| Message ID | 20190622000358.19895-8-matthewgarrett@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Lockdown as an LSM | expand |
On Fri, Jun 21, 2019 at 05:03:36PM -0700, Matthew Garrett wrote: > From: Dave Young <dyoung@redhat.com> > > Kexec reboot in case secure boot being enabled does not keep the secure > boot mode in new kernel, so later one can load unsigned kernel via legacy > kexec_load. In this state, the system is missing the protections provided > by secure boot. > > Adding a patch to fix this by retain the secure_boot flag in original > kernel. > > secure_boot flag in boot_params is set in EFI stub, but kexec bypasses the > stub. Fixing this issue by copying secure_boot flag across kexec reboot. > > Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > Signed-off-by: David Howells <dhowells@redhat.com> > Signed-off-by: Matthew Garrett <mjg59@google.com> > cc: kexec@lists.infradead.org > --- > arch/x86/kernel/kexec-bzimage64.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c > index 22f60dd26460..4243359ac509 100644 > --- a/arch/x86/kernel/kexec-bzimage64.c > +++ b/arch/x86/kernel/kexec-bzimage64.c > @@ -182,6 +182,7 @@ setup_efi_state(struct boot_params *params, unsigned long params_load_addr, > if (efi_enabled(EFI_OLD_MEMMAP)) > return 0; > > + params->secure_boot = boot_params.secure_boot; > ei->efi_loader_signature = current_ei->efi_loader_signature; > ei->efi_systab = current_ei->efi_systab; > ei->efi_systab_hi = current_ei->efi_systab_hi; > -- > 2.22.0.410.gd8fdbe21b5-goog >
diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index 22f60dd26460..4243359ac509 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -182,6 +182,7 @@ setup_efi_state(struct boot_params *params, unsigned long params_load_addr, if (efi_enabled(EFI_OLD_MEMMAP)) return 0; + params->secure_boot = boot_params.secure_boot; ei->efi_loader_signature = current_ei->efi_loader_signature; ei->efi_systab = current_ei->efi_systab; ei->efi_systab_hi = current_ei->efi_systab_hi;