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Date:   Tue, 8 Nov 2022 09:41:30 -0800
From:   Eric Biggers <ebiggers@kernel.org>
To:     Alexander Potapenko <glider@google.com>
Cc:     syzbot <syzbot+9767be679ef5016b6082@syzkaller.appspotmail.com>,
        adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        tytso@mit.edu
Subject: Re: [syzbot] KMSAN: uninit-value in pagecache_write
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On Tue, Nov 08, 2022 at 10:08:36AM +0100, 'Alexander Potapenko' via syzkaller-bugs wrote:
> > >
> > > Anyway, this patch doesn't hurt, I suppose.  Can please you send it out as a
> > > formal patch to linux-ext4?  It would be easy for people to miss this patch
> > > buried in this thread.  Also, can you please send a patch to linux-f2fs-devel
> > > for the same code in fs/f2fs/verity.c?
> >
> > Will do!
> 
> Shall I also initialize fsdata here:
> 
> $ git grep 'void \*fsdata;'
> fs/affs/file.c:         void *fsdata;
> fs/ext4/verity.c:               void *fsdata;
> fs/f2fs/verity.c:               void *fsdata;
> fs/hfs/extent.c:                void *fsdata;
> fs/hfsplus/extents.c:           void *fsdata;
> fs/ocfs2/mmap.c:        void *fsdata;

Yes, it looks like they all need this.  Except maybe ocfs2?  It's hard to tell.

- Eric