noexec option enabled in fstab is not getting applicable for limited user. Is it a bug?
cat /etc/fstab
# / was on /dev/sda2 during installation
UUID=fd7e2645-3cc4-4c6c-8b1b-016711c2fd07 / ext4 errors=remount-ro 0 1
# /boot was on /dev/sda1 during installation
UUID=f3e58f86-8999-4678-a5ec-0a4b621c6e37 /boot ext4 defaults 0 2
# /home was on /dev/sda9 during installation
UUID=bcbc1c4d-46a9-4b2a-bb0a-6fe1bdeaed22 /home ext4 defaults,nodev,nosuid 0 2
# /tmp was on /dev/sda5 during installation
UUID=8538eecc-bd16-40fe-ad66-7d7b9287839e /tmp ext4 defaults,noexec,nosuid,nodev 0 2
# /var was on /dev/sda6 during installation
UUID=292696cf-fc15-40ab-9cd8-cee9bff7e165 /var ext4 defaults,nosuid,nodev 0 2
# /var/log was on /dev/sda7 during installation
UUID=fab1f85b-ae09-4ce0-b169-c01205eb8f9c /var/log ext4 defaults,noexec,nosuid,nodev 0 2
# /var/log/audit was on /dev/sda8 during installation
UUID=602f5003-4ac0-49e9-99d3-b29378ce9430 /var/log/audit ext4 defaults,noexec,nosuid,nodev 0 2
# swap was on /dev/sda3 during installation
UUID=a538d35b-b2e9-47f2-b72d-5dbbcf0afca0 none swap sw 0 0
/dev/sdb1 /mnt/usblpsc auto noauto,user,rw,noexec,nosuid,nodev 0 0
/dev/sdc1 /mnt/usblpsc auto noauto,user,rw,noexec,nosuid,nodev 0 0
/dev/sdd1 /mnt/usblpsc auto noauto,user,rw,noexec,nosuid,nodev 0 0
sudo users are not able to paste executable files in /bin into the file system which have the noexec option set. But limited users are able to paste the same files into the file system which have noexec option set. Why is it so?