From: Jiri Kosina <jikos@kernel.org>
To: "Schaufler, Casey" <casey.schaufler@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Andrea Arcangeli <aarcange@redhat.com>,
"Woodhouse, David" <dwmw@amazon.co.uk>,
Andi Kleen <ak@linux.intel.com>,
Tim Chen <tim.c.chen@linux.intel.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"x86@kernel.org" <x86@kernel.org>
Subject: RE: [PATCH v6 1/3] x86/speculation: apply IBPB more strictly to avoid cross-process data leak
Date: Fri, 14 Sep 2018 13:00:40 +0200 (CEST) [thread overview]
Message-ID: <nycvar.YFH.7.76.1809141259010.15880@cbobk.fhfr.pm> (raw)
In-Reply-To: <99FC4B6EFCEFD44486C35F4C281DC6732144BFBC@ORSMSX107.amr.corp.intel.com>
On Thu, 13 Sep 2018, Schaufler, Casey wrote:
> > - return security_ptrace_access_check(task, mode);
> > + if (!(mode & PTRACE_MODE_NOACCESS_CHK))
> > + return security_ptrace_access_check(task, mode);
> > + return 0;
>
> Because PTRACE_MODE_IBPB includes PTRACE_MODE_NOAUDIT you
> shouldn't need this change.
That is true, but that's not my concern here.
security_ptrace_access_check() -> call_int_hook() -> P->hook.FUNC().
If it's somehow guaranteed that all functions called this ways are fine to
be called from scheduler context (wrt. locks), then it's all fine and I'll
happily drop that check.
Is it guaranteed?
Thanks,
--
Jiri Kosina
SUSE Labs
next prev parent reply other threads:[~2018-09-14 11:00 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-10 9:22 [PATCH v5 0/2] Harden spectrev2 userspace-userspace protection Jiri Kosina
2018-09-10 9:23 ` [PATCH v5 1/2] x86/speculation: apply IBPB more strictly to avoid cross-process data leak Jiri Kosina
2018-09-10 18:26 ` Schaufler, Casey
2018-09-10 19:14 ` Jiri Kosina
2018-09-10 19:26 ` Schaufler, Casey
2018-09-10 19:36 ` Jiri Kosina
2018-09-10 20:27 ` Schaufler, Casey
2018-09-10 20:42 ` Jiri Kosina
2018-09-10 21:29 ` Schaufler, Casey
2018-09-10 21:36 ` Jiri Kosina
2018-09-11 21:15 ` Thomas Gleixner
2018-09-11 22:25 ` Schaufler, Casey
2018-09-12 12:01 ` Thomas Gleixner
2018-10-21 19:38 ` Pavel Machek
2018-10-21 23:32 ` Jiri Kosina
2018-09-10 9:24 ` [PATCH v5 2/2] x86/speculation: Enable cross-hyperthread spectre v2 STIBP mitigation Jiri Kosina
2018-09-10 10:04 ` Thomas Gleixner
2018-09-10 11:01 ` Jiri Kosina
2018-09-10 11:46 ` Jiri Kosina
2018-09-11 17:32 ` Tim Chen
2018-09-11 21:16 ` Thomas Gleixner
2018-09-11 21:46 ` Thomas Gleixner
2018-09-12 17:16 ` Tom Lendacky
2018-09-12 21:26 ` Tim Chen
2018-09-12 21:45 ` Jiri Kosina
2018-09-12 22:56 ` Tim Chen
2018-09-13 14:53 ` Tom Lendacky
2018-09-12 9:05 ` [PATCH v6 0/3] Harden spectrev2 userspace-userspace protection Jiri Kosina
2018-09-12 9:06 ` [PATCH v6 1/3] x86/speculation: apply IBPB more strictly to avoid cross-process data leak Jiri Kosina
2018-09-13 0:04 ` Schaufler, Casey
2018-09-14 11:00 ` Jiri Kosina [this message]
2018-09-14 11:05 ` Thomas Gleixner
2018-09-12 9:07 ` [PATCH v6 2/3] x86/speculation: Enable cross-hyperthread spectre v2 STIBP mitigation Jiri Kosina
2018-09-12 19:14 ` Thomas Gleixner
2018-09-12 19:16 ` Jiri Kosina
2018-09-12 9:08 ` [PATCH v6 3/3] x86/speculation: Propagate information about RSB filling mitigation to sysfs Jiri Kosina
2018-09-17 16:09 ` [PATCH v6 0/3] Harden spectrev2 userspace-userspace protection Schaufler, Casey
2018-09-19 15:48 ` Peter Zijlstra
2018-09-22 7:38 ` Jiri Kosina
2018-09-22 9:53 ` Thomas Gleixner
2018-09-22 10:18 ` Peter Zijlstra
2018-09-22 10:20 ` Thomas Gleixner
2018-09-22 13:30 ` Thomas Gleixner
2018-09-22 14:31 ` Peter Zijlstra
2018-09-24 8:43 ` Jiri Kosina
2018-09-24 12:38 ` Thomas Gleixner
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