diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/entry/calling.h | 14 | ||||
| -rw-r--r-- | arch/x86/entry/entry_32.S | 7 | ||||
| -rw-r--r-- | arch/x86/entry/entry_64.S | 3 | ||||
| -rw-r--r-- | arch/x86/entry/entry_64_compat.S | 5 |
5 files changed, 30 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 1a0be022f91d..662cb2cc9630 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -127,6 +127,7 @@ config X86 select HAVE_ARCH_PREL32_RELOCATIONS select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_THREAD_STRUCT_WHITELIST + select HAVE_ARCH_STACKLEAK select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index 352e70cd33e8..20d0885b00fb 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -329,8 +329,22 @@ For 32-bit we have the following conventions - kernel is built with #endif +.macro STACKLEAK_ERASE_NOCLOBBER +#ifdef CONFIG_GCC_PLUGIN_STACKLEAK + PUSH_AND_CLEAR_REGS + call stackleak_erase + POP_REGS +#endif +.endm + #endif /* CONFIG_X86_64 */ +.macro STACKLEAK_ERASE +#ifdef CONFIG_GCC_PLUGIN_STACKLEAK + call stackleak_erase +#endif +.endm + /* * This does 'call enter_from_user_mode' unless we can avoid it based on * kernel config or using the static jump infrastructure. diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 2767c625a52c..dfb975b4c981 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -46,6 +46,8 @@ #include <asm/frame.h> #include <asm/nospec-branch.h> +#include "calling.h" + .section .entry.text, "ax" /* @@ -711,6 +713,7 @@ ENTRY(ret_from_fork) /* When we fork, we trace the syscall return in the child, too. */ movl %esp, %eax call syscall_return_slowpath + STACKLEAK_ERASE jmp restore_all /* kernel thread */ @@ -885,6 +888,8 @@ ENTRY(entry_SYSENTER_32) ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \ "jmp .Lsyscall_32_done", X86_FEATURE_XENPV + STACKLEAK_ERASE + /* Opportunistic SYSEXIT */ TRACE_IRQS_ON /* User mode traces as IRQs on. */ @@ -996,6 +1001,8 @@ ENTRY(entry_INT80_32) call do_int80_syscall_32 .Lsyscall_32_done: + STACKLEAK_ERASE + restore_all: TRACE_IRQS_IRET SWITCH_TO_ENTRY_STACK diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 957dfb693ecc..a5dd28093020 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -329,6 +329,8 @@ syscall_return_via_sysret: * We are on the trampoline stack. All regs except RDI are live. * We can do future final exit work right here. */ + STACKLEAK_ERASE_NOCLOBBER + SWITCH_TO_USER_CR3_STACK scratch_reg=%rdi popq %rdi @@ -688,6 +690,7 @@ GLOBAL(swapgs_restore_regs_and_return_to_usermode) * We are on the trampoline stack. All regs except RDI are live. * We can do future final exit work right here. */ + STACKLEAK_ERASE_NOCLOBBER SWITCH_TO_USER_CR3_STACK scratch_reg=%rdi diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 7d0df78db727..8eaf8952c408 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -261,6 +261,11 @@ GLOBAL(entry_SYSCALL_compat_after_hwframe) /* Opportunistic SYSRET */ sysret32_from_system_call: + /* + * We are not going to return to userspace from the trampoline + * stack. So let's erase the thread stack right now. + */ + STACKLEAK_ERASE TRACE_IRQS_ON /* User mode traces as IRQs on. */ movq RBX(%rsp), %rbx /* pt_regs->rbx */ movq RBP(%rsp), %rbp /* pt_regs->rbp */ |