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Subject[GIT PULL] perf events fix

Linus,

Please pull the latest perf/urgent git tree from:

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

# HEAD: e53899771a02f798d436655efbd9d4b46c0f9265 perf/x86/lbr: Filter vsyscall addresses

Fix an LBR sampling bug.

Thanks,

Ingo

------------------>
JP Kobryn (1):
perf/x86/lbr: Filter vsyscall addresses


arch/x86/events/utils.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/events/utils.c b/arch/x86/events/utils.c
index 76b1f8bb0fd5..dab4ed199227 100644
--- a/arch/x86/events/utils.c
+++ b/arch/x86/events/utils.c
@@ -1,5 +1,6 @@
// 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
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