Date: Sat, 26 May 2018 10:21:09 +0100 From: Stilez Stilezy <stilezy@gmail.com> To: freebsd-fs <freebsd-fs@freebsd.org> Subject: Apparent incorrect behaviour in NFSv4 ACL processing in 11.1-REL. Expected/correct behaviour or bug? Message-ID: <CAFwhr76cHm7tLnHAKdvvLhHxFOg0BKQNbfai61pxvNF-NSbzHw@mail.gmail.com>
next in thread | raw e-mail | index | archive | help
I've managed to get reproducible behaviour on FreeBSD 11.1, showing that in some cases: 1) an NFSv4 ACE that shouldn't affect the access granted to an account, does seem to affect it; and 2) this behaviour can be worked around by giving the account "ra" instead or "r" even though from docs, "a" shouldn't be relevant to the access affected. It looks like a bug to me, but perhaps there's some non-bug explanation for it, or it's my lack of knowledge? Test output follows below. I've interspersed commands/output from two parallel sessions, one (#) privileged, the other (%) unprivileged. Comments are in ALL-CAPS. Any light on what's going on would be appreciated - thanks. Stilez. COMMENT: CHECK MOUNT OPTIONS ARE NORMAL, AND SET UP A CLEAN TEST DIR + CONTENTS # mount | grep testpool testpool on /mnt/testpool (zfs, local, noatime, nfsv4acls) testpool/User_files on /mnt/testpool/User_files (zfs, local, noatime, nfsv4acls) # mkdir /mnt/testpool/test5; mkdir /mnt/testpool/test5/subdir; touch /mnt/testpool/test5/subfile; ls -1F /mnt/testpool/test5 subfile subdir/ COMMENT: CHECK OUR DIR IS READABLE WITH A NEWLY CREATED UNPRIVILEGED ACCOUNT IN ANOTHER SSH WINDOW: % ls /mnt/testpool/test5 subdir subfile COMMENT: QUICKLY SET UP SOME ACLS TO EXHIBIT THE BEHAVIOUR: COMMENT: THESE ACLS SHOULD ALLOW THE UNPRIVILEGED ACCOUNT TO READ THE DIR BUT NOTHING ELSE (AND THEY DO - SO FAR IT'S OK) # setfacl -a 0 everyone@:r::allow,owner@::allow,group@::allow,everyone@::allow /mnt/testpool/test5 ; \ setfacl -x 4 /mnt/testpool/test5; setfacl -x 4 /mnt/testpool/test5; setfacl -x 4 /mnt/testpool/test5; getfacl /mnt/testpool/test5 # file: /mnt/testpool/test5 # owner: root # group: wheel everyone@:r-------------:-------:allow owner@:--------------:-------:allow group@:--------------:-------:allow everyone@:--------------:-------:allow COMMENT: CHECK THAT OUR UNPRIVILEGED ACCOUNT CAN READ THE DIR AS EXPECTED, AND ONLY NEEDS "r" TO DO SO: % ls /mnt/testpool/test5 subdir subfile COMMENT: SO FAR ALL IS OK. COMMENT: NOW ADD A SINGLE ACE THAT SHOULDN'T AFFECT OUR UNPRIVILEGED ACCOUNT AT ALL COMMENT: NOTHING SHOULD HAVE CHANGED FOR OUR UNPRIVILEGED ACCOUNT, BUT IT NOW CANNOT READ THE DIR. # setfacl -a 1 group:nogroup:rwxpDda-R-c---:fd-----:allow /mnt/testpool/test5 ; getfacl /mnt/testpool/test5 # file: /mnt/testpool/test5 # owner: root # group: wheel everyone@:r-------------:-------:allow group:nogroup:rwxpDda-R-c---:fd-----:allow owner@:--------------:-------:allow group@:--------------:-------:allow everyone@:--------------:-------:allow % ls /mnt/testpool/test5 ls: /mnt/testpool/test5: Permission denied COMMENT: LET'S GIVE THE UNPRIVILEGED ACCOUNT 'ra' INSTEAD OF 'r'. COMMENT: WITH "ra" IT CAN READ THE DIR AGAIN: # setfacl -a 0 everyone@:ra::allow /mnt/testpool/test5 ; getfacl /mnt/testpool/test5 # file: /mnt/testpool/test5 # owner: root # group: wheel everyone@:r-----a-------:-------:allow everyone@:r-------------:-------:allow group:nogroup:rwxpDda-R-c---:fd-----:allow owner@:--------------:-------:allow group@:--------------:-------:allow everyone@:--------------:-------:allow % ls /mnt/testpool/test5 subdir subfile COMMENT: CONFIRM THE "a" WAS NECESSARY, BY REMOVING IT. COMMENT: THE UNPRIVILEGED ACCOUNT CAN NOT READ THE DIR WITHOUT "ra": # setfacl -x 0 /mnt/testpool/test5 ; getfacl /mnt/testpool/test5 # file: /mnt/testpool/test5 # owner: root # group: wheel everyone@:r-------------:-------:allow group:nogroup:rwxpDda-R-c---:fd-----:allow owner@:--------------:-------:allow group@:--------------:-------:allow everyone@:--------------:-------:allow % ls /mnt/testpool/test5 ls: /mnt/testpool/test5: Permission denied
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAFwhr76cHm7tLnHAKdvvLhHxFOg0BKQNbfai61pxvNF-NSbzHw>