| /* |
| * Compatibility mode system call entry point for x86-64. |
| * |
| * Copyright 2000-2002 Andi Kleen, SuSE Labs. |
| */ |
| |
| #include <asm/dwarf2.h> |
| #include <asm/calling.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/current.h> |
| #include <asm/errno.h> |
| #include <asm/ia32_unistd.h> |
| #include <asm/thread_info.h> |
| #include <asm/segment.h> |
| #include <asm/irqflags.h> |
| #include <asm/asm.h> |
| #include <asm/smap.h> |
| #include <linux/linkage.h> |
| #include <linux/err.h> |
| |
| /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ |
| #include <linux/elf-em.h> |
| #define AUDIT_ARCH_I386 (EM_386|__AUDIT_ARCH_LE) |
| #define __AUDIT_ARCH_LE 0x40000000 |
| |
| #ifndef CONFIG_AUDITSYSCALL |
| #define sysexit_audit ia32_ret_from_sys_call |
| #define sysretl_audit ia32_ret_from_sys_call |
| #endif |
| |
| .section .entry.text, "ax" |
| |
| .macro IA32_ARG_FIXUP noebp=0 |
| movl %edi,%r8d |
| .if \noebp |
| .else |
| movl %ebp,%r9d |
| .endif |
| xchg %ecx,%esi |
| movl %ebx,%edi |
| movl %edx,%edx /* zero extension */ |
| .endm |
| |
| /* clobbers %eax */ |
| .macro CLEAR_RREGS offset=0, _r9=rax |
| xorl %eax,%eax |
| movq %rax,\offset+R11(%rsp) |
| movq %rax,\offset+R10(%rsp) |
| movq %\_r9,\offset+R9(%rsp) |
| movq %rax,\offset+R8(%rsp) |
| .endm |
| |
| /* |
| * Reload arg registers from stack in case ptrace changed them. |
| * We don't reload %eax because syscall_trace_enter() returned |
| * the %rax value we should see. Instead, we just truncate that |
| * value to 32 bits again as we did on entry from user mode. |
| * If it's a new value set by user_regset during entry tracing, |
| * this matches the normal truncation of the user-mode value. |
| * If it's -1 to make us punt the syscall, then (u32)-1 is still |
| * an appropriately invalid value. |
| */ |
| .macro LOAD_ARGS32 offset, _r9=0 |
| .if \_r9 |
| movl \offset+16(%rsp),%r9d |
| .endif |
| movl \offset+40(%rsp),%ecx |
| movl \offset+48(%rsp),%edx |
| movl \offset+56(%rsp),%esi |
| movl \offset+64(%rsp),%edi |
| movl %eax,%eax /* zero extension */ |
| .endm |
| |
| .macro CFI_STARTPROC32 simple |
| CFI_STARTPROC \simple |
| CFI_UNDEFINED r8 |
| CFI_UNDEFINED r9 |
| CFI_UNDEFINED r10 |
| CFI_UNDEFINED r11 |
| CFI_UNDEFINED r12 |
| CFI_UNDEFINED r13 |
| CFI_UNDEFINED r14 |
| CFI_UNDEFINED r15 |
| .endm |
| |
| #ifdef CONFIG_PARAVIRT |
| ENTRY(native_usergs_sysret32) |
| swapgs |
| sysretl |
| ENDPROC(native_usergs_sysret32) |
| |
| ENTRY(native_irq_enable_sysexit) |
| swapgs |
| sti |
| sysexit |
| ENDPROC(native_irq_enable_sysexit) |
| #endif |
| |
| /* |
| * 32bit SYSENTER instruction entry. |
| * |
| * Arguments: |
| * %eax System call number. |
| * %ebx Arg1 |
| * %ecx Arg2 |
| * %edx Arg3 |
| * %esi Arg4 |
| * %edi Arg5 |
| * %ebp user stack |
| * 0(%ebp) Arg6 |
| * |
| * Interrupts off. |
| * |
| * This is purely a fast path. For anything complicated we use the int 0x80 |
| * path below. Set up a complete hardware stack frame to share code |
