[PATCH net-next 2/2] Crypto/chcr: Checking cra_refcnt before unregistering the algorithms

[Ayush Sawal]

This patch puts a check for algorithm unregister, to avoid removal of
driver if the algorithm is under use.

Signed-off-by: Ayush Sawal <ayush.sa...@chelsio.com>
---
 drivers/crypto/chelsio/chcr_algo.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/chelsio/chcr_algo.c 
b/drivers/crypto/chelsio/chcr_algo.c
index f8b55137cf7d..4c2553672b6f 100644
--- a/drivers/crypto/chelsio/chcr_algo.c
+++ b/drivers/crypto/chelsio/chcr_algo.c
@@ -4391,22 +4391,32 @@ static int chcr_unregister_alg(void)
        for (i = 0; i < ARRAY_SIZE(driver_algs); i++) {
                switch (driver_algs[i].type & CRYPTO_ALG_TYPE_MASK) {
                case CRYPTO_ALG_TYPE_SKCIPHER:
-                       if (driver_algs[i].is_registered)
+                       if (driver_algs[i].is_registered && refcount_read(
+                           &driver_algs[i].alg.skcipher.base.cra_refcnt)
+                           == 1) {
                                crypto_unregister_skcipher(
                                                &driver_algs[i].alg.skcipher);
+                               driver_algs[i].is_registered = 0;
+                       }
                        break;
                case CRYPTO_ALG_TYPE_AEAD:
-                       if (driver_algs[i].is_registered)
+                       if (driver_algs[i].is_registered && refcount_read(
+                           &driver_algs[i].alg.aead.base.cra_refcnt) == 1) {
                                crypto_unregister_aead(
                                                &driver_algs[i].alg.aead);
+                               driver_algs[i].is_registered = 0;
+                       }
                        break;
                case CRYPTO_ALG_TYPE_AHASH:
-                       if (driver_algs[i].is_registered)
+                       if (driver_algs[i].is_registered && refcount_read(
+                           &driver_algs[i].alg.hash.halg.base.cra_refcnt)
+                           == 1) {
                                crypto_unregister_ahash(
                                                &driver_algs[i].alg.hash);
+                               driver_algs[i].is_registered = 0;
+                       }
                        break;
                }
-               driver_algs[i].is_registered = 0;
        }
        return 0;
 }
-- 
2.26.0.rc1.11.g30e9940