A couple corrections I'll include in the next version:
On Sat, Apr 30, 2022 at 10:08:55PM -0700, Eric Biggers wrote:
> + if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
> + if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
> + &ctx->dummy_enc_policy))
> + return 0;
> ext4_msg(NULL, KERN_WARNING,
> - "Can't set test_dummy_encryption on remount");
> + "Can't set or change test_dummy_encryption on remount");
> return -EINVAL;
> }
I think this needs to be 'fc->purpose == FS_CONTEXT_FOR_RECONFIGURE ||
fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)', since ext4 can parse
mount options from both s_mount_opts and the regular mount options.
> +static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
> + struct super_block *sb)
> +{
> + if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
> + return;
To handle remounts correctly, this needs to be
'!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy)'.
- Eric