| * with the int 0x80 path. |
| */ |
| ENTRY(ia32_sysenter_target) |
| CFI_STARTPROC32 simple |
| CFI_SIGNAL_FRAME |
| CFI_DEF_CFA rsp,0 |
| CFI_REGISTER rsp,rbp |
| SWAPGS_UNSAFE_STACK |
| movq PER_CPU_VAR(kernel_stack), %rsp |
| addq $(KERNEL_STACK_OFFSET),%rsp |
| /* |
| * No need to follow this irqs on/off section: the syscall |
| * disabled irqs, here we enable it straight after entry: |
| */ |
| ENABLE_INTERRUPTS(CLBR_NONE) |
| movl %ebp,%ebp /* zero extension */ |
| pushq_cfi $__USER32_DS |
| /*CFI_REL_OFFSET ss,0*/ |
| pushq_cfi %rbp |
| CFI_REL_OFFSET rsp,0 |
| pushfq_cfi |
| /*CFI_REL_OFFSET rflags,0*/ |
| movl TI_sysenter_return+THREAD_INFO(%rsp,3*8-KERNEL_STACK_OFFSET),%r10d |
| CFI_REGISTER rip,r10 |
| pushq_cfi $__USER32_CS |
| /*CFI_REL_OFFSET cs,0*/ |
| movl %eax, %eax |
| pushq_cfi %r10 |
| CFI_REL_OFFSET rip,0 |
| pushq_cfi %rax |
| cld |
| SAVE_ARGS 0,1,0 |
| /* no need to do an access_ok check here because rbp has been |
| 32bit zero extended */ |
| ASM_STAC |
| 1: movl (%rbp),%ebp |
| _ASM_EXTABLE(1b,ia32_badarg) |
| ASM_CLAC |
| |
| /* |
| * Sysenter doesn't filter flags, so we need to clear NT |
| * ourselves. To save a few cycles, we can check whether |
| * NT was set instead of doing an unconditional popfq. |
| */ |
| testl $X86_EFLAGS_NT,EFLAGS-ARGOFFSET(%rsp) |
| jnz sysenter_fix_flags |
| sysenter_flags_fixed: |
| |
| orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| CFI_REMEMBER_STATE |
| jnz sysenter_tracesys |
| cmpq $(IA32_NR_syscalls-1),%rax |
| ja ia32_badsys |
| sysenter_do_call: |
| IA32_ARG_FIXUP |
| sysenter_dispatch: |
| call *ia32_sys_call_table(,%rax,8) |
| movq %rax,RAX-ARGOFFSET(%rsp) |
| DISABLE_INTERRUPTS(CLBR_NONE) |
| TRACE_IRQS_OFF |
| testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jnz sysexit_audit |
| sysexit_from_sys_call: |
| andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| /* clear IF, that popfq doesn't enable interrupts early */ |
| andl $~0x200,EFLAGS-R11(%rsp) |
| movl RIP-R11(%rsp),%edx /* User %eip */ |
| CFI_REGISTER rip,rdx |
| RESTORE_ARGS 0,24,0,0,0,0 |
| xorq %r8,%r8 |
| xorq %r9,%r9 |
| xorq %r10,%r10 |
| xorq %r11,%r11 |
| popfq_cfi |
| /*CFI_RESTORE rflags*/ |
| popq_cfi %rcx /* User %esp */ |
| CFI_REGISTER rsp,rcx |
| TRACE_IRQS_ON |
| ENABLE_INTERRUPTS_SYSEXIT32 |
| |
| CFI_RESTORE_STATE |
| |
| #ifdef CONFIG_AUDITSYSCALL |
| .macro auditsys_entry_common |
| movl %esi,%r8d /* 5th arg: 4th syscall arg */ |
| movl %ecx,%r9d /*swap with edx*/ |
| movl %edx,%ecx /* 4th arg: 3rd syscall arg */ |
| movl %r9d,%edx /* 3rd arg: 2nd syscall arg */ |
| movl %ebx,%esi /* 2nd arg: 1st syscall arg */ |
| movl %eax,%edi /* 1st arg: syscall number */ |
| call __audit_syscall_entry |
| movl RAX-ARGOFFSET(%rsp),%eax /* reload syscall number */ |
| cmpq $(IA32_NR_syscalls-1),%rax |
| ja ia32_badsys |
| movl %ebx,%edi /* reload 1st syscall arg */ |
| movl RCX-ARGOFFSET(%rsp),%esi /* reload 2nd syscall arg */ |
