2014-10-30 12:41:40

by Cristian Stoica

Subject: [PATCH] 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: <[email protected]> # 3.13+
Signed-off-by: Cristian Stoica <[email protected]>
---
drivers/crypto/caam/key_gen.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/drivers/crypto/caam/key_gen.c b/drivers/crypto/caam/key_gen.c
index 871703c..e1eaf4f 100644
--- 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);
--
1.8.3.1

2014-11-06 15:13:26

by Herbert Xu

Subject: Re: [PATCH] crypto: caam: fix missing dma unmap on error path

On Thu, Oct 30, 2014 at 02:40:22PM +0200, Cristian Stoica wrote:
> 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: <[email protected]> # 3.13+
> Signed-off-by: Cristian Stoica <[email protected]>

Patch applied to crypto.

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt