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3 commits

Author SHA1 Message Date
Eric Biggers
00ec418110 quota: explicitly forbid quota files from being encrypted
commit d3cc1b0be258191d6360c82ea158c2972f8d3991 upstream.

Since commit d7e7b9af104c ("fscrypt: stop using keyrings subsystem for
fscrypt_master_key"), xfstest generic/270 causes a WARNING when run on
f2fs with test_dummy_encryption in the mount options:

$ kvm-xfstests -c f2fs/encrypt generic/270
[...]
WARNING: CPU: 1 PID: 2453 at fs/crypto/keyring.c:240 fscrypt_destroy_keyring+0x1f5/0x260

The cause of the WARNING is that not all encrypted inodes have been
evicted before fscrypt_destroy_keyring() is called, which violates an
assumption.  This happens because the test uses an external quota file,
which gets automatically encrypted due to test_dummy_encryption.

Encryption of quota files has never really been supported.  On ext4,
ext4_quota_read() does not decrypt the data, so encrypted quota files
are always considered invalid on ext4.  On f2fs, f2fs_quota_read() uses
the pagecache, so trying to use an encrypted quota file gets farther,
resulting in the issue described above being possible.  But this was
never intended to be possible, and there is no use case for it.

Therefore, make the quota support layer explicitly reject using
IS_ENCRYPTED inodes when quotaon is attempted.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Message-Id: <20230905003227.326998-1-ebiggers@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 11:43:25 +01:00
Jan Kara
a297c70541 quota: Fix slow quotaoff
commit 869b6ea1609f655a43251bf41757aa44e5350a8f upstream.

Eric has reported that commit dabc8b207566 ("quota: fix dqput() to
follow the guarantees dquot_srcu should provide") heavily increases
runtime of generic/270 xfstest for ext4 in nojournal mode. The reason
for this is that ext4 in nojournal mode leaves dquots dirty until the last
dqput() and thus the cleanup done in quota_release_workfn() has to write
them all. Due to the way quota_release_workfn() is written this results
in synchronize_srcu() call for each dirty dquot which makes the dquot
cleanup when turning quotas off extremely slow.

To be able to avoid synchronize_srcu() for each dirty dquot we need to
rework how we track dquots to be cleaned up. Instead of keeping the last
dquot reference while it is on releasing_dquots list, we drop it right
away and mark the dquot with new DQ_RELEASING_B bit instead. This way we
can we can remove dquot from releasing_dquots list when new reference to
it is acquired and thus there's no need to call synchronize_srcu() each
time we drop dq_list_lock.

References: https://lore.kernel.org/all/ZRytn6CxFK2oECUt@debian-BULLSEYE-live-builder-AMD64
Reported-by: Eric Whitney <enwlinux@gmail.com>
Fixes: dabc8b207566 ("quota: fix dqput() to follow the guarantees dquot_srcu should provide")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-08 11:25:43 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00