o strace support

2 files changed, 532 insertions, 5 deletions

diff --git a/arch/mips64/kernel/ptrace.c b/arch/mips64/kernel/ptrace.c
index fb687f496..0301a66a3 100644
--- a/arch/mips64/kernel/ptrace.c
+++ b/arch/mips64/kernel/ptrace.c
@@ -1,4 +1,4 @@
-/* $Id: ptrace.c,v 1.1 1999/10/11 14:19:58 ralf Exp $
+/* $Id: ptrace.c,v 1.1 1999/12/04 03:59:00 ralf Exp $
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
@@ -8,13 +8,542 @@
  * Copyright (C) Linus Torvalds
  * Copyright (C) 1994, 1995, 1996, 1997, 1998 Ralf Baechle
  * Copyright (C) 1996 David S. Miller
+ * Copyright (C) 2000 Ulf Carlsson
  *
  * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
  * binaries.
  */
 #include <linux/kernel.h>
 #include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/user.h>
 
+#include <asm/mipsregs.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+/* Tracing a 32-bit process with a 64-bit strace and vice verca will not
+   work.  I don't know how to fix this.  */
+
+asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
+{
+	struct task_struct *child;
+	unsigned long flags;
+	int ret;
+	extern void save_fp(void*);
+
+	lock_kernel();
+#if 0
+	printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n",
+	       (int) request, (int) pid, (unsigned long) addr,
+	       (unsigned long) data);
+#endif
+	ret = -EPERM;
+	if (request == PTRACE_TRACEME) {
+		/* are we already being traced? */
+		if (current->flags & PF_PTRACED)
+			goto out;
+		/* set the ptrace bit in the process flags. */
+		current->flags |= PF_PTRACED;
+		ret = 0;
+		goto out;
+	}
+	ret = -ESRCH;
+	read_lock(&tasklist_lock);
+	child = find_task_by_pid(pid);
+	read_unlock(&tasklist_lock);	/* FIXME!!! */
+	if (!child)
+		goto out;
+	ret = -EPERM;
+	if (pid == 1)		/* you may not mess with init */
+		goto out;
+	if (request == PTRACE_ATTACH) {
+		if (child == current)
+			goto out;
+		if ((!child->dumpable ||
+		    (current->uid != child->euid) ||
+		    (current->uid != child->suid) ||
+		    (current->uid != child->uid) ||
+	 	    (current->gid != child->egid) ||
+	 	    (current->gid != child->sgid) ||
+	 	    (!cap_issubset(child->cap_permitted, current->cap_permitted)) ||
+	 	    (current->gid != child->gid)) && !capable(CAP_SYS_PTRACE))
+			goto out;
+		/* the same process cannot be attached many times */
+		if (child->flags & PF_PTRACED)
+			goto out;
+		child->flags |= PF_PTRACED;
+
+		write_lock_irqsave(&tasklist_lock, flags);
+		if (child->p_pptr != current) {
+			REMOVE_LINKS(child);
+			child->p_pptr = current;
+			SET_LINKS(child);
+		}
+		write_unlock_irqrestore(&tasklist_lock, flags);
+
+		send_sig(SIGSTOP, child, 1);
+		ret = 0;
+		goto out;
+	}
+	ret = -ESRCH;
+	if (!(child->flags & PF_PTRACED))
+		goto out;
+	if (child->state != TASK_STOPPED) {
+		if (request != PTRACE_KILL)
+			goto out;
+	}
+	if (child->p_pptr != current)
+		goto out;
+
+	switch (request) {
+	/* when I and D space are separate, these will need to be fixed. */
+	case PTRACE_PEEKTEXT: /* read word at location addr. */ 
+	case PTRACE_PEEKDATA: {
+		unsigned int tmp;
+		int copied;
+
+		copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+		ret = -EIO;
+		if (copied != sizeof(tmp))
+			break;
+		ret = put_user(tmp,(unsigned int *) data);
+		break;
+	}
+
+	/* read the word at location addr in the USER area. */
+	case PTRACE_PEEKUSR: {
+		struct pt_regs *regs;
+		unsigned int tmp;
+
+		regs = (struct pt_regs *) ((unsigned long) child +
+			KERNEL_STACK_SIZE - 32 - sizeof(struct pt_regs));
