/* $NetBSD: linux_ptrace.c,v 1.31.4.1 2022/08/03 11:11:32 martin Exp $ */ /*- * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Matthias Scheler and Emmanuel Dreyfus. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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: linux_ptrace.c,v 1.31.4.1 2022/08/03 11:11:32 martin Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for emul_linux */ #include #include /* for offsetof() */ /* * From Linux's include/asm-ppc/ptrace.h. * structure used for storing reg context: defined in linux_machdep.h * structure used for storing floating point context: * Linux just uses a double fpr[32], no struct */ /* * user struct for linux process - this is used for Linux ptrace emulation * most of it is junk only used by gdb * * From Linux's include/asm-ppc/user.h * * XXX u_ar0 was a struct reg in Linux/powerpc * Can't find out what a struct regs is for Linux/powerpc, * so we use a struct pt_regs instead. don't know if this is right. */ struct linux_user { struct linux_pt_regs regs; #define lusr_startgdb regs size_t u_tsize; size_t u_dsize; size_t u_ssize; unsigned long start_code; unsigned long start_data; unsigned long start_stack; long int signal; struct linux_pt_regs *u_ar0; /* help gdb find registers */ unsigned long magic; char u_comm[32]; #define lu_comm_end u_comm[31] }; #define LUSR_OFF(member) offsetof(struct linux_user, member) #define LUSR_REG_OFF(member) offsetof(struct linux_pt_regs, member) #define ISSET(t, f) ((t) & (f)) int linux_ptrace_disabled = 1; /* bitrotted */ /* XXX Check me! (From NetBSD/i386) */ int linux_sys_ptrace_arch(struct lwp *l, const struct linux_sys_ptrace_args *uap, register_t *retval) { /* { syscallarg(int) request; syscallarg(int) pid; syscallarg(int) addr; syscallarg(int) data; } */ struct proc *p = l->l_proc, *t; struct lwp *lt; struct reg *regs = NULL; struct fpreg *fpregs = NULL; struct linux_pt_regs *linux_regs = NULL; double *linux_fpreg = NULL; /* it's an array, not a struct */ int request, error, addr, i; if (linux_ptrace_disabled) return ENOSYS; error = 0; request = SCARG(uap, request); switch (request) { case LINUX_PTRACE_PEEKUSR: case LINUX_PTRACE_POKEUSR: regs = kmem_alloc(sizeof(struct reg), KM_SLEEP); break; case LINUX_PTRACE_GETREGS: case LINUX_PTRACE_SETREGS: regs = kmem_alloc(sizeof(struct reg), KM_SLEEP); linux_regs = kmem_alloc(sizeof(*linux_regs), KM_SLEEP); if (request == LINUX_PTRACE_SETREGS) { error = copyin((void *)SCARG(uap, data), linux_regs, sizeof(struct linux_pt_regs)); if (error) { goto out; } } break; case LINUX_PTRACE_GETFPREGS: case LINUX_PTRACE_SETFPREGS: fpregs = kmem_alloc(sizeof(struct fpreg), KM_SLEEP); linux_fpreg = kmem_alloc(32 * sizeof(double), KM_SLEEP); if (request == LINUX_PTRACE_SETFPREGS) { error = copyin((void *)SCARG(uap, data), linux_fpreg, 32 * sizeof(double)); if (error) { goto out; } } break; default: error = EIO; goto out; } /* Find the process we are supposed to be operating on. */ mutex_enter(proc_lock); if ((t = proc_find(SCARG(uap, pid))) == NULL) { mutex_exit(proc_lock); error = ESRCH; goto out; } mutex_enter(t->p_lock); /* * You cannot do what you want to the process if: * 1. It is not being traced at all, */ if (!ISSET(t->p_slflag, PSL_TRACED)) { mutex_exit(t->p_lock); mutex_exit(proc_lock); error = EPERM; goto out; } /* * 2. It is not being traced by _you_, or * 3. It is not currently stopped. */ if (t->p_pptr != p || t->p_stat != SSTOP || !t->p_waited) { mutex_exit(t->p_lock); mutex_exit(proc_lock); error = EBUSY; goto out; } mutex_exit(proc_lock); /* XXX: ptrace needs revamp for multi-threading support. */ if (t->p_nlwps > 1) { mutex_exit(t->p_lock); error = ENOSYS; goto out; } lt = LIST_FIRST(&t->p_lwps); *retval = 0; switch (request) { case LINUX_PTRACE_GETREGS: error = process_read_regs(lt, regs); mutex_exit(t->p_lock); if (error) { break; } memset(linux_regs, 0, sizeof(*linux_regs)); for (i = 0; i <= 31; i++) { linux_regs->lgpr[i] = regs->fixreg[i]; } linux_regs->lnip = regs->pc; linux_regs->lmsr = 0; /* XXX Is that right? */ linux_regs->lorig_gpr3 = regs->fixreg[3]; linux_regs->lctr = regs->ctr; linux_regs->llink = regs->lr; linux_regs->lxer = regs->xer; linux_regs->lccr = regs->cr; linux_regs->lmq = 