diff options
Diffstat (limited to 'arch/arm26/kernel/ptrace.c')
-rw-r--r-- | arch/arm26/kernel/ptrace.c | 670 |
1 files changed, 0 insertions, 670 deletions
diff --git a/arch/arm26/kernel/ptrace.c b/arch/arm26/kernel/ptrace.c deleted file mode 100644 index 0fefb86970c..00000000000 --- a/arch/arm26/kernel/ptrace.c +++ /dev/null @@ -1,670 +0,0 @@ -/* - * linux/arch/arm26/kernel/ptrace.c - * - * By Ross Biro 1/23/92 - * edited by Linus Torvalds - * ARM modifications Copyright (C) 2000 Russell King - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/smp.h> -#include <linux/ptrace.h> -#include <linux/user.h> -#include <linux/security.h> -#include <linux/signal.h> - -#include <asm/uaccess.h> -#include <asm/pgtable.h> -#include <asm/system.h> -//#include <asm/processor.h> - -#include "ptrace.h" - -#define REG_PC 15 -#define REG_PSR 15 -/* - * does not yet catch signals sent when the child dies. - * in exit.c or in signal.c. - */ - -/* - * Breakpoint SWI instruction: SWI &9F0001 - */ -#define BREAKINST_ARM 0xef9f0001 - -/* - * this routine will get a word off of the processes privileged stack. - * the offset is how far from the base addr as stored in the THREAD. - * this routine assumes that all the privileged stacks are in our - * data space. - */ -static inline long get_user_reg(struct task_struct *task, int offset) -{ - return task_pt_regs(task)->uregs[offset]; -} - -/* - * this routine will put a word on the processes privileged stack. - * the offset is how far from the base addr as stored in the THREAD. - * this routine assumes that all the privileged stacks are in our - * data space. - */ -static inline int -put_user_reg(struct task_struct *task, int offset, long data) -{ - struct pt_regs newregs, *regs = task_pt_regs(task); - int ret = -EINVAL; - - newregs = *regs; - newregs.uregs[offset] = data; - - if (valid_user_regs(&newregs)) { - regs->uregs[offset] = data; - ret = 0; - } - - return ret; -} - -static inline int -read_u32(struct task_struct *task, unsigned long addr, u32 *res) -{ - int ret; - - ret = access_process_vm(task, addr, res, sizeof(*res), 0); - - return ret == sizeof(*res) ? 0 : -EIO; -} - -static inline int -read_instr(struct task_struct *task, unsigned long addr, u32 *res) -{ - int ret; - u32 val; - ret = access_process_vm(task, addr & ~3, &val, sizeof(val), 0); - ret = ret == sizeof(val) ? 0 : -EIO; - *res = val; - return ret; -} - -/* - * Get value of register `rn' (in the instruction) - */ -static unsigned long -ptrace_getrn(struct task_struct *child, unsigned long insn) -{ - unsigned int reg = (insn >> 16) & 15; - unsigned long val; - - val = get_user_reg(child, reg); - if (reg == 15) - val = pc_pointer(val + 8); //FIXME - correct for arm26? - - return val; -} - -/* - * Get value of operand 2 (in an ALU instruction) - */ -static unsigned long -ptrace_getaluop2(struct task_struct *child, unsigned long insn) -{ - unsigned long val; - int shift; - int type; - - if (insn & 1 << 25) { - val = insn & 255; - shift = (insn >> 8) & 15; - type = 3; - } else { - val = get_user_reg (child, insn & 15); - - if (insn & (1 << 4)) - shift = (int)get_user_reg (child, (insn >> 8) & 15); - else - shift = (insn >> 7) & 31; - - type = (insn >> 5) & 3; - } - - switch (type) { - case 0: val <<= shift; break; - case 1: val >>= shift; break; - case 2: - val = (((signed long)val) >> shift); - break; - case 3: - val = (val >> shift) | (val << (32 - shift)); - break; - } - return val; -} - -/* - * Get value of operand 2 (in a LDR instruction) - */ -static unsigned long -ptrace_getldrop2(struct task_struct *child, unsigned long insn) -{ - unsigned long val; - int shift; - int type; - - val = get_user_reg(child, insn & 15); - shift = (insn >> 7) & 31; - type = (insn >> 5) & 3; - - switch (type) { - case 0: val <<= shift; break; - case 