From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Date: Thu, 12 Jul 2018 13:27:00 -0400
Subject: xen/x86/vpmu: Zero struct pt_regs before calling into sample handling
 code
Git-commit: 70513d58751d7c6c1a0133557b13089b9f2e3e66
Patch-mainline: v4.19-rc5
References: bsc#1110006

Otherwise we may leak kernel stack for events that sample user
registers.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org

Acked-by: Joerg Roedel <jroedel@suse.de>
---
 arch/x86/xen/pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/xen/pmu.c b/arch/x86/xen/pmu.c
index 7d00d4ad44d4..95997e6c0696 100644
--- a/arch/x86/xen/pmu.c
+++ b/arch/x86/xen/pmu.c
@@ -478,7 +478,7 @@ static void xen_convert_regs(const struct xen_pmu_regs *xen_regs,
 irqreturn_t xen_pmu_irq_handler(int irq, void *dev_id)
 {
 	int err, ret = IRQ_NONE;
-	struct pt_regs regs;
+	struct pt_regs regs = {0};
 	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
 	uint8_t xenpmu_flags = get_xenpmu_flags();