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I have a folder that I'm mounting via /etc/fstab with an entry like this:

/m/svr/usrlocal/bin     /usr/local/bin2     none exec,bind 0 0

When I mount this folder, syslog produces no error message or comment, and the folder is mounted, as can be seen by findmnt --real:

> findmnt --real|grep usr.local.bin2
├─/usr/local/bin2              /dev/sda2[/svr/usrlocal/bin]     fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096

The problem I have, is that, as can be seen above, the folder is mounted with "noexec" permissions, in spite of my specifying exec on the fstab line. I have tried this with 'exec,defaults' and defaults (without specifying exec) and several other combinations, but to no avail. No error message, but I also don't get what I want. (/usr/local/bin2/scriptname always returns access denied error.)

Is there a way, with bind mount on ubuntu 20.04, to mount a folder with execute permissions?

ADDITIONAL INFORMATION

The directory to which I'm mounting, is in the root filesystem of the server. Its permissions are already set to drwxrwxr-x

When I add remount to the options as in the following, I get this error when trying to mount: "mount: /usr/local/bin2: mount point not mounted or bad option."

/m/svr/usrlocal/bin     /usr/local/bin2    none remount,exec,bind 0 0

Here is the full output of "mount" without options:

sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,noexec,relatime,size=32827460k,nr_inodes=8206865,mode=755,inode64)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=6572748k,mode=755,inode64)
/dev/sdc2 on / type ext4 (rw,relatime,errors=remount-ro)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,inode64)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k,inode64)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,mode=755,inode64)
cgroup2 on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
efivarfs on /sys/firmware/efi/efivars type efivarfs (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/misc type cgroup (rw,nosuid,nodev,noexec,relatime,misc)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=28,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=13971)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
/var/lib/snapd/snaps/bare_5.snap on /snap/bare/5 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-38-2004_115.snap on /snap/gnome-3-38-2004/115 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/vlc_3078.snap on /snap/vlc/3078 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/core18_2679.snap on /snap/core18/2679 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/core18_2697.snap on /snap/core18/2697 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-38-2004_119.snap on /snap/gnome-3-38-2004/119 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-34-1804_77.snap on /snap/gnome-3-34-1804/77 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/core20_1778.snap on /snap/core20/1778 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/gtk-common-themes_1534.snap on /snap/gtk-common-themes/1534 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/core20_1822.snap on /snap/core20/1822 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/vlc_2344.snap on /snap/vlc/2344 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/snap-store_638.snap on /snap/snap-store/638 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/snapd_17950.snap on /snap/snapd/17950 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/snap-store_599.snap on /snap/snap-store/599 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/snapd_18357.snap on /snap/snapd/18357 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/gtk-common-themes_1535.snap on /snap/gtk-common-themes/1535 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-34-1804_72.snap on /snap/gnome-3-34-1804/72 type squashfs (ro,nodev,relatime,errors=continue,x-gdu.hide)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,nosuid,nodev,noexec,relatime)
/dev/sdb1 on /v type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096,user)
/dev/sdc1 on /boot/efi type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
/dev/sda2 on /m type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096,user)
/dev/sda2 on /usr/local/backups type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
/dev/sda2 on /usr/local/etc type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
/dev/sda2 on /usr/local/log type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
/dev/sda2 on /usr/local/src type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096)
/dev/sdd2 on /5TBU type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096,user)
//nas-1/NAS1-Plex on /m/svr/Media/Plex_NAS1 type cifs (rw,nosuid,nodev,noexec,relatime,vers=3.0,sec=ntlmssp,cache=strict,username=dennis,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.1.7,file_mode=0755,dir_mode=0755,soft,nounix,serverino,mapposix,noperm,rsize=4194304,wsize=4194304,bsize=1048576,echo_interval=60,actimeo=1,user)
tmpfs on /run/user/125 type tmpfs (rw,nosuid,nodev,relatime,size=6572744k,mode=700,uid=125,gid=130,inode64)
gvfsd-fuse on /run/user/125/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=125,group_id=130)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=6572744k,mode=700,uid=1000,gid=1000,inode64)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
//hpmicro1/share on /o type cifs (rw,nosuid,nodev,noexec,relatime,vers=3.0,sec=ntlmssp,cache=strict,username=dennis,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.1.5,file_mode=0755,dir_mode=0755,soft,nounix,serverino,mapposix,noperm,rsize=4194304,wsize=4194304,bsize=1048576,echo_interval=60,actimeo=1,user)
/dev/sda2 on /usr/local/bin2 type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096)

