avcodec/aacpsy: Avoid floating point division by 0 of norm_fac

Fixes: Ticket7995 Fixes: CVE-2020-20446 Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
4 years ago · 223b5e8ac9
parent a7a7f32c8a
commit 223b5e8ac9
1 changed files with 1 additions and 1 deletions
--- a/libavcodec/aacpsy.c
+++ b/libavcodec/aacpsy.c
@ -794,7 +794,7 @@ static void psy_3gpp_analyze_channel(FFPsyContext *ctx, int channel,

        if (pe < 1.15f * desired_pe) {
            /* 6.6.1.3.6 "Final threshold modification by linearization" */
-            norm_fac = 1.0f / norm_fac;
+            norm_fac = norm_fac ? 1.0f / norm_fac : 0;
            for (w = 0; w < wi->num_windows*16; w += 16) {
                for (g = 0; g < num_bands; g++) {
                    AacPsyBand *band = &pch->band[w+g];