[dpdk-dev] [PATCH 0/2] Gcc-8 build fixes

[dpdk-dev] [PATCH 0/2] Gcc-8 build fixes

[Stephen Hemminger]

A couple of trivial patches since GCC-8 finds more string overflows
than earlier versions.

Stephen Hemminger (2):
  rte_mempool: fix strncpy warnings
  rte_metrics: fix strncpy truncation warning

 lib/librte_mbuf/rte_mbuf_pool_ops.c | 4 ++--
 lib/librte_metrics/rte_metrics.c    | 7 +++++--
 2 files changed, 7 insertions(+), 4 deletions(-)

-- 
2.16.2

[dpdk-dev] [PATCH 1/2] rte_mempool: fix strncpy warnings

[Stephen Hemminger]

Gcc-8 discovers issue with platform_mempool_ops.
rte_mbuf_pool_ops.c:26:3: error: ‘strncpy’ output truncated before
  terminating nul copying as many bytes from a string as its length
  [-Werror=stringop-truncation]
  strncpy(mz->addr, ops_name,  strlen(ops_name));

The issue is that the size should be size in destination not source.

Fixes: a3acc3144a76 ("mbuf: add pool ops selection functions")
---
 lib/librte_mbuf/rte_mbuf_pool_ops.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/librte_mbuf/rte_mbuf_pool_ops.c b/lib/librte_mbuf/rte_mbuf_pool_ops.c
index 48cc342002a5..661cf4fb401f 100644
--- a/lib/librte_mbuf/rte_mbuf_pool_ops.c
+++ b/lib/librte_mbuf/rte_mbuf_pool_ops.c
@@ -23,7 +23,7 @@ rte_mbuf_set_platform_mempool_ops(const char *ops_name)
 			RTE_MEMPOOL_OPS_NAMESIZE, SOCKET_ID_ANY, 0);
 		if (mz == NULL)
 			return -rte_errno;
-		strncpy(mz->addr, ops_name, strlen(ops_name));
+		strncpy(mz->addr, ops_name, sizeof(mz->addr) - 1);
 		return 0;
 	} else if (strcmp(mz->addr, ops_name) == 0) {
 		return 0;
@@ -62,7 +62,7 @@ rte_mbuf_set_user_mempool_ops(const char *ops_name)
 			return -rte_errno;
 	}
 
-	strncpy(mz->addr, ops_name, strlen(ops_name));
+	strncpy(mz->addr, ops_name, sizeof(mz->addr) - 1);
 	return 0;
 
 }
-- 
2.16.2

[dpdk-dev] [PATCH 2/2] rte_metrics: fix strncpy truncation warning

[Stephen Hemminger]

Fixes:
librte_metrics/rte_metrics.c:218:4: error: ‘strncpy’ specified
 bound 64 equals destination size [-Werror=stringop-truncation]
    strncpy(names[idx_name].name,
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     stats->metadata[idx_name].name,
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     RTE_METRICS_MAX_NAME_LEN);
     ~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/librte_metrics/rte_metrics.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/librte_metrics/rte_metrics.c b/lib/librte_metrics/rte_metrics.c
index 556ae1ba8b4d..ae79d4ab276e 100644
--- a/lib/librte_metrics/rte_metrics.c
+++ b/lib/librte_metrics/rte_metrics.c
@@ -214,10 +214,13 @@ rte_metrics_get_names(struct rte_metric_name *names,
 			rte_spinlock_unlock(&stats->lock);
 			return return_value;
 		}
-		for (idx_name = 0; idx_name < stats->cnt_stats; idx_name++)
+
+		for (idx_name = 0; idx_name < stats->cnt_stats; idx_name++) {
+			memset(names[idx_name].name, 0, RTE_METRICS_MAX_NAME_LEN);
 			strncpy(names[idx_name].name,
 				stats->metadata[idx_name].name,
-				RTE_METRICS_MAX_NAME_LEN);
+				RTE_METRICS_MAX_NAME_LEN - 1);
+		}
 	}
 	return_value = stats->cnt_stats;
 	rte_spinlock_unlock(&stats->lock);
-- 
2.16.2

Re: [dpdk-dev] [PATCH 1/2] rte_mempool: fix strncpy warnings

[Olivier Matz]

Hi Stephen,

On Mon, Mar 19, 2018 at 10:52:12AM -0700, Stephen Hemminger wrote:
> [dpdk-dev] [PATCH 1/2] rte_mempool: fix strncpy warnings

The title should be prefixed by "mbuf:" instead of "rte_mempool:"

> Gcc-8 discovers issue with platform_mempool_ops.
> rte_mbuf_pool_ops.c:26:3: error: ‘strncpy’ output truncated before
>   terminating nul copying as many bytes from a string as its length
>   [-Werror=stringop-truncation]
>   strncpy(mz->addr, ops_name,  strlen(ops_name));
> 
> The issue is that the size should be size in destination not source.
> 
> Fixes: a3acc3144a76 ("mbuf: add pool ops selection functions")
> ---
>  lib/librte_mbuf/rte_mbuf_pool_ops.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_mbuf/rte_mbuf_pool_ops.c b/lib/librte_mbuf/rte_mbuf_pool_ops.c
> index 48cc342002a5..661cf4fb401f 100644
> --- a/lib/librte_mbuf/rte_mbuf_pool_ops.c
> +++ b/lib/librte_mbuf/rte_mbuf_pool_ops.c
> @@ -23,7 +23,7 @@ rte_mbuf_set_platform_mempool_ops(const char *ops_name)
>  			RTE_MEMPOOL_OPS_NAMESIZE, SOCKET_ID_ANY, 0);
>  		if (mz == NULL)
>  			return -rte_errno;
> -		strncpy(mz->addr, ops_name, strlen(ops_name));
> +		strncpy(mz->addr, ops_name, sizeof(mz->addr) - 1);

sizeof(mz->addr) is the size of the pointer, which is probably not
what you want. It should be RTE_MEMPOOL_OPS_NAMESIZE.


>  		return 0;
>  	} else if (strcmp(mz->addr, ops_name) == 0) {
>  		return 0;
> @@ -62,7 +62,7 @@ rte_mbuf_set_user_mempool_ops(const char *ops_name)
>  			return -rte_errno;
>  	}
>  
> -	strncpy(mz->addr, ops_name, strlen(ops_name));
> +	strncpy(mz->addr, ops_name, sizeof(mz->addr) - 1);
>  	return 0;

Same here.


Olivier