+		ret = 0;
+
+		switch (addr) {
+		case 0 ... 31:
+			tmp = regs->regs[addr];
+			break;
+		case FPR_BASE ... FPR_BASE + 31:
+			if (child->used_math) {
+				if (last_task_used_math == child) {
+					set_cp0_status(ST0_CU1, ST0_CU1);
+					save_fp(child);
+					set_cp0_status(ST0_CU1, 0);
+					last_task_used_math = NULL;
+				}
+				tmp = child->thread.fpu.hard.fp_regs[addr - 32];
+			} else {
+				tmp = -EIO;
+			}
+			break;
+		case PC:
+			tmp = regs->cp0_epc;
+			break;
+		case CAUSE:
+			tmp = regs->cp0_cause;
+			break;
+		case BADVADDR:
+			tmp = regs->cp0_badvaddr;
+			break;
+		case MMHI:
+			tmp = regs->hi;
+			break;
+		case MMLO:
+			tmp = regs->lo;
+			break;
+		case FPC_CSR:
+			tmp = child->thread.fpu.hard.control;
+			break;
+		case FPC_EIR: { /* implementation / version register */
+			unsigned int flags;
+			__save_flags(flags);
+			set_cp0_status(ST0_CU1, ST0_CU1);
+			__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
+			__restore_flags(flags);
+			break;
+		}
+		default:
+			tmp = 0;
+			ret = -EIO;
+			goto out;
+		}
+		ret = put_user(tmp, (unsigned *) data);
+		goto out;
+		}
+	/* when I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKETEXT: /* write the word at location addr. */
+	case PTRACE_POKEDATA:
+		ret = 0;
+		if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
+			break;
+		ret = -EIO;
+		break;
+
+	case PTRACE_POKEUSR: {
+		struct pt_regs *regs;
+		ret = 0;
+		regs = (struct pt_regs *) ((unsigned long) child +
+			KERNEL_STACK_SIZE - 32 - sizeof(struct pt_regs));
+
+		switch (addr) {
+		case 0 ... 31:
+			regs->regs[addr] = data;
+			break;
+		case FPR_BASE ... FPR_BASE + 31: {
+			unsigned long *fregs;
+			if (child->used_math) {
+				if (last_task_used_math == child) {
+					set_cp0_status(ST0_CU1, ST0_CU1);
+					save_fp(child);
+					set_cp0_status(ST0_CU1, 0);
+					last_task_used_math = NULL;
+					regs->cp0_status &= ~ST0_CU1;
+				}
+			} else {
+				/* FP not yet used  */
+				memset(&child->thread.fpu.hard, ~0,
+				       sizeof(child->thread.fpu.hard));
+				child->thread.fpu.hard.control = 0;
+			}
+			fregs = child->thread.fpu.hard.fp_regs;
+			fregs[addr - FPR_BASE] = data;
+			break;
+		}
+		case PC:
+			regs->cp0_epc = data;
+			break;
+		case MMHI:
+			regs->hi = data;
+			break;
+		case MMLO:
+			regs->lo = data;
+			break;
+		case FPC_CSR:
+			child->thread.fpu.hard.control = data;
+			break;
+		default:
+			/* The rest are not allowed. */
+			ret = -EIO;
+			break;
+		}
+		goto out;
+		}
+	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+	case PTRACE_CONT: { /* restart after signal. */
+		ret = -EIO;
+		if ((unsigned int) data > _NSIG)
+			break;
+		if (request == PTRACE_SYSCALL)
+			child->flags |= PF_TRACESYS;
+		else
+			child->flags &= ~PF_TRACESYS;
+		child->exit_code = data;
+		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: {
+		if (child->state == TASK_ZOMBIE)	/* already dead */
+			break;
+		child->exit_code = SIGKILL;
+		wake_up_process(child);
+		break;
+	}
+
+	case PTRACE_DETACH: { /* detach a process that was attached. */
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			break;
+		child->flags &= ~(PF_PTRACED|PF_TRACESYS);
+		child->exit_code = data;
+		write_lock_irqsave(&tasklist_lock, flags);
+		REMOVE_LINKS(child);
+		child->p_pptr = child->p_opptr;
+		SET_LINKS(child);
+		write_unlock_irqrestore(&tasklist_lock, flags);
+		wake_up_process(child);
+		ret = 0;
+		break;
+	}
+
+	default:
+		ret = -EIO;
