Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6

[powerpc.git] / kernel / ptrace.c

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 88b306c..019e04e 100644 (file)
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -16,6 +16,7 @@
 #include <linux/smp_lock.h>
 #include <linux/ptrace.h>
 #include <linux/security.h>
+#include <linux/signal.h>
 
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
@@ -117,6 +118,33 @@ int ptrace_check_attach(struct task_struct *child, int kill)
        return ret;
 }
 
+static int may_attach(struct task_struct *task)
+{
+       if (!task->mm)
+               return -EPERM;
+       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))
+               return -EPERM;
+       smp_rmb();
+       if (!task->mm->dumpable && !capable(CAP_SYS_PTRACE))
+               return -EPERM;
+
+       return security_ptrace(current, task);
+}
+
+int ptrace_may_attach(struct task_struct *task)
+{
+       int err;
+       task_lock(task);
+       err = may_attach(task);
+       task_unlock(task);
+       return !err;
+}
+
 int ptrace_attach(struct task_struct *task)
 {
        int retval;
@@ -126,22 +154,10 @@ int ptrace_attach(struct task_struct *task)
                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);
+       retval = may_attach(task);
        if (retval)
                goto bad;
 
@@ -166,7 +182,7 @@ bad:
 
 int ptrace_detach(struct task_struct *child, unsigned int data)
 {
-       if ((unsigned long) data > _NSIG)
+       if (!valid_signal(data))
                return  -EIO;
 
        /* Architecture-specific hardware disable .. */