| movl RDX-ARGOFFSET(%rsp),%edx /* reload 3rd syscall arg */ |
| movl RSI-ARGOFFSET(%rsp),%ecx /* reload 4th syscall arg */ |
| movl RDI-ARGOFFSET(%rsp),%r8d /* reload 5th syscall arg */ |
| .endm |
| |
| .macro auditsys_exit exit |
| testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jnz ia32_ret_from_sys_call |
| TRACE_IRQS_ON |
| ENABLE_INTERRUPTS(CLBR_NONE) |
| movl %eax,%esi /* second arg, syscall return value */ |
| cmpl $-MAX_ERRNO,%eax /* is it an error ? */ |
| jbe 1f |
| movslq %eax, %rsi /* if error sign extend to 64 bits */ |
| 1: setbe %al /* 1 if error, 0 if not */ |
| movzbl %al,%edi /* zero-extend that into %edi */ |
| call __audit_syscall_exit |
| movq RAX-ARGOFFSET(%rsp),%rax /* reload syscall return value */ |
| movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi |
| DISABLE_INTERRUPTS(CLBR_NONE) |
| TRACE_IRQS_OFF |
| testl %edi,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jz \exit |
| CLEAR_RREGS -ARGOFFSET |
| jmp int_with_check |
| .endm |
| |
| sysenter_auditsys: |
| auditsys_entry_common |
| movl %ebp,%r9d /* reload 6th syscall arg */ |
| jmp sysenter_dispatch |
| |
| sysexit_audit: |
| auditsys_exit sysexit_from_sys_call |
| #endif |
| |
| sysenter_fix_flags: |
| pushq_cfi $(X86_EFLAGS_IF|X86_EFLAGS_FIXED) |
| popfq_cfi |
| jmp sysenter_flags_fixed |
| |
| sysenter_tracesys: |
| #ifdef CONFIG_AUDITSYSCALL |
| testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jz sysenter_auditsys |
| #endif |
| SAVE_REST |
| CLEAR_RREGS |
| movq $-ENOSYS,RAX(%rsp)/* ptrace can change this for a bad syscall */ |
| movq %rsp,%rdi /* &pt_regs -> arg1 */ |
| call syscall_trace_enter |
| LOAD_ARGS32 ARGOFFSET /* reload args from stack in case ptrace changed it */ |
| RESTORE_REST |
| cmpq $(IA32_NR_syscalls-1),%rax |
| ja int_ret_from_sys_call /* sysenter_tracesys has set RAX(%rsp) */ |
| jmp sysenter_do_call |
| CFI_ENDPROC |
| ENDPROC(ia32_sysenter_target) |
| |
| /* |
| * 32bit SYSCALL instruction entry. |
| * |
| * Arguments: |
| * %eax System call number. |
| * %ebx Arg1 |
| * %ecx return EIP |
| * %edx Arg3 |
| * %esi Arg4 |
| * %edi Arg5 |
| * %ebp Arg2 [note: not saved in the stack frame, should not be touched] |
| * %esp user stack |
| * 0(%esp) Arg6 |
| * |
| * Interrupts off. |
| * |
| * This is purely a fast path. For anything complicated we use the int 0x80 |
| * path below. Set up a complete hardware stack frame to share code |
| * with the int 0x80 path. |
| */ |
| ENTRY(ia32_cstar_target) |
| CFI_STARTPROC32 simple |
| CFI_SIGNAL_FRAME |
| CFI_DEF_CFA rsp,KERNEL_STACK_OFFSET |
| CFI_REGISTER rip,rcx |
| /*CFI_REGISTER rflags,r11*/ |
| SWAPGS_UNSAFE_STACK |
| movl %esp,%r8d |
| CFI_REGISTER rsp,r8 |
| movq PER_CPU_VAR(kernel_stack),%rsp |
| /* |
| * No need to follow this irqs on/off section: the syscall |
| * disabled irqs and here we enable it straight after entry: |
| */ |
| ENABLE_INTERRUPTS(CLBR_NONE) |
| SAVE_ARGS 8,0,0 |
| movl %eax,%eax /* zero extension */ |
