/*- * Copyright (c) 2003 Peter Wemm * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: release/9.1.0/sys/amd64/ia32/ia32_sigtramp.S 223254 2011-06-18 12:13:28Z kib $ */ #include "opt_compat.h" #include #include #include "ia32_assym.h" .text .code32 /* * Signal trampoline, copied to top of user stack * XXX may need to be MD to match backend sendsig handoff protocol */ ALIGN_TEXT .globl ia32_sigcode ia32_sigcode: calll *IA32_SIGF_HANDLER(%esp) leal IA32_SIGF_UC(%esp),%eax /* get ucontext */ pushl %eax movl $SYS_sigreturn,%eax pushl %eax /* junk to fake return addr. */ int $0x80 /* enter kernel with args */ /* on stack */ 1: jmp 1b #ifdef COMPAT_FREEBSD4 ALIGN_TEXT freebsd4_ia32_sigcode: calll *IA32_SIGF_HANDLER(%esp) leal IA32_SIGF_UC4(%esp),%eax/* get ucontext */ pushl %eax movl $344,%eax /* 4.x SYS_sigreturn */ pushl %eax /* junk to fake return addr. */ int $0x80 /* enter kernel with args */ /* on stack */ 1: jmp 1b #endif #ifdef COMPAT_43 ALIGN_TEXT ia32_osigcode: calll *IA32_SIGF_HANDLER(%esp)/* call signal handler */ leal IA32_SIGF_SC(%esp),%eax /* get sigcontext */ pushl %eax movl $103,%eax /* 3.x SYS_sigreturn */ pushl %eax /* junk to fake return addr. */ int $0x80 /* enter kernel with args */ 1: jmp 1b /* * The lcall $7,$0 emulator cannot use the call gate that does an * inter-privilege transition. The reason is that the call gate * does not disable interrupts, and, before the swapgs is * executed, we would have a window where the ring 0 code is * executed with the wrong gsbase. * * Instead, reflect the lcall $7,$0 back to ring 3 trampoline * which sets up the frame for int $0x80. */ ALIGN_TEXT lcall_tramp: cmpl $SYS_vfork,%eax je 2f pushl %ebp movl %esp,%ebp pushl 0x24(%ebp) /* arg 6 */ pushl 0x20(%ebp) pushl 0x1c(%ebp) pushl 0x18(%ebp) pushl 0x14(%ebp) pushl 0x10(%ebp) /* arg 1 */ pushl 0xc(%ebp) /* gap */ int $0x80 leavel 1: lretl 2: /* * vfork handling is special and relies on the libc stub saving * the return ip in %ecx. If vfork failed, then there is no * child which can corrupt the frame created by call gate. */ int $0x80 jb 1b addl $8,%esp jmpl *%ecx #endif ALIGN_TEXT esigcode: .data .globl sz_ia32_sigcode sz_ia32_sigcode: .long esigcode-ia32_sigcode #ifdef COMPAT_FREEBSD4 .globl sz_freebsd4_ia32_sigcode sz_freebsd4_ia32_sigcode: .long esigcode-freebsd4_ia32_sigcode #endif #ifdef COMPAT_43 .globl sz_ia32_osigcode sz_ia32_osigcode: .long esigcode-ia32_osigcode .globl sz_lcall_tramp sz_lcall_tramp: .long esigcode-lcall_tramp #endif