[dpdk-dev,v6] af_packet: Fix some klocwork errors

Message ID 1425958188-25041-1-git-send-email-changchun.ouyang@intel.com (mailing list archive)
State Superseded, archived
Headers

Commit Message

Ouyang Changchun March 10, 2015, 3:29 a.m. UTC
  Fix possible memory leak issue: free kvlist before return;
Fix possible resource lost issue: close qssockfd before return;

Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
---
Change in v6:
  - Refine exit point;

Change in v5:
  - Initialize qsockfd with -1;
 
Change in v4:
  - Check sockfd in internals->rx_queue against 0.
 
Change in v3:
  - Also close sockets for all queues.
 
Change in v2:
  - Make the error exit point a common path.

 lib/librte_pmd_af_packet/rte_eth_af_packet.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)
  

Comments

Wodkowski, PawelX March 10, 2015, 8:36 a.m. UTC | #1
> -
> -	return 0;
> +exit:
> +	if (kvlist != NULL)

No need for if(). This part was fine previous patch.

> +		rte_kvargs_free(kvlist);
> +	return ret;
>   }
>
>   static struct rte_driver pmd_af_packet_drv = {
>
  
Ouyang Changchun March 10, 2015, 8:49 a.m. UTC | #2
> -----Original Message-----

> From: Wodkowski, PawelX

> Sent: Tuesday, March 10, 2015 4:37 PM

> To: Ouyang, Changchun; dev@dpdk.org

> Cc: linville@tuxdriver.com; nhorman@tuxdriver.com

> Subject: Re: [PATCH v6] af_packet: Fix some klocwork errors

> 

> > -

> > -	return 0;

> > +exit:

> > +	if (kvlist != NULL)

> 

> No need for if(). This part was fine previous patch.

>


If kvlist is NULL, no reason to call rte_kvargs_free to free it.
So, adding this test is better.
 
> > +		rte_kvargs_free(kvlist);

> > +	return ret;

> >   }

> >

> >   static struct rte_driver pmd_af_packet_drv = {

> >

> 

> 

> --

> Pawel
  
Wodkowski, PawelX March 10, 2015, 8:59 a.m. UTC | #3
On 2015-03-10 09:49, Ouyang, Changchun wrote:
>
>
>> -----Original Message-----
>> From: Wodkowski, PawelX
>> Sent: Tuesday, March 10, 2015 4:37 PM
>> To: Ouyang, Changchun; dev@dpdk.org
>> Cc: linville@tuxdriver.com; nhorman@tuxdriver.com
>> Subject: Re: [PATCH v6] af_packet: Fix some klocwork errors
>>
>>> -
>>> -	return 0;
>>> +exit:
>>> +	if (kvlist != NULL)
>>
>> No need for if(). This part was fine previous patch.
>>
>
> If kvlist is NULL, no reason to call rte_kvargs_free to free it.
> So, adding this test is better.

For programmer convenience and reduce code bloat/obfuscation the same 
test is in rte_kvargs_free() (and every other free-like function). If 
there is no particular reason for that (ex performance which is not in 
this path) checking pointer for NULL value should be avoided before 
freeing it.

>
>>> +		rte_kvargs_free(kvlist);
>>> +	return ret;
>>>    }
>>>
>>>    static struct rte_driver pmd_af_packet_drv = {
>>>
>>
>>
>> --
>> Pawel
  
Thomas Monjalon March 10, 2015, 10:19 a.m. UTC | #4
2015-03-10 08:49, Ouyang, Changchun:
> From: Wodkowski, PawelX
> > > +	if (kvlist != NULL)
> > 
> > No need for if(). This part was fine previous patch.
> >
> 
> If kvlist is NULL, no reason to call rte_kvargs_free to free it.
> So, adding this test is better.

