From 6495cab1c876ad80ce983d848ccaa1dc286a63e1 Mon Sep 17 00:00:00 2001 From: slontis Date: Fri, 1 Jul 2022 13:47:11 +1000 Subject: [PATCH] Fix bn_gcd code to check return value when calling BN_one() BN_one() uses the expand function which calls malloc which may fail. All other places that reference BN_one() check the return value. The issue is triggered by a memory allocation failure. Detected by PR #18355 Reviewed-by: Tomas Mraz Reviewed-by: Paul Dale (Merged from https://github.com/openssl/openssl/pull/18697) (cherry picked from commit 7fe7cc57af3db1e497877f0329ba17609b2efc8b) --- crypto/bn/bn_gcd.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/crypto/bn/bn_gcd.c b/crypto/bn/bn_gcd.c index 0941f7b97f3f7..c4b7854e1ab4b 100644 --- a/crypto/bn/bn_gcd.c +++ b/crypto/bn/bn_gcd.c @@ -47,7 +47,8 @@ BIGNUM *bn_mod_inverse_no_branch(BIGNUM *in, if (R == NULL) goto err; - BN_one(X); + if (!BN_one(X)) + goto err; BN_zero(Y); if (BN_copy(B, a) == NULL) goto err; @@ -235,7 +236,8 @@ BIGNUM *int_bn_mod_inverse(BIGNUM *in, if (R == NULL) goto err; - BN_one(X); + if (!BN_one(X)) + goto err; BN_zero(Y); if (BN_copy(B, a) == NULL) goto err;