2018-07-12 17:21:45

by Boris Ostrovsky

Subject: [PATCH] xen/x86/vpmu: Zero struct pt_regs before calling into sample handling code

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

Reported-by: Mark Rutland <[email protected]>
Signed-off-by: Boris Ostrovsky <[email protected]>
Cc: [email protected]
---
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 7d00d4a..95997e6 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();

--
1.8.3.1

2018-07-13 08:44:42

by Jürgen Groß

Subject: Re: [PATCH] xen/x86/vpmu: Zero struct pt_regs before calling into sample handling code

On 12/07/18 19:27, Boris Ostrovsky wrote:
> Otherwise we may leak kernel stack for events that sample user
> registers.
>
> Reported-by: Mark Rutland <[email protected]>
> Signed-off-by: Boris Ostrovsky <[email protected]>
> Cc: [email protected]

Reviewed-by: Juergen Gross <[email protected]>


Juergen

2018-09-20 16:56:48

by Boris Ostrovsky

Subject: Re: [PATCH] xen/x86/vpmu: Zero struct pt_regs before calling into sample handling code

On 7/13/18 4:41 AM, Juergen Gross wrote:
> On 12/07/18 19:27, Boris Ostrovsky wrote:
>> Otherwise we may leak kernel stack for events that sample user
>> registers.
>>
>> Reported-by: Mark Rutland <[email protected]>
>> Signed-off-by: Boris Ostrovsky <[email protected]>
>> Cc: [email protected]
> Reviewed-by: Juergen Gross <[email protected]>
>

Belatedly, applied to for-linus-4.19d

-boris