CVS commit: src/lib/librumphijack

["Antti Kantee" <pooka%netbsd.org@localhost>]

Module Name:    src
Committed By:   pooka
Date:           Thu Feb 17 15:20:10 UTC 2011

Modified Files:
        src/lib/librumphijack: hijack.c

Log Message:
In case dup2(n, n+FDOFF) is done, the caller thinks there are two
distinct file descriptors, but the rump kernel thinks they are both
the same.  Now, if either one is closed by the application, "both"
will be closed in the rump kernel.  To fix this, maintain an
alias-mask.  It's not a perfect solution, though (consider e.g.
F_SETFL).  Maybe we should actually dup the fd and maintain a
mapping table?

Also, prevent the host from opening file descriptors onto the places
in the fd namespace that have been dupped.

These together fix "cat < /rump/foo" in a hijacked /bin/sh.
(the first one makes sure stdin is open in cat and the second one
makes sure it doesn't try to cat something from /usr/share/locale
instead of stdin)


To generate a diff of this commit:
cvs rdiff -u -r1.46 -r1.47 src/lib/librumphijack/hijack.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.