James,

You asked on bugtraq:

> GNU find does a sanity check before and after calling chdir(). It
> stats the directory it's about to move into, and stats "." after
> chdir() succeeds. It then compares the device numbers and inode
> numbers returned by he two stat() calls. This is done in a function
> called wd_sanity_check(). If these are different, find prints an
> error and exits fatally (in versions up to and including GNU findutils
> 4.2.5.
> ...
> [ Shenanigans with automounter upset wd_sanity_check() ]
> As of findutils 4.2.6/4.2.7, find will read /etc/mtab ...
> [ Shenanigans in Solaris automounter upset mtab check ]
> ... Hence my question is :-
> Is it worthwhile at all to perform this "sanity check" or is it of
> insufficient benefit?
> I'd be grateful for your thoughts.

What I would like to see implemented (in some messy pseudo-code, starting
in parent directory):

PARENT=stat(".");
SUBDIR=stat("subdir");
chdir("subdir");
DOT=stat(".");
if (SUBDIR != DOT) {
Print warning message
}
else {
Go on with find (recurse)
}
chdir("..");
DOT=stat(".");
if (PARENT != DOT) {
Print message
Exit with fatal error
}

Do not descend into "dodgy" directories, but back out of them; exit fatally
if you cannot get back to solid ground.

Is this doable?

Cheers,

Paul Szabo - psz (at) maths.usyd.edu (dot) au [email concealed] http://www.maths.usyd.edu.au:8000/u/psz/
School of Mathematics and Statistics University of Sydney 2006 Australia

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