crypto: cryptd - Use refcount_t for refcount

Reference counters are preferred to use refcount_t instead of
atomic_t.
This is because the implementation of refcount_t can prevent
overflows and detect possible use-after-free.
So convert atomic_t ref counters to refcount_t.

Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Chuhong Yuan 2019-08-08 16:00:22 +08:00 committed by Herbert Xu
parent 03a3bb7ae6
commit 43b970fa82

View File

@ -16,7 +16,7 @@
#include <crypto/internal/aead.h> #include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h> #include <crypto/internal/skcipher.h>
#include <crypto/cryptd.h> #include <crypto/cryptd.h>
#include <linux/atomic.h> #include <linux/refcount.h>
#include <linux/err.h> #include <linux/err.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/kernel.h> #include <linux/kernel.h>
@ -63,7 +63,7 @@ struct aead_instance_ctx {
}; };
struct cryptd_skcipher_ctx { struct cryptd_skcipher_ctx {
atomic_t refcnt; refcount_t refcnt;
struct crypto_sync_skcipher *child; struct crypto_sync_skcipher *child;
}; };
@ -72,7 +72,7 @@ struct cryptd_skcipher_request_ctx {
}; };
struct cryptd_hash_ctx { struct cryptd_hash_ctx {
atomic_t refcnt; refcount_t refcnt;
struct crypto_shash *child; struct crypto_shash *child;
}; };
@ -82,7 +82,7 @@ struct cryptd_hash_request_ctx {
}; };
struct cryptd_aead_ctx { struct cryptd_aead_ctx {
atomic_t refcnt; refcount_t refcnt;
struct crypto_aead *child; struct crypto_aead *child;
}; };
@ -127,7 +127,7 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
{ {
int cpu, err; int cpu, err;
struct cryptd_cpu_queue *cpu_queue; struct cryptd_cpu_queue *cpu_queue;
atomic_t *refcnt; refcount_t *refcnt;
cpu = get_cpu(); cpu = get_cpu();
cpu_queue = this_cpu_ptr(queue->cpu_queue); cpu_queue = this_cpu_ptr(queue->cpu_queue);
@ -140,10 +140,10 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
queue_work_on(cpu, cryptd_wq, &cpu_queue->work); queue_work_on(cpu, cryptd_wq, &cpu_queue->work);
if (!atomic_read(refcnt)) if (!refcount_read(refcnt))
goto out_put_cpu; goto out_put_cpu;
atomic_inc(refcnt); refcount_inc(refcnt);
out_put_cpu: out_put_cpu:
put_cpu(); put_cpu();
@ -270,13 +270,13 @@ static void cryptd_skcipher_complete(struct skcipher_request *req, int err)
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm); struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req); struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req);
int refcnt = atomic_read(&ctx->refcnt); int refcnt = refcount_read(&ctx->refcnt);
local_bh_disable(); local_bh_disable();
rctx->complete(&req->base, err); rctx->complete(&req->base, err);
local_bh_enable(); local_bh_enable();
if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt)) if (err != -EINPROGRESS && refcnt && refcount_dec_and_test(&ctx->refcnt))
crypto_free_skcipher(tfm); crypto_free_skcipher(tfm);
} }
@ -521,13 +521,13 @@ static void cryptd_hash_complete(struct ahash_request *req, int err)
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(tfm); struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(tfm);
struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req); struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
int refcnt = atomic_read(&ctx->refcnt); int refcnt = refcount_read(&ctx->refcnt);
local_bh_disable(); local_bh_disable();
rctx->complete(&req->base, err); rctx->complete(&req->base, err);
local_bh_enable(); local_bh_enable();
if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt)) if (err != -EINPROGRESS && refcnt && refcount_dec_and_test(&ctx->refcnt))
crypto_free_ahash(tfm); crypto_free_ahash(tfm);
} }
@ -772,13 +772,13 @@ static void cryptd_aead_crypt(struct aead_request *req,
out: out:
