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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 00:20:36 +0200
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 00:20:36 +0200
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/um/kernel/ptrace.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/um/kernel/ptrace.c')
-rw-r--r--arch/um/kernel/ptrace.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
new file mode 100644
index 000000000000..3a99ee6d94eb
--- /dev/null
+++ b/arch/um/kernel/ptrace.c
@@ -0,0 +1,388 @@
+/*
+ * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/sched.h"
+#include "linux/mm.h"
+#include "linux/errno.h"
+#include "linux/smp_lock.h"
+#include "linux/security.h"
+#include "linux/ptrace.h"
+#include "linux/audit.h"
+#ifdef CONFIG_PROC_MM
+#include "linux/proc_mm.h"
+#endif
+#include "asm/ptrace.h"
+#include "asm/uaccess.h"
+#include "kern_util.h"
+#include "skas_ptrace.h"
+#include "sysdep/ptrace.h"
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ child->ptrace &= ~PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+}
+
+long sys_ptrace(long request, long pid, long addr, long data)
+{
+ struct task_struct *child;
+ int i, ret;
+
+ lock_kernel();
+ ret = -EPERM;
+ if (request == PTRACE_TRACEME) {
+ /* are we already being traced? */
+ if (current->ptrace & PT_PTRACED)
+ goto out;
+
+ ret = security_ptrace(current->parent, current);
+ if (ret)
+ goto out;
+
+ /* set the ptrace bit in the process flags. */
+ current->ptrace |= PT_PTRACED;
+ ret = 0;
+ goto out;
+ }
+ ret = -ESRCH;
+ read_lock(&tasklist_lock);
+ child = find_task_by_pid(pid);
+ if (child)
+ get_task_struct(child);
+ read_unlock(&tasklist_lock);
+ if (!child)
+ goto out;
+
+ ret = -EPERM;
+ if (pid == 1) /* you may not mess with init */
+ goto out_tsk;
+
+ if (request == PTRACE_ATTACH) {
+ ret = ptrace_attach(child);
+ goto out_tsk;
+ }
+
+ ret = ptrace_check_attach(child, request == PTRACE_KILL);
+ if (ret < 0)
+ goto out_tsk;
+
+ 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;
+
+ ret = -EIO;
+ copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+ if (copied != sizeof(tmp))
+ break;
+ ret = put_user(tmp, (unsigned long __user *) data);
+ break;
+ }
+
+ /* read the word at location addr in the USER area. */
+ case PTRACE_PEEKUSR: {
+ unsigned long tmp;
+
+ ret = -EIO;
+ if ((addr & 3) || addr < 0)
+ break;
+
+ tmp = 0; /* Default return condition */
+ if(addr < MAX_REG_OFFSET){
+ tmp = getreg(child, addr);
+ }
+ else if((addr >= offsetof(struct user, u_debugreg[0])) &&
+ (addr <= offsetof(struct user, u_debugreg[7]))){
+ addr -= offsetof(struct user, u_debugreg[0]);
+ addr = addr >> 2;
+ tmp = child->thread.arch.debugregs[addr];
+ }
+ ret = put_user(tmp, (unsigned long __user *) data);
+ break;
+ }
+
+ /* 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 = -EIO;
+ if (access_process_vm(child, addr, &data, sizeof(data),
+ 1) != sizeof(data))
+ break;
+ ret = 0;
+ break;
+
+ case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
+ ret = -EIO;
+ if ((addr & 3) || addr < 0)
+ break;
+
+ if (addr < MAX_REG_OFFSET) {
+ ret = putreg(child, addr, data);
+ break;
+ }
+#if 0 /* XXX x86_64 */
+ else if((addr >= offsetof(struct user, u_debugreg[0])) &&
+ (addr <= offsetof(struct user, u_debugreg[7]))){
+ addr -= offsetof(struct user, u_debugreg[0]);
+ addr = addr >> 2;
+ if((addr == 4) || (addr == 5)) break;
+ child->thread.arch.debugregs[addr] = data;
+ ret = 0;
+ }
+#endif
+
+ break;
+
+ 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;
+
+ child->ptrace &= ~PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+ 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;
+ 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: {
+ ret = 0;
+ if (child->exit_state == EXIT_ZOMBIE) /* already dead */
+ break;
+
+ child->ptrace &= ~PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+ child->exit_code = SIGKILL;
+ wake_up_process(child);
+ break;
+ }
+
+ case PTRACE_SINGLESTEP: { /* set the trap flag. */
+ ret = -EIO;
+ if ((unsigned long) data > _NSIG)
+ break;
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ child->ptrace |= PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+ child->exit_code = data;
