| Date | Thu, 6 Aug 2015 16:50:40 -0300 | From | Arnaldo Carvalho de Melo <> | Subject | Re: [PATCH V8 15/25] perf tools: Validate config term maximum value |
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Em Fri, Jul 17, 2015 at 07:33:50PM +0300, Adrian Hunter escreveu: > Currently the value of a PMU config term is silently > truncated if it is too big. This is an impediment to > validating the value for other criteria later on i.e. > the user provides an invalid value that gets truncated > to a valid one.
Applied
> The maximum value validation is only done for the > parser where the error is passed back to the user. In > other cases the silent truncation continues so as not > to affect tools that perhaps rely on it. > > Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> > --- > tools/perf/util/pmu.c | 30 +++++++++++++++++++++++++++++- > 1 file changed, 29 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c > index d26ff0ab8410..29797fd9bedc 100644 > --- a/tools/perf/util/pmu.c > +++ b/tools/perf/util/pmu.c > @@ -585,6 +585,18 @@ static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v, > } > } > > +static __u64 pmu_format_max_value(const unsigned long *format) > +{ > + int w; > + > + w = bitmap_weight(format, PERF_PMU_FORMAT_BITS); > + if (!w) > + return 0; > + if (w < 64) > + return (1ULL << w) - 1; > + return -1; > +} > + > /* > * Term is a string term, and might be a param-term. Try to look up it's value > * in the remaining terms. > @@ -658,7 +670,7 @@ static int pmu_config_term(struct list_head *formats, > { > struct perf_pmu_format *format; > __u64 *vp; > - __u64 val; > + __u64 val, max_val; > > /* > * If this is a parameter we've already used for parameterized-eval, > @@ -724,6 +736,22 @@ static int pmu_config_term(struct list_head *formats, > } else > return -EINVAL; > > + max_val = pmu_format_max_value(format->bits); > + if (val > max_val) { > + if (err) { > + err->idx = term->err_val; > + if (asprintf(&err->str, > + "value too big for format, maximum is %llu", > + (unsigned long long)max_val) < 0) > + err->str = strdup("value too big for format"); > + return -EINVAL; > + } > + /* > + * Assume we don't care if !err, in which case the value will be > + * silently truncated. > + */ > + } > + > pmu_format_value(format->bits, val, vp, zero); > return 0; > } > -- > 1.9.1
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