/*- * Copyright (c) 2004 Tim J. Robbins * Copyright (c) 2003 Peter Wemm * Copyright (c) 2002 Doug Rabson * Copyright (c) 1998-1999 Andrew Gallatin * Copyright (c) 1994-1996 Søren Schmidt * All rights reserved. * Copyright (c) 2013, 2021 Dmitry Chagin * * 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 * in this position and unchanged. * 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. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. */ #include #define __ELF_WORD_SIZE 64 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include _Static_assert(sizeof(struct l_fpstate) == sizeof(__typeof(((mcontext_t *)0)->mc_fpstate)), "fxsave area size incorrect"); MODULE_VERSION(linux64, 1); #define LINUX_VDSOPAGE_SIZE PAGE_SIZE * 2 #define LINUX_VDSOPAGE_LA48 (VM_MAXUSER_ADDRESS_LA48 - \ LINUX_VDSOPAGE_SIZE) #define LINUX_SHAREDPAGE_LA48 (LINUX_VDSOPAGE_LA48 - PAGE_SIZE) /* * PAGE_SIZE - the size * of the native SHAREDPAGE */ #define LINUX_USRSTACK_LA48 LINUX_SHAREDPAGE_LA48 #define LINUX_PS_STRINGS_LA48 (LINUX_USRSTACK_LA48 - \ sizeof(struct ps_strings)) static int linux_szsigcode; static vm_object_t linux_vdso_obj; static char *linux_vdso_mapping; extern char _binary_linux_vdso_so_o_start; extern char _binary_linux_vdso_so_o_end; static vm_offset_t linux_vdso_base; extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; extern const char *linux_syscallnames[]; SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); static void linux_vdso_install(const void *param); static void linux_vdso_deinstall(const void *param); static void linux_vdso_reloc(char *mapping, Elf_Addr offset); static void linux_set_syscall_retval(struct thread *td, int error); static int linux_fetch_syscall_args(struct thread *td); static void linux_exec_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack); static void linux_exec_sysvec_init(void *param); static int linux_on_exec_vmspace(struct proc *p, struct image_params *imgp); static void linux_set_fork_retval(struct thread *td); static int linux_vsyscall(struct thread *td); LINUX_VDSO_SYM_INTPTR(linux_rt_sigcode); LINUX_VDSO_SYM_CHAR(linux_platform); LINUX_VDSO_SYM_INTPTR(kern_timekeep_base); LINUX_VDSO_SYM_INTPTR(kern_tsc_selector); LINUX_VDSO_SYM_INTPTR(kern_cpu_selector); /* * According to the Intel x86 ISA 64-bit syscall * saves %rip to %rcx and rflags to %r11. Registers on syscall entry: * %rax system call number * %rcx return address * %r11 saved rflags * %rdi arg1 * %rsi arg2 * %rdx arg3 * %r10 arg4 * %r8 arg5 * %r9 arg6 * * Then FreeBSD fast_syscall() move registers: * %rcx -> trapframe.tf_rip * %r10 -> trapframe.tf_rcx */ static int linux_fetch_syscall_args(struct thread *td) { struct proc *p; struct trapframe *frame; struct syscall_args *sa; p = td->td_proc; frame = td->td_frame; sa = &td->td_sa; sa->args[0] = frame->tf_rdi; sa->args[1] = frame->tf_rsi; sa->args[2] = frame->tf_rdx; sa->args[3] = frame->tf_rcx; sa->args[4] = frame->tf_r8; sa->args[5] = frame->tf_r9; sa->code = frame->tf_rax; if (sa->code >= p->p_sysent->sv_size) /* nosys */ sa->callp = &nosys_sysent; else sa->callp = &p->p_sysent->sv_table[sa->code]; /* Restore r10 earlier to avoid doing this multiply times. */ frame->tf_r10 = frame->tf_rcx; /* Restore %rcx for machine context. */ frame->tf_rcx = frame->tf_rip; td->td_retval[0] = 0; return (0); } static void linux_set_syscall_retval(struct thread *td, int error) { struct trapframe *frame; frame = td->td_frame; switch (error) { case 0: frame->tf_rax = td->td_retval[0]; break; case ERESTART: /* * Reconstruct pc, we know that 'syscall' is 2 bytes, * lcall $X,y is 7 bytes, int 0x80 is 2 bytes. * We saved this in tf_err. * */ frame->tf_rip -= frame->tf_err; break; case EJUSTRETURN: break; default: frame->tf_rax = bsd_to_linux_errno(error); break; } /* * Differently from FreeBSD native ABI, on Linux only %rcx * and %r11 values are not preserved across the syscall. * Require full context restore to get all registers except * those two restored at return to usermode. */ set_pcb_flags(td->td_pcb, PCB_FULL_IRET); } static void linux_set_fork_retval(struct thread *td) { struct trapframe *frame = td->td_frame; frame->tf_rax = 0; } void linux64_arch_copyout_auxargs(struct image_params *imgp, Elf_Auxinfo **pos) { AUXARGS_ENTRY((*pos), LINUX_AT_SYSINFO_EHDR, linux_vdso_base); AUXARGS_ENTRY((*pos), LINUX_AT_HWCAP, cpu_feature); AUXARGS_ENTRY((*pos), LINUX_AT_HWCAP2, linux_x86_elf_hwcap2()); AUXARGS_ENTRY((*pos), LINUX_AT_PLATFORM, PTROUT(linux_platform)); } /* * Reset registers to default values on exec. */ static void linux_exec_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack) { struct trapframe *regs; struct pcb *pcb; register_t saved_rflags; regs = td->td_frame; pcb = td->td_pcb; if (td->td_proc->p_md.md_ldt != NULL) user_ldt_free(td); pcb->pcb_fsbase = 0; pcb->pcb_gsbase = 0; clear_pcb_flags(pcb, PCB_32BIT); pcb->pcb_initial_fpucw = __LINUX_NPXCW__; set_pcb_flags(pcb, PCB_FULL_IRET); saved_rflags = regs->tf_rflags & PSL_T; bzero((char *)regs, sizeof(struct trapframe)); regs->tf_rip = imgp->entry_addr; regs->tf_rsp = stack; regs->tf_rflags = PSL_USER | saved_rflags; regs->tf_ss = _udatasel; regs->tf_cs = _ucodesel; regs->tf_ds = _udatasel; regs->tf_es = _udatasel; regs->tf_fs = _ufssel; regs->tf_gs = _ugssel; regs->tf_flags = TF_HASSEGS; x86_clear_dbregs(pcb); /* * Drop the FP state if we hold it, so that the process gets a * clean FP state if it uses the FPU again. */ fpstate_drop(td); } static int linux_fxrstor(struct thread *td, mcontext_t *mcp, struct l_sigcontext *sc) { struct savefpu *fp = (struct savefpu *)&mcp->mc_fpstate[0]; int error; error = copyin(PTRIN(sc->sc_fpstate), fp, sizeof(mcp->mc_fpstate)); if (error != 0) return (error); bzero(&fp->sv_pad[0], sizeof(fp->sv_pad)); return (set_fpcontext(td, mcp, NULL, 0)); } static int linux_xrstor(struct thread *td, mcontext_t *mcp, struct l_sigcontext *sc) { struct savefpu *fp = (struct savefpu *)&mcp->mc_fpstate[0]; char *xfpustate; struct proc *p; uint32_t magic2; int error; p = td->td_proc; mcp->mc_xfpustate_len = cpu_max_ext_state_size - sizeof(struct