I'm confused by permission denied despite apparently having correct permissions to /dev/bus/usb/005/017.This is similar to this question, but I have already tried restarting my ssh session.$ sudo ls -la  /dev/bus/usb/005/total 0drw-rw-rw- 2 root root      120 Dec 25 12:40 .drw-rw-rw- 7 root root      140 Apr 20  2010 ..crw-rw-rw- 1 root root 189, 512 Dec 25 12:20 001crw-rw-rw- 1 root root 189, 515 Dec 25 12:20 004crw-rw-rw- 1 root root 189, 516 Dec 25 12:20 005crw-rw-rw- 1 root adb  189, 528 Dec 25 12:40 017 #adb group, g+rw$ groups ealfonsoealfonso : ealfonso cdrom floppy audio dip video plugdev netdev scanner bluetooth adb # I am in adb group$ ls -la  /dev/bus/usb/005/017ls: cannot access /dev/bus/usb/005/017: Permission denied$ sudo chown ealfonso:ealfonso /dev/bus/usb/005/017 $ sudo ls -l /dev/bus/usb/005/017crw-rw-rw- 1 ealfonso ealfonso 189, 528 Dec 25 12:40 /dev/bus/usb/005/017 #owned by ealfonso$ ls /dev/bus/usb/005/017ls: cannot access /dev/bus/usb/005/017: Permission deniedWhat am I missing?Edit: adding output of ls -ld as requested:$ sudo ls -lad  /dev/bus/usb/005drw-rw-rw- 2 root root 120 Dec 25 12:40 /dev/bus/usb/005 #missing a+x$ sudo chmod a+x /dev/bus/usb/005 # add a+x$ ls -la  /dev/bus/usb/005/017 # still deniedls: cannot access /dev/bus/usb/005/017: Permission denied$ sudo ls -lad  /dev/bus/usb/005drwxrwxrwx 2 root ealfonso 120 Dec 25 12:40 /dev/bus/usb/005Edit. As pointed out in the comments, /dev/bus/usb was also missing x permissions$ ls /dev/bus/usb -lls: cannot access /dev/bus/usb/005: Permission deniedls: cannot access /dev/bus/usb/004: Permission deniedls: cannot access /dev/bus/usb/003: Permission deniedls: cannot access /dev/bus/usb/002: Permission deniedls: cannot access /dev/bus/usb/001: Permission deniedtotal 0d????????? ? ? ? ?            ? 001d????????? ? ? ? ?            ? 002d????????? ? ? ? ?            ? 003d????????? ? ? ? ?            ? 004d????????? ? ? ? ?            ? 005$ sudo ls /dev/bus/usb -ltotal 0drw-rw-rw- 2 root root      60 Apr 20  2010 001drw-rw-rw- 2 root root      80 Apr 20  2010 002drw-rw-rw- 2 root root      60 Apr 20  2010 003drw-rw-rw- 2 root root      60 Apr 20  2010 004drwxrwxrwx 2 root ealfonso 120 Dec 25 12:40 005$ sudo chmod a+x /dev/bus/usb $ ls -la  /dev/bus/usb/005/017crw-rw-rw- 1 root ealfonso 189, 528 Dec 25 13:43 /dev/bus/usb/005/017
permission denied /dev/bus/usb/
permissions;usb;udev;chmod;permission denied
Here's part of your output:ls -la  /dev/bus/usb/005/017ls: cannot access /dev/bus/usb/005/017: Permission deniedHint: you can always stat a file as long as you can get to it (via the directory that contains it), even if you don't have permission to it. So with this, I suspected that your problem was not actually with /dev/bus/usb/005/017 itself.Getting access to the file in order to be able to stat it is a matter of having x (execute) access to all the directories in the pathname. That is,//dev/dev/bus/dev/bus/usb/dev/bus/usb/005One or more of those directories must be missing x permission. But probably not / or /dev as your system would probably be unusable if the problem lay there. Note that any or all of those directories may have r access, allowing you to see what files they contain but not get at those files.Why were your /dev/bus/usb/005 and /dev/bus/usb missing x permission?Those directories will have been created when udev first created the device nodes and their parent directories. Perhaps the umask on the udev daemon is too strict? I'm not really sure why that would be on your system. For correct operation, none of the octal digits in the umask should be odd. Note that the problem might be with the udevd started at early boot time in the initramfs.