From 31ccd1ba20d8007e13f0b3175b7c394d900759f2 Mon Sep 17 00:00:00 2001 From: Nick Child Date: Wed, 9 Aug 2023 17:10:36 -0500 Subject: [PATCH] ibmvnic: Handle DMA unmapping of login buffs in release functions commit d78a671eb8996af19d6311ecdee9790d2fa479f0 upstream. Rather than leaving the DMA unmapping of the login buffers to the login response handler, move this work into the login release functions. Previously, these functions were only used for freeing the allocated buffers. This could lead to issues if there are more than one outstanding login buffer requests, which is possible if a login request times out. If a login request times out, then there is another call to send login. The send login function makes a call to the login buffer release function. In the past, this freed the buffers but did not DMA unmap. Therefore, the VIOS could still write to the old login (now freed) buffer. It is for this reason that it is a good idea to leave the DMA unmap call to the login buffers release function. Since the login buffer release functions now handle DMA unmapping, remove the duplicate DMA unmapping in handle_login_rsp(). Fixes: dff515a3e71d ("ibmvnic: Harden device login requests") Signed-off-by: Nick Child Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20230809221038.51296-3-nnac123@linux.ibm.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/ibm/ibmvnic.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index b55c7fc7d2e0a..4dd6c4bfd55ec 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -1397,12 +1397,22 @@ static int ibmvnic_login(struct net_device *netdev) static void release_login_buffer(struct ibmvnic_adapter *adapter) { + if (!adapter->login_buf) + return; + + dma_unmap_single(&adapter->vdev->dev, adapter->login_buf_token, + adapter->login_buf_sz, DMA_TO_DEVICE); kfree(adapter->login_buf); adapter->login_buf = NULL; } static void release_login_rsp_buffer(struct ibmvnic_adapter *adapter) { + if (!adapter->login_rsp_buf) + return; + + dma_unmap_single(&adapter->vdev->dev, adapter->login_rsp_buf_token, + adapter->login_rsp_buf_sz, DMA_FROM_DEVICE); kfree(adapter->login_rsp_buf); adapter->login_rsp_buf = NULL; } @@ -5207,11 +5217,6 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq, } adapter->login_pending = false; - dma_unmap_single(dev, adapter->login_buf_token, adapter->login_buf_sz, - DMA_TO_DEVICE); - dma_unmap_single(dev, adapter->login_rsp_buf_token, - adapter->login_rsp_buf_sz, DMA_FROM_DEVICE); - /* If the number of queues requested can't be allocated by the * server, the login response will return with code 1. We will need * to resend the login buffer with fewer queues requested.