Messages in this thread |  | | Date | Thu, 13 Feb 2014 15:41:30 +0000 (UTC) | From | Mathieu Desnoyers <> | Subject | Re: [RFC PATCH] Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE |
| |
----- Original Message ----- > From: "Steven Rostedt" <rostedt@goodmis.org> > To: "Mathieu Desnoyers" <mathieu.desnoyers@efficios.com> > Cc: "Ingo Molnar" <mingo@kernel.org>, linux-kernel@vger.kernel.org, "Ingo Molnar" <mingo@redhat.com>, "Thomas > Gleixner" <tglx@linutronix.de>, "Rusty Russell" <rusty@rustcorp.com.au>, "David Howells" <dhowells@redhat.com>, > "Greg Kroah-Hartman" <gregkh@linuxfoundation.org> > Sent: Thursday, February 13, 2014 10:28:17 AM > Subject: Re: [RFC PATCH] Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE > > On Thu, 13 Feb 2014 15:10:14 +0000 (UTC) > Mathieu Desnoyers <mathieu.desnoyers@efficios.com> wrote: > > > ----- Original Message ----- > > > From: "Steven Rostedt" <rostedt@goodmis.org> > > > To: "Ingo Molnar" <mingo@kernel.org> > > > Cc: "Mathieu Desnoyers" <mathieu.desnoyers@efficios.com>, > > > linux-kernel@vger.kernel.org, "Ingo Molnar" > > > <mingo@redhat.com>, "Thomas Gleixner" <tglx@linutronix.de>, "Rusty > > > Russell" <rusty@rustcorp.com.au>, "David Howells" > > > <dhowells@redhat.com>, "Greg Kroah-Hartman" <gregkh@linuxfoundation.org> > > > Sent: Tuesday, February 11, 2014 11:45:34 PM > > > Subject: Re: [RFC PATCH] Fix: module signature vs tracepoints: add new > > > TAINT_UNSIGNED_MODULE > > > > > > > > [...] > > > But if the kernel expects to have signed modules, and you force a > > > module to be loaded that is not signed, then you still get that > > > "forced" module taint, which is the same one as loading a module from > > > an older kernel into a newer kernel. It's a different problem, and I > > > can see having a different taint flag be more informative to kernel > > > developers in general. I would welcome that change with or without > > > letting tracepoints be set for that module. > > > > There is one important inaccuracy in your explanation above: a > > kernel supporting signed modules, but not enforcing "sig_force", > > can load unsigned modules with a simple modprobe or insmod, without > > any "--force" argument. Therefore, tainting the module as > > "TAINT_FORCED_MODULE" is misleading. > > > > Oh! You are saying that if the kernel only *supports* signed modules, > and you load a module that is not signed, it will taint the kernel?
Yes, exactly, presuming that by "supporting" you mean CONFIG_MODULE_SIG=y. Loading an unsigned module then taints the kernel, and taints the module with TAINT_FORCED_MODULE even though "modprobe --force" was never used.
Thanks,
Mathieu
> > > -- Steve >
-- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com
|  |