> From: Mimi Zohar [mailto:zohar@xxxxxxxxxxxxx] > Sent: Friday, August 21, 2020 8:45 PM > On Thu, 2020-06-18 at 18:01 +0200, Roberto Sassu wrote: > > Public keys do not need to be appraised by IMA as the restriction on the > > IMA/EVM keyrings ensures that a key is loaded only if it is signed with a > > key in the primary or secondary keyring. > > > > However, when evm_load_x509() is loaded, appraisal is already enabled > and > > a valid IMA signature must be added to the EVM key to pass verification. > > > > Since the restriction is applied on both IMA and EVM keyrings, it is safe > > to disable appraisal also when the EVM key is loaded. This patch calls > > evm_load_x509() inside ima_load_x509() if CONFIG_IMA_LOAD_X509 is > defined. > > > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > > --- > > security/integrity/iint.c | 2 ++ > > security/integrity/ima/ima_init.c | 4 ++++ > > 2 files changed, 6 insertions(+) > > > > diff --git a/security/integrity/iint.c b/security/integrity/iint.c > > index e12c4900510f..4765a266ba96 100644 > > --- a/security/integrity/iint.c > > +++ b/security/integrity/iint.c > > @@ -212,7 +212,9 @@ int integrity_kernel_read(struct file *file, loff_t > offset, > > void __init integrity_load_keys(void) > > { > > ima_load_x509(); > > +#ifndef CONFIG_IMA_LOAD_X509 > > evm_load_x509(); > > +#endif > > } > > > > static int __init integrity_fs_init(void) > > diff --git a/security/integrity/ima/ima_init.c > b/security/integrity/ima/ima_init.c > > index 4902fe7bd570..9d29a1680da8 100644 > > --- a/security/integrity/ima/ima_init.c > > +++ b/security/integrity/ima/ima_init.c > > @@ -106,6 +106,10 @@ void __init ima_load_x509(void) > > > > ima_policy_flag &= ~unset_flags; > > integrity_load_x509(INTEGRITY_KEYRING_IMA, > CONFIG_IMA_X509_PATH); > > + > > + /* load also EVM key to avoid appraisal */ > > + evm_load_x509(); > > + > > ima_policy_flag |= unset_flags; > > } > > #endif > > As much as possible IMA and EVM should remain independent of each > other. Modifying integrity_load_x509() doesn't help. This looks like > a good reason for calling another EVM function from within IMA. Can I add your Reviewed-by? Thanks Roberto HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063 Managing Director: Li Peng, Li Jian, Shi Yanli
