From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com Date: Fri, 17 Jun 2011 12:36:51 +0400 From: Vasiliy Kulikov Message-ID: <20110617083651.GA5625@albatros> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [kernel-hardening] How to temporary change 'current' (task) To: linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, Ingo Molnar , Peter Zijlstra , kernel-hardening@lists.openwall.com List-ID: Hi, I wonder whether there is a simple way to temporary switch 'current' to another task and then switch it back with minimum side effects? I need it to call "reversed" ptrace_may_access() with swapped current and target task. Introducing ptrace_task_may_access_me() would produce too much noise in LSM (it also needs reversed security_ptrace_access_check()), which is too loud for my needs. Specifically, I need it to filter taskstats and proc connector requests for a restriction of getting other processes' information: http://permalink.gmane.org/gmane.linux.kernel/1155354 As the check is handled in the context of the ptrace target process, ptrace_may_access() doesn't fit my needs. Thanks, -- Vasiliy