Here is the output of findmnt --real

> findmnt --real
TARGET                         SOURCE            FSTYPE   OPTIONS
/                              /dev/sdc2         ext4     rw,relatime,errors=remount-ro
├─/sys/kernel/tracing          tracefs           tracefs  rw,nosuid,nodev,noexec,relatime
├─/snap/bare/5                 /dev/loop0        squashfs ro,nodev,relatime,errors=continue
├─/snap/gnome-3-38-2004/115    /dev/loop2        squashfs ro,nodev,relatime,errors=continue
├─/snap/vlc/3078               /dev/loop3        squashfs ro,nodev,relatime,errors=continue
├─/snap/core18/2679            /dev/loop1        squashfs ro,nodev,relatime,errors=continue
├─/snap/core18/2697            /dev/loop4        squashfs ro,nodev,relatime,errors=continue
├─/snap/gnome-3-38-2004/119    /dev/loop5        squashfs ro,nodev,relatime,errors=continue
├─/snap/gnome-3-34-1804/77     /dev/loop6        squashfs ro,nodev,relatime,errors=continue
├─/snap/core20/1778            /dev/loop10       squashfs ro,nodev,relatime,errors=continue
├─/snap/gtk-common-themes/1534 /dev/loop8        squashfs ro,nodev,relatime,errors=continue
├─/snap/core20/1822            /dev/loop11       squashfs ro,nodev,relatime,errors=continue
├─/snap/vlc/2344               /dev/loop9        squashfs ro,nodev,relatime,errors=continue
├─/snap/snap-store/638         /dev/loop7        squashfs ro,nodev,relatime,errors=continue
├─/snap/snapd/17950            /dev/loop12       squashfs ro,nodev,relatime,errors=continue
├─/snap/snap-store/599         /dev/loop14       squashfs ro,nodev,relatime,errors=continue
├─/snap/snapd/18357            /dev/loop15       squashfs ro,nodev,relatime,errors=continue
├─/snap/gtk-common-themes/1535 /dev/loop13       squashfs ro,nodev,relatime,errors=continue
├─/snap/gnome-3-34-1804/72     /dev/loop16       squashfs ro,nodev,relatime,errors=continue
├─/v                           /dev/sdb1         fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
├─/boot/efi                    /dev/sdc1         vfat     rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro
├─/m                           /dev/sda2         fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
│ └─/m/svr/Media/Plex_NAS1     //nas-1/NAS1-Plex cifs     rw,nosuid,nodev,noexec,relatime,vers=3.0,sec=ntlmssp,cache=strict,username=dennis,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.1.7,file_mode=0755,dir
├─/usr/local/backups           /dev/sda2[/svr/usrlocal/backups]
│                                                fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
├─/o                           //hpmicro1/share  cifs     rw,nosuid,nodev,noexec,relatime,vers=3.0,sec=ntlmssp,cache=strict,username=dennis,uid=0,noforceuid,gid=0,noforcegid,addr=192.168.1.5,file_mode=0755,dir                                             
├─/usr/local/etc               /dev/sda2[/svr/usrlocal/etc]
│                                                fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
├─/usr/local/log               /dev/sda2[/svr/usrlocal/log]
│                                                fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
├─/usr/local/src               /dev/sda2[/svr/usrlocal/src]
│                                                fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
├─/usr/local/bin2              /dev/sda2[/svr/usrlocal/bin]
│                                                fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096
└─/5TBU                        /dev/sdd2         fuseblk  rw,nosuid,nodev,noexec,relatime,user_id=0,group_id=0,allow_other,blksize=4096

~

Improve this question
4
  • What filesystem are you trying to mount? Where are you trying to mount it? What happens if you do chmod 755 <your_directory>?
    – tukan
    Commented Feb 20, 2023 at 8:09
  • Bind mounting silently ignores all options and just uses the source path mount options. Try as a workaround to add the option of remount.
    – harrymc
    Commented Feb 20, 2023 at 9:15
  • Thank you for your responses. I Have updated the question with the results from your suggestions. Still looking for a workable solution.
    – Dennis
    Commented Feb 20, 2023 at 14:01
  • @harrymc please make your comment into an answer (minus the remount bit) and I will accept it. I misread initially, thinking you were saying that I couldn't override the attributes of the mount-point-parent. But you meant that I cannot override the attributes of the mounted-directory-parent, which turns out to be the culprit here. (Can be seen above: /m is mounted with noexec, so anything under /m cannot be mounted with exec.)
    – Dennis
    Commented Feb 20, 2023 at 14:31

1 Answer 1

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+50

This subject is treated in depth in the article Read-only bind mounts.

In short, a mount-point that is partial to a parent cannot override the parent's attributes, so will inherit them from the parent, in effect ignoring all the specified options for the mount-point that conflict with the parent's.

The linked article shows a workaround method when using the bind command, but which does not apply to /etc/fstab.

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  • 1
    Regarding --bind -o ro, it's no longer true with recent kernels. Not sure how recent you need, but it has worked for quite a while AFAIK. (After all, the article is ancient.) But indeed apparently the "workaround" (i.e. -o remount) does apply to the [no]exec case as well. (Interestingly btw, when I just tested, an ro bind mount somehow seems to automatically ignore the noexec on the source. Wonder if that's a bug or some intentional convenience.)
    – Tom Yan
    Commented Feb 20, 2023 at 15:03
  • Excellent, @harrymc! Thank you!
    – Dennis
    Commented Feb 24, 2023 at 1:34
  • Thanks for your additional commentary, @TomYan - very helpful! :)
    – Dennis
    Commented Feb 24, 2023 at 1:37

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