/* $OpenBSD: syscall_mi.h,v 1.37 2024/12/27 11:57:16 mpi Exp $ */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. * * @(#)kern_xxx.c 8.2 (Berkeley) 11/14/93 */ #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #include "dt.h" #if NDT > 0 #include #endif /* * Check if a system call is entered from precisely correct location */ static inline int pin_check(struct proc *p, register_t code) { extern char sigcodecall[], sigcoderet[], sigcodecall[]; struct pinsyscall *pin = NULL, *ppin, *plibcpin; struct process *pr = p->p_p; vaddr_t addr; int error = 0; /* point at start of syscall instruction */ addr = (vaddr_t)PROC_PC(p) - (vaddr_t)(sigcoderet - sigcodecall); ppin = &pr->ps_pin; plibcpin = &pr->ps_libcpin; /* * System calls come from the following places, checks are ordered * by most common case: * 1) dynamic binary: syscalls in libc.so (in the ps_libcpin region) * 2a) static binary: syscalls in main program (in the ps_pin region) * 2b) dynamic binary: syscalls in ld.so (in the ps_pin region) * 3) sigtramp, containing only sigreturn(2) */ if (plibcpin->pn_pins && addr >= plibcpin->pn_start && addr < plibcpin->pn_end) pin = plibcpin; else if (ppin->pn_pins && addr >= ppin->pn_start && addr < ppin->pn_end) pin = ppin; else if (PROC_PC(p) == pr->ps_sigcoderet) { if (code == SYS_sigreturn) return (0); error = EPERM; goto die; } if (pin) { if (code >= pin->pn_npins || pin->pn_pins[code] == 0) error = ENOSYS; else if (pin->pn_pins[code] + pin->pn_start == addr) ; /* correct location */ else if (pin->pn_pins[code] == (u_int)-1) ; /* multiple locations, hopefully a boring operation */ else error = ENOSYS; } else error = ENOSYS; if (error == 0) return (0); die: #ifdef KTRACE if (KTRPOINT(p, KTR_PINSYSCALL)) ktrpinsyscall(p, error, code, addr); #endif KERNEL_LOCK(); /* XXX remove or simplify this uprintf() call after OpenBSD 7.5 release */ uprintf("%s[%d]: pinsyscalls addr %lx code %ld, pinoff 0x%x " "(pin%s %d %lx-%lx %lx) (libcpin%s %d %lx-%lx %lx) error %d\n", p->p_p->ps_comm, p->p_p->ps_pid, addr, code, (pin && code < pin->pn_npins) ? pin->pn_pins[code] : -1, pin == ppin ? "(Y)" : "", ppin->pn_npins, ppin->pn_start, ppin->pn_end, ppin->pn_end - ppin->pn_start, pin == plibcpin ? "(Y)" : "", plibcpin->pn_npins, plibcpin->pn_start, plibcpin->pn_end, plibcpin->pn_end - plibcpin->pn_start, error); p->p_p->ps_acflag |= APINSYS; /* Try to stop threads immediately, because this process is suspect */ if (P_HASSIBLING(p)) single_thread_set(p, SINGLE_UNWIND | SINGLE_DEEP); /* Send uncatchable SIGABRT for coredump */ sigabort(p); KERNEL_UNLOCK(); return (error); } /* * The MD setup for a system call has been done; here's the MI part. */ static inline int mi_syscall(struct proc *p, register_t code, const struct sysent *callp, register_t *argp, register_t retval[2]) { uint64_t tval; int lock = !(callp->sy_flags & SY_NOLOCK); int error, pledged; /* refresh the thread's cache of the process's creds */ refreshcreds(p); #ifdef SYSCALL_DEBUG KERNEL_LOCK(); scdebug_call(p, code, argp); KERNEL_UNLOCK(); #endif TRACEPOINT(raw_syscalls, sys_enter, code, NULL); #if NDT > 0 DT_ENTER(syscall, code, callp->sy_argsize, argp); #endif #ifdef KTRACE if (KTRPOINT(p, KTR_SYSCALL)) { /* convert to mask, then include with code */ ktrsyscall(p, code, callp->sy_argsize, argp); } #endif /* SP must be within MAP_STACK space */ if (!uvm_map_inentry(p, &p->p_spinentry, PROC_STACK(p), "[%s]%d/%d sp=%lx inside %lx-%lx: not MAP_STACK\n", uvm_map_inentry_sp, p->p_vmspace->vm_map.sserial)) return (EPERM); if ((error = pin_check(p, code))) return (error); pledged = (p->p_p->ps_flags & PS_PLEDGE); if (pledged && (error = pledge_syscall(p, code, &tval))) { KERNEL_LOCK(); error = pledge_fail(p, error, tval); KERNEL_UNLOCK(); return (error); } if (lock) KERNEL_LOCK(); error = (*callp->sy_call)(p, argp, retval); if (lock) KERNEL_UNLOCK(); return (error); } /* * Finish MI stuff on return, after the registers have been set */ static inline void mi_syscall_return(struct proc *p, register_t code, int error, const register_t retval[2]) { #ifdef SYSCALL_DEBUG KERNEL_LOCK(); scdebug_ret(p, code, error, retval); KERNEL_UNLOCK(); #endif #if NDT > 0 DT_LEAVE(syscall, code, error, retval[0], retval[1]); #endif TRACEPOINT(raw_syscalls, sys_exit, code, NULL); userret(p); #ifdef KTRACE if (KTRPOINT(p, KTR_SYSRET)) ktrsysret(p, code, error, retval); #endif } /* * Finish MI stuff for a new process/thread to return */ static inline void mi_child_return(struct proc *p) { #if defined(SYSCALL_DEBUG) || defined(KTRACE) || NDT > 0 int code = (p->p_flag & P_THREAD) ? SYS___tfork : (p->p_p->ps_flags & PS_PPWAIT) ? SYS_vfork : SYS_fork; const register_t child_retval[2] = { 0, 1 }; #endif TRACEPOINT(sched, on__cpu, NULL); #ifdef SYSCALL_DEBUG KERNEL_LOCK(); scdebug_ret(p, code, 0, child_retval); KERNEL_UNLOCK(); #endif #if NDT > 0 DT_LEAVE(syscall, code, 0, child_retval[0], child_retval[1]); #endif TRACEPOINT(raw_syscalls, sys_exit, code, NULL); userret(p); #ifdef KTRACE if (KTRPOINT(p, KTR_SYSRET)) ktrsysret(p, code, 0, child_retval); #endif } /* * Do the specific processing necessary for an AST */ static inline void mi_ast(struct proc *p, int resched) { if (p->p_flag & P_OWEUPC) { KERNEL_LOCK(); ADDUPROF(p); KERNEL_UNLOCK(); } if (resched) preempt(); /* * XXX could move call to userret() here, but * hppa calls ast() in syscall return and sh calls * it after userret() */ }