Linux-2.6.12-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!
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
new file mode 100644
index 0000000..88b306c
--- /dev/null
+++ b/kernel/ptrace.c
@@ -0,0 +1,389 @@
+/*
+ * linux/kernel/ptrace.c
+ *
+ * (C) Copyright 1999 Linus Torvalds
+ *
+ * Common interfaces for "ptrace()" which we do not want
+ * to continually duplicate across every architecture.
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
+#include <linux/ptrace.h>
+#include <linux/security.h>
+
+#include <asm/pgtable.h>
+#include <asm/uaccess.h>
+
+/*
+ * ptrace a task: make the debugger its new parent and
+ * move it to the ptrace list.
+ *
+ * Must be called with the tasklist lock write-held.
+ */
+void __ptrace_link(task_t *child, task_t *new_parent)
+{
+ if (!list_empty(&child->ptrace_list))
+ BUG();
+ if (child->parent == new_parent)
+ return;
+ list_add(&child->ptrace_list, &child->parent->ptrace_children);
+ REMOVE_LINKS(child);
+ child->parent = new_parent;
+ SET_LINKS(child);
+}
+
+/*
+ * Turn a tracing stop into a normal stop now, since with no tracer there
+ * would be no way to wake it up with SIGCONT or SIGKILL. If there was a
+ * signal sent that would resume the child, but didn't because it was in
+ * TASK_TRACED, resume it now.
+ * Requires that irqs be disabled.
+ */
+void ptrace_untrace(task_t *child)
+{
+ spin_lock(&child->sighand->siglock);
+ if (child->state == TASK_TRACED) {
+ if (child->signal->flags & SIGNAL_STOP_STOPPED) {
+ child->state = TASK_STOPPED;
+ } else {
+ signal_wake_up(child, 1);
+ }
+ }
+ spin_unlock(&child->sighand->siglock);
+}
+
+/*
+ * unptrace a task: move it back to its original parent and
+ * remove it from the ptrace list.
+ *
+ * Must be called with the tasklist lock write-held.
+ */
+void __ptrace_unlink(task_t *child)
+{
+ if (!child->ptrace)
+ BUG();
+ child->ptrace = 0;
+ if (!list_empty(&child->ptrace_list)) {
+ list_del_init(&child->ptrace_list);
+ REMOVE_LINKS(child);
+ child->parent = child->real_parent;
+ SET_LINKS(child);
+ }
+
+ if (child->state == TASK_TRACED)
+ ptrace_untrace(child);
+}
+
+/*
+ * Check that we have indeed attached to the thing..
+ */
+int ptrace_check_attach(struct task_struct *child, int kill)
+{
+ int ret = -ESRCH;
+
+ /*
+ * We take the read lock around doing both checks to close a
+ * possible race where someone else was tracing our child and
+ * detached between these two checks. After this locked check,
+ * we are sure that this is our traced child and that can only
+ * be changed by us so it's not changing right after this.
