[PATCH 5.16 0250/1017] crypto: ccp - ccp_dmaengine_unregister release dma channels

From: Greg Kroah-Hartman
Date: Tue Apr 05 2022 - 07:44:58 EST


From: Dāvis Mosāns <davispuh@xxxxxxxxx>

[ Upstream commit 54cce8ecb9254f971b40a72911c6da403720a2d2 ]

ccp_dmaengine_register adds dma_chan->device_node to dma_dev->channels list
but ccp_dmaengine_unregister didn't remove them.
That can cause crashes in various dmaengine methods that tries to use dma_dev->channels

Fixes: 58ea8abf4904 ("crypto: ccp - Register the CCP as a DMA...")
Signed-off-by: Dāvis Mosāns <davispuh@xxxxxxxxx>
Acked-by: John Allen <john.allen@xxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/crypto/ccp/ccp-dmaengine.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/crypto/ccp/ccp-dmaengine.c b/drivers/crypto/ccp/ccp-dmaengine.c
index d718db224be4..7d4b4ad1db1f 100644
--- a/drivers/crypto/ccp/ccp-dmaengine.c
+++ b/drivers/crypto/ccp/ccp-dmaengine.c
@@ -632,6 +632,20 @@ static int ccp_terminate_all(struct dma_chan *dma_chan)
return 0;
}

+static void ccp_dma_release(struct ccp_device *ccp)
+{
+ struct ccp_dma_chan *chan;
+ struct dma_chan *dma_chan;
+ unsigned int i;
+
+ for (i = 0; i < ccp->cmd_q_count; i++) {
+ chan = ccp->ccp_dma_chan + i;
+ dma_chan = &chan->dma_chan;
+ tasklet_kill(&chan->cleanup_tasklet);
+ list_del_rcu(&dma_chan->device_node);
+ }
+}
+
int ccp_dmaengine_register(struct ccp_device *ccp)
{
struct ccp_dma_chan *chan;
@@ -736,6 +750,7 @@ int ccp_dmaengine_register(struct ccp_device *ccp)
return 0;

err_reg:
+ ccp_dma_release(ccp);
kmem_cache_destroy(ccp->dma_desc_cache);

err_cache:
@@ -752,6 +767,7 @@ void ccp_dmaengine_unregister(struct ccp_device *ccp)
return;

dma_async_device_unregister(dma_dev);
+ ccp_dma_release(ccp);

kmem_cache_destroy(ccp->dma_desc_cache);
kmem_cache_destroy(ccp->dma_cmd_cache);
--
2.34.1