Commit 23931d93 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'perf-urgent-2023-10-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 perf event fix from Ingo Molnar:
 "Fix an LBR sampling bug"

* tag 'perf-urgent-2023-10-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/lbr: Filter vsyscall addresses
parents 70f8c6f8 e5389977

arch/x86/events/utils.c

+3 −2
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#include <asm/insn.h>

#include <linux/mm.h>



#include "perf_event.h"
@@ -132,9 +133,9 @@ static int get_branch_type(unsigned long from, unsigned long to, int abort, 
		 * The LBR logs any address in the IP, even if the IP just

		 * faulted. This means userspace can control the from address.

		 * Ensure we don't blindly read any address by validating it is

		 * a known text address.

		 * a known text address and not a vsyscall address.

		 */

		if (kernel_text_address(from)) {

		if (kernel_text_address(from) && !in_gate_area_no_mm(from)) {

			addr = (void *)from;

			/*

			 * Assume we can get the maximum possible size