[PATCH 12/16] perf evlist: Validate that mmap_pages is not too big

From: Arnaldo Carvalho de Melo
Date: Wed Oct 23 2013 - 16:59:35 EST


From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

Amend perf_evlist__parse_mmap_pages() to check that the mmap_pages
entered via the --mmap_pages/-m option is not too big.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1382427258-17495-15-git-send-email-adrian.hunter@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/evlist.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 85c4c80bcac8..2ce92eceb424 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -698,7 +698,8 @@ static size_t perf_evlist__mmap_size(unsigned long pages)
int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
int unset __maybe_unused)
{
- unsigned int pages, val, *mmap_pages = opt->value;
+ unsigned int *mmap_pages = opt->value;
+ unsigned long pages, val;
size_t size;
static struct parse_tag tags[] = {
{ .tag = 'B', .mult = 1 },
@@ -709,12 +710,12 @@ int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
};

val = parse_tag_value(str, tags);
- if (val != (unsigned int) -1) {
+ if (val != (unsigned long) -1) {
/* we got file size value */
pages = PERF_ALIGN(val, page_size) / page_size;
- if (!is_power_of_2(pages)) {
+ if (pages < (1UL << 31) && !is_power_of_2(pages)) {
pages = next_pow2(pages);
- pr_info("rounding mmap pages size to %u (%u pages)\n",
+ pr_info("rounding mmap pages size to %lu (%lu pages)\n",
pages * page_size, pages);
}
} else {
@@ -727,6 +728,11 @@ int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
}
}

+ if (pages > UINT_MAX || pages > SIZE_MAX / page_size) {
+ pr_err("--mmap_pages/-m value too big\n");
+ return -1;
+ }
+
size = perf_evlist__mmap_size(pages);
if (!size) {
pr_err("--mmap_pages/-m value must be a power of two.");
--
1.8.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/