diff options
Diffstat (limited to 'arch/x86/entry/entry_64_compat.S')
| -rw-r--r-- | arch/x86/entry/entry_64_compat.S | 61 |
1 files changed, 52 insertions, 9 deletions
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index a7e257d9cb90..a9360d40fb7f 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -22,8 +22,8 @@ #define __AUDIT_ARCH_LE 0x40000000 #ifndef CONFIG_AUDITSYSCALL -# define sysexit_audit ia32_ret_from_sys_call -# define sysretl_audit ia32_ret_from_sys_call +# define sysexit_audit ia32_ret_from_sys_call_irqs_off +# define sysretl_audit ia32_ret_from_sys_call_irqs_off #endif .section .entry.text, "ax" @@ -141,7 +141,8 @@ sysexit_from_sys_call: andl $~TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS) movl RIP(%rsp), %ecx /* User %eip */ movq RAX(%rsp), %rax - RESTORE_RSI_RDI + movl RSI(%rsp), %esi + movl RDI(%rsp), %edi xorl %edx, %edx /* Do not leak kernel information */ xorq %r8, %r8 xorq %r9, %r9 @@ -209,10 +210,10 @@ sysexit_from_sys_call: .endm .macro auditsys_exit exit - testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS) - jnz ia32_ret_from_sys_call TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) + testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS) + jnz ia32_ret_from_sys_call movl %eax, %esi /* second arg, syscall return value */ cmpl $-MAX_ERRNO, %eax /* is it an error ? */ jbe 1f @@ -230,7 +231,7 @@ sysexit_from_sys_call: movq %rax, R10(%rsp) movq %rax, R9(%rsp) movq %rax, R8(%rsp) - jmp int_with_check + jmp int_ret_from_sys_call_irqs_off .endm sysenter_auditsys: @@ -365,7 +366,9 @@ cstar_dispatch: sysretl_from_sys_call: andl $~TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS) - RESTORE_RSI_RDI_RDX + movl RDX(%rsp), %edx + movl RSI(%rsp), %esi + movl RDI(%rsp), %edi movl RIP(%rsp), %ecx movl EFLAGS(%rsp), %r11d movq RAX(%rsp), %rax @@ -430,8 +433,48 @@ cstar_tracesys: END(entry_SYSCALL_compat) ia32_badarg: - ASM_CLAC - movq $-EFAULT, RAX(%rsp) + /* + * So far, we've entered kernel mode, set AC, turned on IRQs, and + * saved C regs except r8-r11. We haven't done any of the other + * standard entry work, though. We want to bail, but we shouldn't + * treat this as a syscall entry since we don't even know what the + * args are. Instead, treat this as a non-syscall entry, finish + * the entry work, and immediately exit after setting AX = -EFAULT. + * + * We're really just being polite here. Killing the task outright + * would be a reasonable action, too. Given that the only valid + * way to have gotten here is through the vDSO, and we already know + * that the stack pointer is bad, the task isn't going to survive + * for long no matter what we do. + */ + + ASM_CLAC /* undo STAC */ + movq $-EFAULT, RAX(%rsp) /* return -EFAULT if possible */ + + /* Fill in the rest of pt_regs */ + xorl %eax, %eax + movq %rax, R11(%rsp) + movq %rax, R10(%rsp) + movq %rax, R9(%rsp) + movq %rax, R8(%rsp) + SAVE_EXTRA_REGS + + /* Turn IRQs back off. */ + DISABLE_INTERRUPTS(CLBR_NONE) + TRACE_IRQS_OFF + + /* Now finish entering normal kernel mode. */ +#ifdef CONFIG_CONTEXT_TRACKING + call enter_from_user_mode +#endif + + /* And exit again. */ + jmp retint_user + +ia32_ret_from_sys_call_irqs_off: + TRACE_IRQS_ON + ENABLE_INTERRUPTS(CLBR_NONE) + ia32_ret_from_sys_call: xorl %eax, %eax /* Do not leak kernel information */ movq %rax, R11(%rsp) |