ctx = crypto_aead_ctx(tfm); ctx = crypto_aead_ctx(tfm);
refcnt = atomic_read(&ctx->refcnt); refcnt = refcount_read(&ctx->refcnt);
local_bh_disable(); local_bh_disable();
compl(&req->base, err); compl(&req->base, err);
local_bh_enable(); local_bh_enable();
if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt)) if (err != -EINPROGRESS && refcnt && refcount_dec_and_test(&ctx->refcnt))
crypto_free_aead(tfm); crypto_free_aead(tfm);
} }
@ -979,7 +979,7 @@ struct cryptd_skcipher *cryptd_alloc_skcipher(const char *alg_name,
} }
ctx = crypto_skcipher_ctx(tfm); ctx = crypto_skcipher_ctx(tfm);
atomic_set(&ctx->refcnt, 1); refcount_set(&ctx->refcnt, 1);
return container_of(tfm, struct cryptd_skcipher, base); return container_of(tfm, struct cryptd_skcipher, base);
} }
@ -997,7 +997,7 @@ bool cryptd_skcipher_queued(struct cryptd_skcipher *tfm)
{ {
struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base); struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base);
return atomic_read(&ctx->refcnt) - 1; return refcount_read(&ctx->refcnt) - 1;
} }
EXPORT_SYMBOL_GPL(cryptd_skcipher_queued); EXPORT_SYMBOL_GPL(cryptd_skcipher_queued);
@ -1005,7 +1005,7 @@ void cryptd_free_skcipher(struct cryptd_skcipher *tfm)
{ {
struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base); struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base);
if (atomic_dec_and_test(&ctx->refcnt)) if (refcount_dec_and_test(&ctx->refcnt))
crypto_free_skcipher(&tfm->base); crypto_free_skcipher(&tfm->base);
} }
EXPORT_SYMBOL_GPL(cryptd_free_skcipher); EXPORT_SYMBOL_GPL(cryptd_free_skcipher);
@ -1029,7 +1029,7 @@ struct cryptd_ahash *cryptd_alloc_ahash(const char *alg_name,
} }
ctx = crypto_ahash_ctx(tfm); ctx = crypto_ahash_ctx(tfm);
atomic_set(&ctx->refcnt, 1); refcount_set(&ctx->refcnt, 1);
return __cryptd_ahash_cast(tfm); return __cryptd_ahash_cast(tfm);
} }
@ -1054,7 +1054,7 @@ bool cryptd_ahash_queued(struct cryptd_ahash *tfm)
{ {
struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base); struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base);
return atomic_read(&ctx->refcnt) - 1; return refcount_read(&ctx->refcnt) - 1;
} }
EXPORT_SYMBOL_GPL(cryptd_ahash_queued); EXPORT_SYMBOL_GPL(cryptd_ahash_queued);
@ -1062,7 +1062,7 @@ void cryptd_free_ahash(struct cryptd_ahash *tfm)
{ {
struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base); struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base);
if (atomic_dec_and_test(&ctx->refcnt)) if (refcount_dec_and_test(&ctx->refcnt))
crypto_free_ahash(&tfm->base); crypto_free_ahash(&tfm->base);
} }
EXPORT_SYMBOL_GPL(cryptd_free_ahash); EXPORT_SYMBOL_GPL(cryptd_free_ahash);
@ -1086,7 +1086,7 @@ struct cryptd_aead *cryptd_alloc_aead(const char *alg_name,
} }
ctx = crypto_aead_ctx(tfm); ctx = crypto_aead_ctx(tfm);
atomic_set(&ctx->refcnt, 1); refcount_set(&ctx->refcnt, 1);
return __cryptd_aead_cast(tfm); return __cryptd_aead_cast(tfm);
} }
@ -1104,7 +1104,7 @@ bool cryptd_aead_queued(struct cryptd_aead *tfm)
{ {
struct cryptd_aead_ctx *ctx = crypto_aead_ctx(&tfm->base); struct cryptd_aead_ctx *ctx = crypto_aead_ctx(&tfm->base);
return atomic_read(&ctx->refcnt) - 1; return refcount_read(&ctx->refcnt) - 1;
} }
EXPORT_SYMBOL_GPL(cryptd_aead_queued); EXPORT_SYMBOL_GPL(cryptd_aead_queued);
@ -1112,7 +1112,7 @@ void cryptd_free_aead(struct cryptd_aead *tfm)
{ {
struct cryptd_aead_ctx *ctx = crypto_aead_ctx(&tfm->base); struct cryptd_aead_ctx *ctx = crypto_aead_ctx(&tfm->base);
if (atomic_dec_and_test(&ctx->refcnt)) if (refcount_dec_and_test(&ctx->refcnt))
crypto_free_aead(&tfm->base); crypto_free_aead(&tfm->base);
} }
EXPORT_SYMBOL_GPL(cryptd_free_aead); EXPORT_SYMBOL_GPL(cryptd_free_aead);