perf/x86/intel/pt: Fix an off-by-one in address filter configuration

PT address filter configuration requires that a range is specified by
its first and last address, but at the moment we're obtaining the end
of the range by adding user specified size to its start, which is off
by one from what it actually needs to be.

Fix this and make sure that zero-sized filters don't pass the filter
validation.

Reported-by: Adrian Hunter <[email protected]>
Signed-off-by: Alexander Shishkin <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Cc: [email protected] # v4.7
Cc: [email protected]#v4.7
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
index 04bb5fb5a8d7a13308fdcc20d2c1a5930146f07f..5ec0100e3fc66ecc1d11501715b34dc49eda4d4b 100644 (file)
--- a/arch/x86/events/intel/pt.c
+++ b/arch/x86/events/intel/pt.c
@@ -1081,7 +1081,7 @@ static int pt_event_addr_filters_validate(struct list_head *filters)
 
        list_for_each_entry(filter, filters, entry) {
                /* PT doesn't support single address triggers */
-               if (!filter->range)
+               if (!filter->range || !filter->size)
                        return -EOPNOTSUPP;
 
                if (!filter->inode && !kernel_ip(filter->offset))
@@ -1111,7 +1111,7 @@ static void pt_event_addr_filters_sync(struct perf_event *event)
                } else {
                        /* apply the offset */
                        msr_a = filter->offset + offs[range];
-                       msr_b = filter->size + msr_a;
+                       msr_b = filter->size + msr_a - 1;
                }
 
                filters->filter[range].msr_a  = msr_a;