xmalloc: Add and use xcalloc

Add a wrapper for calloc which checks for integer overflows in the
calculation of the size to allocate.

Use xcalloc to allocate an array of objects instead of calculating the
size ourselves, which might cause an integer overflow.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

1 files changed, 2 insertions, 2 deletions

diff --git a/ifpps.c b/ifpps.c
index 4cdcbf4..77c63a6 100644
--- a/ifpps.c
+++ b/ifpps.c
@@ -173,7 +173,7 @@ static inline int padding_from_num(int n)
 }
 
 #define STATS_ALLOC1(member)	\
-	do { stats->member = xzmalloc(cpus * sizeof(*(stats->member))); } while (0)
+	do { stats->member = xcalloc(cpus, sizeof(*(stats->member))); } while (0)
 
 static void stats_alloc(struct ifstat *stats, unsigned int cpus)
 {
@@ -1425,7 +1425,7 @@ int main(int argc, char **argv)
 	stats_alloc(&stats_new, cpus);
 	stats_alloc(&stats_delta, cpus);
 
-	cpu_hits = xzmalloc(cpus * sizeof(*cpu_hits));
+	cpu_hits = xcalloc(cpus, sizeof(*cpu_hits));
 
 	if (promisc)
 		ifflags = device_enter_promiscuous_mode(ifname);