1/* libunwind - a platform-independent unwind library 2 Copyright (C) 2010 Konstantin Belousov <kib@freebsd.org> 3 4This file is part of libunwind. 5 6Permission is hereby granted, free of charge, to any person obtaining 7a copy of this software and associated documentation files (the 8"Software"), to deal in the Software without restriction, including 9without limitation the rights to use, copy, modify, merge, publish, 10distribute, sublicense, and/or sell copies of the Software, and to 11permit persons to whom the Software is furnished to do so, subject to 12the following conditions: 13 14The above copyright notice and this permission notice shall be 15included in all copies or substantial portions of the Software. 16 17THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 20NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 21LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 22OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 23WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ 24 25#ifdef HAVE_CONFIG_H 26#include "config.h" 27#endif 28 29#include <sys/ucontext.h> 30#include <machine/sigframe.h> 31#include <signal.h> 32#include <stddef.h> 33#include "unwind_i.h" 34#include "ucontext_i.h" 35 36PROTECTED int 37unw_is_signal_frame (unw_cursor_t *cursor) 38{ 39 /* XXXKIB */ 40 struct cursor *c = (struct cursor *) cursor; 41 unw_word_t w0, w1, w2, b0, ip; 42 unw_addr_space_t as; 43 unw_accessors_t *a; 44 void *arg; 45 int ret; 46 47 as = c->dwarf.as; 48 a = unw_get_accessors (as); 49 arg = c->dwarf.as_arg; 50 51 /* Check if RIP points at sigreturn sequence. 5248 8d 7c 24 10 lea SIGF_UC(%rsp),%rdi 536a 00 pushq $0 5448 c7 c0 a1 01 00 00 movq $SYS_sigreturn,%rax 550f 05 syscall 56f4 0: hlt 57eb fd jmp 0b 58 */ 59 60 ip = c->dwarf.ip; 61 c->sigcontext_format = X86_64_SCF_NONE; 62 if ((ret = (*a->access_mem) (as, ip, &w0, 0, arg)) < 0 63 || (ret = (*a->access_mem) (as, ip + 8, &w1, 0, arg)) < 0 64 || (ret = (*a->access_mem) (as, ip + 16, &w2, 0, arg)) < 0) 65 return 0; 66 w2 &= 0xffffff; 67 if (w0 == 0x48006a10247c8d48 && 68 w1 == 0x050f000001a1c0c7 && 69 w2 == 0x0000000000fdebf4) 70 { 71 c->sigcontext_format = X86_64_SCF_FREEBSD_SIGFRAME; 72 return (c->sigcontext_format); 73 } 74 /* Check if RIP points at standard syscall sequence. 7549 89 ca mov %rcx,%r10 760f 05 syscall 77 */ 78 if ((ret = (*a->access_mem) (as, ip - 5, &b0, 0, arg)) < 0) 79 return (0); 80 Debug (12, "b0 0x%lx\n", b0); 81 if ((b0 & 0xffffffffffffff) == 0x050fca89490000 || 82 (b0 & 0xffffffffff) == 0x050fca8949) 83 { 84 c->sigcontext_format = X86_64_SCF_FREEBSD_SYSCALL; 85 return (c->sigcontext_format); 86 } 87 return (X86_64_SCF_NONE); 88} 89 90PROTECTED int 91unw_handle_signal_frame (unw_cursor_t *cursor) 92{ 93 struct cursor *c = (struct cursor *) cursor; 94 unw_word_t ucontext; 95 int ret; 96 97 if (c->sigcontext_format == X86_64_SCF_FREEBSD_SIGFRAME) 98 { 99 ucontext = c->dwarf.cfa + offsetof(struct sigframe, sf_uc); 100 c->sigcontext_addr = c->dwarf.cfa; 101 Debug(1, "signal frame, skip over trampoline\n"); 102 103 struct dwarf_loc rsp_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSP, 0); 104 ret = dwarf_get (&c->dwarf, rsp_loc, &c->dwarf.cfa); 105 if (ret < 0) 106 { 107 Debug (2, "returning %d\n", ret); 108 return ret; 109 } 110 111 c->dwarf.loc[RAX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RAX, 0); 112 c->dwarf.loc[RDX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RDX, 0); 113 c->dwarf.loc[RCX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RCX, 0); 114 