Suppose I have a folder, containing other files and folders, and I'd like to find out recursively which subfiles and subfolders have non-default permissions (i.e., not 644 or 755).
Which command can be used to do that? The command should output a list of the relevant files and folders, and their permissions.
You can do the entire task using just find:
$ find . -type f ! \( -perm 755 -o -perm 644 \) -printf "%m\t%p\n"
Make all permutations of permissions (000-777).
$ touch {0..7}{0..7}{0..7}
$ for i in {0..7}{0..7}{0..7}; do chmod $i $i;done
$ find . -type f | wc -l
512
A sample of our find command's list of files it's finding:
$ find . -type f ! \( -perm 755 -o -perm 644 \) -printf "%m\t%p\n"| head -10
734 ./734
376 ./376
555 ./555
663 ./663
256 ./256
336 ./336
2 ./002
152 ./152
527 ./527
416 ./416
If we run our find command we can confirm that it worked:
$ find . -type f ! \( -perm 755 -o -perm 644 \) -printf "%m\t%p\n" | grep 755
$ find . -type f ! \( -perm 755 -o -perm 644 \) -printf "%m\t%p\n" | grep 644
find implementation treated -perm 755 as -perm 01363, or a chmod implementation treated chmod 755 as chmod 01362, you'd think someone would have noticed by now and reported it as a bug. Note that there is only one implementation of find that supports -printf.
find(1), but elsewhere... I got into the habit of making octal for file permissions explicit when I got bitten by decimal (decades ago, don't remember much details).
find . \( \
-type d ! -perm 755 -o \
-type l ! -perm 777 -o \
-type f ! \( -perm 644 -o -perm 755 \) -o \
! -type f ! -type l ! -type d ! -perm 644 \) -exec ls -ld {} +
find . -printf "%m\t%p\n" | grep -Ev "^(755|644)"
Example output:
$ find . -printf "%m\t%p\n" | grep -Ev "^(755|644)"
777 ./a/writable/folder
777 ./another/folder
666 ./an/executable-file
Please note that the egrep command does not consider whether a line is a file or folder. As a result, files with permission 755 and folders with permission 644 would not be found by this command.
Furthermore this command is not very efficient, as find starts by printing all subfolders and subfiles, and only after that the files and folders are filtered by egrep. However, I haven't found a better method yet.
-r-sr-s--T (7550). egrep and find concurrently, there's no efficiency issue here.