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Date: Wed, 16 Oct 2024 15:16:36 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Jeongjun Park <aha310510@gmail.com>
Cc: hughd@google.com, yuzhao@google.com, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org, syzbot <syzkaller@googlegroups.com>,
 stable@vger.kernel.org
Subject: Re: [PATCH RESEND] mm: shmem: fix data-race in shmem_getattr()
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On Wed, 16 Oct 2024 23:12:43 +0900 Jeongjun Park <aha310510@gmail.com> wrote:

> > Therefore, when calling generic_fillattr() from shmem_getattr(), it is
> > appropriate to protect the inode using inode_lock_shared() and
> > inode_unlock_shared() to prevent data-race.
> >
> 
> Cc: stable@vger.kernel.org
> 
> I think this patch should be applied from next rc version and also stable
> version. When calling generic_fillattr(), if you don't hold read lock,
> data-race will occur in inode member variables, which can cause unexpected
> behavior. This problem is also present in several stable versions, so I think
> it should be fixed as soon as possible.

OK, thanks, I added the cc:stable amd moved this into the mm-hotfixes
pile for a 6.12-rcX merge.