c->dwarf.loc[RBX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RBX, 0); 115 c->dwarf.loc[RSI] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSI, 0); 116 c->dwarf.loc[RDI] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RDI, 0); 117 c->dwarf.loc[RBP] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RBP, 0); 118 c->dwarf.loc[RSP] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSP, 0); 119 c->dwarf.loc[ R8] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R8, 0); 120 c->dwarf.loc[ R9] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R9, 0); 121 c->dwarf.loc[R10] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R10, 0); 122 c->dwarf.loc[R11] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R11, 0); 123 c->dwarf.loc[R12] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R12, 0); 124 c->dwarf.loc[R13] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R13, 0); 125 c->dwarf.loc[R14] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R14, 0); 126 c->dwarf.loc[R15] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R15, 0); 127 c->dwarf.loc[RIP] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RIP, 0); 128 129 return 0; 130 } 131 else if (c->sigcontext_format == X86_64_SCF_FREEBSD_SYSCALL) 132 { 133 c->dwarf.loc[RCX] = c->dwarf.loc[R10]; 134 /* rsp_loc = DWARF_LOC(c->dwarf.cfa - 8, 0); */ 135 /* rbp_loc = c->dwarf.loc[RBP]; */ 136 c->dwarf.loc[RIP] = DWARF_LOC (c->dwarf.cfa, 0); 137 ret = dwarf_get (&c->dwarf, c->dwarf.loc[RIP], &c->dwarf.ip); 138 Debug (1, "Frame Chain [RIP=0x%Lx] = 0x%Lx\n", 139 (unsigned long long) DWARF_GET_LOC (c->dwarf.loc[RIP]), 140 (unsigned long long) c->dwarf.ip); 141 if (ret < 0) 142 { 143 Debug (2, "returning %d\n", ret); 144 return ret; 145 } 146 c->dwarf.cfa += 8; 147 return 1; 148 } 149 else 150 return -UNW_EBADFRAME; 151 152} 153 154#ifndef UNW_REMOTE_ONLY 155HIDDEN void * 156x86_64_r_uc_addr (ucontext_t *uc, int reg) 157{ 158 /* NOTE: common_init() in init.h inlines these for fast path access. */ 159 void *addr; 160 161 switch (reg) 162 { 163 case UNW_X86_64_R8: addr = &uc->uc_mcontext.mc_r8; break; 164 case UNW_X86_64_R9: addr = &uc->uc_mcontext.mc_r9; break; 165 case UNW_X86_64_R10: addr = &uc->uc_mcontext.mc_r10; break; 166 case UNW_X86_64_R11: addr = &uc->uc_mcontext.mc_r11; break; 167 case UNW_X86_64_R12: addr = &uc->uc_mcontext.mc_r12; break; 168 case UNW_X86_64_R13: addr = &uc->uc_mcontext.mc_r13; break; 169 case UNW_X86_64_R14: addr = &uc->uc_mcontext.mc_r14; break; 170 case UNW_X86_64_R15: addr = &uc->uc_mcontext.mc_r15; break; 171 case UNW_X86_64_RDI: addr = &uc->uc_mcontext.mc_rdi; break; 172 case UNW_X86_64_RSI: addr = &uc->uc_mcontext.mc_rsi; break; 173 case UNW_X86_64_RBP: addr = &uc->uc_mcontext.mc_rbp; break; 174 case UNW_X86_64_RBX: addr = &uc->uc_mcontext.mc_rbx; break; 175 case UNW_X86_64_RDX: addr = &uc->uc_mcontext.mc_rdx; break; 176 case UNW_X86_64_RAX: addr = &uc->uc_mcontext.mc_rax; break; 177 case UNW_X86_64_RCX: addr = &uc->uc_mcontext.mc_rcx; break; 178 case UNW_X86_64_RSP: addr = &uc->uc_mcontext.mc_rsp; break; 179 case UNW_X86_64_RIP: addr = &uc->uc_mcontext.mc_rip; break; 180 181 default: 182 addr = NULL; 183 } 184 return addr; 185} 186 187HIDDEN NORETURN void 188x86_64_sigreturn (unw_cursor_t *cursor) 189{ 190 struct cursor *c = (struct cursor *) cursor; 191 ucontext_t *uc = (ucontext_t *)(c->sigcontext_addr + 192 offsetof(struct sigframe, sf_uc)); 193 194 Debug (8, "resuming at ip=%llx via sigreturn(%p)\n", 195 (unsigned long long) c->dwarf.ip, uc); 196 sigreturn(uc); 197 abort(); 198} 199#endif 200