savefpu); /* Legacy region of an xsave area. */ error = copyin(PTRIN(sc->sc_fpstate), fp, sizeof(mcp->mc_fpstate)); if (error != 0) return (error); bzero(&fp->sv_pad[0], sizeof(fp->sv_pad)); /* Extended region of an xsave area. */ sc->sc_fpstate += sizeof(mcp->mc_fpstate); xfpustate = (char *)fpu_save_area_alloc(); error = copyin(PTRIN(sc->sc_fpstate), xfpustate, mcp->mc_xfpustate_len); if (error != 0) { fpu_save_area_free((struct savefpu *)xfpustate); uprintf("pid %d (%s): linux xrstor failed\n", p->p_pid, td->td_name); return (error); } /* Linux specific end of xsave area marker. */ sc->sc_fpstate += mcp->mc_xfpustate_len; error = copyin(PTRIN(sc->sc_fpstate), &magic2, LINUX_FP_XSTATE_MAGIC2_SIZE); if (error != 0 || magic2 != LINUX_FP_XSTATE_MAGIC2) { fpu_save_area_free((struct savefpu *)xfpustate); uprintf("pid %d (%s): sigreturn magic2 0x%x error %d\n", p->p_pid, td->td_name, magic2, error); return (error); } error = set_fpcontext(td, mcp, xfpustate, mcp->mc_xfpustate_len); fpu_save_area_free((struct savefpu *)xfpustate); if (error != 0) { uprintf("pid %d (%s): sigreturn set_fpcontext error %d\n", p->p_pid, td->td_name, error); } return (error); } static int linux_copyin_fpstate(struct thread *td, struct l_ucontext *uc) { mcontext_t mc; bzero(&mc, sizeof(mc)); mc.mc_ownedfp = _MC_FPOWNED_FPU; mc.mc_fpformat = _MC_FPFMT_XMM; if ((uc->uc_flags & LINUX_UC_FP_XSTATE) != 0) return (linux_xrstor(td, &mc, &uc->uc_mcontext)); else return (linux_fxrstor(td, &mc, &uc->uc_mcontext)); } /* * Copied from amd64/amd64/machdep.c */ int linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) { struct proc *p; struct l_rt_sigframe sf; struct l_sigcontext *context; struct trapframe *regs; unsigned long rflags; sigset_t bmask; int error; ksiginfo_t ksi; regs = td->td_frame; error = copyin((void *)regs->tf_rbx, &sf, sizeof(sf)); if (error != 0) return (error); p = td->td_proc; context = &sf.sf_uc.uc_mcontext; rflags = context->sc_rflags; /* * Don't allow users to change privileged or reserved flags. */ /* * XXX do allow users to change the privileged flag PSL_RF. * The cpu sets PSL_RF in tf_rflags for faults. Debuggers * should sometimes set it there too. tf_rflags is kept in * the signal context during signal handling and there is no * other place to remember it, so the PSL_RF bit may be * corrupted by the signal handler without us knowing. * Corruption of the PSL_RF bit at worst causes one more or * one less debugger trap, so allowing it is fairly harmless. */ if (!EFL_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) { uprintf("pid %d comm %s linux mangled rflags %#lx\n", p->p_pid, p->p_comm, rflags); return (EINVAL); } /* * Don't allow users to load a valid privileged %cs. Let the * hardware check for invalid selectors, excess privilege in * other selectors, invalid %eip's and invalid %esp's. */ if (!CS_SECURE(context->sc_cs)) { uprintf("pid %d comm %s linux mangled cs %#x\n", p->p_pid, p->p_comm, context->sc_cs); ksiginfo_init_trap(&ksi); ksi.ksi_signo = SIGBUS; ksi.ksi_code = BUS_OBJERR; ksi.ksi_trapno = T_PROTFLT; ksi.ksi_addr = (void *)regs->tf_rip; trapsignal(td, &ksi); return (EINVAL); } linux_to_bsd_sigset(&sf.sf_uc.uc_sigmask, &bmask); kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0); regs->tf_rdi = context->sc_rdi; regs->tf_rsi = context->sc_rsi; regs->tf_rdx = context->sc_rdx; regs->tf_rbp = context->sc_rbp; regs->tf_rbx = context->sc_rbx; regs->tf_rcx = context->sc_rcx; regs->tf_rax = context->sc_rax; regs->tf_rip = context->sc_rip; regs->tf_rsp = context->sc_rsp; regs->tf_r8 = context->sc_r8; regs->tf_r9 = context->sc_r9; regs->tf_r10 = context->sc_r10; regs->tf_r11 = context->sc_r11; regs->tf_r12 = context->sc_r12; regs->tf_r13 = context->sc_r13; regs->tf_r14 = context->sc_r14; regs->tf_r15 = context->sc_r15; regs->tf_cs = context->sc_cs; regs->tf_err = context->sc_err; regs->tf_rflags = rflags; error = linux_copyin_fpstate(td, &sf.sf_uc); if (error != 0) { uprintf("pid %d comm %s linux can't restore fpu state %d\n", p->p_pid, p->p_comm, error); return (error); } set_pcb_flags(td->td_pcb, PCB_FULL_IRET); return (EJUSTRETURN); } static int linux_fxsave(mcontext_t *mcp, void *ufp) { struct l_fpstate *fx = (struct l_fpstate *)&mcp->mc_fpstate[0]; bzero(&fx->reserved2[0], sizeof(fx->reserved2)); return (copyout(fx, ufp, sizeof(*fx))); } static int linux_xsave(mcontext_t *mcp, char *xfpusave, char *ufp) { struct l_fpstate *fx = (struct l_fpstate *)&mcp->mc_fpstate[0]; uint32_t magic2; int error; /* Legacy region of an xsave area. */ fx->sw_reserved.magic1 = LINUX_FP_XSTATE_MAGIC1; fx->sw_reserved.xstate_size = mcp->mc_xfpustate_len + sizeof(*fx); fx->sw_reserved.extended_size = fx->sw_reserved.xstate_size + LINUX_FP_XSTATE_MAGIC2_SIZE; fx->sw_reserved.xfeatures = xsave_mask; error = copyout(fx, ufp, sizeof(*fx)); if (error != 0) return (error); ufp += sizeof(*fx); /* Extended region of an xsave area. */ error = copyout(xfpusave, ufp, mcp->mc_xfpustate_len); if (error != 0) return (error); /* Linux specific end of xsave area marker. */ ufp += mcp->mc_xfpustate_len; magic2 = LINUX_FP_XSTATE_MAGIC2; return (copyout(&magic2, ufp, LINUX_FP_XSTATE_MAGIC2_SIZE)); } static int linux_copyout_fpstate(struct thread *td, struct l_ucontext *uc, char **sp) { size_t xfpusave_len; char *xfpusave; mcontext_t mc; char *ufp = *sp; get_fpcontext(td, &mc, &xfpusave, &xfpusave_len); KASSERT(mc.mc_fpformat != _MC_FPFMT_NODEV, ("fpu not present")); /* Room for fxsave area. */ ufp -= sizeof(struct l_fpstate); if (xfpusave != NULL) { /* Room for xsave area. */ ufp -= (xfpusave_len + LINUX_FP_XSTATE_MAGIC2_SIZE); uc->uc_flags |= LINUX_UC_FP_XSTATE; } *sp = ufp = (char *)((unsigned long)ufp & ~0x3Ful); if (xfpusave != NULL) return (linux_xsave(&mc, xfpusave, ufp)); else return (linux_fxsave(&mc, ufp)); } /* * copied from amd64/amd64/machdep.c * * Send an interrupt to process. */ static void linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) { struct l_rt_sigframe sf, *sfp; struct proc *p; struct thread *td; struct sigacts *psp; char *sp; struct trapframe *regs; int