Not able to give write permission to other user with ACL or chmod

Anyone know why rocky can't write to /tmp/afile? Giving rocky permission as an other user with chmod o+w doesn't seem to work either 🤔 I updated the acl with: setfacl -m u:rocky:rw /tmp/afile id as rocky and owner: > rocky@jammy:~$ id > uid=1001(rocky) gid=1001(rocky) groups=1001(rocky) > seb@jammy:~$ id > uid=1000(seb) gid=1000(seb) groups=1000(seb),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),122(lpadmin),134(lxd),135(sambashare) ls -ld output > seb@jammy:~$ ls -ld /tmp/afile > -rw-rw-rw-+ 1 seb seb 0 Jul 3 14:25 /tmp/afile Owner is able to write without issue: > seb@jammy:~$ echo rounders > /tmp/afile > seb@jammy:~$ cat /tmp/afile > rounders getfacl -n output: > seb@jammy:~$ getfacl -n /tmp/afile getfacl: Removing leading '/' from > absolute path names > # file: tmp/afile > # owner: 1000 > # group: 1000 > user::rw- > user:1001:rw- > group::rw- > mask::rw- > other::rw- df -T and mount output: > seb@jammy:~$ df -T /tmp > Filesystem Type 1K-blocks Used Available Use% Mounted on > /dev/sda2 ext4 120044288 18487840 95412296 17% / > seb@jammy:~$ mount | grep /dev/sda2 > /dev/sda2 on / type ext4 (rw,relatime,errors=remount-ro) > /dev/sda2 on /var/snap/firefox/common/host-hunspell type ext4 (ro,noexec,noatime,errors=remount-ro) Attempt to write to file as rocky: seb@jammy:~$ getfacl /tmp/afile getfacl: Removing leading '/' from absolute path names # file: tmp/afile # owner: seb # group: seb user::rw- user:rocky:rw- group::rw- mask::rw- other::rw- seb@jammy:~$ su - rocky #Password: rocky@jammy:~$ echo hello > /tmp/afile -bash: /tmp/afile: Permission denied