From mboxrd@z Thu Jan 1 00:00:00 1970 From: dhowells@redhat.com (David Howells) Date: Wed, 17 Jan 2018 16:34:24 +0000 Subject: [PATCH 08a/30] kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE In-Reply-To: <20180116193936.oiycvwlk5xy3gm77@dwarf.suse.cz> References: <20180116193936.oiycvwlk5xy3gm77@dwarf.suse.cz> <20180111120157.23qceywzi6omvvkb@dwarf.suse.cz> <151024863544.28329.2436580122759221600.stgit@warthog.procyon.org.uk> <151024869793.28329.4817577607302613028.stgit@warthog.procyon.org.uk> <20180111115915.dejachty3l7fwpmf@dwarf.suse.cz> <4582.1516120311@warthog.procyon.org.uk> Message-ID: <24618.1516206864@warthog.procyon.org.uk> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org Jiri Bohac wrote: > > If sig_err is -EKEYREJECTED, -EKEYEXPIRED or -EKEYREVOKED then it must fail, > > even if the signature check isn't forced. > > It wasn't my intention to fail in these cases. What additional > security does this bring? If simply stripping an invalid > signature from the image before loading will make it pass, why > should the image with an invalid signature be rejected? If there is a signature, then if we're checking signatures, in my opinion we should check it - and fail if the signature can't be parsed, is revoked, we have a key and the signature doesn't match - or even if we run out of memory. The cases for which enforcement is required are when (a) there is no signature, (b) we don't support the algorithms used, or (c) we don't have a key. If we're going to completely discard the result, why do your patches even bother to check the signature at all? David -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html