+		break;
+	}
+out:
+	unlock_kernel();
+	return ret;
+}
+
+asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+{
+	struct task_struct *child;
+	unsigned long flags;
+	int ret;
+	extern void save_fp(void*);
+
+	lock_kernel();
+#if 0
+	printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n",
+	       (int) request, (int) pid, (unsigned long) addr,
+	       (unsigned long) data);
+#endif
+	ret = -EPERM;
+	if (request == PTRACE_TRACEME) {
+		/* are we already being traced? */
+		if (current->flags & PF_PTRACED)
+			goto out;
+		/* set the ptrace bit in the process flags. */
+		current->flags |= PF_PTRACED;
+		ret = 0;
+		goto out;
+	}
+	ret = -ESRCH;
+	read_lock(&tasklist_lock);
+	child = find_task_by_pid(pid);
+	read_unlock(&tasklist_lock);	/* FIXME!!! */
+	if (!child)
+		goto out;
+	ret = -EPERM;
+	if (pid == 1)		/* you may not mess with init */
+		goto out;
+	if (request == PTRACE_ATTACH) {
+		if (child == current)
+			goto out;
+		if ((!child->dumpable ||
+		    (current->uid != child->euid) ||
+		    (current->uid != child->suid) ||
+		    (current->uid != child->uid) ||
+	 	    (current->gid != child->egid) ||
+	 	    (current->gid != child->sgid) ||
+	 	    (!cap_issubset(child->cap_permitted, current->cap_permitted)) ||
+	 	    (current->gid != child->gid)) && !capable(CAP_SYS_PTRACE))
+			goto out;
+		/* the same process cannot be attached many times */
+		if (child->flags & PF_PTRACED)
+			goto out;
+		child->flags |= PF_PTRACED;
+
+		write_lock_irqsave(&tasklist_lock, flags);
+		if (child->p_pptr != current) {
+			REMOVE_LINKS(child);
+			child->p_pptr = current;
+			SET_LINKS(child);
+		}
+		write_unlock_irqrestore(&tasklist_lock, flags);
+
+		send_sig(SIGSTOP, child, 1);
+		ret = 0;
+		goto out;
+	}
+	ret = -ESRCH;
+	if (!(child->flags & PF_PTRACED))
+		goto out;
+	if (child->state != TASK_STOPPED) {
+		if (request != PTRACE_KILL)
+			goto out;
+	}
+	if (child->p_pptr != current)
+		goto out;
+
+	switch (request) {
+	/* when I and D space are separate, these will need to be fixed. */
+	case PTRACE_PEEKTEXT: /* read word at location addr. */ 
+	case PTRACE_PEEKDATA: {
+		unsigned long tmp;
+		int copied;
+
+		copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+		ret = -EIO;
+		if (copied != sizeof(tmp))
+			break;
+		ret = put_user(tmp,(unsigned long *) data);
+		break;
+	}
+
+	/* read the word at location addr in the USER area. */
+	case PTRACE_PEEKUSR: {
+		struct pt_regs *regs;
+		unsigned long tmp;
+
+		regs = (struct pt_regs *) ((unsigned long) child +
+			KERNEL_STACK_SIZE - 32 - sizeof(struct pt_regs));
+		ret = 0;
+
+		switch (addr) {
+		case 0 ... 31:
+			tmp = regs->regs[addr];
+			break;
+		case FPR_BASE ... FPR_BASE + 31:
+			if (child->used_math) {
+				if (last_task_used_math == child) {
+					set_cp0_status(ST0_CU1, ST0_CU1);
+					save_fp(child);
+					set_cp0_status(ST0_CU1, 0);
+					last_task_used_math = NULL;
+				}
+				tmp = child->thread.fpu.hard.fp_regs[addr - 32];
+			} else {
+				tmp = -EIO;
+			}
+			break;
+		case PC:
+			tmp = regs->cp0_epc;
+			break;
+		case CAUSE:
+			tmp = regs->cp0_cause;
+			break;
+		case BADVADDR:
+			tmp = regs->cp0_badvaddr;
+			break;
+		case MMHI:
+			tmp = regs->hi;
+			break;
+		case MMLO:
+			tmp = regs->lo;
+			break;
+		case FPC_CSR:
+			tmp = child->thread.fpu.hard.control;
+			break;
+		case FPC_EIR: { /* implementation / version register */
+			unsigned int flags;
+			__save_flags(flags);
+			set_cp0_status(ST0_CU1, ST0_CU1);