1: val >>= shift; break; - case 2: - val = (((signed long)val) >> shift); - break; - case 3: - val = (val >> shift) | (val << (32 - shift)); - break; - } - return val; -} - -#define OP_MASK 0x01e00000 -#define OP_AND 0x00000000 -#define OP_EOR 0x00200000 -#define OP_SUB 0x00400000 -#define OP_RSB 0x00600000 -#define OP_ADD 0x00800000 -#define OP_ADC 0x00a00000 -#define OP_SBC 0x00c00000 -#define OP_RSC 0x00e00000 -#define OP_ORR 0x01800000 -#define OP_MOV 0x01a00000 -#define OP_BIC 0x01c00000 -#define OP_MVN 0x01e00000 - -static unsigned long -get_branch_address(struct task_struct *child, unsigned long pc, unsigned long insn) -{ - u32 alt = 0; - - switch (insn & 0x0e000000) { - case 0x00000000: - case 0x02000000: { - /* - * data processing - */ - long aluop1, aluop2, ccbit; - - if ((insn & 0xf000) != 0xf000) - break; - - aluop1 = ptrace_getrn(child, insn); - aluop2 = ptrace_getaluop2(child, insn); - ccbit = get_user_reg(child, REG_PSR) & PSR_C_BIT ? 1 : 0; - - switch (insn & OP_MASK) { - case OP_AND: alt = aluop1 & aluop2; break; - case OP_EOR: alt = aluop1 ^ aluop2; break; - case OP_SUB: alt = aluop1 - aluop2; break; - case OP_RSB: alt = aluop2 - aluop1; break; - case OP_ADD: alt = aluop1 + aluop2; break; - case OP_ADC: alt = aluop1 + aluop2 + ccbit; break; - case OP_SBC: alt = aluop1 - aluop2 + ccbit; break; - case OP_RSC: alt = aluop2 - aluop1 + ccbit; break; - case OP_ORR: alt = aluop1 | aluop2; break; - case OP_MOV: alt = aluop2; break; - case OP_BIC: alt = aluop1 & ~aluop2; break; - case OP_MVN: alt = ~aluop2; break; - } - break; - } - - case 0x04000000: - case 0x06000000: - /* - * ldr - */ - if ((insn & 0x0010f000) == 0x0010f000) { - unsigned long base; - - base = ptrace_getrn(child, insn); - if (insn & 1 << 24) { - long aluop2; - - if (insn & 0x02000000) - aluop2 = ptrace_getldrop2(child, insn); - else - aluop2 = insn & 0xfff; - - if (insn & 1 << 23) - base += aluop2; - else - base -= aluop2; - } - if (read_u32(child, base, &alt) == 0) - alt = pc_pointer(alt); - } - break; - - case 0x08000000: - /* - * ldm - */ - if ((insn & 0x00108000) == 0x00108000) { - unsigned long base; - unsigned int nr_regs; - - if (insn & (1 << 23)) { - nr_regs = hweight16(insn & 65535) << 2; - - if (!(insn & (1 << 24))) - nr_regs -= 4; - } else { - if (insn & (1 << 24)) - nr_regs = -4; - else - nr_regs = 0; - } - - base = ptrace_getrn(child, insn); - - if (read_u32(child, base + nr_regs, &alt) == 0) - alt = pc_pointer(alt); - break; - } - break; - - case 0x0a000000: { - /* - * bl or b - */ - signed long displ; - /* It's a branch/branch link: instead of trying to - * figure out whether the branch will be taken or not, - * we'll put a breakpoint at both locations. This is - * simpler, more reliable, and probably not a whole lot - * slower than the alternative approach of emulating the - * branch. - */ - displ = (insn & 0x00ffffff) << 8; - displ = (displ >> 6) + 8; - if (displ != 0 && displ != 4) - alt = pc + displ; - } - break; - } - - return alt; -} - -static int -swap_insn(struct task_struct *task, unsigned long addr, - void *old_insn, void *new_insn, int size) -{ - int ret; - - ret = access_process_vm(task, addr, old_insn, size, 0); - if (ret == size) - ret = access_process_vm(task, addr, new_insn, size, 1); - return ret; -} - -static void -add_breakpoint(struct task_struct *task, struct debug_info *dbg, unsigned long addr) -{ - int nr = dbg->nsaved; - - if (nr < 2) { - u32 new_insn = BREAKINST_ARM; - int res; - - res = swap_insn(task, addr, &dbg->bp[nr].insn, &new_insn, 4); - - if (res == 4) { - dbg->bp[nr].address = addr; - dbg->nsaved += 1; - } - } else - printk(KERN_ERR "ptrace: too many breakpoints\n"); -} - -/* - * Clear one breakpoint in the user program. We copy what the hardware - * does and use bit 0 of the address to indicate