crypto: caam - fix missing dma unmap on error path

If dma mapping for dma_addr_out fails, the descriptor memory is freed
but the previous dma mapping for dma_addr_in remains.
This patch resolves the missing dma unmap and groups resource
allocations at function start.

Cc: <stable@vger.kernel.org> # 3.13+
Signed-off-by: Cristian Stoica <cristian.stoica@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/caam/key_gen.c b/drivers/crypto/caam/key_gen.c
index 871703c49d2c09923d162af7651518d46a5ff3a4..e1eaf4ff9762646acac020c85c77bb122c570f0e 100644 (file)
--- a/drivers/crypto/caam/key_gen.c
+++ b/drivers/crypto/caam/key_gen.c
@@ -48,23 +48,29 @@ int gen_split_key(struct device *jrdev, u8 *key_out, int split_key_len,
        u32 *desc;
        struct split_key_result result;
        dma_addr_t dma_addr_in, dma_addr_out;
-       int ret = 0;
+       int ret = -ENOMEM;
 
        desc = kmalloc(CAAM_CMD_SZ * 6 + CAAM_PTR_SZ * 2, GFP_KERNEL | GFP_DMA);
        if (!desc) {
                dev_err(jrdev, "unable to allocate key input memory\n");
-               return -ENOMEM;
+               return ret;
        }
 
-       init_job_desc(desc, 0);
-
        dma_addr_in = dma_map_single(jrdev, (void *)key_in, keylen,
                                     DMA_TO_DEVICE);
        if (dma_mapping_error(jrdev, dma_addr_in)) {
                dev_err(jrdev, "unable to map key input memory\n");
-               kfree(desc);
-               return -ENOMEM;
+               goto out_free;
        }
+
+       dma_addr_out = dma_map_single(jrdev, key_out, split_key_pad_len,
+                                     DMA_FROM_DEVICE);
+       if (dma_mapping_error(jrdev, dma_addr_out)) {
+               dev_err(jrdev, "unable to map key output memory\n");
+               goto out_unmap_in;
+       }
+
+       init_job_desc(desc, 0);
        append_key(desc, dma_addr_in, keylen, CLASS_2 | KEY_DEST_CLASS_REG);
 
        /* Sets MDHA up into an HMAC-INIT */
@@ -81,13 +87,6 @@ int gen_split_key(struct device *jrdev, u8 *key_out, int split_key_len,
         * FIFO_STORE with the explicit split-key content store
         * (0x26 output type)
         */
-       dma_addr_out = dma_map_single(jrdev, key_out, split_key_pad_len,
-                                     DMA_FROM_DEVICE);
-       if (dma_mapping_error(jrdev, dma_addr_out)) {
-               dev_err(jrdev, "unable to map key output memory\n");
-               kfree(desc);
-               return -ENOMEM;
-       }
        append_fifo_store(desc, dma_addr_out, split_key_len,
                          LDST_CLASS_2_CCB | FIFOST_TYPE_SPLIT_KEK);
 
@@ -115,10 +114,10 @@ int gen_split_key(struct device *jrdev, u8 *key_out, int split_key_len,
 
        dma_unmap_single(jrdev, dma_addr_out, split_key_pad_len,
                         DMA_FROM_DEVICE);
+out_unmap_in:
        dma_unmap_single(jrdev, dma_addr_in, keylen, DMA_TO_DEVICE);
-
+out_free:
        kfree(desc);
-
        return ret;
 }
 EXPORT_SYMBOL(gen_split_key);