From: Ondrej Mosnacek <omosnace@redhat.com>
To: Christoph Hellwig <hch@lst.de>, Ian Kent <raven@themaw.net>
Cc: autofs@vger.kernel.org,
Linux Security Module list
<linux-security-module@vger.kernel.org>,
SElinux list <selinux@vger.kernel.org>,
Zdenek Pytela <zpytela@redhat.com>
Subject: Commit 13c164b1a186 - regression for LSMs/SELinux?
Date: Mon, 21 Sep 2020 16:51:35 +0200 [thread overview]
Message-ID: <CAFqZXNsoXr1eA4C8==Nvujs5ONpRnuSqaOQQ0n78R=Dbm-EFGA@mail.gmail.com> (raw)
Hi folks,
It seems that after commit 13c164b1a186 ("autofs: switch to
kernel_write") there is now an extra LSM permission required (for the
current task to write to the automount pipe) for processes accessing
some yet-to-to-be mounted directory on which an autofs mount is set
up. The call chain is:
[...]
autofs_wait() ->
autofs_notify_daemon() ->
autofs_write() ->
kernel_write() ->
rw_verify_area() ->
security_file_permission()
The bug report that led me to this commit is at [1].
Technically, this is a regression for LSM users, since this is a
kernel-internal operation and an LSM permission for the current task
shouldn't be required. Can this patch be reverted? Perhaps
__kernel_{read|write}() could instead be renamed to kernel_*_nocheck()
so that the name is more descriptive?
Thanks,
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1874338
--
Ondrej Mosnacek
Software Engineer, Platform Security - SELinux kernel
Red Hat, Inc.
next reply other threads:[~2020-09-21 14:51 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-21 14:51 Ondrej Mosnacek [this message]
2020-09-21 16:09 ` Commit 13c164b1a186 - regression for LSMs/SELinux? Christoph Hellwig
2020-09-21 16:27 ` Linus Torvalds
2020-09-21 16:30 ` Al Viro
2020-09-22 0:30 ` Ian Kent
2020-09-22 1:35 ` Ian Kent
2020-09-22 7:33 ` Ondrej Mosnacek
2020-09-22 12:29 ` Stephen Smalley
2020-09-23 1:55 ` Ian Kent
2020-09-24 8:36 ` Ondrej Mosnacek
2020-09-24 9:47 ` Ian Kent
2020-09-24 14:16 ` Stephen Smalley
2020-09-25 3:37 ` Ian Kent
2020-09-25 3:44 ` Ian Kent
2020-09-25 13:37 ` Ondrej Mosnacek
2020-09-25 17:38 ` Linus Torvalds
2020-09-27 3:07 ` Ian Kent
2020-09-29 12:16 ` Ondrej Mosnacek
2020-09-29 17:23 ` Linus Torvalds
2020-09-29 18:00 ` Christoph Hellwig
2020-09-30 5:50 ` Ian Kent
2020-09-30 10:39 ` Ian Kent
2020-09-30 5:42 ` Ian Kent
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