On Wed, Aug 14, 2019 at 12:44:15PM +0200, Ilya Dryomov wrote: > On Tue, Aug 13, 2019 at 10:56 PM Tim Bishop <tim-lists@xxxxxxxxxxx> wrote: > > This email is mostly a heads up for others who might be using > > Canonical's livepatch on Ubuntu on a CephFS client. > > > > I have an Ubuntu 18.04 client with the standard kernel currently at > > version linux-image-4.15.0-54-generic 4.15.0-54.58. CephFS is mounted > > with the kernel client. Cluster is running mimic 13.2.6. I've got > > livepatch running and this evening it did an update: > > > > Aug 13 17:33:55 myclient canonical-livepatch[2396]: Client.Check > > Aug 13 17:33:55 myclient canonical-livepatch[2396]: Checking with livepatch service. > > Aug 13 17:33:55 myclient canonical-livepatch[2396]: updating last-check > > Aug 13 17:33:55 myclient canonical-livepatch[2396]: touched last check > > Aug 13 17:33:56 myclient canonical-livepatch[2396]: Applying update 54.1 for 4.15.0-54.58-generic > > Aug 13 17:33:56 myclient kernel: [3700923.970750] PKCS#7 signature not signed with a trusted key > > Aug 13 17:33:59 myclient kernel: [3700927.069945] livepatch: enabling patch 'lkp_Ubuntu_4_15_0_54_58_generic_54' > > Aug 13 17:33:59 myclient kernel: [3700927.154956] livepatch: 'lkp_Ubuntu_4_15_0_54_58_generic_54': starting patching transition > > Aug 13 17:34:01 myclient kernel: [3700928.994487] livepatch: 'lkp_Ubuntu_4_15_0_54_58_generic_54': patching complete > > Aug 13 17:34:09 myclient canonical-livepatch[2396]: Applied patch version 54.1 to 4.15.0-54.58-generic > > > > And then immediately I saw: > > > > Aug 13 17:34:18 myclient kernel: [3700945.728684] libceph: mds0 1.2.3.4:6800 socket closed (con state OPEN) > > Aug 13 17:34:18 myclient kernel: [3700946.040138] libceph: mds0 1.2.3.4:6800 socket closed (con state OPEN) > > Aug 13 17:34:19 myclient kernel: [3700947.105692] libceph: mds0 1.2.3.4:6800 socket closed (con state OPEN) > > Aug 13 17:34:20 myclient kernel: [3700948.033704] libceph: mds0 1.2.3.4:6800 socket closed (con state OPEN) > > > > And on the MDS: > > > > 2019-08-13 17:34:18.286 7ff165e75700 0 SIGN: MSG 9241367 Message signature does not match contents. > > 2019-08-13 17:34:18.286 7ff165e75700 0 SIGN: MSG 9241367Signature on message: > > 2019-08-13 17:34:18.286 7ff165e75700 0 SIGN: MSG 9241367 sig: 10517606059379971075 > > 2019-08-13 17:34:18.286 7ff165e75700 0 SIGN: MSG 9241367Locally calculated signature: > > 2019-08-13 17:34:18.286 7ff165e75700 0 SIGN: MSG 9241367 sig_check:4899837294009305543 > > 2019-08-13 17:34:18.286 7ff165e75700 0 Signature failed. > > 2019-08-13 17:34:18.286 7ff165e75700 0 -- 1.2.3.4:6800/512468759 >> 4.3.2.1:0/928333509 conn(0xe6b9500 :6800 >> s=STATE_OPEN_MESSAGE_READ_FOOTER_AND_DISPATCH pgs=2 cs=1 l=0).process >> Signature check failed > > > > Thankfully I was able to umount -f to unfreeze the client, but I have > > been unsuccessful remounting the file system using the kernel client. > > The fuse client worked fine as a workaround, but is slower. > > > > Taking a look at livepatch 54.1 I can see it touches Ceph code in the > > kernel: > > > > https://git.launchpad.net/~ubuntu-livepatch/+git/bionic-livepatches/commit/?id=3a3081c1e4c8e2e0f9f7a1ae4204eba5f38fbd29 > > > > But the relevance of those changes isn't immediately clear to me. I > > expect after a reboot it'll be fine, but as yet untested. > > These changes are very relevant. They introduce support for CEPHX_V2 > protocol, where message signatures are computed slightly differently: > same algorithm but a different set of inputs. The live-patched kernel > likely started signing using CEPHX_V2 without renegotiating. Ah - thanks for looking. Looks like something that wasn't a security issue so shouldn't have been included in the live patch. > This is a good example of how live-patching can go wrong. A reboot > should definitely help. Yup, it certainly has its tradeoffs (not having to reboot so regularly is certainly a positive, though). I've replicated on a test machine and confirmed that a reboot does indeed fix the problem. Thanks, Tim. -- Tim Bishop http://www.bishnet.net/tim/ PGP Key: 0x6C226B37FDF38D55 _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com