No, we don't need to double check.
1/ it's already checked in rte_kvargs_free()
2/ less lines you write, better it is

> > > +		rte_kvargs_free(kvlist);
> > > +	return ret;
> > >   }
  
Ouyang Changchun March 11, 2015, 1:18 a.m. UTC | #5
> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> Sent: Tuesday, March 10, 2015 6:20 PM
> To: Ouyang, Changchun
> Cc: dev@dpdk.org; Wodkowski, PawelX
> Subject: Re: [dpdk-dev] [PATCH v6] af_packet: Fix some klocwork errors
> 
> 2015-03-10 08:49, Ouyang, Changchun:
> > From: Wodkowski, PawelX
> > > > +	if (kvlist != NULL)
> > >
> > > No need for if(). This part was fine previous patch.
> > >
> >
> > If kvlist is NULL, no reason to call rte_kvargs_free to free it.
> > So, adding this test is better.
> 
> No, we don't need to double check.
> 1/ it's already checked in rte_kvargs_free() 2/ less lines you write, better it is
> 

At least 2 guys vote for removing the check, then 2 vs. 1, you win :-)
Will update it in v7

Thanks for comments!
Changchun
  

Patch

diff --git a/lib/librte_pmd_af_packet/rte_eth_af_packet.c b/lib/librte_pmd_af_packet/rte_eth_af_packet.c
index 80e9bdf..c2c0878 100644
--- a/lib/librte_pmd_af_packet/rte_eth_af_packet.c
+++ b/lib/librte_pmd_af_packet/rte_eth_af_packet.c
@@ -442,7 +442,8 @@  rte_pmd_init_internals(const char *name,
 	struct tpacket_req *req;
 	struct pkt_rx_queue *rx_queue;
 	struct pkt_tx_queue *tx_queue;
-	int rc, qsockfd, tpver, discard;
+	int rc, tpver, discard;
+	int qsockfd = -1;
 	unsigned int i, q, rdsize;
 	int fanout_arg __rte_unused, bypass __rte_unused;
 
@@ -691,9 +692,14 @@  error:
 				rte_free((*internals)->rx_queue[q].rd);
 			if ((*internals)->tx_queue[q].rd)
 				rte_free((*internals)->tx_queue[q].rd);
+			if (((*internals)->rx_queue[q].sockfd != 0) &&
+				((*internals)->rx_queue[q].sockfd != qsockfd))
+				close((*internals)->rx_queue[q].sockfd);
 		}
 		rte_free(*internals);
 	}
+	if (qsockfd != -1)
+		close(qsockfd);
 	return -1;
 }
 
@@ -802,7 +808,7 @@  int
 rte_pmd_af_packet_devinit(const char *name, const char *params)
 {
 	unsigned numa_node;
-	int ret;
+	int ret = 0;
 	struct rte_kvargs *kvlist;
 	int sockfd = -1;
 
@@ -811,8 +817,10 @@  rte_pmd_af_packet_devinit(const char *name, const char *params)
 	numa_node = rte_socket_id();
 
 	kvlist = rte_kvargs_parse(params, valid_arguments);
-	if (kvlist == NULL)
-		return -1;
+	if (kvlist == NULL) {
+		ret = -1;
+		goto exit;
+	}
 
 	/*
 	 * If iface argument is passed we open the NICs and use them for
@@ -823,16 +831,16 @@  rte_pmd_af_packet_devinit(const char *name, const char *params)
 		ret = rte_kvargs_process(kvlist, ETH_AF_PACKET_IFACE_ARG,
 		                         &open_packet_iface, &sockfd);
 		if (ret < 0)
-			return -1;
+			goto exit;
 	}
 
 	ret = rte_eth_from_packet(name, &sockfd, numa_node, kvlist);
 	close(sockfd); /* no longer needed */
 
-	if (ret < 0)
-		return -1;
-
-	return 0;
+exit:
+	if (kvlist != NULL)
+		rte_kvargs_free(kvlist);
+	return ret;
 }
 
 static struct rte_driver pmd_af_packet_drv = {