Messages in this thread | | | Date | Tue, 1 Jun 2010 22:45:27 +0100 | From | Al Viro <> | Subject | Re: [PATCH v3] fs: allow protected cross-uid sticky symlinks |
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On Tue, Jun 01, 2010 at 02:07:34PM -0700, Kees Cook wrote: > > I don't buy it. If we are concerned about the symlinks in the middle of > > pathname, your checks are useless (mkdir /tmp/a, ln -s whatever /tmp/a/b, > > have victim open /tmp/a/b/something). If we are not, then your checks are > > in the wrong place. > > Well, that's not traditionally where the problems happen, but I have no > problem strengthening the protection to include a full examination of the > entire path looking for sticky/world-writable directories. > > If not, what is the right place for the checks?
Handling of trailing symlink on open(). At most. And I wouldn't be surprised if the real answer turns out to include "... if we have O_CREAT in flags", but that needs to be determined.
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