From: Tadeusz Struk <tadeusz.struk@intel.com>
Date: Tue, 14 Oct 2014 01:24:26 +0000 (-0700)
Subject: crypto: qat - Prevent dma mapping zero length assoc data
X-Git-Tag: v3.17.4~110
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=63c18e716606448a3db6535e5408b34b447a92a9;p=thirdparty%2Fkernel%2Fstable.git

crypto: qat - Prevent dma mapping zero length assoc data

commit 923a6e5e5f171317ac8bb462ac4b814fa7880d3c upstream.

Do not attempt to dma map associated data if it is zero length.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Tested-by: Nikolay Aleksandrov <nikolay@redhat.com>
Reviewed-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c
index 59df488729559..5b158ca898378 100644
--- a/drivers/crypto/qat/qat_common/qat_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_algs.c
@@ -650,6 +650,8 @@ static int qat_alg_sgl_to_bufl(struct qat_crypto_instance *inst,
 		goto err;
 
 	for_each_sg(assoc, sg, assoc_n, i) {
+		if (!sg->length)
+			continue;
 		bufl->bufers[bufs].addr = dma_map_single(dev,
 							 sg_virt(sg),
 							 sg->length,