linux-kernel - [tip:perf/urgent] perf/x86/intel/pt: Fix kernel address filter's offset validation

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

Date:   Fri, 16 Sep 2016 04:58:30 -0700
From:   tip-bot for Alexander Shishkin <tipbot@...or.com>
To:     linux-tip-commits@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org, acme@...radead.org,
        tglx@...utronix.de, jolsa@...hat.com, hpa@...or.com,
        a.p.zijlstra@...llo.nl, peterz@...radead.org, eranian@...gle.com,
        acme@...hat.com, vincent.weaver@...ne.edu,
        alexander.shishkin@...ux.intel.com, torvalds@...ux-foundation.org,
        adrian.hunter@...el.com, mingo@...nel.org
Subject: [tip:perf/urgent] perf/x86/intel/pt: Fix kernel address filter's
 offset validation

Commit-ID:  ddfdad991e55b65c1cc4ee29502f6dceee04455a
Gitweb:     http://git.kernel.org/tip/ddfdad991e55b65c1cc4ee29502f6dceee04455a
Author:     Alexander Shishkin <alexander.shishkin@...ux.intel.com>
AuthorDate: Thu, 15 Sep 2016 18:13:51 +0300
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Fri, 16 Sep 2016 11:14:16 +0200

perf/x86/intel/pt: Fix kernel address filter's offset validation

The kernel_ip() filter is used mostly by the DS/LBR code to look at the
branch addresses, but Intel PT also uses it to validate the address
filter offsets for kernel addresses, for which it is not sufficient:
supplying something in bits 64:48 that's not a sign extension of the lower
address bits (like 0xf00d000000000000) throws a #GP.

This patch adds address validation for the user supplied kernel filters.

Reported-by: Adrian Hunter <adrian.hunter@...el.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@...ux.intel.com>
Acked-by: Peter Zijlstra <peterz@...radead.org>
Cc: Arnaldo Carvalho de Melo <acme@...radead.org>
Cc: Arnaldo Carvalho de Melo <acme@...hat.com>
Cc: Jiri Olsa <jolsa@...hat.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc: Stephane Eranian <eranian@...gle.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Vince Weaver <vincent.weaver@...ne.edu>
Cc: stable@...r.kernel.org # v4.7
Cc: stable@...r.kernel.org#v4.7
Cc: vince@...ter.net
Link: http://lkml.kernel.org/r/20160915151352.21306-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 arch/x86/events/intel/pt.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
index 5ec0100..1f94963 100644
--- a/arch/x86/events/intel/pt.c
+++ b/arch/x86/events/intel/pt.c
@@ -1074,6 +1074,11 @@ static void pt_addr_filters_fini(struct perf_event *event)
 	event->hw.addr_filters = NULL;
 }
 
+static inline bool valid_kernel_ip(unsigned long ip)
+{
+	return virt_addr_valid(ip) && kernel_ip(ip);
+}
+
 static int pt_event_addr_filters_validate(struct list_head *filters)
 {
 	struct perf_addr_filter *filter;
@@ -1084,7 +1089,7 @@ static int pt_event_addr_filters_validate(struct list_head *filters)
 		if (!filter->range || !filter->size)
 			return -EOPNOTSUPP;
 
-		if (!filter->inode && !kernel_ip(filter->offset))
+		if (!filter->inode && !valid_kernel_ip(filter->offset))
 			return -EINVAL;
 
 		if (++range > pt_cap_get(PT_CAP_num_address_ranges))