| Message ID | 20220414014344.228523-1-coxu@redhat.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | use more system keyrings to verify arm64 and s390 kexec kernel image signature | expand |
On 04/14/22 at 09:43am, Coiby Xu wrote: > From: Michal Suchanek <msuchanek@suse.de> > > commit e23a8020ce4e ("s390/kexec_file: Signature verification prototype") > adds support for KEXEC_SIG verification with keys from platform keyring > but the built-in keys and secondary keyring are not used. > > Add support for the built-in keys and secondary keyring as x86 does. > > Fixes: e23a8020ce4e ("s390/kexec_file: Signature verification prototype") Should Cc stable kernel? Otherwise, LGTM, Acked-by: Baoquan He <bhe@redhat.com> > Cc: Philipp Rudo <prudo@linux.ibm.com> > Cc: kexec@lists.infradead.org > Cc: keyrings@vger.kernel.org > Cc: linux-security-module@vger.kernel.org > Cc: stable@kernel.org > Signed-off-by: Michal Suchanek <msuchanek@suse.de> > Reviewed-by: "Lee, Chun-Yi" <jlee@suse.com> > Signed-off-by: Coiby Xu <coxu@redhat.com> > --- > arch/s390/kernel/machine_kexec_file.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > > diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c > index 8f43575a4dd3..fc6d5f58debe 100644 > --- a/arch/s390/kernel/machine_kexec_file.c > +++ b/arch/s390/kernel/machine_kexec_file.c > @@ -31,6 +31,7 @@ int s390_verify_sig(const char *kernel, unsigned long kernel_len) > const unsigned long marker_len = sizeof(MODULE_SIG_STRING) - 1; > struct module_signature *ms; > unsigned long sig_len; > + int ret; > > /* Skip signature verification when not secure IPLed. */ > if (!ipl_secure_flag) > @@ -65,11 +66,18 @@ int s390_verify_sig(const char *kernel, unsigned long kernel_len) > return -EBADMSG; > } > > - return verify_pkcs7_signature(kernel, kernel_len, > - kernel + kernel_len, sig_len, > - VERIFY_USE_PLATFORM_KEYRING, > - VERIFYING_MODULE_SIGNATURE, > - NULL, NULL); > + ret = verify_pkcs7_signature(kernel, kernel_len, > + kernel + kernel_len, sig_len, > + VERIFY_USE_SECONDARY_KEYRING, > + VERIFYING_MODULE_SIGNATURE, > + NULL, NULL); > + if (ret == -ENOKEY && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING)) > + ret = verify_pkcs7_signature(kernel, kernel_len, > + kernel + kernel_len, sig_len, > + VERIFY_USE_PLATFORM_KEYRING, > + VERIFYING_MODULE_SIGNATURE, > + NULL, NULL); > + return ret; > } > #endif /* CONFIG_KEXEC_SIG */ > > -- > 2.34.1 > >
Currently, a problem faced by arm64 is if a kernel image is signed by a MOK key, loading it via the kexec_file_load() system call would be rejected with the error "Lockdown: kexec: kexec of unsigned images is restricted; see man kernel_lockdown.7". This happens because arm64 uses only the primary keyring that contains only kernel built-in keys to verify the kexec image. Similarly, s390 only uses platform keyring for kernel image signature verification and built-in keys and secondary keyring are not used. This patch set allows arm64 and s390 to use more system keyrings to verify kexec kernel image signature as x86 does. v6: - integrate the first three patches of "[PATCH 0/4] Unifrom keyring support across architectures and functions" from Michal [1] - improve commit message [Baoquan, Michal] - directly assign kexec_kernel_verify_pe_sig to kexec_file_ops->verify_sig [Michal] v5: - improve commit message [Baoquan] v4: - fix commit reference format issue and other checkpatch.pl warnings [Baoquan] v3: - s/arch_kexec_kernel_verify_pe_sig/kexec_kernel_verify_pe_sig [Eric] - clean up arch_kexec_kernel_verify_sig [Eric] v2: - only x86_64 and arm64 need to enable PE file signature check [Dave] [1] https://lore.kernel.org/lkml/cover.1644953683.git.msuchanek@suse.de/ Coiby Xu (3): kexec: clean up arch_kexec_kernel_verify_sig kexec, KEYS: make the code in bzImage64_verify_sig generic arm64: kexec_file: use more system keyrings to verify kernel image signature Michal Suchanek (1): kexec, KEYS, s390: Make use of built-in and secondary keyring for signature verification arch/arm64/kernel/kexec_image.c | 11 +----- arch/s390/kernel/machine_kexec_file.c | 18 +++++++--- arch/x86/kernel/kexec-bzimage64.c | 20 +---------- include/linux/kexec.h | 7 ++-- kernel/kexec_file.c | 51 ++++++++++++++++----------- 5 files changed, 50 insertions(+), 57 deletions(-)