[PATCH] capability: Fix bug in checking capabilties in ptrace system call

["Ram Gupta" <ram.gupta5@gmail.com>]

This patch fixes a bug of ptrace for PTRACE_TRACEME request. In this
case the call is made by the child process & code needs to check the
capabilty of the parent process to trace the child process but code
incorrectly makes check for the child process.

Signed-off-by: Ram Gupta <ram.gupta5@gmail.com>

--- linux-2.6.14-patch-2.6.15/security/commoncap.c.orig Wed Mar  8 13:54:06 2006
+++ linux-2.6.14-patch-2.6.15/security/commoncap.c      Wed Mar  8 13:57:07 2006
@@ -59,9 +59,13 @@ int cap_settime(struct timespec *ts, str
 int cap_ptrace (struct task_struct *parent, struct task_struct *child)
 {
        /* Derived from arch/i386/kernel/ptrace.c:sys_ptrace. */
-       if (!cap_issubset (child->cap_permitted, current->cap_permitted) &&
-           !capable(CAP_SYS_PTRACE))
-               return -EPERM;
+       if (!cap_issubset (child->cap_permitted, current->cap_permitted)){
+               if(!security_ops->capable(parent,CAP_SYS_PTRACE)){
+                       parent->flags |= PF_SUPERPRIV;
+               }
+               else
+                       return -EPERM;
+       }
        return 0;
 }

Regards
Ram Gupta
-
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