sig, code; int oonstack, issiginfo; td = curthread; p = td->td_proc; PROC_LOCK_ASSERT(p, MA_OWNED); sig = linux_translate_traps(ksi->ksi_signo, ksi->ksi_trapno); psp = p->p_sigacts; issiginfo = SIGISMEMBER(psp->ps_siginfo, sig); code = ksi->ksi_code; mtx_assert(&psp->ps_mtx, MA_OWNED); regs = td->td_frame; oonstack = sigonstack(regs->tf_rsp); LINUX_CTR4(rt_sendsig, "%p, %d, %p, %u", catcher, sig, mask, code); bzero(&sf, sizeof(sf)); sf.sf_uc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); sf.sf_uc.uc_stack.ss_size = td->td_sigstk.ss_size; sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; /* Allocate space for the signal handler context. */ if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && SIGISMEMBER(psp->ps_sigonstack, sig)) { sp = (char *)td->td_sigstk.ss_sp + td->td_sigstk.ss_size; } else sp = (char *)regs->tf_rsp - 128; mtx_unlock(&psp->ps_mtx); PROC_UNLOCK(p); if (linux_copyout_fpstate(td, &sf.sf_uc, &sp) != 0) { uprintf("pid %d comm %s linux can't save fpu state, killing\n", p->p_pid, p->p_comm); PROC_LOCK(p); sigexit(td, SIGILL); } sf.sf_uc.uc_mcontext.sc_fpstate = (register_t)sp; /* Make room, keeping the stack aligned. */ sp -= sizeof(struct l_rt_sigframe); sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul); /* Save user context. */ bsd_to_linux_sigset(mask, &sf.sf_uc.uc_sigmask); sf.sf_uc.uc_mcontext.sc_mask = sf.sf_uc.uc_sigmask; sf.sf_uc.uc_mcontext.sc_rdi = regs->tf_rdi; sf.sf_uc.uc_mcontext.sc_rsi = regs->tf_rsi; sf.sf_uc.uc_mcontext.sc_rdx = regs->tf_rdx; sf.sf_uc.uc_mcontext.sc_rbp = regs->tf_rbp; sf.sf_uc.uc_mcontext.sc_rbx = regs->tf_rbx; sf.sf_uc.uc_mcontext.sc_rcx = regs->tf_rcx; sf.sf_uc.uc_mcontext.sc_rax = regs->tf_rax; sf.sf_uc.uc_mcontext.sc_rip = regs->tf_rip; sf.sf_uc.uc_mcontext.sc_rsp = regs->tf_rsp; sf.sf_uc.uc_mcontext.sc_r8 = regs->tf_r8; sf.sf_uc.uc_mcontext.sc_r9 = regs->tf_r9; sf.sf_uc.uc_mcontext.sc_r10 = regs->tf_r10; sf.sf_uc.uc_mcontext.sc_r11 = regs->tf_r11; sf.sf_uc.uc_mcontext.sc_r12 = regs->tf_r12; sf.sf_uc.uc_mcontext.sc_r13 = regs->tf_r13; sf.sf_uc.uc_mcontext.sc_r14 = regs->tf_r14; sf.sf_uc.uc_mcontext.sc_r15 = regs->tf_r15; sf.sf_uc.uc_mcontext.sc_cs = regs->tf_cs; sf.sf_uc.uc_mcontext.sc_rflags = regs->tf_rflags; sf.sf_uc.uc_mcontext.sc_err = regs->tf_err; sf.sf_uc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); sf.sf_uc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr; /* Translate the signal. */ sig = bsd_to_linux_signal(sig); /* Fill in POSIX parts. */ siginfo_to_lsiginfo(&ksi->ksi_info, &sf.sf_si, sig); /* Copy the sigframe out to the user's stack. */ if (copyout(&sf, sfp, sizeof(*sfp)) != 0) { uprintf("pid %d comm %s has trashed its stack, killing\n", p->p_pid, p->p_comm); PROC_LOCK(p); sigexit(td, SIGILL); } fpstate_drop(td); /* Build the argument list for the signal handler. */ regs->tf_rdi = sig; /* arg 1 in %rdi */ regs->tf_rax = 0; if (issiginfo) { regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */ regs->tf_rdx = (register_t)&sfp->sf_uc; /* arg 3 in %rdx */ } else { regs->tf_rsi = 