0; linux_regs->ltrap = 0; linux_regs->ldar = 0; linux_regs->ldsisr = 0; linux_regs->lresult = 0; error = copyout(linux_regs, (void *)SCARG(uap, data), sizeof(struct linux_pt_regs)); break; case LINUX_PTRACE_SETREGS: for (i = 0; i <= 31; i++) { regs->fixreg[i] = linux_regs->lgpr[i]; } regs->lr = linux_regs->llink; regs->cr = linux_regs->lccr; regs->xer = linux_regs->lxer; regs->ctr = linux_regs->lctr; regs->pc = linux_regs->lnip; /* XXX */ error = process_write_regs(lt, regs); mutex_exit(t->p_lock); break; case LINUX_PTRACE_GETFPREGS: error = process_read_fpregs(lt, fpregs, NULL); mutex_exit(t->p_lock); if (error) { break; } /* Zero the contents if NetBSD fpreg structure is smaller */ if (sizeof(struct fpreg) < (32 * sizeof(double))) { memset(linux_fpreg, '\0', (32 * sizeof(double))); } memcpy(linux_fpreg, fpregs, uimin(32 * sizeof(double), sizeof(struct fpreg))); error = copyout(linux_fpreg, (void *)SCARG(uap, data), 32 * sizeof(double)); break; case LINUX_PTRACE_SETFPREGS: memset(fpregs, '\0', sizeof(struct fpreg)); memcpy(fpregs, linux_fpreg, uimin(32 * sizeof(double), sizeof(struct fpreg))); error = process_write_fpregs(lt, fpregs, sizeof fpregs); mutex_exit(t->p_lock); break; case LINUX_PTRACE_PEEKUSR: addr = SCARG(uap, addr); error = process_read_regs(lt, regs); mutex_exit(t->p_lock); if (error) { break; } error = 0; if ((addr < LUSR_OFF(lusr_startgdb)) || (addr > LUSR_OFF(lu_comm_end))) error = 1; else if (addr == LUSR_OFF(u_tsize)) *retval = p->p_vmspace->vm_tsize; else if (addr == LUSR_OFF(u_dsize)) *retval = p->p_vmspace->vm_dsize; else if (addr == LUSR_OFF(u_ssize)) *retval = p->p_vmspace->vm_ssize; else if (addr == LUSR_OFF(start_code)) *retval = (register_t) p->p_vmspace->vm_taddr; else if (addr == LUSR_OFF(start_stack)) *retval = (register_t) p->p_vmspace->vm_minsaddr; else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) *retval = regs->fixreg[addr / sizeof (register_t)]; else if (addr == LUSR_REG_OFF(lnip)) *retval = regs->pc; else if (addr == LUSR_REG_OFF(lctr)) *retval = regs->ctr; else if (addr == LUSR_REG_OFF(llink)) *retval = regs->lr; else if (addr == LUSR_REG_OFF(lxer)) *retval = regs->xer; else if (addr == LUSR_REG_OFF(lccr)) *retval = regs->cr; else if (addr == LUSR_OFF(signal)) error = 1; else if (addr == LUSR_OFF(magic)) error = 1; else if (addr == LUSR_OFF(u_comm)) error = 1; else { #ifdef DEBUG_LINUX printf("linux_ptrace: unsupported address: %d\n", addr); #endif error = 1; } if (error) { break; } error = copyout (retval, (void *)SCARG(uap, data), sizeof(*retval)); *retval = SCARG(uap, data); break; case LINUX_PTRACE_POKEUSR: /* XXX Not tested */ addr = SCARG(uap, addr); error = process_read_regs(lt, regs); if (error) { mutex_exit(t->p_lock); break; } error = 0; if ((addr < LUSR_OFF(lusr_startgdb)) || (addr > LUSR_OFF(lu_comm_end))) error = 1; else if (addr == LUSR_OFF(u_tsize)) error = 1; else if (addr == LUSR_OFF(u_dsize)) error = 1; else if (addr == LUSR_OFF(u_ssize)) error = 1; else if (addr == LUSR_OFF(start_code)) error = 1; else if (addr == LUSR_OFF(start_stack)) error = 1; else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) && (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end))) regs->fixreg[addr / sizeof (register_t)] = (register_t)SCARG(uap, data); else if (addr == LUSR_REG_OFF(lnip)) regs->pc = (register_t)SCARG(uap, data); else if (addr == LUSR_REG_OFF(lctr)) regs->ctr = (register_t)SCARG(uap, data); else if (addr == LUSR_REG_OFF(llink)) regs->lr = (register_t)SCARG(uap, data); else if (addr == LUSR_REG_OFF(lxer)) regs->xer = (register_t)SCARG(uap, data); else if (addr == LUSR_REG_OFF(lccr)) regs->cr = (register_t)SCARG(uap, data); else if (addr == LUSR_OFF(signal)) error = 1; else if (addr == LUSR_OFF(magic)) error = 1; else if (addr == LUSR_OFF(u_comm)) error = 1; else { #ifdef DEBUG_LINUX printf("linux_ptrace: unsupported address: %d\n", addr); #endif error = 1; } error = process_write_regs(lt,regs); mutex_exit(t->p_lock); break; default: mutex_exit(t->p_lock); break; } out: if (regs) kmem_free(regs, sizeof(*regs)); if (fpregs) kmem_free(fpregs, sizeof(*fpregs)); if (linux_regs) kmem_free(linux_regs, sizeof(*linux_regs)); if (linux_fpreg) kmem_free(linux_fpreg, sizeof(*linux_fpreg)); return error; }