From mboxrd@z Thu Jan 1 00:00:00 1970 From: dyoung@redhat.com (Dave Young) Date: Fri, 7 Apr 2017 11:05:45 +0800 Subject: [PATCH 09/24] kexec_file: Disable at runtime if securelevel has been set In-Reply-To: <149142335441.5101.2294976563846442575.stgit@warthog.procyon.org.uk> References: <149142326734.5101.4596394505987813763.stgit@warthog.procyon.org.uk> <149142335441.5101.2294976563846442575.stgit@warthog.procyon.org.uk> Message-ID: <20170407030545.GA4296@dhcp-128-65.nay.redhat.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org On 04/05/17 at 09:15pm, David Howells wrote: > From: Chun-Yi Lee > > When KEXEC_VERIFY_SIG is not enabled, kernel should not loads image > through kexec_file systemcall if securelevel has been set. > > This code was showed in Matthew's patch but not in git: > https://lkml.org/lkml/2015/3/13/778 > > Cc: Matthew Garrett > Signed-off-by: Chun-Yi Lee > Signed-off-by: David Howells > cc: kexec at lists.infradead.org > --- > > kernel/kexec_file.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > index b118735fea9d..f6937eecd1eb 100644 > --- a/kernel/kexec_file.c > +++ b/kernel/kexec_file.c > @@ -268,6 +268,12 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, > if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) > return -EPERM; > > + /* Don't permit images to be loaded into trusted kernels if we're not > + * going to verify the signature on them > + */ > + if (!IS_ENABLED(CONFIG_KEXEC_VERIFY_SIG) && kernel_is_locked_down()) > + return -EPERM; > + > /* Make sure we have a legal set of flags */ > if (flags != (flags & KEXEC_FILE_FLAGS)) > return -EINVAL; > > > _______________________________________________ > kexec mailing list > kexec at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec Acked-by: Dave Young Thanks Dave -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html