crypto: arm/aes-neonbs - fix usage of cbc(aes) fallback
authorHoria Geantă <horia.geanta@nxp.com>
Wed, 28 Oct 2020 09:03:20 +0000 (11:03 +0200)
committerHerbert Xu <herbert@gondor.apana.org.au>
Fri, 6 Nov 2020 03:31:15 +0000 (14:31 +1100)
Loading the module deadlocks since:
-local cbc(aes) implementation needs a fallback and
-crypto API tries to find one but the request_module() resolves back to
the same module

Fix this by changing the module alias for cbc(aes) and
using the NEED_FALLBACK flag when requesting for a fallback algorithm.

Fixes: 00b99ad2bac2 ("crypto: arm/aes-neonbs - Use generic cbc encryption path")
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
arch/arm/crypto/aes-neonbs-glue.c

index bda8bf1..f70af1d 100644 (file)
@@ -19,7 +19,7 @@ MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
 MODULE_LICENSE("GPL v2");
 
 MODULE_ALIAS_CRYPTO("ecb(aes)");
-MODULE_ALIAS_CRYPTO("cbc(aes)");
+MODULE_ALIAS_CRYPTO("cbc(aes)-all");
 MODULE_ALIAS_CRYPTO("ctr(aes)");
 MODULE_ALIAS_CRYPTO("xts(aes)");
 
@@ -191,7 +191,8 @@ static int cbc_init(struct crypto_skcipher *tfm)
        struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
        unsigned int reqsize;
 
-       ctx->enc_tfm = crypto_alloc_skcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC);
+       ctx->enc_tfm = crypto_alloc_skcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC |
+                                            CRYPTO_ALG_NEED_FALLBACK);
        if (IS_ERR(ctx->enc_tfm))
                return PTR_ERR(ctx->enc_tfm);
 
@@ -441,7 +442,8 @@ static struct skcipher_alg aes_algs[] = { {
        .base.cra_blocksize     = AES_BLOCK_SIZE,
        .base.cra_ctxsize       = sizeof(struct aesbs_cbc_ctx),
        .base.cra_module        = THIS_MODULE,
-       .base.cra_flags         = CRYPTO_ALG_INTERNAL,
+       .base.cra_flags         = CRYPTO_ALG_INTERNAL |
+                                 CRYPTO_ALG_NEED_FALLBACK,
 
        .min_keysize            = AES_MIN_KEY_SIZE,
        .max_keysize            = AES_MAX_KEY_SIZE,