diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c
index f3e9be4aa3..d10a482cad 100644
--- a/libavcodec/aacdec.c
+++ b/libavcodec/aacdec.c
@@ -2003,7 +2003,7 @@ static void apply_tns(float coef[1024], TemporalNoiseShaping *tns,
     int w, filt, m, i;
     int bottom, top, order, start, end, size, inc;
     float lpc[TNS_MAX_ORDER];
-    float tmp[TNS_MAX_ORDER];
+    float tmp[TNS_MAX_ORDER + 1];
 
     for (w = 0; w < ics->num_windows; w++) {
         bottom = ics->num_swb;