From 1155bafcb79208abc6ae234c6e135ac70607755c Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Thu, 15 Sep 2016 18:13:52 +0300 Subject: perf/x86/intel/pt: Do validate the size of a kernel address filter Right now, the kernel address filters in PT are prone to integer overflow that may happen in adding filter's size to its offset to obtain the end of the range. Such an overflow would also throw a #GP in the PT event configuration path. Fix this by explicitly validating the result of this calculation. Reported-by: Adrian Hunter Signed-off-by: Alexander Shishkin Acked-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: stable@vger.kernel.org # v4.7 Cc: stable@vger.kernel.org#v4.7 Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160915151352.21306-4-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/events/intel/pt.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 1f94963a283b..861a7d9cb60f 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -1089,8 +1089,13 @@ static int pt_event_addr_filters_validate(struct list_head *filters) if (!filter->range || !filter->size) return -EOPNOTSUPP; - if (!filter->inode && !valid_kernel_ip(filter->offset)) - return -EINVAL; + if (!filter->inode) { + if (!valid_kernel_ip(filter->offset)) + return -EINVAL; + + if (!valid_kernel_ip(filter->offset + filter->size)) + return -EINVAL; + } if (++range > pt_cap_get(PT_CAP_num_address_ranges)) return -EOPNOTSUPP; -- cgit v1.2.3