+			__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
+			__restore_flags(flags);
+			break;
+		}
+		default:
+			tmp = 0;
+			ret = -EIO;
+			goto out;
+		}
+		ret = put_user(tmp, (unsigned long *) data);
+		goto out;
+		}
+	/* when I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKETEXT: /* write the word at location addr. */
+	case PTRACE_POKEDATA:
+		ret = 0;
+		if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
+			break;
+		ret = -EIO;
+		break;
+
+	case PTRACE_POKEUSR: {
+		struct pt_regs *regs;
+		ret = 0;
+		regs = (struct pt_regs *) ((unsigned long) child +
+			KERNEL_STACK_SIZE - 32 - sizeof(struct pt_regs));
+
+		switch (addr) {
+		case 0 ... 31:
+			regs->regs[addr] = data;
+			break;
+		case FPR_BASE ... FPR_BASE + 31: {
+			unsigned long *fregs;
+			if (child->used_math) {
+				if (last_task_used_math == child) {
+					set_cp0_status(ST0_CU1, ST0_CU1);
+					save_fp(child);
+					set_cp0_status(ST0_CU1, 0);
+					last_task_used_math = NULL;
+					regs->cp0_status &= ~ST0_CU1;
+				}
+			} else {
+				/* FP not yet used  */
+				memset(&child->thread.fpu.hard, ~0,
+				       sizeof(child->thread.fpu.hard));
+				child->thread.fpu.hard.control = 0;
+			}
+			fregs = child->thread.fpu.hard.fp_regs;
+			fregs[addr - FPR_BASE] = data;
+			break;
+		}
+		case PC:
+			regs->cp0_epc = data;
+			break;
+		case MMHI:
+			regs->hi = data;
+			break;
+		case MMLO:
+			regs->lo = data;
+			break;
+		case FPC_CSR:
+			child->thread.fpu.hard.control = data;
+			break;
+		default:
+			/* The rest are not allowed. */
+			ret = -EIO;
+			break;
+		}
+		goto out;
+		}
+	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+	case PTRACE_CONT: { /* restart after signal. */
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			break;
+		if (request == PTRACE_SYSCALL)
+			child->flags |= PF_TRACESYS;
+		else
+			child->flags &= ~PF_TRACESYS;
+		child->exit_code = data;
+		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: {
+		if (child->state == TASK_ZOMBIE)	/* already dead */
+			break;
+		child->exit_code = SIGKILL;
+		wake_up_process(child);
+		break;
+	}
+
+	case PTRACE_DETACH: { /* detach a process that was attached. */
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			break;
+		child->flags &= ~(PF_PTRACED|PF_TRACESYS);
+		child->exit_code = data;
+		write_lock_irqsave(&tasklist_lock, flags);
+		REMOVE_LINKS(child);
+		child->p_pptr = child->p_opptr;
+		SET_LINKS(child);
+		write_unlock_irqrestore(&tasklist_lock, flags);
+		wake_up_process(child);
+		ret = 0;
+		break;
+	}
+
+	default:
+		ret = -EIO;
+		break;
+	}
+out:
+	unlock_kernel();
+	return ret;
+}
 
 asmlinkage void syscall_trace(void)
 {
diff --git a/arch/mips64/kernel/scall_o32.S b/arch/mips64/kernel/scall_o32.S
index 4ffda9520..bae526c1f 100644
--- a/arch/mips64/kernel/scall_o32.S
+++ b/arch/mips64/kernel/scall_o32.S
@@ -1,4 +1,4 @@
-/* $Id: scall_o32.S,v 1.15 2000/03/20 22:56:30 kanoj Exp $
+/* $Id: scall_o32.S,v 1.16 2000/03/23 00:30:53 ulfc Exp $
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
@@ -20,8 +20,6 @@
 #include <asm/stackframe.h>
 #include <asm/unistd.h>
 
-#define DEBUG_MIPS64 1
-
 /* This duplicates the definition from <linux/sched.h> */
 #define PF_TRACESYS	0x00000020	/* tracing system calls */
 
@@ -220,7 +218,7 @@ illegal_syscall:
 	sys	sys_setuid	1
 	sys	sys_getuid	0
 	sys	sys_stime	1			/* 4025 */
-	sys	sys_ni_syscall	0	/* ptrace */
+	sys	sys32_ptrace	4
 	sys	sys_alarm	1
 	sys	sys_fstat	2
 	sys	sys_ni_syscall	0