/* $NetBSD: linux32_machdep.c,v 1.47.4.1 2023/06/21 21:22:53 martin Exp $ */ /*- * Copyright (c) 2006 Emmanuel Dreyfus, 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Emmanuel Dreyfus * 4. 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 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. */ #include __KERNEL_RCSID(0, "$NetBSD: linux32_machdep.c,v 1.47.4.1 2023/06/21 21:22:53 martin Exp $"); #if defined(_KERNEL_OPT) #include "opt_user_ldt.h" #endif #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 #ifdef DEBUG_LINUX #define DPRINTF(a) uprintf a #else #define DPRINTF(a) #endif extern char linux32_sigcode[]; extern char linux32_rt_sigcode[]; extern char linux32_esigcode[]; static void linux32_save_ucontext(struct lwp *, struct trapframe *, const sigset_t *, stack_t *, struct linux32_ucontext *); static void linux32_save_sigcontext(struct lwp *, struct trapframe *, const sigset_t *, struct linux32_sigcontext *); static void linux32_rt_sendsig(const ksiginfo_t *, const sigset_t *); static void linux32_old_sendsig(const ksiginfo_t *, const sigset_t *); static int linux32_restore_sigcontext(struct lwp *, struct linux32_sigcontext *, register_t *); void linux32_sendsig(const ksiginfo_t *ksi, const sigset_t *mask) { if (SIGACTION(curproc, ksi->ksi_signo).sa_flags & SA_SIGINFO) linux32_rt_sendsig(ksi, mask); else linux32_old_sendsig(ksi, mask); return; } void linux32_old_sendsig(const ksiginfo_t *ksi, const sigset_t *mask) { struct lwp *l = curlwp; struct proc *p = l->l_proc; struct trapframe *tf; struct linux32_sigframe *fp, frame; int onstack, error; int sig = ksi->ksi_signo; sig_t catcher = SIGACTION(p, sig).sa_handler; stack_t *sas = &l->l_sigstk; tf = l->l_md.md_regs; /* Do we need to jump onto the signal stack? */ onstack = (sas->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; /* Allocate space for the signal handler context. */ if (onstack) fp = (struct linux32_sigframe *)((char *)sas->ss_sp + sas->ss_size); else fp = (struct linux32_sigframe *)tf->tf_rsp; fp--; DPRINTF(("old: onstack = %d, fp = %p sig = %d rip = 0x%lx\n", onstack, fp, sig, tf->tf_rip)); memset(&frame, 0, sizeof(frame)); /* Build stack frame for signal trampoline. */ NETBSD32PTR32(frame.sf_handler, catcher); frame.sf_sig = native_to_linux32_signo[sig]; linux32_save_sigcontext(l, tf, mask, &frame.sf_sc); sendsig_reset(l, sig); mutex_exit(p->p_lock); error = copyout(&frame, fp, sizeof(frame)); mutex_enter(p->p_lock); if (error != 0) { /* * Process has trashed its stack; give it an illegal * instruction to halt it in its tracks. */ sigexit(l, SIGILL); /* NOTREACHED */ } /* * Build context to run handler in. */ tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; tf->tf_rip = ((long)p->p_sigctx.ps_sigcode) & 0xffffffff; tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL) & 0xffffffff; tf->tf_rflags &= ~PSL_CLEARSIG & 0xffffffff; tf->tf_rsp = (long)fp & 0xffffffff; tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; /* Remember that we're now on the signal stack. */ if (onstack) sas->ss_flags |= SS_ONSTACK; return; } void