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    SubjectRe: [PATCH 6/8] ASoC: intel: skylake: change snprintf to scnprintf for possible overflow
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    >> diff --git a/sound/soc/intel/skylake/skl-debug.c b/sound/soc/intel/skylake/skl-debug.c
    >> index 5d7ac2ee7a3c..bb28db734fb7 100644
    >> --- a/sound/soc/intel/skylake/skl-debug.c
    >> +++ b/sound/soc/intel/skylake/skl-debug.c
    >> @@ -43,7 +43,7 @@ static ssize_t skl_print_pins(struct skl_module_pin *m_pin, char *buf,
    >> ssize_t ret = 0;
    >>
    >> for (i = 0; i < max_pin; i++)
    >> - ret += snprintf(buf + size, MOD_BUF - size,
    >> + ret += scnprintf(buf + size, MOD_BUF - size,
    >> "%s %d\n\tModule %d\n\tInstance %d\n\t"
    >> "In-used %s\n\tType %s\n"
    >> "\tState %d\n\tIndex %d\n",
    >>
    > While working on a Coccinelle script to find more cases of this, I
    > noticed that this code is buggy: it keeps overwriting the same
    > position in the buf string: "buf + size" and don't take "ret" into
    > account at all. This needs to be:
    >
    > ret += scnprintf(buf + size + ret, MOD_BUF - size - ret,

    Thanks for the sighting. Indeed this looks like a bug, all other calls
    to snprintf use "ret" to modify the destination/length.

    The only explanation I have for it not being noticed earlier is that
    it's possibly not used - a 5mn test on 2 machines show the loop is
    actually not run (max_pin == 0).

    It'll take me a bit of time to figure out what exactly this routine is
    supposed to do, maybe we should do the cross-tree change first?

    -Pierre

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