From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexei Starovoitov Subject: Re: [PATCH net-next] modules: allow modprobe load regular elf binaries Date: Mon, 5 Mar 2018 19:02:12 -0800 Message-ID: References: <20180306013457.1955486-1-ast@kernel.org> <67abc3a2-80c9-7223-37c2-e15bbecdcd00@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <67abc3a2-80c9-7223-37c2-e15bbecdcd00@infradead.org> Sender: linux-kernel-owner@vger.kernel.org To: Randy Dunlap , Alexei Starovoitov , davem@davemloft.net Cc: daniel@iogearbox.net, torvalds@linux-foundation.org, gregkh@linuxfoundation.org, mcgrof@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, linux-api@vger.kernel.org List-Id: linux-api@vger.kernel.org On 3/5/18 6:13 PM, Randy Dunlap wrote: > Hi, > > On 03/05/2018 05:34 PM, Alexei Starovoitov wrote: > >> diff --git a/kernel/module.c b/kernel/module.c >> index ad2d420024f6..6cfa35795741 100644 >> --- a/kernel/module.c >> +++ b/kernel/module.c > >> @@ -3669,6 +3683,17 @@ static int load_module(struct load_info *info, const char __user *uargs, >> if (err) >> goto free_copy; >> >> + if (info->hdr->e_type == ET_EXEC) { >> +#ifdef CONFIG_MODULE_SIG >> + if (!info->sig_ok) { >> + pr_notice_once("umh %s verification failed: signature and/or required key missing - tainting kernel\n", > > That's not a very friendly message to tell a user. "umh" eh? umh is an abbreviation known to kernel newbies: https://kernelnewbies.org/KernelProjects/usermode-helper-enhancements The rest of the message is copy paste of existing one. >> + info->file->f_path.dentry->d_name.name); >> + add_taint(TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK); >> + } > > And since the signature failed, why is it being loaded at all? because this is how regular kernel modules deal with it. sig_enforce is handled earlier. > Is this in the "--force" load path? --force forces modver and modmagic. These things don't apply here.