On Fri, 2017-04-07 at 11:05 +0800, Dave Young wrote: > On 04/05/17 at 09:15pm, David Howells wrote: > > From: Chun-Yi Lee <joeyli.ker...@gmail.com> > > > > 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 <mj...@srcf.ucam.org> > > Signed-off-by: Chun-Yi Lee <j...@suse.com> > > Signed-off-by: David Howells <dhowe...@redhat.com> > > cc: ke...@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; > > + > >
IMA can be used to verify file signatures too, based on the LSM hooks in kernel_read_file_from_fd(). CONFIG_KEXEC_VERIFY_SIG should not be required. Mimi > /* Make sure we have a legal set of flags */ > > if (flags != (flags & KEXEC_FILE_FLAGS)) > > return -EINVAL; > > > > > > _______________________________________________ > > kexec mailing list > > ke...@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/kexec > > Acked-by: Dave Young <dyo...@redhat.com> > > Thanks > Dave > -- > To unsubscribe from this list: send the line "unsubscribe > linux-security-module" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
