1 /* libunwind - a platform-independent unwind library 2 Copyright (C) 2010 Konstantin Belousov <kib (at) freebsd.org> 3 4 This file is part of libunwind. 5 6 Permission is hereby granted, free of charge, to any person obtaining 7 a copy of this software and associated documentation files (the 8 "Software"), to deal in the Software without restriction, including 9 without limitation the rights to use, copy, modify, merge, publish, 10 distribute, sublicense, and/or sell copies of the Software, and to 11 permit persons to whom the Software is furnished to do so, subject to 12 the following conditions: 13 14 The above copyright notice and this permission notice shall be 15 included in all copies or substantial portions of the Software. 16 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 20 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 21 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 22 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 23 WITH 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 36 PROTECTED int 37 unw_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. 52 48 8d 7c 24 10 lea SIGF_UC(%rsp),%rdi 53 6a 00 pushq $0 54 48 c7 c0 a1 01 00 00 movq $SYS_sigreturn,%rax 55 0f 05 syscall 56 f4 0: hlt 57 eb 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. 75 49 89 ca mov %rcx,%r10 76 0f 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 90 PROTECTED int 91 unw_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 155 HIDDEN void * 156 x86_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 } 186 187 HIDDEN NORETURN void 188 x86_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