Greetings, Christopher Layne! > I noticed recently while attempting to rsync directories from one drive to > another that I was getting the familiar "NULL SID", "incorrectly ordered", > etc. type ownership issues on the destination even though I use noacl for > cygdrive mounts (I'm aware of the POSIX vs windows ACL issues, etc. hence > why I use "noacl" for cygdrive). I was able to track down the issue to a > specific combination of things that creates the problem:
> 1. I have symlinks in / for each drive pointing to /cygdrive/[a-z] via ln -s > /cygdrive/<x> /<x>. Just make cygdrive prefix / in this case. Portable apps should use /proc/cygdrive/ regardless. > 2. All symlinks are actually native reparse points as a I run with > CYGWIN=winsymlinks:nativestrict by default. > Example: > clayne@sv590:/ $ ls -lad /[a-z] > lrwxrwxrwx 1 clayne None 11 Apr 24 12:24 /c -> /cygdrive/c > lrwxrwxrwx 1 clayne None 11 Apr 24 12:24 /e -> /cygdrive/e > lrwxrwxrwx 1 clayne None 11 Apr 24 12:24 /f -> /cygdrive/f > lrwxrwxrwx 1 clayne None 11 Apr 24 12:24 /s -> /cygdrive/s What is the actual symlink target? (not what is reported by Cygwin) > 3. I issue the rsync with something like: rsync -avSHP /f/some-dir/ > /s/some-dir/ > The issue here is that it appears mount related options such as noacl are > evaluated differently when native symlinks are used. If I change the > destination to instead be "/cygdrive/s/dest/dir" then noacl works > appropriately. On top of all this, if I instead create the /s symlink as a > "cygwin" style symlink via CYGWIN=winsymlinks things also work correctly - > that is, the noacl option is used. What I would intuitively expect, atleast > within the context of acl vs noacl, is for the symlinks to be resolved first > and then mount options specific to the target resolved based off what the > symlink actually points to. In the native/nativestrict case, it appears to > be doing this in reverse and inheriting /'s standard default acl option > rather than /cygdrive's noacl option. > Footnotes on workarounds: > * I know how to workaround using the root-level symlinks in the first place > by just mounting cygdrive to /, but I'd have to update various scripts which > already use /cygdrive and I like having the "windows drives" self-contained > under /cygdrive (even though I frequently use the / level symlinks as > shorthand). See the note above about portable apps. > * I also know how to avoid the issue entirely by using /cygdrive/<x> for > the destination but the underlying issue still seems like a bug or an > oversight to me, particularly given that nativestrict behaves differently > when it comes to evaluating mount options. See... > * Another workaround would be to use non-nativestrict symlinks but I want > to preserve interoperability with native windows applications outside of > cygwin and I've learned over the years to just avoid anything that isn't > nativestrict. I'm with you here. -- With best regards, Andrey Repin Friday, April 26, 2024 10:20:43 Sorry for my terrible english... -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
