Commit d4eb82c7 authored Mar 25, 2006 by Chris Wright Committed by Linus Torvalds Mar 25, 2006

[PATCH] make cap_ptrace enforce PTRACE_TRACME checks



PTRACE_TRACEME doesn't have proper capabilities validation when parent is
less privileged than child.  Issue pointed out by Ram Gupta
<ram.gupta5@gmail.com>.

Note: I haven't identified a strong security issue, and it's a small ABI
change that could break apps that rely on existing behaviour (which allows
parent that is less privileged than child to ptrace when child does
PTRACE_TRACEME).

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Ram Gupta <ram.gupta5@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 12b5989b

security/commoncap.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -60,8 +60,8 @@ int cap_settime(struct timespec ts, struct timezone tz)
		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))
		if (!cap_issubset(child->cap_permitted, parent->cap_permitted) &&
		!__capable(parent, CAP_SYS_PTRACE))
		return -EPERM;
		return 0;
		}