linux32_rt_sendsig(const ksiginfo_t *ksi, const sigset_t *mask) { struct lwp *l = curlwp; struct proc *p = l->l_proc; struct trapframe *tf; struct linux32_rt_sigframe *fp, frame; int onstack, error; linux32_siginfo_t *lsi; int sig = ksi->ksi_signo; sig_t catcher = SIGACTION(p, sig).sa_handler; stack_t *sas = &l->l_sigstk; tf = l->l_md.md_regs; /* Do we need to jump onto the signal stack? */ onstack = (sas->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; /* Allocate space for the signal handler context. */ if (onstack) fp = (struct linux32_rt_sigframe *)((char *)sas->ss_sp + sas->ss_size); else fp = (struct linux32_rt_sigframe *)tf->tf_rsp; fp--; /* Build stack frame for signal trampoline. */ memset(&frame, 0, sizeof(frame)); NETBSD32PTR32(frame.sf_handler, catcher); frame.sf_sig = native_to_linux32_signo[sig]; NETBSD32PTR32(frame.sf_sip, &fp->sf_si); NETBSD32PTR32(frame.sf_ucp, &fp->sf_uc); DPRINTF(("rt: onstack = %d, fp = %p sig = %d rip = 0x%lx\n", onstack, fp, sig, tf->tf_rip)); lsi = &frame.sf_si; (void)memset(lsi, 0, sizeof(frame.sf_si)); lsi->lsi_errno = native_to_linux32_errno[ksi->ksi_errno]; lsi->lsi_code = native_to_linux_si_code(ksi->ksi_code); lsi->lsi_signo = frame.sf_sig; switch (lsi->lsi_signo) { case LINUX32_SIGILL: case LINUX32_SIGFPE: case LINUX32_SIGSEGV: case LINUX32_SIGBUS: case LINUX32_SIGTRAP: NETBSD32PTR32(lsi->lsi_addr, ksi->ksi_addr); break; case LINUX32_SIGCHLD: lsi->lsi_uid = ksi->ksi_uid; lsi->lsi_pid = ksi->ksi_pid; lsi->lsi_utime = ksi->ksi_utime; lsi->lsi_stime = ksi->ksi_stime; lsi->lsi_status = native_to_linux_si_status(ksi->ksi_code, ksi->ksi_status); break; case LINUX32_SIGIO: lsi->lsi_band = ksi->ksi_band; lsi->lsi_fd = ksi->ksi_fd; break; default: lsi->lsi_uid = ksi->ksi_uid; lsi->lsi_pid = ksi->ksi_pid; if (lsi->lsi_signo == LINUX32_SIGALRM || lsi->lsi_signo >= LINUX32_SIGRTMIN) NETBSD32PTR32(lsi->lsi_value.sival_ptr, ksi->ksi_value.sival_ptr); break; } /* Save register context. */ linux32_save_ucontext(l, tf, mask, sas, &frame.sf_uc); sendsig_reset(l, sig); mutex_exit(p->p_lock); error = copyout(&frame, fp, sizeof(frame)); mutex_enter(p->p_lock); if (error != 0) { /* * Process has trashed its stack; give it an illegal * instruction to halt it in its tracks. */ sigexit(l, SIGILL); /* NOTREACHED */ } /* * Build context to run handler in. */ tf->tf_fs = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; tf->tf_rip = (((long)p->p_sigctx.ps_sigcode) + (linux32_rt_sigcode - linux32_sigcode)) & 0xffffffff; tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL) & 0xffffffff; tf->tf_rflags &= ~PSL_CLEARSIG & 0xffffffff; tf->tf_rsp = (long)fp & 0xffffffff; tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL) & 0xffffffff; /* Remember that we're now on the signal stack. */ if (onstack) sas->ss_flags |= SS_ONSTACK; return; } void linux32_setregs(struct lwp *l, struct exec_package *pack, u_long stack) { struct pcb *pcb = lwp_getpcb(l); struct trapframe *tf; struct proc *p = l->l_proc; #if defined(USER_LDT) pmap_ldt_cleanup(l); #endif