crypto: algapi - convert cra_refcnt to refcount_t

Reference counters should use refcount_t rather than atomic_t, since the
refcount_t implementation can prevent overflows, reducing the
exploitability of reference leak bugs.  crypto_alg.cra_refcount is a
reference counter with the usual semantics, so switch it over to
refcount_t.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers 2017-12-29 10:00:46 -06:00 committed by Herbert Xu
parent 809778e02c
commit ce8614a312
6 changed files with 11 additions and 11 deletions

View File

@ -62,7 +62,7 @@ static int crypto_check_alg(struct crypto_alg *alg)
if (alg->cra_priority < 0)
return -EINVAL;
atomic_set(&alg->cra_refcnt, 1);
refcount_set(&alg->cra_refcnt, 1);
return crypto_set_driver_name(alg);
}
@ -224,7 +224,7 @@ static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
if (!larval->adult)
goto free_larval;
atomic_set(&larval->alg.cra_refcnt, 1);
refcount_set(&larval->alg.cra_refcnt, 1);
memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
CRYPTO_MAX_ALG_NAME);
larval->alg.cra_priority = alg->cra_priority;
@ -399,7 +399,7 @@ int crypto_unregister_alg(struct crypto_alg *alg)
if (ret)
return ret;
BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
BUG_ON(refcount_read(&alg->cra_refcnt) != 1);
if (alg->cra_destroy)
alg->cra_destroy(alg);
@ -490,7 +490,7 @@ void crypto_unregister_template(struct crypto_template *tmpl)
up_write(&crypto_alg_sem);
hlist_for_each_entry_safe(inst, n, list, list) {
BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
crypto_free_instance(inst);
}
crypto_remove_final(&users);

View File

@ -137,7 +137,7 @@ static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
if (IS_ERR(larval))
return ERR_CAST(larval);
atomic_set(&larval->alg.cra_refcnt, 2);
refcount_set(&larval->alg.cra_refcnt, 2);
down_write(&crypto_alg_sem);
alg = __crypto_alg_lookup(name, type, mask);

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@ -169,7 +169,7 @@ static int crypto_report_one(struct crypto_alg *alg,
ualg->cru_type = 0;
ualg->cru_mask = 0;
ualg->cru_flags = alg->cra_flags;
ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);
ualg->cru_refcnt = refcount_read(&alg->cra_refcnt);
if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
goto nla_put_failure;
@ -387,7 +387,7 @@ static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
goto drop_alg;
err = -EBUSY;
if (atomic_read(&alg->cra_refcnt) > 2)
if (refcount_read(&alg->cra_refcnt) > 2)
goto drop_alg;
err = crypto_unregister_instance((struct crypto_instance *)alg);

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@ -105,13 +105,13 @@ int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
static inline struct crypto_alg *crypto_alg_get(struct crypto_alg *alg)
{
atomic_inc(&alg->cra_refcnt);
refcount_inc(&alg->cra_refcnt);
return alg;
}
static inline void crypto_alg_put(struct crypto_alg *alg)
{
if (atomic_dec_and_test(&alg->cra_refcnt) && alg->cra_destroy)
if (refcount_dec_and_test(&alg->cra_refcnt) && alg->cra_destroy)
alg->cra_destroy(alg);
}

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@ -46,7 +46,7 @@ static int c_show(struct seq_file *m, void *p)
seq_printf(m, "driver : %s\n", alg->cra_driver_name);
seq_printf(m, "module : %s\n", module_name(alg->cra_module));
seq_printf(m, "priority : %d\n", alg->cra_priority);
seq_printf(m, "refcnt : %d\n", atomic_read(&alg->cra_refcnt));
seq_printf(m, "refcnt : %u\n", refcount_read(&alg->cra_refcnt));
seq_printf(m, "selftest : %s\n",
(alg->cra_flags & CRYPTO_ALG_TESTED) ?
"passed" : "unknown");

View File

@ -447,7 +447,7 @@ struct crypto_alg {
unsigned int cra_alignmask;
int cra_priority;
atomic_t cra_refcnt;
refcount_t cra_refcnt;
char cra_name[CRYPTO_MAX_ALG_NAME];
char cra_driver_name[CRYPTO_MAX_ALG_NAME];