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    In message <11900.974244463@ocs3.ocs-net> you write:
    > On 14 Nov 2000 11:42:42 -0800,
    > "H. Peter Anvin" <hpa@zytor.com> wrote:
    > >Seriously, though, I don't see any reason modprobe shouldn't accept
    > >funky filenames. There is a standard way to do that, which is to have
    > >an argument consisting of the string "--"; this indicates that any
    > >further arguments should be considered filenames and not options.
    >
    > The original exploit had nothing to do with filenames masquerading as
    > options, it was: ping6 -I ';chmod o+w .'. Then somebody pointed out
    > that -I '-C/my/config/file' could be abused as well. '--' fixes the
    > second exploit but not the first.

    Yes, modprobe code is stupid (execing insmod without "--"). Of
    course, the passing of flags to modprobe is pretty broken too (the
    kernel shouldn't assume anything about modprobe, otherwise why bother
    with the /proc entry?)

    But the kernel should be fixed for future:

    --- working-2.4.0-test11-5/kernel/kmod.c.~1~ Wed Oct 4 15:17:12 2000
    +++ working-2.4.0-test11-5/kernel/kmod.c Fri Nov 17 11:44:09 2000
    @@ -133,7 +133,7 @@
    static int exec_modprobe(void * module_name)
    {
    static char * envp[] = { "HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
    - char *argv[] = { modprobe_path, "-s", "-k", (char*)module_name, NULL };
    + char *argv[] = { modprobe_path, "-s", "-k", "--", (char*)module_name, NULL };
    int ret;

    ret = exec_usermodehelper(modprobe_path, argv, envp);
    --
    Hacking time.
    -
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