linux - partition being mounted as noexec, not fstab, what else can it be?

I have one partition being mounted as noexec. It shows on the mount output, but there is nothing on fstab to do that.

Where is the noexec coming from?

my fstab:

UUID=1fbb29fe-cef2-4cc2-9b1e-ac45e74289ac /               ext4    noatime,nodiratime,errors=remount-ro 0       1
# swap was on /dev/sda3 during installation
UUID=some-uuid-string none            swap    sw              0       0
/dev/sr0        /media/cdrom0   udf,iso9660 user,noauto     0       0

tmpfs   /tmp         tmpfs   nodev,nosuid,noexec,size=2G          0  0

# old disks
#/dev/md0     /DATA  ext4   noauto,nodiratime,errors=remount-ro,user 0 2
# new disks:
/dev/md1     /DATA  ext4   noauto,nodiratime,errors=remount-ro,user 0 2

I mount the /DATA partition above as either a user or root. In either case I get:

/dev/md1 on /DATA type ext4 (rw,nosuid,nodev,noexec,nodiratime,relatime,errors=remount-ro,stripe=16384,data=ordered,user)

Answer

The default is indeed exec, but using the user option implies the following options:

• noexec


• nosuid


• nodev

As explained in man mount:

   user   Allow an ordinary user to mount the filesystem.  The name of the
          mounting user is written to the mtab file  (or  to  the  private
          libmount  file  in /run/mount on systems without a regular mtab)
          so that this same user can unmount the filesystem  again.   This
          option  implies  the  options  noexec, nosuid, and nodev (unless
          overridden  by  subsequent  options,  as  in  the  option   line
          user,exec,dev,suid).