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From:   Daniil Lunev <dlunev@chromium.org>
To:     linux-fsdevel@vger.kernel.org
Cc:     fuse-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org,
        Daniil Lunev <dlunev@chromium.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Miklos Szeredi <miklos@szeredi.hu>
Subject: [PATCH 0/2] Prevent re-use of FUSE superblock after force unmount
Date:   Wed, 11 May 2022 11:30:55 +1000
Message-Id: <20220511013057.245827-1-dlunev@chromium.org>
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Force unmount of fuse severes the connection between FUSE driver and its
userspace counterpart. However, open file handles will prevent the
superblock from being reclaimed. An attempt to remount the filesystem at
the same endpoint will try re-using the superblock, if still present.
Since the superblock re-use path doesn't go through the fs-specific
superblock setup code, its state in FUSE case is already disfunctional,
and that will prevent the mount from succeeding.
The patchset adds a possibility to mark the superblock  "defunc", which
will prevent its re-use by the subsequent mounts, and uses the
functionality in FUSE driver.


Daniil Lunev (2):
  fs/super: Add a flag to mark super block defunc
  FUSE: Mark super block defunc on force unmount

 fs/fuse/inode.c    | 11 +++++++++--
 fs/super.c         |  4 ++--
 include/linux/fs.h |  1 +
 3 files changed, 12 insertions(+), 4 deletions(-)

-- 
2.31.0