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Date:   Mon, 2 Oct 2023 03:52:56 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     linux-fsdevel@vger.kernel.org
Cc:     Christian Brauner <brauner@kernel.org>,
        Christoph Hellwig <hch@lst.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Namjae Jeon <linkinjeon@kernel.org>,
        David Sterba <dsterba@suse.com>,
        David Howells <dhowells@redhat.com>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Amir Goldstein <amir73il@gmail.com>,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Bob Peterson <rpeterso@redhat.com>,
        Steve French <sfrench@samba.org>,
        Luis Chamberlain <mcgrof@kernel.org>
Subject: Re: [RFC][PATCHES] fixes in methods exposed to rcu pathwalk
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 <20231002022846.GA3389589@ZenIV>
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PS: ceph ->d_revalidate() uses ->s_fs_info and stuff hanging off it
(mdsc) and I'm not familiar enough with the codebase to do anything
useful with it; AFAICS, there are UAF on fs shutdown, but I'd rather
leave that one to ceph folks.  NTFS3 ->d_hash() and ->d_compare()
do blocking allocations, and that stuff can be called under
rcu_read_lock(); ->d_compare() pretty much always is called so...