0; regs->tf_rdx = 0; } regs->tf_rcx = (register_t)catcher; regs->tf_rsp = (long)sfp; regs->tf_rip = linux_rt_sigcode; regs->tf_rflags &= ~(PSL_T | PSL_D); regs->tf_cs = _ucodesel; set_pcb_flags(td->td_pcb, PCB_FULL_IRET); PROC_LOCK(p); mtx_lock(&psp->ps_mtx); } #define LINUX_VSYSCALL_START (-10UL << 20) #define LINUX_VSYSCALL_SZ 1024 const unsigned long linux_vsyscall_vector[] = { LINUX_SYS_gettimeofday, LINUX_SYS_linux_time, LINUX_SYS_linux_getcpu, }; static int linux_vsyscall(struct thread *td) { struct trapframe *frame; uint64_t retqaddr; int code, traced; int error; frame = td->td_frame; /* Check %rip for vsyscall area. */ if (__predict_true(frame->tf_rip < LINUX_VSYSCALL_START)) return (EINVAL); if ((frame->tf_rip & (LINUX_VSYSCALL_SZ - 1)) != 0) return (EINVAL); code = (frame->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SZ; if (code >= nitems(linux_vsyscall_vector)) return (EINVAL); /* * vsyscall called as callq *(%rax), so we must * use return address from %rsp and also fixup %rsp. */ error = copyin((void *)frame->tf_rsp, &retqaddr, sizeof(retqaddr)); if (error) return (error); frame->tf_rip = retqaddr; frame->tf_rax = linux_vsyscall_vector[code]; frame->tf_rsp += 8; traced = (frame->tf_flags & PSL_T); amd64_syscall(td, traced); return (0); } struct sysentvec elf_linux_sysvec = { .sv_size = LINUX_SYS_MAXSYSCALL, .sv_table = linux_sysent, .sv_fixup = __elfN(freebsd_fixup), .sv_sendsig = linux_rt_sendsig, .sv_sigcode = &_binary_linux_vdso_so_o_start, .sv_szsigcode = &linux_szsigcode, .sv_name = "Linux ELF64", .sv_coredump = elf64_coredump, .sv_elf_core_osabi = ELFOSABI_NONE, .sv_elf_core_abi_vendor = LINUX_ABI_VENDOR, .sv_elf_core_prepare_notes = linux64_prepare_notes, .sv_imgact_try = linux_exec_imgact_try, .sv_minsigstksz = LINUX_MINSIGSTKSZ, .sv_minuser = VM_MIN_ADDRESS, .sv_maxuser = VM_MAXUSER_ADDRESS_LA48, .sv_usrstack = LINUX_USRSTACK_LA48, .sv_psstrings = LINUX_PS_STRINGS_LA48, .sv_psstringssz = sizeof(struct ps_strings), .sv_stackprot = VM_PROT_ALL, .sv_copyout_auxargs = __linuxN(copyout_auxargs), .sv_copyout_strings = __linuxN(copyout_strings), .sv_setregs = linux_exec_setregs, .sv_fixlimit = NULL, .sv_maxssiz = NULL, .sv_flags = SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN | SV_SIG_WAITNDQ | SV_TIMEKEEP, .sv_set_syscall_retval = linux_set_syscall_retval, .sv_fetch_syscall_args = linux_fetch_syscall_args, .sv_syscallnames = linux_syscallnames, .sv_shared_page_base = LINUX_SHAREDPAGE_LA48, .sv_shared_page_len = PAGE_SIZE, .sv_schedtail = linux_schedtail, .sv_thread_detach = linux_thread_detach, .sv_trap = linux_vsyscall, .sv_hwcap = NULL, .sv_hwcap2 = NULL, .sv_onexec = linux_on_exec_vmspace, .sv_onexit = linux_on_exit, .sv_ontdexit = linux_thread_dtor, .sv_setid_allowed = &linux_setid_allowed_query, .sv_set_fork_retval = linux_set_fork_retval, }; static int linux_on_exec_vmspace(struct proc *p, struct image_params *imgp) { int error; error = linux_map_vdso(p, linux_vdso_obj, linux_vdso_base, LINUX_VDSOPAGE_SIZE, imgp); if (error == 0) linux_on_exec(p, imgp); return (error); } /* * linux_vdso_install() and linux_exec_sysvec_init() must be called * after exec_sysvec_init() which is SI_SUB_EXEC (SI_ORDER_ANY). */ static void linux_exec_sysvec_init(void *param) { l_uintptr_t *ktimekeep_base, *ktsc_selector; struct sysentvec *sv; ptrdiff_t tkoff; sv = param; amd64_lower_shared_page(sv); /* Fill timekeep_base */ exec_sysvec_init(sv); tkoff = kern_timekeep_base - linux_vdso_base; ktimekeep_base = (l_uintptr_t *)(linux_vdso_mapping + tkoff); *ktimekeep_base = sv->sv_timekeep_base; tkoff = kern_tsc_selector - linux_vdso_base; ktsc_selector = (l_uintptr_t *)(linux_vdso_mapping + tkoff); *ktsc_selector = linux_vdso_tsc_selector_idx(); if (bootverbose) printf("Linux x86-64 vDSO tsc_selector: %lu\n", *ktsc_selector); tkoff = kern_cpu_selector - linux_vdso_base; ktsc_selector = (l_uintptr_t *)(linux_vdso_mapping + tkoff); *ktsc_selector = linux_vdso_cpu_selector_idx(); if (bootverbose) printf("Linux x86-64 vDSO cpu_selector: %lu\n", *ktsc_selector); } SYSINIT(elf_linux_exec_sysvec_init, SI_SUB_EXEC + 1, SI_ORDER_ANY, linux_exec_sysvec_init, &elf_linux_sysvec); static void linux_vdso_install(const void *param) { char *vdso_start = &_binary_linux_vdso_so_o_start; char *vdso_end = &_binary_linux_vdso_so_o_end; linux_szsigcode = vdso_end - vdso_start; MPASS(linux_szsigcode <= LINUX_VDSOPAGE_SIZE); linux_vdso_base = LINUX_VDSOPAGE_LA48; if (hw_lower_amd64_sharedpage != 0) linux_vdso_base -= PAGE_SIZE; __elfN(linux_vdso_fixup)(vdso_start, linux_vdso_base); linux_vdso_obj = __elfN(linux_shared_page_init) (&linux_vdso_mapping, LINUX_VDSOPAGE_SIZE); bcopy(vdso_start, linux_vdso_mapping, linux_szsigcode); linux_vdso_reloc(linux_vdso_mapping, linux_vdso_base); } SYSINIT(elf_linux_vdso_init, SI_SUB_EXEC + 1, SI_ORDER_FIRST, linux_vdso_install, NULL); static void linux_vdso_deinstall(const void *param) { __elfN(linux_shared_page_fini)(linux_vdso_obj, linux_vdso_mapping, LINUX_VDSOPAGE_SIZE); } SYSUNINIT(elf_linux_vdso_uninit, SI_SUB_EXEC, SI_ORDER_FIRST, linux_vdso_deinstall, NULL); static void linux_vdso_reloc(char *mapping, Elf_Addr offset) { const Elf_Ehdr *ehdr; const Elf_Shdr *shdr; Elf64_Addr *where, val; Elf_Size rtype, symidx; const Elf_Rela *rela; Elf_Addr addr, addend; int relacnt; int i, j; MPASS(offset != 0); relacnt = 0; ehdr = (const Elf_Ehdr *)mapping; shdr = (const Elf_Shdr *)(mapping + ehdr->e_shoff); for (i = 0; i < ehdr->e_shnum; i++) { switch (shdr[i].sh_type) { case SHT_REL: printf("Linux x86_64 vDSO: unexpected Rel section\n"); break; case SHT_RELA: rela = (const Elf_Rela *)(mapping + shdr[i].sh_offset); relacnt = shdr[i].sh_size / sizeof(*rela); } } for (j = 0; j < relacnt; j++, rela++) { where = (Elf_Addr *)(mapping + rela->r_offset); addend = rela->r_addend; rtype = ELF_R_TYPE(rela->r_info); symidx = ELF_R_SYM(rela->r_info); switch (rtype) { case R_X86_64_NONE: /* none */ break; case R_X86_64_RELATIVE: /* B + A */ addr = (Elf_Addr)(offset + addend); val = addr; if (*where != val) *where = val; break; case R_X86_64_IRELATIVE: printf("Linux x86_64 vDSO: unexpected ifunc relocation, " "symbol index %ld\n", symidx); break; default: printf("Linux x86_64 vDSO: unexpected relocation type %ld, " "symbol index %ld\n", rtype, symidx); } } } static Elf_Brandnote linux64_brandnote = { .