Re: [PATCH v1] metrics: fix potential missing NULL termination
From: Bruce Richardson <hidden>
Date: 2018-02-20 15:11:17
On Tue, Feb 20, 2018 at 02:50:01PM +0000, Remy Horton wrote:
quoted hunk ↗ jump to hunk
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. Coverity issue: 143434 Fixes: 349950ddb9c5 ("metrics: add information metrics library") Signed-off-by: Remy Horton <redacted> --- lib/librte_metrics/rte_metrics.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)diff --git a/lib/librte_metrics/rte_metrics.c b/lib/librte_metrics/rte_metrics.c index 556ae1b..958ef3d 100644 --- a/lib/librte_metrics/rte_metrics.c +++ b/lib/librte_metrics/rte_metrics.c@@ -214,10 +214,15 @@ 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++) { strncpy(names[idx_name].name, stats->metadata[idx_name].name, RTE_METRICS_MAX_NAME_LEN); + /* Enforce NULL-termination. The source string should already + * be NULL-terminated, so this is to quieten lint checks.. + */ + names[idx_name].name[RTE_METRICS_MAX_NAME_LEN - 1] = '\0'; + } }
Again, I think the better fix is to replace strncpy with snprintf which will guarantee the null termination, unlike strncpy which is nasty that way. /Bruce