On 10/05/2017 03:01 PM, Bruce Richardson wrote:
On Thu, Oct 05, 2017 at 02:42:24PM +0200, Maxime Coquelin wrote:
On 10/05/2017 02:35 PM, Piasecki, JacekX wrote:
-----Original Message-----
From: Maxime Coquelin [mailto:maxime.coque...@redhat.com]
Sent: Monday, 2 October, 2017 17:07
To: Jastrzebski, MichalX K <michalx.k.jastrzeb...@intel.com>;
y...@fridaylinux.org
Cc: dev@dpdk.org; Jain, Deepak K <deepak.k.j...@intel.com>; Piasecki, JacekX
<jacekx.piase...@intel.com>; Liu, Changpeng <changpeng....@intel.com>; sta...@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] examples/vhost_scsi: fix buffer not terminated
On 10/02/2017 03:50 PM, Jastrzebski, MichalX K wrote:
-----Original Message-----
From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Michal
Jastrzebski
Sent: Friday, September 22, 2017 3:08 PM
To: y...@fridaylinux.org; maxime.coque...@redhat.com
Cc: dev@dpdk.org; Jain, Deepak K <deepak.k.j...@intel.com>; Piasecki,
JacekX <jacekx.piase...@intel.com>; Liu, Changpeng
<changpeng....@intel.com>; sta...@dpdk.org
Subject: [dpdk-dev] [PATCH] examples/vhost_scsi: fix buffer not
terminated
From: Jacek Piasecki <jacekx.piase...@intel.com>
Fix size of buffer in strcpy. There was possible to get not
terminated string after copy operation.
Coverity issue: 158631
Fixes: db75c7af19bb ("examples/vhost_scsi: introduce a new sample
app")
Cc: changpeng....@intel.com
Cc: sta...@dpdk.org
Signed-off-by: Jacek Piasecki <jacekx.piase...@intel.com>
---
examples/vhost_scsi/scsi.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/examples/vhost_scsi/scsi.c b/examples/vhost_scsi/scsi.c
index 54d3104..de9639a 100644
--- a/examples/vhost_scsi/scsi.c
+++ b/examples/vhost_scsi/scsi.c
@@ -307,7 +307,8 @@
strncpy((char *)inqdata->t10_vendor_id, "INTEL", 8);
/* PRODUCT IDENTIFICATION */
- strncpy((char *)inqdata->product_id, bdev->product_name,
16);
+ strncpy((char *)inqdata->product_id, bdev->product_name,
+ ARRAY_SIZE(inqdata->product_id) - 1);
Does it assume that product_id is memzero'ed before?
IIUC strncpy manpage, it wouldn't protect against non-null terminated strings
if it is not the case:
Yes, I assumed that this area is zeroed before strncpy. Earlier there is a
casting from *task to *inqdata (*task is zmalloced).
Ok. I think the assumption is dangerous.
To be sure that the destination area is clear I propose to add:
memset(inqdata->product_id, 0, ARRAY_SIZE(inqdata->product_id));
before strncpy. Would that be OK?
Or call strncpy with ARRAY_SIZE(inqdata->product_id) as max length,
and then do
inqdata->product_id[ARRAY_SIZE(inqdata->product_id) - 1] = '\0';
Regards,
Maxime
Or use snprintf instead of strncpy, as we do in many places in DPDK.
Still only one line of code, with nice null-termination, and truncation
semantics.
+1
/Bruce
