security, crypto: LLVMLinux: Remove VLAIS from ima_crypto.c

Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using a char array using the SHASH_DESC_ON_STACK macro.

The new code can be compiled with both gcc and clang.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: tglx@linutronix.de

1 files changed, 19 insertions, 28 deletions

diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index d34e7dfc1118..78d66dae15f4 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -386,17 +386,14 @@ static int ima_calc_file_hash_tfm(struct file *file,
         loff_t i_size, offset = 0;
         char *rbuf;
         int rc, read = 0;
-        struct {
-                struct shash_desc shash;
-                char ctx[crypto_shash_descsize(tfm)];
-        } desc;
+        SHASH_DESC_ON_STACK(shash, tfm);
 
-        desc.shash.tfm = tfm;
-        desc.shash.flags = 0;
+        shash->tfm = tfm;
+        shash->flags = 0;
 
         hash->length = crypto_shash_digestsize(tfm);
 
-        rc = crypto_shash_init(&desc.shash);
+        rc = crypto_shash_init(shash);
         if (rc != 0)
                 return rc;
 
@@ -426,7 +423,7 @@ static int ima_calc_file_hash_tfm(struct file *file,
                         break;
                 offset += rbuf_len;
 
-                rc = crypto_shash_update(&desc.shash, rbuf, rbuf_len);
+                rc = crypto_shash_update(shash, rbuf, rbuf_len);
                 if (rc)
                         break;
         }
@@ -435,7 +432,7 @@ static int ima_calc_file_hash_tfm(struct file *file,
         kfree(rbuf);
 out:
         if (!rc)
-                rc = crypto_shash_final(&desc.shash, hash->digest);
+                rc = crypto_shash_final(shash, hash->digest);
         return rc;
 }
 
@@ -493,18 +490,15 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
                                          struct ima_digest_data *hash,
                                          struct crypto_shash *tfm)
 {
-        struct {
-                struct shash_desc shash;
-                char ctx[crypto_shash_descsize(tfm)];
-        } desc;
+        SHASH_DESC_ON_STACK(shash, tfm);
         int rc, i;
 
-        desc.shash.tfm = tfm;
-        desc.shash.flags = 0;
+        shash->tfm = tfm;
+        shash->flags = 0;
 
         hash->length = crypto_shash_digestsize(tfm);
 
-        rc = crypto_shash_init(&desc.shash);
+        rc = crypto_shash_init(shash);
         if (rc != 0)
                 return rc;
 
@@ -514,7 +508,7 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
                 u32 datalen = field_data[i].len;
 
                 if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) {
-                        rc = crypto_shash_update(&desc.shash,
+                        rc = crypto_shash_update(shash,
                                                 (const u8 *) &field_data[i].len,
                                                 sizeof(field_data[i].len));
                         if (rc)
@@ -524,13 +518,13 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
                         data_to_hash = buffer;
                         datalen = IMA_EVENT_NAME_LEN_MAX + 1;
                 }
-                rc = crypto_shash_update(&desc.shash, data_to_hash, datalen);
+                rc = crypto_shash_update(shash, data_to_hash, datalen);
                 if (rc)
                         break;
         }
 
         if (!rc)
-                rc = crypto_shash_final(&desc.shash, hash->digest);
+                rc = crypto_shash_final(shash, hash->digest);
 
         return rc;
 }
@@ -571,15 +565,12 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest,
 {
         u8 pcr_i[TPM_DIGEST_SIZE];
         int rc, i;
-        struct {
-                struct shash_desc shash;
-                char ctx[crypto_shash_descsize(tfm)];
-        } desc;
+        SHASH_DESC_ON_STACK(shash, tfm);
 
-        desc.shash.tfm = tfm;
-        desc.shash.flags = 0;
+        shash->tfm = tfm;
+        shash->flags = 0;
 
-        rc = crypto_shash_init(&desc.shash);
+        rc = crypto_shash_init(shash);
         if (rc != 0)
                 return rc;
 
@@ -587,10 +578,10 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest,
         for (i = TPM_PCR0; i < TPM_PCR8; i++) {
                 ima_pcrread(i, pcr_i);
                 /* now accumulate with current aggregate */
-                rc = crypto_shash_update(&desc.shash, pcr_i, TPM_DIGEST_SIZE);
+                rc = crypto_shash_update(shash, pcr_i, TPM_DIGEST_SIZE);
         }
         if (!rc)
-                crypto_shash_final(&desc.shash, digest);
+                crypto_shash_final(shash, digest);
         return rc;
 }