demux_mkv: limit EBML size to 64 MiB for fuzzing

OSS-Fuzz is limited to 2GiB of process memory, so allocating 512 MiB is not working well and causing OOMs.
mpv-player · Dec 12, 2024 · 5897b66 · 5897b66
1 parent c14af4e
commit 5897b66
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/demux/ebml.c b/demux/ebml.c
@@ -604,7 +604,11 @@ int ebml_read_element(struct stream *s, struct ebml_parse_ctx *ctx,
         MP_MSG(ctx, msglevel, "EBML element with unknown length - unsupported\n");
         return -1;
     }
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
     if (length > (512 << 20)) {
+#else
+    if (length > (64 << 20)) {
+#endif
         MP_MSG(ctx, msglevel, "Element too big (%" PRIu64 " MiB) - skipping\n", length >> 20);
         return -1;
     }