/* libunwind - a platform-independent unwind library Copyright (C) 2010 Konstantin Belousov <kib@freebsd.org> This file is part of libunwind. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include <sys/ucontext.h> #include <machine/sigframe.h> #include <signal.h> #include <stddef.h> #include "unwind_i.h" #include "ucontext_i.h" PROTECTED int unw_is_signal_frame (unw_cursor_t *cursor) { /* XXXKIB */ struct cursor *c = (struct cursor *) cursor; unw_word_t w0, w1, w2, b0, ip; unw_addr_space_t as; unw_accessors_t *a; void *arg; int ret; as = c->dwarf.as; a = unw_get_accessors (as); arg = c->dwarf.as_arg; /* Check if RIP points at sigreturn sequence. 48 8d 7c 24 10 lea SIGF_UC(%rsp),%rdi 6a 00 pushq $0 48 c7 c0 a1 01 00 00 movq $SYS_sigreturn,%rax 0f 05 syscall f4 0: hlt eb fd jmp 0b */ ip = c->dwarf.ip; c->sigcontext_format = X86_64_SCF_NONE; if ((ret = (*a->access_mem) (as, ip, &w0, 0, arg)) < 0 || (ret = (*a->access_mem) (as, ip + 8, &w1, 0, arg)) < 0 || (ret = (*a->access_mem) (as, ip + 16, &w2, 0, arg)) < 0) return 0; w2 &= 0xffffff; if (w0 == 0x48006a10247c8d48 && w1 == 0x050f000001a1c0c7 && w2 == 0x0000000000fdebf4) { c->sigcontext_format = X86_64_SCF_FREEBSD_SIGFRAME; return (c->sigcontext_format); } /* Check if RIP points at standard syscall sequence. 49 89 ca mov %rcx,%r10 0f 05 syscall */ if ((ret = (*a->access_mem) (as, ip - 5, &b0, 0, arg)) < 0) return (0); Debug (12, "b0 0x%lx\n", b0); if ((b0 & 0xffffffffffffff) == 0x050fca89490000 || (b0 & 0xffffffffff) == 0x050fca8949) { c->sigcontext_format = X86_64_SCF_FREEBSD_SYSCALL; return (c->sigcontext_format); } return (X86_64_SCF_NONE); } PROTECTED int unw_handle_signal_frame (unw_cursor_t *cursor) { struct cursor *c = (struct cursor *) cursor; unw_word_t ucontext; int ret; if (c->sigcontext_format == X86_64_SCF_FREEBSD_SIGFRAME) { ucontext = c->dwarf.cfa + offsetof(struct sigframe, sf_uc); c->sigcontext_addr = c->dwarf.cfa; Debug(1, "signal frame, skip over trampoline\n"); struct dwarf_loc rsp_loc = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSP, 0); ret = dwarf_get (&c->dwarf, rsp_loc, &c->dwarf.cfa); if (ret < 0) { Debug (2, "returning %d\n", ret); return ret; } c->dwarf.loc[RAX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RAX, 0); c->dwarf.loc[RDX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RDX, 0); c->dwarf.loc[RCX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RCX, 0); c->dwarf.loc[RBX] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RBX, 0); c->dwarf.loc[RSI] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSI, 0); c->dwarf.loc[RDI] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RDI, 0); c->dwarf.loc[RBP] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RBP, 0); c->dwarf.loc[RSP] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RSP, 0); c->dwarf.loc[ R8] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R8, 0); c->dwarf.loc[ R9] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R9, 0); c->dwarf.loc[R10] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R10, 0); c->dwarf.loc[R11] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R11, 0); c->dwarf.loc[R12] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R12, 0); c->dwarf.loc[R13] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R13, 0); c->dwarf.loc[R14] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R14, 0); c->dwarf.loc[R15] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_R15, 0); c->dwarf.loc[RIP] = DWARF_LOC (ucontext + UC_MCONTEXT_GREGS_RIP, 0); return 0; } else if (c->sigcontext_format == X86_64_SCF_FREEBSD_SYSCALL) { c->dwarf.loc[RCX] = c->dwarf.loc[R10]; /* rsp_loc = DWARF_LOC(c->dwarf.cfa - 8, 0); */ /* rbp_loc = c->dwarf.loc[RBP]; */ c->dwarf.loc[RIP] = DWARF_LOC (c->dwarf.cfa, 0); ret = dwarf_get (&c->dwarf, c->dwarf.loc[RIP], &c->dwarf.ip); Debug (1, "Frame Chain [RIP=0x%Lx] = 0x%Lx\n", (unsigned long long) DWARF_GET_LOC (c->dwarf.loc[RIP]), (unsigned long long) c->dwarf.ip); if (ret < 0) { Debug (2, "returning %d\n", ret); return ret; } c->dwarf.cfa += 8; return 1; } else return -UNW_EBADFRAME; } #ifndef UNW_REMOTE_ONLY HIDDEN void * x86_64_r_uc_addr (ucontext_t *uc, int reg) { /* NOTE: common_init() in init.h inlines these for fast path access. */ void *addr; switch (reg) { case UNW_X86_64_R8: addr = &uc->uc_mcontext.mc_r8; break; case UNW_X86_64_R9: addr = &uc->uc_mcontext.mc_r9; break; case UNW_X86_64_R10: addr = &uc->uc_mcontext.mc_r10; break; case UNW_X86_64_R11: addr = &uc->uc_mcontext.mc_r11; break; case UNW_X86_64_R12: addr = &uc->uc_mcontext.mc_r12; break; case UNW_X86_64_R13: addr = &uc->uc_mcontext.mc_r13; break; case UNW_X86_64_R14: addr = &uc->uc_mcontext.mc_r14; break; case UNW_X86_64_R15: addr = &uc->uc_mcontext.mc_r15; break; case UNW_X86_64_RDI: addr = &uc->uc_mcontext.mc_rdi; break; case UNW_X86_64_RSI: addr = &uc->uc_mcontext.mc_rsi; break; case UNW_X86_64_RBP: addr = &uc->uc_mcontext.mc_rbp; break; case UNW_X86_64_RBX: addr = &uc->uc_mcontext.mc_rbx; break; case UNW_X86_64_RDX: addr = &uc->uc_mcontext.mc_rdx; break; case UNW_X86_64_RAX: addr = &uc->uc_mcontext.mc_rax; break; case UNW_X86_64_RCX: addr = &uc->uc_mcontext.mc_rcx; break; case UNW_X86_64_RSP: addr = &uc->uc_mcontext.mc_rsp; break; case UNW_X86_64_RIP: addr = &uc->uc_mcontext.mc_rip; break; default: addr = NULL; } return addr; } HIDDEN NORETURN void x86_64_sigreturn (unw_cursor_t *cursor) { struct cursor *c = (struct cursor *) cursor; ucontext_t *uc = (ucontext_t *)(c->sigcontext_addr + offsetof(struct sigframe, sf_uc)); Debug (8, "resuming at ip=%llx via sigreturn(%p)\n", (unsigned long long) c->dwarf.ip, uc); sigreturn(uc); abort(); } #endif