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Date:   Sat, 1 Jun 2019 03:25:27 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Gen Zhang <blackgod016574@gmail.com>
Cc:     paul@paul-moore.com, sds@tycho.nsa.gov, eparis@parisplace.org,
        omosnace@redhat.com, selinux@vger.kernel.org,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        bpf@vger.kernel.org
Subject: Re: [PATCH v3] selinux: lsm: fix a missing-check bug in
 selinux_sb_eat_lsm_opts()
Message-ID: <20190601022527.GR17978@ZenIV.linux.org.uk>
References: <20190601021526.GA8264@zhanggen-UX430UQ>
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On Sat, Jun 01, 2019 at 10:15:26AM +0800, Gen Zhang wrote:
> In selinux_sb_eat_lsm_opts(), 'arg' is allocated by kmemdup_nul(). It
> returns NULL when fails. So 'arg' should be checked. And 'mnt_opts' 
> should be freed when error.

What's the latter one for?  On failure we'll get to put_fs_context()
pretty soon, so
        security_free_mnt_opts(&fc->security);
will be called just fine.  Leaving it allocated on failure is fine...