[PATCH 0/2] Some fixes for overlayfs remove privs

From: Amir Goldstein <amir73il@gmail.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: Christian Brauner <brauner@kernel.org>,
	Yang Xu <xuyang2018.jy@fujitsu.com>,
	"Darrick J . Wong" <djwong@kernel.org>,
	Filipe Manana <fdmanana@kernel.org>,
	linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH 0/2] Some fixes for overlayfs remove privs
Date: Mon,  3 Oct 2022 15:30:38 +0300	[thread overview]
Message-ID: <20221003123040.900827-1-amir73il@gmail.com> (raw)

Miklos,

While running latest fstests on overlayfs-next, I noticed these
failures:
generic/673 generic/683 generic/684 generic/685 generic/686 generic/687

Christian has also reported those failures earlier.

Those are not regressions, those are 5 new tests added to fstests and
one test whose expected result was modified by fstests commit b3a59bb6
("generic/673: fix golden output to reflect vfs setgid behavior").

The following two patches aim to fix those test failures, but they are
incomplete - without those patches, the tests fail miserably in all test
cases, because no privs are stripped.

With those two patches, only two test cases are failing, which are the
two test cases whose expectation was changed by fstests commit b3a59bb6.
The reason was explained in [1] and the issue was fixed for xfs by kernel
commit e014f37db1a2 ("xfs: use setattr_copy to set vfs inode attributes").

Trying to figure out how to fix this hurts my brain, so I'll need
suggestions how to proceed.

Thanks,
Amir.

[1] https://lore.kernel.org/linux-xfs/CAL3q7H47iNQ=Wmk83WcGB-KBJVOEtR9+qGczzCeXJ9Y2KCV25Q@mail.gmail.com/

Amir Goldstein (2):
  ovl: remove privs in ovl_copyfile()
  ovl: remove privs in ovl_fallocate()

 fs/overlayfs/file.c | 28 +++++++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

-- 
2.25.1