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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 9b4fbd89-f70c-4462-79a3-08d7d0b62bb6 X-MS-Exchange-CrossTenant-originalarrivaltime: 25 Mar 2020 12:15:12.9820 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 9BUpkDalH6Xfnn9q/Z4fatBvI6iYdf5wUeTPr7aT+6vnesukWh+gAF4FEkKMS4KS4GMmteUqxdITni7Y6iZK8dHgLLKOWqP5PLikRjEu6Ew= X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL0PR11MB3220 X-OriginatorOrg: intel.com > > Also, are you sure that it isn't possible to make the syscall that > > leaked its stack pointer never return to userspace (via ptrace or > > SIGSTOP or something like that), and therefore never realign its > > stack, while keeping some controlled data present on the syscall's > > stack? How would you reliably detect that a stack pointer has been leaked to userspace while it has been in a syscall? Does not seem to be a trivial task to me.=20 Best Regards, Elena.=20