Can't Write to Samba Share

Question

I've a Raspberry Pi acting as a NAS server. It correctly mounts my drive and shares it through Samba, however, even though I can connect to the share and read stuff, I can't write anything to the drive via the Samba share.

I'm assuming it's a permission issue but I couldn't handle it. Here are the related permissions and my Samba config for my mount.

ls -al /media:

total 37
drwxr-xr-x  12 root   root   4096 Dec  9 20:59 .
drwxr-xr-x  23 root   root   4096 Nov 30 11:03 ..
drwxrwxr-x   1 root   root     25 Dec  9 21:48 HDD
drwxr-x---+  2 root   root   4096 Oct 15 13:38 pi
drwxrwxr-x   1 root   root     25 Dec  9 21:48 usb0
drwxr-xr-x   2 archie archie  512 Jan  1  1970 usb1
drwxr-xr-x   2 root   root   4096 Nov 12 15:18 usb2
drwxr-xr-x   2 root   root   4096 Nov 12 15:18 usb3
drwxr-xr-x   2 root   root   4096 Nov 12 15:18 usb4
drwxr-xr-x   2 root   root   4096 Nov 12 15:18 usb5
drwxr-xr-x   2 root   root   4096 Nov 12 15:18 usb6
drwxr-xr-x   2 root   root   4096 Nov 12 15:18 usb7
lrwxrwxrwx   1 root   root      4 Nov 12 15:18 usb -> usb0

ls -al /media/HDD(my mounted disk):

total 52658332
drwxrwxr-x  1 root root          25 Dec  9 21:48 .
drwxr-xr-x 12 root root        4096 Dec  9 20:59 ..
drwxrwxrwx  1   99   99           9 Dec 19  2016 Apple
drwxrwxrwx  1   99   99          37 Sep  6 08:20 Archive
drwxrwxrwx  1   99   99           4 May  1  2017 Development
d--x--x--x  1   99   99           8 Oct 21 06:48 .DocumentRevisions-V100
drwxrwxrwx  1   99   99          45 Oct 12 18:24 Films
drwxrwxrwx  1   99   99          16 May  3  2016 Fitness
drwx------  1   99   99         119 Oct 21 06:49 .fseventsd
dr-xr-xr-t  1 root root           2 Dec 23  2017 .HFS+ Private Directory Data?
drwxrwxrwx  1   99   99          13 Oct 20 18:01 iTunes
drwxrwxrwx  1   99   99          12 Sep  7 10:34 Other
drwxrwxrwx  1   99   99           8 Sep  6 08:17 Photos
drwx------  1   99   99           5 Dec 23  2017 .Spotlight-V100
d-wx-wx-wt  1   99   99           3 Sep  6 10:27 .TemporaryItems
d-wx-wx-wt  1   99   99           4 Oct 12 18:24 .Trashes
drwxrwxrwx  1   99   99          10 Sep 11  2017 Tutorials
drwxrwxrwx  1   99   99          13 Oct  4 17:42 TV Shows
drwxrwxrwx  1   99   99           9 Sep 29 17:07 Videos
-rw-r--r--  1   99   99 53687213568 Oct 15 08:08 .cache.dmg
-rw-r--r--  1   99   99           0 Sep  7 08:49 .com.apple.timemachine.donotpresent
-rw-r--r--  1   99   99       22532 Oct 21 06:48 .DS_Store
----------  1 root root   234881024 Dec 23  2017 .journal
----------  1 root root        8192 Dec 23  2017 .journal_info_block

/etc/samba/smb.conf:

[NAS]
comment = NAS Folder
path = /media/HDD
valid users = @users
force group = users
create mask = 0775
directory mask = 0775
read only = no
force user = walter

Answer 1

It looks like you have the mount permissions as read/write for root but only read for anyone else. I think you would need to set the permissions on /media/HDD to be writeable for the walter user or the users group.

sudo chown -R root:users /media/HDD will set the group permissions to users (I presume this exists?) or sudo chown -R walter:users /media/HDD will make it owned by walter.