crypto: qat - Fix invalid synchronization between register/unregister sym algs

[ Upstream commit 7047312d383203f7b8447261f1a473cf54aedec3 ]

commit 6f043b50da8e03bdcc5703fd37ea45bc6892432f upstream.

The synchronization method used atomic was bogus.
Use a proper synchronization with mutex.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c
index 9e9619cd4a79b958dae8e6ceee84d0d267325322..5b35e5d2231d944e66f882c1653ef067a42c9d63 100644 (file)
--- a/drivers/crypto/qat/qat_common/qat_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_algs.c
@@ -73,7 +73,8 @@
                        ICP_QAT_HW_CIPHER_KEY_CONVERT, \
                        ICP_QAT_HW_CIPHER_DECRYPT)
 
-static atomic_t active_dev;
+static DEFINE_MUTEX(algs_lock);
+static unsigned int active_devs;
 
 struct qat_alg_buf {
        uint32_t len;
@@ -955,27 +956,34 @@ static struct crypto_alg qat_algs[] = { {
 
 int qat_algs_register(void)
 {
-       if (atomic_add_return(1, &active_dev) == 1) {
+       int ret = 0;
+
+       mutex_lock(&algs_lock);
+       if (++active_devs == 1) {
                int i;
 
                for (i = 0; i < ARRAY_SIZE(qat_algs); i++)
                        qat_algs[i].cra_flags = CRYPTO_ALG_TYPE_AEAD |
                                                CRYPTO_ALG_ASYNC;
-               return crypto_register_algs(qat_algs, ARRAY_SIZE(qat_algs));
+               ret = crypto_register_algs(qat_algs, ARRAY_SIZE(qat_algs));
        }
-       return 0;
+       mutex_unlock(&algs_lock);
+       return ret;
 }
 
 int qat_algs_unregister(void)
 {
-       if (atomic_sub_return(1, &active_dev) == 0)
-               return crypto_unregister_algs(qat_algs, ARRAY_SIZE(qat_algs));
-       return 0;
+       int ret = 0;
+
+       mutex_lock(&algs_lock);
+       if (--active_devs == 0)
+               ret = crypto_unregister_algs(qat_algs, ARRAY_SIZE(qat_algs));
+       mutex_unlock(&algs_lock);
+       return ret;
 }
 
 int qat_algs_init(void)
 {
-       atomic_set(&active_dev, 0);
        crypto_get_default_rng();
        return 0;
 }