fs: Rename SB_I_EVM_UNSUPPORTED to SB_I_EVM_HMAC_UNSUPPORTED

Now that EVM supports RSA signatures for previously completely
unsupported filesystems rename the flag SB_I_EVM_UNSUPPORTED to
SB_I_EVM_HMAC_UNSUPPORTED to reflect that only HMAC is not supported.
Suggested-by: Amir Goldstein <amir73il@gmail.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

fs/overlayfs/super.c

@@ -1460,7 +1460,7 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc)
 	 * lead to unexpected results.
 	 */
 	sb->s_iflags |= SB_I_NOUMASK;
-	sb->s_iflags |= SB_I_EVM_UNSUPPORTED;
+	sb->s_iflags |= SB_I_EVM_HMAC_UNSUPPORTED;
 
 	err = -ENOMEM;
 	root_dentry = ovl_get_root(sb, ctx->upper.dentry, oe);

include/linux/fs.h

@@ -1177,7 +1177,7 @@ extern int send_sigurg(struct fown_struct *fown);
 #define SB_I_USERNS_VISIBLE		0x00000010 /* fstype already mounted */
 #define SB_I_IMA_UNVERIFIABLE_SIGNATURE	0x00000020
 #define SB_I_UNTRUSTED_MOUNTER		0x00000040
-#define SB_I_EVM_UNSUPPORTED		0x00000080
+#define SB_I_EVM_HMAC_UNSUPPORTED	0x00000080
 
 #define SB_I_SKIP_SYNC	0x00000100	/* Skip superblock at global sync */
 #define SB_I_PERSB_BDI	0x00000200	/* has a per-sb bdi */

security/integrity/evm/evm_main.c

@@ -155,7 +155,7 @@ static int is_unsupported_fs(struct dentry *dentry)
 {
 	struct inode *inode = d_backing_inode(dentry);
 
-	if (inode->i_sb->s_iflags & SB_I_EVM_UNSUPPORTED) {
+	if (inode->i_sb->s_iflags & SB_I_EVM_HMAC_UNSUPPORTED) {
 		pr_info_once("%s not supported\n", inode->i_sb->s_type->name);
 		return 1;
 	}