From a8fef8b0f531d3795d6470e4b9119bba20d18f3b Mon Sep 17 00:00:00 2001 From: tb Date: Wed, 15 Mar 2023 06:14:02 +0000 Subject: [PATCH] Streaming BIOs assume they can write to NULL BIOs At least SMIME_text() relies on this. Pushing an error on the stack trips PKCS7 regress in py-cryptography, so indicate nothing was written instead of throwing an error. Reported by Alex Gaynor a while back ok jsing --- lib/libcrypto/bio/bio_lib.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/lib/libcrypto/bio/bio_lib.c b/lib/libcrypto/bio/bio_lib.c index 31b1e7305d8..d14507884b9 100644 --- a/lib/libcrypto/bio/bio_lib.c +++ b/lib/libcrypto/bio/bio_lib.c @@ -1,4 +1,4 @@ -/* $OpenBSD: bio_lib.c,v 1.43 2022/12/16 13:41:55 schwarze Exp $ */ +/* $OpenBSD: bio_lib.c,v 1.44 2023/03/15 06:14:02 tb Exp $ */ /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * @@ -380,10 +380,9 @@ BIO_write(BIO *b, const void *in, int inl) size_t writebytes = 0; int ret; - if (b == NULL) { - BIOerror(ERR_R_PASSED_NULL_PARAMETER); - return (-1); - } + /* Not an error. Things like SMIME_text() assume that this succeeds. */ + if (b == NULL) + return (0); if (inl <= 0) return (0); -- 2.20.1