| movq %rax,ORIG_RAX-ARGOFFSET(%rsp) |
| movq %rcx,RIP-ARGOFFSET(%rsp) |
| CFI_REL_OFFSET rip,RIP-ARGOFFSET |
| movq %rbp,RCX-ARGOFFSET(%rsp) /* this lies slightly to ptrace */ |
| movl %ebp,%ecx |
| movq $__USER32_CS,CS-ARGOFFSET(%rsp) |
| movq $__USER32_DS,SS-ARGOFFSET(%rsp) |
| movq %r11,EFLAGS-ARGOFFSET(%rsp) |
| /*CFI_REL_OFFSET rflags,EFLAGS-ARGOFFSET*/ |
| movq %r8,RSP-ARGOFFSET(%rsp) |
| CFI_REL_OFFSET rsp,RSP-ARGOFFSET |
| /* no need to do an access_ok check here because r8 has been |
| 32bit zero extended */ |
| /* hardware stack frame is complete now */ |
| ASM_STAC |
| 1: movl (%r8),%r9d |
| _ASM_EXTABLE(1b,ia32_badarg) |
| ASM_CLAC |
| orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| CFI_REMEMBER_STATE |
| jnz cstar_tracesys |
| cmpq $IA32_NR_syscalls-1,%rax |
| ja ia32_badsys |
| cstar_do_call: |
| IA32_ARG_FIXUP 1 |
| cstar_dispatch: |
| call *ia32_sys_call_table(,%rax,8) |
| movq %rax,RAX-ARGOFFSET(%rsp) |
| DISABLE_INTERRUPTS(CLBR_NONE) |
| TRACE_IRQS_OFF |
| testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jnz sysretl_audit |
| sysretl_from_sys_call: |
| andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| RESTORE_ARGS 0,-ARG_SKIP,0,0,0 |
| movl RIP-ARGOFFSET(%rsp),%ecx |
| CFI_REGISTER rip,rcx |
| movl EFLAGS-ARGOFFSET(%rsp),%r11d |
| /*CFI_REGISTER rflags,r11*/ |
| xorq %r10,%r10 |
| xorq %r9,%r9 |
| xorq %r8,%r8 |
| TRACE_IRQS_ON |
| movl RSP-ARGOFFSET(%rsp),%esp |
| CFI_RESTORE rsp |
| USERGS_SYSRET32 |
| |
| #ifdef CONFIG_AUDITSYSCALL |
| cstar_auditsys: |
| CFI_RESTORE_STATE |
| movl %r9d,R9-ARGOFFSET(%rsp) /* register to be clobbered by call */ |
| auditsys_entry_common |
| movl R9-ARGOFFSET(%rsp),%r9d /* reload 6th syscall arg */ |
| jmp cstar_dispatch |
| |
| sysretl_audit: |
| auditsys_exit sysretl_from_sys_call |
| #endif |
| |
| cstar_tracesys: |
| #ifdef CONFIG_AUDITSYSCALL |
| testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jz cstar_auditsys |
| #endif |
| xchgl %r9d,%ebp |
| SAVE_REST |
| CLEAR_RREGS 0, r9 |
| movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */ |
| movq %rsp,%rdi /* &pt_regs -> arg1 */ |
| call syscall_trace_enter |
| LOAD_ARGS32 ARGOFFSET, 1 /* reload args from stack in case ptrace changed it */ |
| RESTORE_REST |
| xchgl %ebp,%r9d |
| cmpq $(IA32_NR_syscalls-1),%rax |
| ja int_ret_from_sys_call /* cstar_tracesys has set RAX(%rsp) */ |
| jmp cstar_do_call |
| END(ia32_cstar_target) |
| |
| ia32_badarg: |
| ASM_CLAC |
| movq $-EFAULT,%rax |
| jmp ia32_sysret |
| CFI_ENDPROC |
| |
| /* |
| * Emulated IA32 system calls via int 0x80. |
| * |
| * Arguments: |
| * %eax System call number. |
| * %ebx Arg1 |
| * %ecx Arg2 |
| * %edx Arg3 |
| * %esi Arg4 |
| * %edi Arg5 |
| * %ebp Arg6 [note: not saved in the stack frame, should not be touched] |
| * |
| * Notes: |
| * Uses the same stack frame as the x86-64 version. |
| * All registers except %eax must be saved (but ptrace may violate that) |
| * Arguments are zero extended. For system calls that want sign extension and |
| * take long arguments a wrapper is needed. Most calls can just be called |
| * directly. |
| * Assumes it is only called from user space and entered with interrupts off. |
| */ |
| |
| ENTRY(ia32_syscall) |
| CFI_STARTPROC32 simple |
| CFI_SIGNAL_FRAME |
| CFI_DEF_CFA rsp,SS+8-RIP |
| /*CFI_REL_OFFSET ss,SS-RIP*/ |
| CFI_REL_OFFSET rsp,RSP-RIP |
| /*CFI_REL_OFFSET rflags,EFLAGS-RIP*/ |
| /*CFI_REL_OFFSET cs,CS-RIP*/ |
| CFI_REL_OFFSET rip,RIP-RIP |
| PARAVIRT_ADJUST_EXCEPTION_FRAME |
| SWAPGS |
| /* |
| * No need to follow this irqs on/off section: the syscall |
| * disabled irqs and here we enable it straight after entry: |
| */ |
| ENABLE_INTERRUPTS(CLBR_NONE) |
| movl %eax,%eax |
| pushq_cfi %rax |
| cld |
| /* note the registers are not zero extended to the sf. |
| this could be a problem. */ |
| SAVE_ARGS 0,1,0 |
| orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) |
| jnz ia32_tracesys |
| cmpq $(IA32_NR_syscalls-1),%rax |
| ja ia32_badsys |
| ia32_do_call: |
| IA32_ARG_FIXUP |
| call *ia32_sys_call_table(,%rax,8) # xxx: rip relative |
| ia32_sysret: |
| movq %rax,RAX-ARGOFFSET(%rsp) |
| ia32_ret_from_sys_call: |
| CLEAR_RREGS -ARGOFFSET |
| jmp int_ret_from_sys_call |
| |
| ia32_tracesys: |
| SAVE_REST |
| CLEAR_RREGS |
| movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */ |
| movq %rsp,%rdi /* &pt_regs -> arg1 */ |
| call syscall_trace_enter |
| LOAD_ARGS32 ARGOFFSET /* reload args from stack in case ptrace changed it */ |
| RESTORE_REST |
| cmpq $(IA32_NR_syscalls-1),%rax |
| ja int_ret_from_sys_call /* ia32_tracesys has set RAX(%rsp) */ |
| jmp ia32_do_call |
| END(ia32_syscall) |
| |
| ia32_badsys: |
| movq $0,ORIG_RAX-ARGOFFSET(%rsp) |
| movq $-ENOSYS,%rax |
| jmp ia32_sysret |
| |
| CFI_ENDPROC |
| |
| .macro PTREGSCALL label, func |
| ALIGN |
| GLOBAL(\label) |
| leaq \func(%rip),%rax |
| jmp ia32_ptregs_common |
| .endm |
| |
| CFI_STARTPROC32 |
| |
| PTREGSCALL stub32_rt_sigreturn, sys32_rt_sigreturn |
| PTREGSCALL stub32_sigreturn, sys32_sigreturn |
| PTREGSCALL stub32_execve, compat_sys_execve |
| PTREGSCALL stub32_fork, sys_fork |
| PTREGSCALL stub32_vfork, sys_vfork |
| |
| ALIGN |
| GLOBAL(stub32_clone) |
| leaq sys_clone(%rip),%rax |
| mov %r8, %rcx |
| jmp ia32_ptregs_common |
| |
| ALIGN |
| ia32_ptregs_common: |
| popq %r11 |
| CFI_ENDPROC |
| CFI_STARTPROC32 simple |
| CFI_SIGNAL_FRAME |
| CFI_DEF_CFA rsp,SS+8-ARGOFFSET |
| CFI_REL_OFFSET rax,RAX-ARGOFFSET |
| CFI_REL_OFFSET rcx,RCX-ARGOFFSET |
| CFI_REL_OFFSET rdx,RDX-ARGOFFSET |
| CFI_REL_OFFSET rsi,RSI-ARGOFFSET |
| CFI_REL_OFFSET rdi,RDI-ARGOFFSET |
| CFI_REL_OFFSET rip,RIP-ARGOFFSET |
| /* CFI_REL_OFFSET cs,CS-ARGOFFSET*/ |
| /* CFI_REL_OFFSET rflags,EFLAGS-ARGOFFSET*/ |
| CFI_REL_OFFSET rsp,RSP-ARGOFFSET |
| /* CFI_REL_OFFSET ss,SS-ARGOFFSET*/ |
| SAVE_REST |
| call *%rax |
| RESTORE_REST |
| jmp ia32_sysret /* misbalances the return cache */ |
| CFI_ENDPROC |
| END(ia32_ptregs_common) |
