[PATCH] [v2] crypto: ccp - fix memleak in ccp_init_dm_workarea

[Dinghao Liu]

When dma_map_single() fails, wa->address is supposed to be freed
by the callers of ccp_init_dm_workarea() through ccp_dm_free().
However, many of the call spots don't expect to have to call
ccp_dm_free() on failure of ccp_init_dm_workarea(), which may
lead to a memleak. Let's free wa->address in ccp_init_dm_workarea()
when dma_map_single() fails.

Fixes: 63b945091a07 ("crypto: ccp - CCP device driver and interface support")
Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
---

Changelog:

v2: -Improve the commit message.
    -Set wa->address to NULL after kfree() to prevent double-free.
---
 drivers/crypto/ccp/ccp-ops.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
index aa4e1a500691..cb8e99936abb 100644
--- a/drivers/crypto/ccp/ccp-ops.c
+++ b/drivers/crypto/ccp/ccp-ops.c
@@ -179,8 +179,11 @@ static int ccp_init_dm_workarea(struct ccp_dm_workarea *wa,
 
 		wa->dma.address = dma_map_single(wa->dev, wa->address, len,
 						 dir);
-		if (dma_mapping_error(wa->dev, wa->dma.address))
+		if (dma_mapping_error(wa->dev, wa->dma.address)) {
+			kfree(wa->address);
+			wa->address = NULL;
 			return -ENOMEM;
+		}
 
 		wa->dma.length = len;
 	}
-- 
2.17.1