asn1/tasn_utl.c: fix logical error in and overhaul asn1_do_lock.

CRYPTO_atomic_add was assumed to return negative value on error, while
it returns 0.

Reviewed-by: Rich Salz <rsalz@openssl.org>
This commit is contained in:
Andy Polyakov 2018-07-31 14:59:14 +02:00
parent f52292be10
commit 680b9d45b0

View file

@ -58,8 +58,10 @@ int asn1_set_choice_selector(ASN1_VALUE **pval, int value,
int asn1_do_lock(ASN1_VALUE **pval, int op, const ASN1_ITEM *it)
{
const ASN1_AUX *aux;
int *lck, ret;
CRYPTO_REF_COUNT *lck;
CRYPTO_RWLOCK **lock;
int ret = -1;
if ((it->itype != ASN1_ITYPE_SEQUENCE)
&& (it->itype != ASN1_ITYPE_NDEF_SEQUENCE))
return 0;
@ -68,25 +70,34 @@ int asn1_do_lock(ASN1_VALUE **pval, int op, const ASN1_ITEM *it)
return 0;
lck = offset2ptr(*pval, aux->ref_offset);
lock = offset2ptr(*pval, aux->ref_lock);
if (op == 0) {
*lck = 1;
switch (op) {
case 0:
*lck = ret = 1;
*lock = CRYPTO_THREAD_lock_new();
if (*lock == NULL) {
ASN1err(ASN1_F_ASN1_DO_LOCK, ERR_R_MALLOC_FAILURE);
return -1;
}
return 1;
}
if (CRYPTO_atomic_add(lck, op, &ret, *lock) < 0)
break;
case 1:
if (!CRYPTO_UP_REF(lck, &ret, *lock))
return -1;
break;
case -1:
if (!CRYPTO_DOWN_REF(lck, &ret, *lock))
return -1; /* failed */
#ifdef REF_PRINT
fprintf(stderr, "%p:%4d:%s\n", it, *lck, it->sname);
fprintf(stderr, "%p:%4d:%s\n", it, ret, it->sname);
#endif
REF_ASSERT_ISNT(ret < 0);
if (ret == 0) {
CRYPTO_THREAD_lock_free(*lock);
*lock = NULL;
}
break;
}
return ret;
}