6.15-stable review patch. If anyone has any objections, please let me know.
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From: Stefan Metzmacher metze@samba.org
commit 1944f6ab4967db7ad8d4db527dceae8c77de76e9 upstream.
We should not send smbdirect_data_transfer messages larger than the negotiated max_send_size, typically 1364 bytes, which means 24 bytes of the smbdirect_data_transfer header + 1340 payload bytes.
This happened when doing an SMB2 write with more than 1340 bytes (which is done inline as it's below rdma_readwrite_threshold).
It means the peer resets the connection.
When testing between cifs.ko and ksmbd.ko something like this is logged:
client:
CIFS: VFS: RDMA transport re-established siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 siw: got TERMINATE. layer 1, type 2, code 2 CIFS: VFS: \carina Send error in SessSetup = -11 smb2_reconnect: 12 callbacks suppressed CIFS: VFS: reconnect tcon failed rc = -11 CIFS: VFS: reconnect tcon failed rc = -11 CIFS: VFS: reconnect tcon failed rc = -11 CIFS: VFS: SMB: Zero rsize calculated, using minimum value 65536
and:
CIFS: VFS: RDMA transport re-established siw: got TERMINATE. layer 1, type 2, code 2 CIFS: VFS: smbd_recv:1894 disconnected siw: got TERMINATE. layer 1, type 2, code 2
The ksmbd dmesg is showing things like:
smb_direct: Recv error. status='local length error (1)' opcode=128 smb_direct: disconnected smb_direct: Recv error. status='local length error (1)' opcode=128 ksmbd: smb_direct: disconnected ksmbd: sock_read failed: -107
As smbd_post_send_iter() limits the transmitted number of bytes we need loop over it in order to transmit the whole iter.
Reviewed-by: David Howells dhowells@redhat.com Tested-by: David Howells dhowells@redhat.com Tested-by: Meetakshi Setiya msetiya@microsoft.com Cc: Tom Talpey tom@talpey.com Cc: linux-cifs@vger.kernel.org Cc: stable+noautosel@kernel.org # sp->max_send_size should be info->max_send_size in backports Fixes: 3d78fe73fa12 ("cifs: Build the RDMA SGE list directly from an iterator") Signed-off-by: Stefan Metzmacher metze@samba.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/client/smbdirect.c | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-)
--- a/fs/smb/client/smbdirect.c +++ b/fs/smb/client/smbdirect.c @@ -907,8 +907,10 @@ wait_send_queue: .local_dma_lkey = sc->ib.pd->local_dma_lkey, .direction = DMA_TO_DEVICE, }; + size_t payload_len = umin(*_remaining_data_length, + sp->max_send_size - sizeof(*packet));
- rc = smb_extract_iter_to_rdma(iter, *_remaining_data_length, + rc = smb_extract_iter_to_rdma(iter, payload_len, &extract); if (rc < 0) goto err_dma; @@ -1013,6 +1015,27 @@ static int smbd_post_send_empty(struct s return smbd_post_send_iter(info, NULL, &remaining_data_length); }
+static int smbd_post_send_full_iter(struct smbd_connection *info, + struct iov_iter *iter, + int *_remaining_data_length) +{ + int rc = 0; + + /* + * smbd_post_send_iter() respects the + * negotiated max_send_size, so we need to + * loop until the full iter is posted + */ + + while (iov_iter_count(iter) > 0) { + rc = smbd_post_send_iter(info, iter, _remaining_data_length); + if (rc < 0) + break; + } + + return rc; +} + /* * Post a receive request to the transport * The remote peer can only send data when a receive request is posted @@ -1962,14 +1985,14 @@ int smbd_send(struct TCP_Server_Info *se klen += rqst->rq_iov[i].iov_len; iov_iter_kvec(&iter, ITER_SOURCE, rqst->rq_iov, rqst->rq_nvec, klen);
- rc = smbd_post_send_iter(info, &iter, &remaining_data_length); + rc = smbd_post_send_full_iter(info, &iter, &remaining_data_length); if (rc < 0) break;
if (iov_iter_count(&rqst->rq_iter) > 0) { /* And then the data pages if there are any */ - rc = smbd_post_send_iter(info, &rqst->rq_iter, - &remaining_data_length); + rc = smbd_post_send_full_iter(info, &rqst->rq_iter, + &remaining_data_length); if (rc < 0) break; }