diff options
authorAlexander Shishkin <alexander.shishkin@linux.intel.com>2016-09-15 18:13:51 +0300
committerIngo Molnar <mingo@kernel.org>2016-09-16 11:14:16 +0200
commitddfdad991e55b65c1cc4ee29502f6dceee04455a (patch)
parent95f60084acbcee6c466256cf26eb52191fad9edc (diff)
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@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: stable@vger.kernel.org # v4.7 Cc: stable@vger.kernel.org#v4.7 Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160915151352.21306-3-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
index 5ec0100e3fc6..1f94963a283b 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)
- 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))