refperf: Avoid null pointer dereference when buf fails to allocate

Currently in the unlikely event that buf fails to be allocated it is dereferenced a few times. Use the errexit flag to determine if buf should be written to to avoid the null pointer dereferences. Addresses-Coverity: ("Dereference after null check") Fixes: f518f15 ("refperf: Dynamically allocate experiment-summary output buffer") Signed-off-by: Colin Ian King <[email protected]> Signed-off-by: Paul E. McKenney <[email protected]>
josf · Aug 25, 2020 · 58db578 · 58db578
1 parent 57f6020
commit 58db578
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c
@@ -546,9 +546,11 @@ static int main_func(void *arg)
 	// Print the average of all experiments
 	SCALEOUT("END OF TEST. Calculating average duration per loop (nanoseconds)...\n");
 
-	buf[0] = 0;
-	strcat(buf, "\n");
-	strcat(buf, "Runs\tTime(ns)\n");
+	if (!errexit) {
+		buf[0] = 0;
+		strcat(buf, "\n");
+		strcat(buf, "Runs\tTime(ns)\n");
+	}
 
 	for (exp = 0; exp < nruns; exp++) {
 		u64 avg;