From: Peter Hessler Subject: Re: editing auto-allocated disklabels can lead to overlapping partitions To: Otto Moerbeek Cc: tech@openbsd.org Date: Sat, 30 Aug 2025 21:51:21 +0200 On 2025 Aug 27 (Wed) at 10:54:04 +0200 (+0200), Otto Moerbeek wrote: :Hi, : :as phessler experienced, editing auto-allocated labels can lead to :overlapping partitions. The culprit is the resize code, which assumes :that the partitions when sorted by letter are also sorted by offset. : :That is no longer true after the following modifications to an :auto-allocated label (with a large disk): run disklabel -AE (as the :installer does when you say you want to edit the auto-allocated :label). Then delete a partition (e.g. g containing /usr/X11R6), and :add it again. The editor will suggest to put the new g after the last :(home) partition, since the most free space is there. If you then :resize home and make it larger, it will overlap with the new g :partition. Resizing g and then resizing home would have avoided this. : :This detects the case, avoiding a malformed label by suggesting to :delete one partition of the overlapping ones. I have not found the :time or energy yet to create a better solution. But this at least :avoids silently creating overlapping partitions. : : -Otto : Yup, this would have identified the issue for me before I finished installing, which would have been enough. OK :Index: editor.c :=================================================================== :RCS file: /home/cvs/src/sbin/disklabel/editor.c,v :diff -u -p -r1.418 editor.c :--- editor.c 22 Mar 2024 21:49:52 -0000 1.418 :+++ editor.c 27 Aug 2025 08:37:28 -0000 :@@ -402,6 +402,7 @@ editor(int f) : else : fputs("Resize only implemented for auto " : "allocated labels\n", stderr); :+ has_overlap(&newlab); : break; : : case 'r': { : -- The Computer made me do it.