netbsd32_adjust_limits(p); fpu_clear(l, __Linux_NPXCW__); kpreempt_disable(); pcb->pcb_flags = PCB_COMPAT32; p->p_flag |= PK_32; l->l_md.md_flags = MDL_COMPAT32; /* force iret not sysret */ cpu_segregs32_zero(l); cpu_fsgs_reload(l, GSEL(GUDATA32_SEL, SEL_UPL), GSEL(GUDATA32_SEL, SEL_UPL)); kpreempt_enable(); tf = l->l_md.md_regs; tf->tf_rax = 0; tf->tf_rbx = (u_int32_t)p->p_psstrp; tf->tf_rcx = pack->ep_entry & 0xffffffff; tf->tf_rdx = 0; tf->tf_rsi = 0; tf->tf_rdi = 0; tf->tf_rbp = 0; tf->tf_rsp = stack & 0xffffffff; tf->tf_r8 = 0; tf->tf_r9 = 0; tf->tf_r10 = 0; tf->tf_r11 = 0; tf->tf_r12 = 0; tf->tf_r13 = 0; tf->tf_r14 = 0; tf->tf_r15 = 0; tf->tf_rip = pack->ep_entry & 0xffffffff; tf->tf_rflags = PSL_USERSET; tf->tf_cs = GSEL(GUCODE32_SEL, SEL_UPL); tf->tf_ss = GSEL(GUDATA32_SEL, SEL_UPL); tf->tf_ds = GSEL(GUDATA32_SEL, SEL_UPL); tf->tf_es = GSEL(GUDATA32_SEL, SEL_UPL); } static void linux32_save_ucontext(struct lwp *l, struct trapframe *tf, const sigset_t *mask, stack_t *sas, struct linux32_ucontext *uc) { uc->uc_flags = 0; NETBSD32PTR32(uc->uc_link, NULL); native_to_linux32_sigaltstack(&uc->uc_stack, sas); linux32_save_sigcontext(l, tf, mask, &uc->uc_mcontext); native_to_linux32_sigset(&uc->uc_sigmask, mask); (void)memset(&uc->uc_fpregs_mem, 0, sizeof(uc->uc_fpregs_mem)); } static void linux32_save_sigcontext(struct lwp *l, struct trapframe *tf, const sigset_t *mask, struct linux32_sigcontext *sc) { struct pcb *pcb = lwp_getpcb(l); /* Save register context. */ sc->sc_gs = tf->tf_gs & 0xFFFF; sc->sc_fs = tf->tf_fs & 0xFFFF; sc->sc_es = tf->tf_es & 0xFFFF; sc->sc_ds = tf->tf_ds & 0xFFFF; sc->sc_eflags = tf->tf_rflags; sc->sc_edi = tf->tf_rdi; sc->sc_esi = tf->tf_rsi; sc->sc_esp = tf->tf_rsp; sc->sc_ebp = tf->tf_rbp; sc->sc_ebx = tf->tf_rbx; sc->sc_edx = tf->tf_rdx; sc->sc_ecx = tf->tf_rcx; sc->sc_eax = tf->tf_rax; sc->sc_eip = tf->tf_rip; sc->sc_cs = tf->tf_cs & 0xFFFF; sc->sc_esp_at_signal = tf->tf_rsp; sc->sc_ss = tf->tf_ss & 0xFFFF; sc->sc_err = tf->tf_err; sc->sc_trapno = tf->tf_trapno; sc->sc_cr2 = pcb->pcb_cr2; NETBSD32PTR32(sc->sc_387, NULL); /* Save signal stack. */ /* Linux doesn't save the onstack flag in sigframe */ /* Save signal mask. */ native_to_linux32_old_sigset(&sc->sc_mask, mask); } int linux32_sys_sigreturn(struct lwp *l, const struct linux32_sys_sigreturn_args *uap, register_t *retval) { /* { syscallarg(linux32_sigcontextp_t) scp; } */ struct linux32_sigcontext ctx; int error; if ((error = copyin(SCARG_P32(uap, scp), &ctx, sizeof(ctx))) != 0) return error; return linux32_restore_sigcontext(l, &ctx, retval); } int linux32_sys_rt_sigreturn(struct lwp *l, const struct linux32_sys_rt_sigreturn_args *uap, register_t *retval) { /* { syscallarg(linux32_ucontextp_t) ucp; } */ struct linux32_ucontext ctx; int error; if ((error = copyin(SCARG_P32(uap, ucp), &ctx, sizeof(ctx))) != 0) return error; return linux32_restore_sigcontext(l, &ctx.uc_mcontext, retval); } static int linux32_restore_sigcontext(struct lwp *l, struct linux32_sigcontext *scp, register_t *retval) { struct trapframe *tf; struct proc *p = l->l_proc; stack_t *sas = &l->l_sigstk; struct pcb *pcb; sigset_t mask; ssize_t ss_gap; register_t fssel, gssel; /* Restore register context. */ tf = l->l_md.md_regs; pcb = lwp_getpcb(l); DPRINTF(("sigreturn enter rsp=0x%lx rip=0x%lx\n", tf->tf_rsp, tf->tf_rip)); /* * Check for security violations. */ if (((scp->sc_eflags ^ tf->tf_rflags) & PSL_USERSTATIC) != 0) return EINVAL; if (!VALID_USER_CSEL32(scp->sc_cs)) return EINVAL; if (scp->sc_fs != 0 && !VALID_USER_DSEL32(scp->sc_fs) && !(VALID_USER_FSEL32(scp->sc_fs) && pcb->pcb_fs != 0)) return EINVAL; if (scp->sc_gs != 0 && !VALID_USER_DSEL32(scp->sc_gs) && !(VALID_USER_GSEL32(scp->sc_gs) && pcb->pcb_gs != 0)) return EINVAL; if (scp->sc_es != 0 && !VALID_USER_DSEL32(scp->sc_es)) return EINVAL; if (!VALID_USER_DSEL32(scp->sc_ds) || !VALID_USER_DSEL32(scp->sc_ss)) return EINVAL; if (scp->sc_eip >= VM_MAXUSER_ADDRESS32) return EINVAL; gssel = (register_t)scp->sc_gs & 0xffff; fssel = (register_t)scp->sc_fs & 0xffff; cpu_fsgs_reload(l, fssel, gssel); tf->tf_es = (register_t)scp->sc_es & 0xffff; tf->tf_ds = (register_t)scp->sc_ds & 0xffff; tf->tf_rflags &= ~PSL_USER; tf->tf_rflags |= ((register_t)scp->sc_eflags & PSL_USER); tf->tf_rdi = (register_t)scp->sc_edi & 0xffffffff; tf->tf_rsi = (register_t)scp->sc_esi & 0xffffffff; tf->tf_rbp = (register_t)scp->sc_ebp & 0xffffffff; tf->tf_rbx = (register_t)scp->sc_ebx & 0xffffffff; tf->tf_rdx = (register_t)scp->sc_edx & 0xffffffff; tf->tf_rcx = (register_t)scp->sc_ecx & 0xffffffff; tf->tf_rax = (register_t)scp->sc_eax & 0xffffffff; tf->tf_rip = (register_t)scp->sc_eip & 0xffffffff; tf->tf_cs = (register_t)scp->sc_cs & 0xffff; tf->tf_rsp = (register_t)scp->sc_esp_at_signal & 0xffffffff; tf->tf_ss = (register_t)scp->sc_ss & 0xffff; mutex_enter(p->p_lock); /* Restore signal stack. */ ss_gap = (ssize_t) ((char *)NETBSD32IPTR64(scp->sc_esp_at_signal) - (char *)sas->ss_sp); if (ss_gap >= 0 && ss_gap < sas->ss_size) sas->ss_flags |= SS_ONSTACK; else sas->ss_flags &= ~SS_ONSTACK; /* Restore signal mask. */ linux32_old_to_native_sigset(&mask, &scp->sc_mask); (void) sigprocmask1(l, SIG_SETMASK, &mask, 0); mutex_exit(p->p_lock); DPRINTF(("linux32_sigreturn: rip = 0x%lx, rsp = 0x%lx, flags = 0x%lx\n", tf->tf_rip, tf->tf_rsp, tf->tf_rflags)); return EJUSTRETURN; } int linux32_sys_set_thread_area(struct lwp *l, const struct linux32_sys_set_thread_area_args *uap, register_t *retval) { /* { syscallarg(linux32_user_descp_t) desc; } */ return linux_lwp_setprivate(l, SCARG_P32(uap, desc)); } int linux32_sys_get_thread_area(struct lwp *l, const struct linux32_sys_get_thread_area_args *uap, register_t *retval) { /* { syscallarg(linux32_user_descp_t) desc; } */ /* glibc doesn't actually call this. */ return ENOSYS; } int linux32_sys_modify_ldt(struct lwp *l, const struct linux32_sys_modify_ldt_args *uap, register_t *retval) { /* { syscallarg(int) func; syscallarg(netbsd32_charp) ptr; syscallarg(netbsd32_size_t) bytecount; } */ struct linux_sys_modify_ldt_args ua; NETBSD32TO64_UAP(func); NETBSD32TOP_UAP(ptr, void *); NETBSD32TOX_UAP(bytecount, size_t); return linux_sys_modify_ldt(l, &ua, retval); }