.c
+++ b/fs/netfs/write_issue.c
@@ -153,12 +153,22 @@ static void netfs_prepare_write(struct netfs_io_request *wreq,
 				loff_t start)
 {
 	struct netfs_io_subrequest *subreq;
+	struct iov_iter *wreq_iter = &wreq->io_iter;
+
+	/* Make sure we don't point the iterator at a used-up folio_queue
+	 * struct being used as a placeholder to prevent the queue from
+	 * collapsing.  In such a case, extend the queue.
+	 */
+	if (iov_iter_is_folioq(wreq_iter) &&
+	    wreq_iter->folioq_slot >= folioq_nr_slots(wreq_iter->folioq)) {
+		netfs_buffer_make_space(wreq);
+	}
 
 	subreq = netfs_alloc_subrequest(wreq);
 	subreq->source		= stream->source;
 	subreq->start		= start;
 	subreq->stream_nr	= stream->stream_nr;
-	subreq->io_iter		= wreq->io_iter;
+	subreq->io_iter		= *wreq_iter;
 
 	_enter("R=%x[%x]", wreq->debug_id, subreq->debug_index);