On 11.09.2013 09:22, Mark Tinguely wrote: > On 09/11/13 08:55, Christoph Hellwig wrote: > >On Tue, Sep 10, 2013 at 01:47:20PM -0500, Mark Tinguely wrote: > >>This patch allows clients like DMF to modify an immutable file > >>without changing the immutable capability on the file, which > >>would expose the file to change. > >> > >>This patch is restricted to holders of the CAP_LINUX_IMMUTABLE, > >>so no addition security risk has been introduced. > > > >The immutable flag means that the file can't be modified, and > >CAP_LINUX_IMMUTABLE allows setting/removing that restriction, but not > >ignoring it. > > > >So: NAK, this is a change in semantics and long-standing behaviour. > > > > As you said, the CAP_LINUX_IMMUTABLE allows the holder of the > capability to turn on/off the restriction. The holder of > CAP_LINUX_IMMUTABLE could turn off immutability, modify it and then > turn it back on, but during that window, others could modify it too > which may be more undesirable than changing the behavior. It's like setting a file you own "444" only because you CAN set it to 666 doesn't mean that the check should be short-circuted. $ touch test $ chmod 444 test $ echo 'Hallo' > test -bash: test: Permission denied -- Matthias _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
