linux-kernel - [PATCH 0/2] perf/x86/intel: Work around BTS leaking kernel addresses

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1440688422-27954-1-git-send-email-alexander.shishkin@linux.intel.com>
Date:	Thu, 27 Aug 2015 18:13:40 +0300
From:	Alexander Shishkin <alexander.shishkin@...ux.intel.com>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc:	Ingo Molnar <mingo@...hat.com>, linux-kernel@...r.kernel.org,
	Arnaldo Carvalho de Melo <acme@...radead.org>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>
Subject: [PATCH 0/2] perf/x86/intel: Work around BTS leaking kernel addresses

Hi Peter,

Due to imprecise IP sampling, BTS may (and often does) leak kernel
addresses when kernel tracing is not even enabled, which results in
mostly syscall entry points and page_fault handler addresses being
exposed. This might be a security concern for the address
randomization, and it also makes life harder for gdb that makes use of
bts samples.

This patchset works around the old (DS) driver and disables the new
(intel_bts) for the unprivileged users on systems where perf paranoia
level prohibits kernel tracing.

Not sure if these should be treated as bugfixes.

Alexander Shishkin (2):
  perf/x86/intel/ds: Work around BTS leaking kernel addresses
  perf/x86/intel/bts: Disallow use by unprivileged users on paranoid
    systems

 arch/x86/kernel/cpu/perf_event_intel_bts.c | 10 ++++++++
 arch/x86/kernel/cpu/perf_event_intel_ds.c  | 40 +++++++++++++++++++++++++-----
 2 files changed, 44 insertions(+), 6 deletions(-)

-- 
2.5.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/