From 04cf39207f94abf89b3964c7710f22f829a1a78f Mon Sep 17 00:00:00 2001 From: Bernd Edlinger Date: Wed, 8 Mar 2017 18:53:36 +0100 Subject: [PATCH] Fix a crash or unbounded allocation in RSA_padding_add_PKCS1_PSS_mgf1 and RSA_verify_PKCS1_PSS_mgf1 with 512-bit RSA vs. sha-512. Reviewed-by: Andy Polyakov Reviewed-by: Rich Salz (Merged from https://github.com/openssl/openssl/pull/2881) (cherry picked from commit e653b6cd74f70c04b0b96b07df00680b427603af) --- crypto/rsa/rsa_pss.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/crypto/rsa/rsa_pss.c b/crypto/rsa/rsa_pss.c index 41bc0844e4..2c3fd73b09 100644 --- a/crypto/rsa/rsa_pss.c +++ b/crypto/rsa/rsa_pss.c @@ -122,7 +122,11 @@ int RSA_verify_PKCS1_PSS_mgf1(RSA *rsa, const unsigned char *mHash, EM++; emLen--; } - if (emLen < (hLen + sLen + 2)) { /* sLen can be small negative */ + if (emLen < hLen + 2) { + RSAerr(RSA_F_RSA_VERIFY_PKCS1_PSS_MGF1, RSA_R_DATA_TOO_LARGE); + goto err; + } + if (sLen > emLen - hLen - 2) { /* sLen can be small negative */ RSAerr(RSA_F_RSA_VERIFY_PKCS1_PSS_MGF1, RSA_R_DATA_TOO_LARGE); goto err; } @@ -222,9 +226,14 @@ int RSA_padding_add_PKCS1_PSS_mgf1(RSA *rsa, unsigned char *EM, *EM++ = 0; emLen--; } + if (emLen < hLen + 2) { + RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_PSS_MGF1, + RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); + goto err; + } if (sLen == -2) { sLen = emLen - hLen - 2; - } else if (emLen < (hLen + sLen + 2)) { + } else if (sLen > emLen - hLen - 2) { RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_PSS_MGF1, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); goto err; -- 2.25.1