whether this is a Thumb - * breakpoint or an ARM breakpoint. - */ -static void clear_breakpoint(struct task_struct *task, struct debug_entry *bp) -{ - unsigned long addr = bp->address; - u32 old_insn; - int ret; - - ret = swap_insn(task, addr & ~3, &old_insn, - &bp->insn, 4); - - if (ret != 4 || old_insn != BREAKINST_ARM) - printk(KERN_ERR "%s:%d: corrupted ARM breakpoint at " - "0x%08lx (0x%08x)\n", task->comm, task->pid, - addr, old_insn); -} - -void ptrace_set_bpt(struct task_struct *child) -{ - struct pt_regs *regs; - unsigned long pc; - u32 insn; - int res; - - regs = task_pt_regs(child); - pc = instruction_pointer(regs); - - res = read_instr(child, pc, &insn); - if (!res) { - struct debug_info *dbg = &child->thread.debug; - unsigned long alt; - - dbg->nsaved = 0; - - alt = get_branch_address(child, pc, insn); - if (alt) - add_breakpoint(child, dbg, alt); - - /* - * Note that we ignore the result of setting the above - * breakpoint since it may fail. When it does, this is - * not so much an error, but a forewarning that we may - * be receiving a prefetch abort shortly. - * - * If we don't set this breakpoint here, then we can - * lose control of the thread during single stepping. - */ - if (!alt || predicate(insn) != PREDICATE_ALWAYS) - add_breakpoint(child, dbg, pc + 4); - } -} - -/* - * Ensure no single-step breakpoint is pending. Returns non-zero - * value if child was being single-stepped. - */ -void ptrace_cancel_bpt(struct task_struct *child) -{ - int i, nsaved = child->thread.debug.nsaved; - - child->thread.debug.nsaved = 0; - - if (nsaved > 2) { - printk("ptrace_cancel_bpt: bogus nsaved: %d!\n", nsaved); - nsaved = 2; - } - - for (i = 0; i < nsaved; i++) - clear_breakpoint(child, &child->thread.debug.bp[i]); -} - -/* - * Called by kernel/ptrace.c when detaching.. - * - * Make sure the single step bit is not set. - */ -void ptrace_disable(struct task_struct *child) -{ - child->ptrace &= ~PT_SINGLESTEP; - ptrace_cancel_bpt(child); -} - -/* - * Handle hitting a breakpoint. - */ -void ptrace_break(struct task_struct *tsk, struct pt_regs *regs) -{ - siginfo_t info; - - /* - * The PC is always left pointing at the next instruction. Fix this. - */ - regs->ARM_pc -= 4; - - if (tsk->thread.debug.nsaved == 0) - printk(KERN_ERR "ptrace: bogus breakpoint trap\n"); - - ptrace_cancel_bpt(tsk); - - info.si_signo = SIGTRAP; - info.si_errno = 0; - info.si_code = TRAP_BRKPT; - info.si_addr = (void *)instruction_pointer(regs) - 4; - - force_sig_info(SIGTRAP, &info, tsk); -} - -/* - * Read the word at offset "off" into the "struct user". We - * actually access the pt_regs stored on the kernel stack. - */ -static int ptrace_read_user(struct task_struct *tsk, unsigned long off, - unsigned long *ret) -{ - unsigned long tmp; - - if (off & 3 || off >= sizeof(struct user)) - return -EIO; - - tmp = 0; - if (off < sizeof(struct pt_regs)) - tmp = get_user_reg(tsk, off >> 2); - - return put_user(tmp, ret); -} - -/* - * Write the word at offset "off" into "struct user". We - * actually access the pt_regs stored on the kernel stack. - */ -static int ptrace_write_user(struct task_struct *tsk, unsigned long off, - unsigned long val) -{ - if (off & 3 || off >= sizeof(struct user)) - return -EIO; - - if (off >= sizeof(struct pt_regs)) - return 0; - - return put_user_reg(tsk, off >> 2, val); -} - -/* - * Get all user integer registers. - */ -static int ptrace_getregs(struct task_struct *tsk, void *uregs) -{ - struct pt_regs *regs = task_pt_regs(tsk); - - return copy_to_user(uregs, regs, sizeof(struct pt_regs)) ? -EFAULT : 0; -} - -/* - * Set all user integer registers. - */ -static int ptrace_setregs(struct task_struct *tsk, void *uregs) -{ - struct pt_regs newregs; - int ret; - - ret = -EFAULT; - if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) { - struct