lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 6 May 2009 01:57:36 +0200 From: Oleg Nesterov <oleg@...hat.com> To: Andrew Morton <akpm@...ux-foundation.org> Cc: chrisw@...s-sol.org, roland@...hat.com, linux-kernel@...r.kernel.org Subject: Re: [PATCH 1/3] ptrace: ptrace_attach: check PF_KTHREAD + exit_state instead of ->mm On 05/05, Andrew Morton wrote: > > On Wed, 6 May 2009 00:47:22 +0200 > Oleg Nesterov <oleg@...hat.com> wrote: > > > - Add PF_KTHREAD check to prevent attaching to the kernel thread > > with a borrowed ->mm. > > > > With or without this change we can race with daemonize() which > > can set PF_KTHREAD or clear ->mm after ptrace_attach() does the > > check, but this doesn't matter because reparent_to_kthreadd() > > does ptrace_unlink(). > > > > - Kill "!task->mm" check. We don't really care about ->mm != NULL, > > and the task can call exit_mm() right after we drop task_lock(). > > What we need is to make sure we can't attach after exit_notify(), > > check task->exit_state != 0 instead. > > > > These patches make a mess of utrace-core.patch. Do we really want to do that? Aaaah. Sorry! forgot to clearify... These patches depend on utrace-core-kill-exclude_xtrace-logic.patch which hopefully can be folded into utrace-core.patch. In that case these changes do not depend on utrace, and they can go ahead of utrace. Is this acceptable for you ? Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists