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    SubjectRe: [PATCH] Open Firmware device tree virtual filesystem
    I made all the changes Pekka suggested, except:

    > + security = strncmp(propname, "security-", 9) == 0;
    >> + len = 0;
    > Redundant assignment, no?
    >> + if (!security)
    >> + (void)callofw("getproplen", 2, 1, node,
    >> propname, &len);
    That assignment turns out not to be redundant. If a security variable
    is recognized, you want the length to be 0 so as not to expose the
    password. In that case the following "getproplen" call won't be executed.

    That logic was adapted from the existing file fs/proc/devtree.c . It
    turns out that the code there has a bug: You really want to look for
    just "security-password" ; there is no need to, and good reasons not to,
    suppress the length of "security-mode" and "security-#badlogins". (Good
    OFW implementations won't leak the password length anyway, so check is
    only needed as a workaround).

    I have rewritten the code for clarity and correctness thusly:

    if (strcmp(propname, "security-password") == 0) {
    len = 0; /* Don't leak password length */
    } else {
    callofw("getproplen", 2, 1, node, propname, &len);

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      Last update: 2006-12-31 19:59    [W:0.020 / U:5.352 seconds]
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