On 10/21/24 1:09 AM, Tyler Hicks wrote:
> On 2024-10-07 10:27:43, Eric Sandeen wrote:
>> Convert ecryptfs to the new mount API.
>>
>> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
>> ---
>> fs/ecryptfs/ecryptfs_kernel.h | 7 -
>> fs/ecryptfs/main.c | 393 +++++++++++++++++-----------------
>> 2 files changed, 198 insertions(+), 202 deletions(-)
>>
...
>> diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
>> index d03f1c6ccc1c..a7829983304e 100644
>> --- a/fs/ecryptfs/main.c
>> +++ b/fs/ecryptfs/main.c
...
>> +enum { Opt_sig, Opt_ecryptfs_sig,
>> + Opt_cipher, Opt_ecryptfs_cipher,
>> + Opt_ecryptfs_key_bytes,
>> + Opt_passthrough, Opt_xattr_metadata,
>> + Opt_encrypted_view, Opt_fnek_sig,
>> + Opt_fn_cipher, Opt_fn_cipher_key_bytes,
>> + Opt_unlink_sigs, Opt_mount_auth_tok_only,
>> + Opt_check_dev_ruid };
>
> checkpatch complains about these lines starting with spaces rather than
> a tab. I think that's a valid nit. Can we switch to tabs?
Oh, sure. They have spaces upstream and I didn't catch that when I tweaked
the enum.
>> - case ecryptfs_opt_err:
>> - default:
>> - printk(KERN_WARNING
>> - "%s: eCryptfs: unrecognized option [%s]\n",
>> - __func__, p);
>
> I think we lost this error message, which can be helpful for users when
> debugging mount(2) failures.
Invalid options never make it to the parsing function under the new mount
API, see below. Honestly we should be able to even remove default: but it seems
like most prior conversions don't do that, maybe to keep static checkers happy,
not sure.
> See below in your new code where we handle the default case for what I
> think we should include.
>
>> +
>> + opt = fs_parse(fc, ecryptfs_fs_param_spec, param, &result);
>> + if (opt < 0)
>> + return opt;
>> +
>> + switch (opt) {
>> + case Opt_sig:
>> + case Opt_ecryptfs_sig:
>> + rc = ecryptfs_add_global_auth_tok(mount_crypt_stat,
>> + param->string, 0);
>> + if (rc) {
>> + printk(KERN_ERR "Error attempting to register "
>> + "global sig; rc = [%d]\n", rc);
>
> Are we expected to be using errorf() and friends here rather than
> printk()?
That's kind of a debate. If you'd rather get rid of the kernel message and
send it out through the mount api message channel instead, I can make that
change. But if userspace doesn't capture the message from errorf, that change
would lose the message altogether.
I kind of feel like once userspace is really making use of the message channel,
we could go back and selectively change printks to the message channel where it
makes sense.
>> + return rc;;
>
> There's an extra semicolon here.
Ugh, sorry.
>> }
>> + ctx->sig_set = 1;
>> + break;
>> + case Opt_cipher:
>> + case Opt_ecryptfs_cipher:
>> + strscpy(mount_crypt_stat->global_default_cipher_name,
>> + param->string);
>> + ctx->cipher_name_set = 1;
>> + break;
>> + case Opt_ecryptfs_key_bytes:
>> + mount_crypt_stat->global_default_cipher_key_size =
>> + result.uint_32;
>> + ctx->cipher_key_bytes_set = 1;
>> + break;
>> + case Opt_passthrough:
>> + mount_crypt_stat->flags |=
>> + ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
>> + break;
>> + case Opt_xattr_metadata:
>> + mount_crypt_stat->flags |= ECRYPTFS_XATTR_METADATA_ENABLED;
>> + break;
>> + case Opt_encrypted_view:
>> + mount_crypt_stat->flags |= ECRYPTFS_XATTR_METADATA_ENABLED;
>> + mount_crypt_stat->flags |= ECRYPTFS_ENCRYPTED_VIEW_ENABLED;
>> + break;
>> + case Opt_fnek_sig:
>> + strscpy(mount_crypt_stat->global_default_fnek_sig,
>> + param->string);
>> + rc = ecryptfs_add_global_auth_tok(
>> + mount_crypt_stat,
>> + mount_crypt_stat->global_default_fnek_sig,
>> + ECRYPTFS_AUTH_TOK_FNEK);
>> + if (rc) {
>> + printk(KERN_ERR "Error attempting to register "
>> + "global fnek sig [%s]; rc = [%d]\n",
>> + mount_crypt_stat->global_default_fnek_sig, rc);
>
> Same errorf() question here.
Same answer. :) If you don't mind those messages disappearing from kernel logs
I can change it.
>> + return rc;
>> + }
>> + mount_crypt_stat->flags |=
>> + (ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES
>> + | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK);
>> + break;
>> + case Opt_fn_cipher:
>> + strscpy(mount_crypt_stat->global_default_fn_cipher_name,
>> + param->string);
>> + ctx->fn_cipher_name_set = 1;
>> + break;
>> + case Opt_fn_cipher_key_bytes:
>> + mount_crypt_stat->global_default_fn_cipher_key_bytes =
>> + result.uint_32;
>> + ctx->fn_cipher_key_bytes_set = 1;
>> + break;
>> + case Opt_unlink_sigs:
>> + mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
>> + break;
>> + case Opt_mount_auth_tok_only:
>> + mount_crypt_stat->flags |= ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY;
>> + break;
>> + case Opt_check_dev_ruid:
>> + ctx->check_ruid = 1;
>> + break;
>> + default:
>
> To retain the unrecognized option warning, I think we need this:
>
>
> printk(KERN_WARNING "%s: eCryptfs: unrecognized option [%s]\n",
> __func__, param->key);
I think you'll see that if you make that change, you never hit the default:
case and it's still not printed.
vfs_parse_fs_param() does do "invalf(fc, "%s: Unknown parameter '%s'", ..."
which sends the message back out over the api message interface, and modern util-linux
mount will emit it on the console.
For example (just since I had jfs handy and it's mount is simple) if I add:
default:
printk("default yo\n");
return -EINVAL;
and try it:
# mount -o loop,blahblah jfsfile mnt
mount: /root/jfs-test/mnt: fsconfig system call failed: jfs: Unknown parameter 'blahblah'.
dmesg(1) may have more information after failed mount system call.
# dmesg | tail -n 2
[61556.764697] JFS: nTxBlock = 8192, nTxLock = 65536
[61561.280700] loop1: detected capacity change from 0 to 204800
#
Thanks for the review, and sorry for the missed nitpicks.
-Eric
> Tyler