+ */
+ read_lock(&tasklist_lock);
+ if ((child->ptrace & PT_PTRACED) && child->parent == current &&
+ (!(child->ptrace & PT_ATTACHED) || child->real_parent != current)
+ && child->signal != NULL) {
+ ret = 0;
+ spin_lock_irq(&child->sighand->siglock);
+ if (child->state == TASK_STOPPED) {
+ child->state = TASK_TRACED;
+ } else if (child->state != TASK_TRACED && !kill) {
+ ret = -ESRCH;
+ }
+ spin_unlock_irq(&child->sighand->siglock);
+ }
+ read_unlock(&tasklist_lock);
+
+ if (!ret && !kill) {
+ wait_task_inactive(child);
+ }
+
+ /* All systems go.. */
+ return ret;
+}
+
+int ptrace_attach(struct task_struct *task)
+{
+ int retval;
+ task_lock(task);
+ retval = -EPERM;
+ if (task->pid <= 1)
+ goto bad;
+ if (task == current)
+ goto bad;
+ if (!task->mm)
+ goto bad;
+ if(((current->uid != task->euid) ||
+ (current->uid != task->suid) ||
+ (current->uid != task->uid) ||
+ (current->gid != task->egid) ||
+ (current->gid != task->sgid) ||
+ (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE))
+ goto bad;
+ rmb();
+ if (!task->mm->dumpable && !capable(CAP_SYS_PTRACE))
+ goto bad;
+ /* the same process cannot be attached many times */
+ if (task->ptrace & PT_PTRACED)
+ goto bad;
+ retval = security_ptrace(current, task);
+ if (retval)
+ goto bad;
+
+ /* Go */
+ task->ptrace |= PT_PTRACED | ((task->real_parent != current)
+ ? PT_ATTACHED : 0);
+ if (capable(CAP_SYS_PTRACE))
+ task->ptrace |= PT_PTRACE_CAP;
+ task_unlock(task);
+
+ write_lock_irq(&tasklist_lock);
+ __ptrace_link(task, current);
+ write_unlock_irq(&tasklist_lock);
+
+ force_sig_specific(SIGSTOP, task);
+ return 0;
+
+bad:
+ task_unlock(task);
+ return retval;
+}
+
+int ptrace_detach(struct task_struct *child, unsigned int data)
+{
+ if ((unsigned long) data > _NSIG)
+ return -EIO;
+
+ /* Architecture-specific hardware disable .. */
+ ptrace_disable(child);
+
+ /* .. re-parent .. */
+ child->exit_code = data;
+
+ write_lock_irq(&tasklist_lock);
+ __ptrace_unlink(child);
+ /* .. and wake it up. */
+ if (child->exit_state != EXIT_ZOMBIE)
+ wake_up_process(child);
+ write_unlock_irq(&tasklist_lock);
+
+ return 0;
+}
+
+/*
+ * Access another process' address space.
+ * Source/target buffer must be kernel space,
+ * Do not walk the page table directly, use get_user_pages
+ */
+
+int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
+{
+ struct mm_struct *mm;
+ struct vm_area_struct *vma;
+ struct page *page;
+ void *old_buf = buf;
+
+ mm = get_task_mm(tsk);
+ if (!mm)
+ return 0;
+
+ down_read(&mm->mmap_sem);
+ /* ignore errors, just check how much was sucessfully transfered */
+ while (len) {
+ int bytes, ret, offset;
+ void *maddr;
+
+ ret = get_user_pages(tsk, mm, addr, 1,
+ write, 1, &page, &vma);
+ if (ret <= 0)
+ break;
+
+ bytes = len;
+ offset = addr & (PAGE_SIZE-1);
+ if (bytes > PAGE_SIZE-offset)
+ bytes = PAGE_SIZE-offset;
+
+ maddr = kmap(page);
+ if (write) {
+ copy_to_user_page(vma, page, addr,
+ maddr + offset, buf, bytes);
+ set_page_dirty_lock(page);
+ } else {
+ copy_from_user_page(vma, page, addr,
+ buf, maddr + offset, bytes);
+ }
+ kunmap(page);
+ page_cache_release(page);
+ len -= bytes;
+ buf += bytes;
+ addr += bytes;
+ }
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+
+ return buf - old_buf;
+}
+
+int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
+{
+ int copied = 0;
+
+ while (len > 0) {
+ char buf[128];
+ int this_len, retval;
+
+ this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
+ retval = access_process_vm(tsk, src, buf, this_len, 0);
+ if (!retval) {
+ if (copied)
+ break;
+ return -EIO;
+ }
+ if (copy_to_user(dst, buf, retval))
+ return -EFAULT;
+ copied += retval;
+ src += retval;
+ dst += retval;
+ len -= retval;
+ }
+ return copied;
+}
+
+int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
+{
+ int copied = 0;
+
+ while (len > 0) {
+ char buf[128];
+ int this_len, retval;
+
+ this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
+ if (copy_from_user(buf, src, this_len))
+ return -EFAULT;
+ retval = access_process_vm(tsk, dst, buf, this_len, 1);
+ if (!retval) {
+ if (copied)
+ break;
+ return -EIO;
+ }
+ copied += retval;
+ src += retval;
+ dst += retval;
+ len -= retval;
+ }
+ return copied;
+}
+
+static int ptrace_setoptions(struct task_struct *child, long data)
+{
+ child->ptrace &= ~PT_TRACE_MASK;
+
+ if (data & PTRACE_O_TRACESYSGOOD)
+ child->ptrace |= PT_TRACESYSGOOD;
+
+ if (data & PTRACE_O_TRACEFORK)
+ child->ptrace |= PT_TRACE_FORK;
+
+ if (data & PTRACE_O_TRACEVFORK)
+ child->ptrace |= PT_TRACE_VFORK;
+
+ if (data & PTRACE_O_TRACECLONE)
+ child->ptrace |= PT_TRACE_CLONE;
+
+ if (data & PTRACE_O_TRACEEXEC)
+ child->ptrace |= PT_TRACE_EXEC;
+
+ if (data & PTRACE_O_TRACEVFORKDONE)
+ child->ptrace |= PT_TRACE_VFORK_DONE;
+
+ if (data & PTRACE_O_TRACEEXIT)
+ child->ptrace |= PT_TRACE_EXIT;
+
+ return (data & ~PTRACE_O_MASK) ? -EINVAL : 0;
+}
+
+static int ptrace_getsiginfo(struct task_struct *child, siginfo_t __user * data)
+{
+ siginfo_t lastinfo;
+ int error = -ESRCH;
+
+ read_lock(&tasklist_lock);
+ if (likely(child->sighand != NULL)) {
+ error = -EINVAL;
+ spin_lock_irq(&child->sighand->siglock);
+ if (likely(child->last_siginfo != NULL)) {
+ lastinfo = *child->last_siginfo;
+ error = 0;
+ }
+ spin_unlock_irq(&child->sighand->siglock);
+ }
+ read_unlock(&tasklist_lock);
+ if (!error)
+ return copy_siginfo_to_user(data, &lastinfo);
+ return error;
+}
+
+static int ptrace_setsiginfo(struct task_struct *child, siginfo_t __user * data)
+{
+ siginfo_t newinfo;
+ int error = -ESRCH;
+
+ if (copy_from_user(&newinfo, data, sizeof (siginfo_t)))
+ return -EFAULT;
+
+ read_lock(&tasklist_lock);
+ if (likely(child->sighand != NULL)) {
+ error = -EINVAL;
+ spin_lock_irq(&child->sighand->siglock);
+ if (likely(child->last_siginfo != NULL)) {
+ *child->last_siginfo = newinfo;
+ error = 0;
+ }
+ spin_unlock_irq(&child->sighand->siglock);
+ }
+ read_unlock(&tasklist_lock);
+ return error;
+}
+
+int ptrace_request(struct task_struct *child, long request,
+ long addr, long data)
+{
+ int ret = -EIO;
+
+ switch (request) {
+#ifdef PTRACE_OLDSETOPTIONS
+ case PTRACE_OLDSETOPTIONS:
+#endif
+ case PTRACE_SETOPTIONS:
+ ret = ptrace_setoptions(child, data);
+ break;
+ case PTRACE_GETEVENTMSG:
+ ret = put_user(child->ptrace_message, (unsigned long __user *) data);
+ break;
+ case PTRACE_GETSIGINFO:
+ ret = ptrace_getsiginfo(child, (siginfo_t __user *) data);
+ break;
+ case PTRACE_SETSIGINFO:
+ ret = ptrace_setsiginfo(child, (siginfo_t __user *) data);
+ break;
+ default:
+ break;
+ }
+
+ return ret;
+}