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: <20130318134645.GA3278@quad>
Date:	Mon, 18 Mar 2013 14:46:45 +0100
From:	Stephane Eranian <eranian@...gle.com>
To:	linux-kernel@...r.kernel.org
Cc:	peterz@...radead.org, mingo@...e.hu, jolsa@...hat.com,
	sqazi@...gle.com, ak@...ux.intel.com
Subject: [PATCH] perf,x86: fix uninitialized pt_regs in
 intel_pmu_drain_bts_buffer()



This patch fixes an uninitialized pt_regs struct in drain BTS
function. The pt_regs struct is propagated all the way to the
code_get_segment() function from perf_instruction_pointer()
and may get garbage.

We cannot simply inherit the actual pt_regs from the interrupt
because BTS must be flushed on context-switch or when the associated
event is disabled. And there we do not have a pt_regs handy.

Setting pt_regs to all zeroes may not be the best option but it is
not clear what else to do given where the drain_bts_buffer() is called
from.

Signed-off-by: Stephane Eranian <eranian@...gle.com>
---

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index b05a575..208f0c8 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -302,6 +302,8 @@ int intel_pmu_drain_bts_buffer(void)
 	struct perf_sample_data data;
 	struct pt_regs regs;
 
+	memset(&regs, 0, sizeof(regs));
+
 	if (!event)
 		return 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/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