From 4a6f70c03182b421d326831532edca32bcdb3fb1 Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Tue, 20 Feb 2024 15:11:26 +0000 Subject: Don't print excessively long ASN1 items in fuzzer Prevent spurious fuzzer timeouts by not printing ASN1 which is excessively long. This fixes a false positive encountered by OSS-Fuzz. Reviewed-by: Tomas Mraz Reviewed-by: Tom Cosgrove (Merged from https://github.com/openssl/openssl/pull/23640) --- fuzz/asn1.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/fuzz/asn1.c b/fuzz/asn1.c index ee602a08a3..d55554b7fd 100644 --- a/fuzz/asn1.c +++ b/fuzz/asn1.c @@ -312,10 +312,16 @@ int FuzzerTestOneInput(const uint8_t *buf, size_t len) ASN1_VALUE *o = ASN1_item_d2i(NULL, &b, len, i); if (o != NULL) { - BIO *bio = BIO_new(BIO_s_null()); - if (bio != NULL) { - ASN1_item_print(bio, o, 4, i, pctx); - BIO_free(bio); + /* + * Don't print excessively long output to prevent spurious fuzzer + * timeouts. + */ + if (b - buf < 10000) { + BIO *bio = BIO_new(BIO_s_null()); + if (bio != NULL) { + ASN1_item_print(bio, o, 4, i, pctx); + BIO_free(bio); + } } if (ASN1_item_i2d(o, &der, i) > 0) { OPENSSL_free(der); -- cgit v1.2.3