pt_regs *regs = task_pt_regs(tsk); - - ret = -EINVAL; - if (valid_user_regs(&newregs)) { - *regs = newregs; - ret = 0; - } - } - - return ret; -} - -/* - * Get the child FPU state. - */ -static int ptrace_getfpregs(struct task_struct *tsk, void *ufp) -{ - return copy_to_user(ufp, &task_thread_info(tsk)->fpstate, - sizeof(struct user_fp)) ? -EFAULT : 0; -} - -/* - * Set the child FPU state. - */ -static int ptrace_setfpregs(struct task_struct *tsk, void *ufp) -{ - set_stopped_child_used_math(tsk); - return copy_from_user(&task_thread_info(tsk)->fpstate, ufp, - sizeof(struct user_fp)) ? -EFAULT : 0; -} - -long arch_ptrace(struct task_struct *child, long request, long addr, long data) -{ - int ret; - - switch (request) { - /* - * read word at location "addr" in the child process. - */ - case PTRACE_PEEKTEXT: - case PTRACE_PEEKDATA: - ret = generic_ptrace_peekdata(child, addr, data); - break; - - case PTRACE_PEEKUSR: - ret = ptrace_read_user(child, addr, (unsigned long *)data); - break; - - /* - * write the word at location addr. - */ - case PTRACE_POKETEXT: - case PTRACE_POKEDATA: - ret = generic_ptrace_pokedata(child, addr, data); - break; - - case PTRACE_POKEUSR: - ret = ptrace_write_user(child, addr, data); - break; - - /* - * continue/restart and stop at next (return from) syscall - */ - case PTRACE_SYSCALL: - case PTRACE_CONT: - ret = -EIO; - if (!valid_signal(data)) - break; - if (request == PTRACE_SYSCALL) - set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - else - clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - child->exit_code = data; - /* make sure single-step breakpoint is gone. */ - child->ptrace &= ~PT_SINGLESTEP; - ptrace_cancel_bpt(child); - wake_up_process(child); - ret = 0; - break; - - /* - * make the child exit. Best I can do is send it a sigkill. - * perhaps it should be put in the status that it wants to - * exit. - */ - case PTRACE_KILL: - /* make sure single-step breakpoint is gone. */ - child->ptrace &= ~PT_SINGLESTEP; - ptrace_cancel_bpt(child); - if (child->exit_state != EXIT_ZOMBIE) { - child->exit_code = SIGKILL; - wake_up_process(child); - } - ret = 0; - break; - - /* - * execute single instruction. - */ - case PTRACE_SINGLESTEP: - ret = -EIO; - if (!valid_signal(data)) - break; - child->ptrace |= PT_SINGLESTEP; - clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - child->exit_code = data; - /* give it a chance to run. */ - wake_up_process(child); - ret = 0; - break; - - case PTRACE_DETACH: - ret = ptrace_detach(child, data); - break; - - case PTRACE_GETREGS: - ret = ptrace_getregs(child, (void *)data); - break; - - case PTRACE_SETREGS: - ret = ptrace_setregs(child, (void *)data); - break; - - case PTRACE_GETFPREGS: - ret = ptrace_getfpregs(child, (void *)data); - break; - - case PTRACE_SETFPREGS: - ret = ptrace_setfpregs(child, (void *)data); - break; - - default: - ret = ptrace_request(child, request, addr, data); - break; - } - - return ret; -} - -asmlinkage void syscall_trace(int why, struct pt_regs *regs) -{ - unsigned long ip; - - if (!test_thread_flag(TIF_SYSCALL_TRACE)) - return; - if (!(current->ptrace & PT_PTRACED)) - return; - - /* - * Save IP. IP is used to denote syscall entry/exit: - * IP = 0 -> entry, = 1 -> exit - */ - ip = regs->ARM_ip; - regs->ARM_ip = why; - - /* the 0x80 provides a way for the tracing parent to distinguish - between a syscall stop and SIGTRAP delivery */ - ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) - ? 0x80 : 0)); - /* - * this isn't the same as continuing with a signal, but it will do - * for normal use. strace only continues with a signal if the - * stopping signal is not SIGTRAP. -brl - */ - if (current->exit_code) { - send_sig(current->exit_code, current, 1); - current->exit_code = 0; - } - regs->ARM_ip = ip; -} |