diff options
author | Dr. Stephen Henson <steve@openssl.org> | 2015-11-10 19:03:07 +0000 |
---|---|---|
committer | Matt Caswell <matt@openssl.org> | 2015-12-03 14:32:05 +0000 |
commit | cc598f321fbac9c04da5766243ed55d55948637d (patch) | |
tree | bff3dba6e776736ce5576cb6dc6535601ad269db | |
parent | fb4f46763fed3c600db21974577061b611b6fa46 (diff) |
Fix leak with ASN.1 combine.
When parsing a combined structure pass a flag to the decode routine
so on error a pointer to the parent structure is not zeroed as
this will leak any additional components in the parent.
This can leak memory in any application parsing PKCS#7 or CMS structures.
CVE-2015-3195.
Thanks to Adam Langley (Google/BoringSSL) for discovering this bug using
libFuzzer.
PR#4131
Reviewed-by: Richard Levitte <levitte@openssl.org>
-rw-r--r-- | crypto/asn1/tasn_dec.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/crypto/asn1/tasn_dec.c b/crypto/asn1/tasn_dec.c index febf6059cb..9256049d15 100644 --- a/crypto/asn1/tasn_dec.c +++ b/crypto/asn1/tasn_dec.c @@ -180,6 +180,8 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, int otag; int ret = 0; ASN1_VALUE **pchptr, *ptmpval; + int combine = aclass & ASN1_TFLG_COMBINE; + aclass &= ~ASN1_TFLG_COMBINE; if (!pval) return 0; if (aux && aux->asn1_cb) @@ -500,7 +502,8 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, auxerr: ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR); err: - ASN1_item_ex_free(pval, it); + if (combine == 0) + ASN1_item_ex_free(pval, it); if (errtt) ERR_add_error_data(4, "Field=", errtt->field_name, ", Type=", it->sname); @@ -689,7 +692,7 @@ static int asn1_template_noexp_d2i(ASN1_VALUE **val, } else { /* Nothing special */ ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), - -1, 0, opt, ctx); + -1, tt->flags & ASN1_TFLG_COMBINE, opt, ctx); if (!ret) { ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; |