[dpdk-dev,v2] metrics: fix potential missing NULL termination
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Commit Message
Fixes a potential memory overrun detected by Coverity.
This overrun cannot currently happen in practice because
rte_metrics_reg_names() explicitly forces the last name
character to be a NULL terminator. This patch adds the
same enforcement to rte_metrics_get_names() in order to
correct the warning, as well as using snprintf instead
of strncpy to copy name strings.
Coverity issue: 143434
Fixes: 349950ddb9c5 ("metrics: add information metrics library")
Fixes: 710cab6f675a ("metrics: fix out of bound access")
Signed-off-by: Remy Horton <remy.horton@intel.com>
--
Changes in v2
* Replace strncpy with snprintf
---
lib/librte_metrics/rte_metrics.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
Comments
On 2/20/2018 4:05 PM, Remy Horton wrote:
> Fixes a potential memory overrun detected by Coverity.
> This overrun cannot currently happen in practice because
> rte_metrics_reg_names() explicitly forces the last name
> character to be a NULL terminator. This patch adds the
> same enforcement to rte_metrics_get_names() in order to
> correct the warning, as well as using snprintf instead
> of strncpy to copy name strings.
There is a patch from Bruce to convert snprintf to strlcpy [1], this patch can
be part of that one.
[1]
https://dpdk.org/dev/patchwork/patch/35976/
>
> Coverity issue: 143434
> Fixes: 349950ddb9c5 ("metrics: add information metrics library")
> Fixes: 710cab6f675a ("metrics: fix out of bound access")
>
> Signed-off-by: Remy Horton <remy.horton@intel.com>
<...>
22/03/2018 11:33, Ferruh Yigit:
> On 2/20/2018 4:05 PM, Remy Horton wrote:
> > Fixes a potential memory overrun detected by Coverity.
> > This overrun cannot currently happen in practice because
> > rte_metrics_reg_names() explicitly forces the last name
> > character to be a NULL terminator. This patch adds the
> > same enforcement to rte_metrics_get_names() in order to
> > correct the warning, as well as using snprintf instead
> > of strncpy to copy name strings.
>
> There is a patch from Bruce to convert snprintf to strlcpy [1], this patch can
> be part of that one.
>
> [1]
> https://dpdk.org/dev/patchwork/patch/35976/
>
> >
> > Coverity issue: 143434
> > Fixes: 349950ddb9c5 ("metrics: add information metrics library")
> > Fixes: 710cab6f675a ("metrics: fix out of bound access")
> >
> > Signed-off-by: Remy Horton <remy.horton@intel.com>
Updated to use strlcpy and applied.
@@ -113,10 +113,8 @@ rte_metrics_reg_names(const char * const *names, uint16_t cnt_names)
for (idx_name = 0; idx_name < cnt_names; idx_name++) {
entry = &stats->metadata[idx_name + stats->cnt_stats];
- strncpy(entry->name, names[idx_name],
- RTE_METRICS_MAX_NAME_LEN);
- /* Enforce NULL-termination */
- entry->name[RTE_METRICS_MAX_NAME_LEN - 1] = '\0';
+ snprintf(entry->name, RTE_METRICS_MAX_NAME_LEN,
+ "%s", names[idx_name]);
memset(entry->value, 0, sizeof(entry->value));
entry->idx_next_stat = idx_name + stats->cnt_stats + 1;
}
@@ -215,9 +213,9 @@ rte_metrics_get_names(struct rte_metric_name *names,
return return_value;
}
for (idx_name = 0; idx_name < stats->cnt_stats; idx_name++)
- strncpy(names[idx_name].name,
- stats->metadata[idx_name].name,
- RTE_METRICS_MAX_NAME_LEN);
+ snprintf(names[idx_name].name,
+ RTE_METRICS_MAX_NAME_LEN,
+ "%s", stats->metadata[idx_name].name);
}
return_value = stats->cnt_stats;
rte_spinlock_unlock(&stats->lock);