+ /* give it a chance to run. */
+ wake_up_process(child);
+ ret = 0;
+ break;
+ }
+
+ case PTRACE_DETACH:
+ /* detach a process that was attached. */
+ ret = ptrace_detach(child, data);
+ break;
+
+#ifdef PTRACE_GETREGS
+ case PTRACE_GETREGS: { /* Get all gp regs from the child. */
+ if (!access_ok(VERIFY_WRITE, (unsigned long *)data,
+ MAX_REG_OFFSET)) {
+ ret = -EIO;
+ break;
+ }
+ for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
+ __put_user(getreg(child, i),
+ (unsigned long __user *) data);
+ data += sizeof(long);
+ }
+ ret = 0;
+ break;
+ }
+#endif
+#ifdef PTRACE_SETREGS
+ case PTRACE_SETREGS: { /* Set all gp regs in the child. */
+ unsigned long tmp = 0;
+ if (!access_ok(VERIFY_READ, (unsigned *)data,
+ MAX_REG_OFFSET)) {
+ ret = -EIO;
+ break;
+ }
+ for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
+ __get_user(tmp, (unsigned long __user *) data);
+ putreg(child, i, tmp);
+ data += sizeof(long);
+ }
+ ret = 0;
+ break;
+ }
+#endif
+#ifdef PTRACE_GETFPREGS
+ case PTRACE_GETFPREGS: /* Get the child FPU state. */
+ ret = get_fpregs(data, child);
+ break;
+#endif
+#ifdef PTRACE_SETFPREGS
+ case PTRACE_SETFPREGS: /* Set the child FPU state. */
+ ret = set_fpregs(data, child);
+ break;
+#endif
+#ifdef PTRACE_GETFPXREGS
+ case PTRACE_GETFPXREGS: /* Get the child FPU state. */
+ ret = get_fpxregs(data, child);
+ break;
+#endif
+#ifdef PTRACE_SETFPXREGS
+ case PTRACE_SETFPXREGS: /* Set the child FPU state. */
+ ret = set_fpxregs(data, child);
+ break;
+#endif
+ case PTRACE_FAULTINFO: {
+ struct ptrace_faultinfo fault;
+
+ fault = ((struct ptrace_faultinfo)
+ { .is_write = child->thread.err,
+ .addr = child->thread.cr2 });
+ ret = copy_to_user((unsigned long __user *) data, &fault,
+ sizeof(fault));
+ if(ret)
+ break;
+ break;
+ }
+ case PTRACE_SIGPENDING:
+ ret = copy_to_user((unsigned long __user *) data,
+ &child->pending.signal,
+ sizeof(child->pending.signal));
+ break;
+
+ case PTRACE_LDT: {
+ struct ptrace_ldt ldt;
+
+ if(copy_from_user(&ldt, (unsigned long __user *) data,
+ sizeof(ldt))){
+ ret = -EIO;
+ break;
+ }
+
+ /* This one is confusing, so just punt and return -EIO for
+ * now
+ */
+ ret = -EIO;
+ break;
+ }
+#ifdef CONFIG_PROC_MM
+ case PTRACE_SWITCH_MM: {
+ struct mm_struct *old = child->mm;
+ struct mm_struct *new = proc_mm_get_mm(data);
+
+ if(IS_ERR(new)){
+ ret = PTR_ERR(new);
+ break;
+ }
+
+ atomic_inc(&new->mm_users);
+ child->mm = new;
+ child->active_mm = new;
+ mmput(old);
+ ret = 0;
+ break;
+ }
+#endif
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+ out_tsk:
+ put_task_struct(child);
+ out:
+ unlock_kernel();
+ return ret;
+}
+
+void send_sigtrap(struct task_struct *tsk, union uml_pt_regs *regs,
+ int error_code)
+{
+ struct siginfo info;
+
+ memset(&info, 0, sizeof(info));
+ info.si_signo = SIGTRAP;
+ info.si_code = TRAP_BRKPT;
+
+ /* User-mode eip? */
+ info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL;
+
+ /* Send us the fakey SIGTRAP */
+ force_sig_info(SIGTRAP, &info, tsk);
+}
+
+/* XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and
+ * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
+ */
+void syscall_trace(union uml_pt_regs *regs, int entryexit)
+{
+ int is_singlestep = (current->ptrace & PT_DTRACE) && entryexit;
+ int tracesysgood;
+
+ if (unlikely(current->audit_context)) {
+ if (!entryexit)
+ audit_syscall_entry(current,
+ UPT_SYSCALL_NR(&regs->regs),
+ UPT_SYSCALL_ARG1(&regs->regs),
+ UPT_SYSCALL_ARG2(&regs->regs),
+ UPT_SYSCALL_ARG3(&regs->regs),
+ UPT_SYSCALL_ARG4(&regs->regs));
+ else
+ audit_syscall_exit(current,
+ UPT_SYSCALL_RET(&regs->regs));
+ }
+
+ /* Fake a debug trap */
+ if (is_singlestep)
+ send_sigtrap(current, regs, 0);
+
+ if (!test_thread_flag(TIF_SYSCALL_TRACE))
+ return;
+
+ if (!(current->ptrace & PT_PTRACED))
+ return;
+
+ /* the 0x80 provides a way for the tracing parent to distinguish
+ between a syscall stop and SIGTRAP delivery */
+ tracesysgood = (current->ptrace & PT_TRACESYSGOOD);
+ ptrace_notify(SIGTRAP | (tracesysgood ? 0x80 : 0));
+
+ if (entryexit) /* force do_signal() --> is_syscall() */
+ set_thread_flag(TIF_SIGPENDING);
+
+ /* 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;
+ }
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */