#include <linux/ptrace.h>
#include <linux/security.h>
#include <linux/signal.h>
+#include <linux/audit.h>
+#include <linux/pid_namespace.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
return ret;
}
-static int may_attach(struct task_struct *task)
+int __ptrace_may_attach(struct task_struct *task)
{
/* May we inspect the given task?
* This check is used both for attaching with ptrace
return -EPERM;
smp_rmb();
if (task->mm)
- dumpable = task->mm->dumpable;
+ dumpable = get_dumpable(task->mm);
if (!dumpable && !capable(CAP_SYS_PTRACE))
return -EPERM;
{
int err;
task_lock(task);
- err = may_attach(task);
+ err = __ptrace_may_attach(task);
task_unlock(task);
return !err;
}
int ptrace_attach(struct task_struct *task)
{
int retval;
+ unsigned long flags;
+
+ audit_ptrace(task);
retval = -EPERM;
if (task->pid <= 1)
goto out;
- if (task->tgid == current->tgid)
+ if (same_thread_group(task, current))
goto out;
repeat:
* cpu's that may have task_lock).
*/
task_lock(task);
- local_irq_disable();
- if (!write_trylock(&tasklist_lock)) {
- local_irq_enable();
+ if (!write_trylock_irqsave(&tasklist_lock, flags)) {
task_unlock(task);
do {
cpu_relax();
/* the same process cannot be attached many times */
if (task->ptrace & PT_PTRACED)
goto bad;
- retval = may_attach(task);
+ retval = __ptrace_may_attach(task);
if (retval)
goto bad;
force_sig_specific(SIGSTOP, task);
bad:
- write_unlock_irq(&tasklist_lock);
+ write_unlock_irqrestore(&tasklist_lock, flags);
task_unlock(task);
out:
return retval;
/* Architecture-specific hardware disable .. */
ptrace_disable(child);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
write_lock_irq(&tasklist_lock);
/* protect against de_thread()->release_task() */
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;
case PTRACE_SETSIGINFO:
ret = ptrace_setsiginfo(child, (siginfo_t __user *) data);
break;
+ case PTRACE_DETACH: /* detach a process that was attached. */
+ ret = ptrace_detach(child, data);
+ break;
default:
break;
}
return ERR_PTR(-EPERM);
read_lock(&tasklist_lock);
- child = find_task_by_pid(pid);
+ child = find_task_by_vpid(pid);
if (child)
get_task_struct(child);
+
read_unlock(&tasklist_lock);
if (!child)
return ERR_PTR(-ESRCH);
return child;
}
+#ifndef arch_ptrace_attach
+#define arch_ptrace_attach(child) do { } while (0)
+#endif
+
#ifndef __ARCH_SYS_PTRACE
asmlinkage long sys_ptrace(long request, long pid, long addr, long data)
{
if (request == PTRACE_ATTACH) {
ret = ptrace_attach(child);
+ /*
+ * Some architectures need to do book-keeping after
+ * a ptrace attach.
+ */
+ if (!ret)
+ arch_ptrace_attach(child);
goto out_put_task_struct;
}
return ret;
}
#endif /* __ARCH_SYS_PTRACE */
+
+int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data)
+{
+ unsigned long tmp;
+ int copied;
+
+ copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
+ if (copied != sizeof(tmp))
+ return -EIO;
+ return put_user(tmp, (unsigned long __user *)data);
+}
+
+int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data)
+{
+ int copied;
+
+ copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
+ return (copied == sizeof(data)) ? 0 : -EIO;
+}