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), .hdr.n_descsz = 16, .hdr.n_type = 1, .vendor = GNU_ABI_VENDOR, .flags = BN_TRANSLATE_OSREL, .trans_osrel = linux_trans_osrel }; static Elf64_Brandinfo linux_glibc2brand = { .brand = ELFOSABI_LINUX, .machine = EM_X86_64, .compat_3_brand = "Linux", .emul_path = linux_emul_path, .interp_path = "/lib64/ld-linux-x86-64.so.2", .sysvec = &elf_linux_sysvec, .interp_newpath = NULL, .brand_note = &linux64_brandnote, .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE }; static Elf64_Brandinfo linux_glibc2brandshort = { .brand = ELFOSABI_LINUX, .machine = EM_X86_64, .compat_3_brand = "Linux", .emul_path = linux_emul_path, .interp_path = "/lib64/ld-linux.so.2", .sysvec = &elf_linux_sysvec, .interp_newpath = NULL, .brand_note = &linux64_brandnote, .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE }; static Elf64_Brandinfo linux_muslbrand = { .brand = ELFOSABI_LINUX, .machine = EM_X86_64, .compat_3_brand = "Linux", .emul_path = linux_emul_path, .interp_path = "/lib/ld-musl-x86_64.so.1", .sysvec = &elf_linux_sysvec, .interp_newpath = NULL, .brand_note = &linux64_brandnote, .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE | LINUX_BI_FUTEX_REQUEUE }; static Elf64_Brandinfo *linux_brandlist[] = { &linux_glibc2brand, &linux_glibc2brandshort, &linux_muslbrand, NULL }; static int linux64_elf_modevent(module_t mod, int type, void *data) { Elf64_Brandinfo **brandinfo; int error; struct linux_ioctl_handler **lihp; error = 0; switch(type) { case MOD_LOAD: for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; ++brandinfo) if (elf64_insert_brand_entry(*brandinfo) < 0) error = EINVAL; if (error == 0) { SET_FOREACH(lihp, linux_ioctl_handler_set) linux_ioctl_register_handler(*lihp); stclohz = (stathz ? stathz : hz); if (bootverbose) printf("Linux x86-64 ELF exec handler installed\n"); } else printf("cannot insert Linux x86-64 ELF brand handler\n"); break; case MOD_UNLOAD: for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; ++brandinfo) if (elf64_brand_inuse(*brandinfo)) error = EBUSY; if (error == 0) { for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; ++brandinfo) if (elf64_remove_brand_entry(*brandinfo) < 0) error = EINVAL; } if (error == 0) { SET_FOREACH(lihp, linux_ioctl_handler_set) linux_ioctl_unregister_handler(*lihp); if (bootverbose) printf("Linux x86_64 ELF exec handler removed\n"); } else printf("Could not deinstall Linux x86_64 ELF interpreter entry\n"); break; default: return (EOPNOTSUPP); } return (error); } static moduledata_t linux64_elf_mod = { "linux64elf", linux64_elf_modevent, 0 }; DECLARE_MODULE_TIED(linux64elf, linux64_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); MODULE_DEPEND(linux64elf, linux_common, 1, 1, 1); FEATURE(linux64, "Linux 64bit support");