@Ryan, I've added an SRU justification. Would you mind having a look at it, and in case it's ok uploading this SRU to plucky again?
** Description changed: + SRU Justification: + + [ Impact ] + + * lsblk on an s390x system that uses DASD disks shows no output. + + * journactl shows lsblk is blocked by apparmor: + 2025-04-15T15:02:26.048075+00:00 s5lp1-gen03 kernel: audit: type=1400 + audit(1744729346.034:270): apparmor="DENIED" operation="open" + class="file" profile="lsblk" name="/sys/devices/css0/ + 0.0.0000/0.0.0101/block/dasda/hidden" pid=2070 comm="lsblk" + requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 + + * The reason is that the unprivileged_userns profile does not + have access to /. + + * In case of running lsblk in a container the lsblk command + will even segfault, instead of returning just nothing. + + [ Fix ] + + * unprivileged_userns profile: Allow full file system access + https://gitlab.com/apparmor/apparmor/-/commit/8138bc60d18a7939af766c322586c4268e2940e3 + + [ Test Plan ] + + * Install Ubuntu Server 25.04 on IBM Z in LPAR, z/VM or KVM + using DASD ECKD disks. + + * Please notice that testing this at install time using the installer + shell is not sufficient, since the profile is not active at that time. + + * Ensure util-linux and the s390-tools are installed + (which is by default). + + * Do an lsdasd, it should list DASD ECKD disks, similar to: + $ lsdasd + Bus-ID Status Name Device Type BlkSz Size Blocks + ================================================================================ + 0.0.0200 active dasda 94:0 ECKD 4096 7042MB 1802880 + 0.0.0300 active dasdb 94:4 ECKD 4096 7042MB 1802880 + 0.0.0400 active dasdc 94:8 ECKD 4096 21128MB 5409000 + + * Now execute lsblk (and watch the journal) + + - on a system that is not patched, + one will see no output in the Terminal + (or in case of running in a container a segfault), + and messages like this in the journal: + 2025-04-15T15:02:26.048075+00:00 hwe0006 kernel: audit: type=1400 + audit(1744729346.034:270): apparmor="DENIED" operation="open" + class="file" profile="lsblk" name="/sys/devices/css0/ + 0.0.0000/0.0.0200/block/dasda/hidden" pid=2070 comm="lsblk" + requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 + ... + + - on a patched system, lsblk should provide a proper output + similar to this: + $ lsblk + NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS + loop0 7:0 0 65.4M 1 loop + loop1 7:1 0 65.4M 1 loop /snap/core22/1909 + loop2 7:2 0 39.9M 1 loop + loop3 7:3 0 98.7M 1 loop /snap/lxd/32454 + loop4 7:4 0 39.9M 1 loop /snap/snapd/23776 + loop5 7:5 0 65.4M 1 loop + loop6 7:6 0 100M 1 loop /snap/lxd/33109 + loop7 7:7 0 46.2M 1 loop /snap/snapd/24506 + loop8 7:8 0 65.4M 1 loop /snap/core22/1965 + dasda 94:0 0 20.6G 0 disk + └─dasda1 94:1 0 20.6G 0 part + └─hwe0006--vg-hwe0006--lv 253:0 0 47.1G 0 lvm / + dasdb 94:4 0 6.9G 0 disk + ├─dasdb1 94:5 0 1G 0 part /boot + └─dasdb2 94:6 0 5.9G 0 part + └─hwe0006--vg-hwe0006--lv 253:0 0 47.1G 0 lvm / + dasdc 94:8 0 20.6G 0 disk + └─dasdc1 94:9 0 20.6G 0 part + └─hwe0006--vg-hwe0006--lv 253:0 0 47.1G 0 lvm / + + * (After having done 'aa-disable lsblk' lsblk would also work + would also ork without the profile changes.) + + * As a regression test execute lsblk also on a FCP/SCSP + system, to verify that nothing has changes + (since this was not affected). + + [ Where problems could occur ] + + * The changes in profiles/apparmor.d/unprivileged_userns + are relatively small, just: + - allow file rwlkm /**, + + allow file rwlkm /{,**}, + but expand the prvilidges a bit. + + * Check if apparmor is enabled and the profile active: + sudo aa-status --enabled + sudo aa-status --show=all | grep unprivileged_userns + + * This should not have an impact on other (disk type) devices + like SCSI/FCP, but better check (see test plan, last bullet). + + [ Other Info ] + + * The modification is already included in questing. + + * The patch was tested also successfully tested in plucky on s390x. + + * Since the issue and the tests are very similar in LP#2107455 + and LP#2107402. Hence this SRU justification was added + to both of these two LP bugs. + __________ + Fresh install of 25.04 on s390x. Same happens also on upgrade from 24.10 to 25.04 lsblk returns no output journactl shows it is blocked by apparmor This works fine for SCSI devices, it fails only for DASD. ``` 2025-04-15T15:02:26.048055+00:00 s5lp1-gen03 kernel: kauditd_printk_skb: 6 callbacks suppressed 2025-04-15T15:02:26.048075+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:270): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0000/0.0.0101/block/dasda/hidden" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048077+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:271): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0000/0.0.0101/block/dasda/dev" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048078+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:272): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0003/0.0.0104/block/dasdd/hidden" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048079+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:273): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0003/0.0.0104/block/dasdd/dev" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048080+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:274): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0001/0.0.0102/block/dasdb/hidden" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048080+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:275): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0001/0.0.0102/block/dasdb/dev" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048081+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:276): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0002/0.0.0103/block/dasdc/hidden" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 2025-04-15T15:02:26.048081+00:00 s5lp1-gen03 kernel: audit: type=1400 audit(1744729346.034:277): apparmor="DENIED" operation="open" class="file" profile="lsblk" name="/sys/devices/css0/0.0.0002/0.0.0103/block/dasdc/dev" pid=2070 comm="lsblk" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 ``` - Attaching also strace -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2107402 Title: lsblk on IBM z Systems blocked by apparmor in 25.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-release-notes/+bug/2107402/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
