[3.13.y-ckt stable] Patch "crypto: caam - fix missing dma unmap on error path" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    crypto: caam - fix missing dma unmap on error path

to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11-ckt12.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 57241397ff521b8d1c8770f1e557cc4642fcc4e2 Mon Sep 17 00:00:00 2001
From: Cristian Stoica <cristian.stoica at freescale.com>
Date: Thu, 30 Oct 2014 14:40:22 +0200
Subject: crypto: caam - fix missing dma unmap on error path

commit 738459e3f88538f2ece263424dafe5d91799e46b upstream.

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.

Signed-off-by: Cristian Stoica <cristian.stoica at freescale.com>
Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 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 ea2e406..b872eed 100644
--- a/drivers/crypto/caam/key_gen.c
+++ b/drivers/crypto/caam/key_gen.c
@@ -51,23 +51,29 @@ 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 */
@@ -84,13 +90,6 @@ 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);

@@ -118,10 +117,10 @@ 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);
--
1.9.1