From: Al Viro <viro@ZenIV.linux.org.uk>
To: Gargi Sharma <gs051095@gmail.com>
Cc: linux-kernel@vger.kernel.org, riel@surriel.com,
julia.lawall@lip6.fr, akpm@linux-foundation.org,
mingo@kernel.org, pasha.tatashin@oracle.com,
ktkhai@virtuozzo.com, oleg@redhat.com,
wangkefeng.wang@park.jinmi.com
Subject: Re: [RFC 1/2] proc: Return if nothing to unmount
Date: Sat, 9 Sep 2017 19:31:35 +0100 [thread overview]
Message-ID: <20170909183135.GB5426@ZenIV.linux.org.uk> (raw)
In-Reply-To: <c07a54336db555d29519d16c60e77b199907d97b.1504952909.git.gs051095@gmail.com>
On Sat, Sep 09, 2017 at 06:03:16PM +0530, Gargi Sharma wrote:
> If a task exits before procfs is mounted, proc_flush_task_mnt will
> be called with a NULL mnt parameter. In that case, not only is there
> nothing to unhash, but trying to do so will oops the kernel with a
> null pointer dereference.
You are misreading that sucker. It's about userland mounts, it's about
the internal ones in pidns, for each pidns the process belongs to.
IOW, what you are adding is dead code. The very first alloc_pid() in
that pidns should've called pid_ns_prepare_proc(), which creates that
vfsmount.
next prev parent reply other threads:[~2017-09-09 18:31 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-09 12:33 [RFC 0/2] Replace PID implementation with IDR API Gargi Sharma
2017-09-09 12:33 ` [RFC 1/2] proc: Return if nothing to unmount Gargi Sharma
2017-09-09 18:31 ` Al Viro [this message]
2017-09-10 19:41 ` Rik van Riel
2017-09-11 0:58 ` Rik van Riel
2017-09-09 12:33 ` [RFC 2/2] pid: Replace PID bitmap implementation with IDR API Gargi Sharma
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