Re: [PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-11 Thread Josh Poimboeuf
On Tue, Jan 09, 2018 at 05:03:23PM -0800, Andi Kleen wrote: > From: Andi Kleen > > We clear all the non argument registers for 64bit SYSCALLs > to minimize any risk of bad speculation using user values. > > So far unused argument registers still leak. To be addressed > in

Re: [PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-11 Thread Josh Poimboeuf
On Tue, Jan 09, 2018 at 05:03:23PM -0800, Andi Kleen wrote: > From: Andi Kleen > > We clear all the non argument registers for 64bit SYSCALLs > to minimize any risk of bad speculation using user values. > > So far unused argument registers still leak. To be addressed > in future patches. > >

Re: [PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-11 Thread Andi Kleen
On Wed, Jan 10, 2018 at 10:35:58PM -0500, Brian Gerst wrote: > > @@ -263,6 +271,7 @@ entry_SYSCALL_64_fastpath: > > #endif > > ja 1f /* return -ENOSYS (already > > in pt_regs->ax) */ > > movq%r10, %rcx > > + xor %r10, %r10 > > RCX

Re: [PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-11 Thread Andi Kleen
On Wed, Jan 10, 2018 at 10:35:58PM -0500, Brian Gerst wrote: > > @@ -263,6 +271,7 @@ entry_SYSCALL_64_fastpath: > > #endif > > ja 1f /* return -ENOSYS (already > > in pt_regs->ax) */ > > movq%r10, %rcx > > + xor %r10, %r10 > > RCX

Re: [PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-10 Thread Brian Gerst
On Tue, Jan 9, 2018 at 8:03 PM, Andi Kleen wrote: > From: Andi Kleen > > We clear all the non argument registers for 64bit SYSCALLs > to minimize any risk of bad speculation using user values. > > So far unused argument registers still leak. To be

Re: [PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-10 Thread Brian Gerst
On Tue, Jan 9, 2018 at 8:03 PM, Andi Kleen wrote: > From: Andi Kleen > > We clear all the non argument registers for 64bit SYSCALLs > to minimize any risk of bad speculation using user values. > > So far unused argument registers still leak. To be addressed > in future patches. > >

[PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-09 Thread Andi Kleen
From: Andi Kleen We clear all the non argument registers for 64bit SYSCALLs to minimize any risk of bad speculation using user values. So far unused argument registers still leak. To be addressed in future patches. Signed-off-by: Andi Kleen ---

[PATCH v1 3/8] x86/entry/clearregs: Clear registers for 64bit SYSCALL

2018-01-09 Thread Andi Kleen
From: Andi Kleen We clear all the non argument registers for 64bit SYSCALLs to minimize any risk of bad speculation using user values. So far unused argument registers still leak. To be addressed in future patches. Signed-off-by: Andi Kleen --- arch/x86/entry/entry_64.S | 9 + 1 file