Patch "perf/x86/intel/pt: Fix kernel address filter's offset validation" has been added to the 4.7-stable tree

This is a note to let you know that I've just added the patch titled

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

to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
perf-x86-intel-pt-fix-kernel-address-filter-s-offset-validation.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Alexander Shishkin <[email protected]>
Date: Thu, 15 Sep 2016 18:13:51 +0300
Subject: perf/x86/intel/pt: Fix kernel address filter's offset validation

From: Alexander Shishkin <[email protected]>

commit ddfdad991e55b65c1cc4ee29502f6dceee04455a upstream.

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.

---
 arch/x86/events/intel/pt.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

@@ -1074,6 +1074,11 @@ static void pt_addr_filters_fini(struct
 	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_validat
 		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))

Patches currently in stable-queue which might be from [email protected] are

queue-4.7/perf-x86-intel-pt-fix-an-off-by-one-in-address-filter-configuration.patch queue-4.7/perf-x86-intel-fix-pebsv3-record-drain.patch queue-4.7/perf-x86-intel-pt-do-validate-the-size-of-a-kernel-address-filter.patch queue-4.7/perf-x86-intel-pt-fix-kernel-address-filter-s-offset-validation.patch