ext4 crypto: fail the mount if blocksize != pagesize

We currently don't correctly handle the case where blocksize !=
pagesize, so disallow the mount in those cases.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 9 insertions, 1 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 31e85bea9652..e13fe40d4a51 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4065,7 +4065,15 @@ no_journal:
                 }
         }
 
-        if (unlikely(sbi->s_mount_flags & EXT4_MF_TEST_DUMMY_ENCRYPTION) &&
+        if ((DUMMY_ENCRYPTION_ENABLED(sbi) ||
+             EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) &&
+            (blocksize != PAGE_CACHE_SIZE)) {
+                ext4_msg(sb, KERN_ERR,
+                         "Unsupported blocksize for fs encryption");
+                goto failed_mount_wq;
+        }
+
+        if (DUMMY_ENCRYPTION_ENABLED(sbi) &&
             !(sb->s_flags & MS_RDONLY) &&
             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) {
                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);