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charset="us-ascii"; Format="flowed" Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 1/12/24 09:06, Mimi Zohar wrote: > >>>> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c >>>> index f989f5f1933b..bf758fd5062c 100644 >>>> --- a/kernel/kexec_file.c >>>> +++ b/kernel/kexec_file.c >>>> @@ -734,6 +734,14 @@ static int kexec_calculate_store_digests(struct kimage *image) >>>> if (ksegment->kbuf == pi->purgatory_buf) >>>> continue; >>>> >>>> + /* >>>> + * Skip the segment if ima_segment_index is set and matches >>>> + * the current index >>>> + */ >>>> + if (image->is_ima_segment_index_set && >>>> + i == image->ima_segment_index) >>>> + continue; >>> With this change, the IMA segment is not included in the digest >>> calculation, nor should it be included in the digest verification. >>> However, I'm not seeing the matching code change in the digest >>> verification. >>> >> Fair question. >> >> But I don't think anything else needs to be done here. >> >> The way kexec_calculate_store_digests() and verify_sha256_digest() >> are implemented, it already skips verification of the segments if >> the segment is not part of 'purgatory_sha_regions'. >> >> In kexec_calculate_store_digests(), my change is to 'continue' when the >> segment is the IMA segment when the function is going through all the >> segments in a for loop [1]. >> >> Therefore in kexec_calculate_store_digests() - >> - crypto_shash_update() is not called for IMA segment [1]. >> - sha_regions[j] is not updated with IMA segment [1]. >> - This 'sha_regions' variable later becomes 'purgatory_sha_regions' >> in kexec_calculate_store_digests [1]. >> - and verify_sha256_digest() only verifies 'purgatory_sha_regions'[2]. >> >> Since IMA segment is not part of the 'purgatory_sha_regions', it is >> not included in the verification as part of verify_sha256_digest(). >> >>> Please make ignoring the IMA segment a separate patch. >>> >> Sure. Will do. > Thank you for the explanation. Please include in the patch description a > statement about the "sha_regions" not including the IMA segment, so nothing is > needed on the verify side. Definitely. Will do. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec