The number of audio channels can be configured in SDP, and can thus be set to arbitrary values by an attacker. This CL fixes an out-of-bounds memory access that could occur when the number of channels is set to a large number. Bug: chromium:1265806 Change-Id: Ic88ff6d85b978b8eb99bf03cc52457a4552e8c24 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/237808 Reviewed-by: Jakob Ivarsson <jakobi@webrtc.org> Commit-Queue: Ivo Creusen <ivoc@webrtc.org> Cr-Commit-Position: refs/heads/main@{#35354}