Re: [Powertop] [PATCH 1/2] perf_bundle: Check memory allocation failure
On 9/18/2012 7:21 AM, Namhyung Kim wrote:
Check return value of malloc/strdup not to make NULL dereferences.
I don't mind these patches; they are clean code
however, one of the core userspace developers at work basically said "we don't
check for malloc NULL in userspace;
if that ever happens the system is so screwed up anyway that you just cannot
continue".
Signed-off-by: Namhyung Kim <namhyung(a)gmail.com>
---
src/perf/perf_bundle.cpp | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/src/perf/perf_bundle.cpp b/src/perf/perf_bundle.cpp
index 38e1e91..4e70f30 100644
--- a/src/perf/perf_bundle.cpp
+++ b/src/perf/perf_bundle.cpp
@@ -60,6 +60,9 @@ void perf_bundle_event::handle_event(struct perf_event_header *header,
void *coo
vector<void *> *vector;
buffer = (unsigned char *)malloc(header->size);
+ if (!buffer)
+ return;
+
memcpy(buffer, header, header->size);
#ifdef USE_DECLTYPE
@@ -130,6 +133,9 @@ static void parse_event_format(const char *event_name)
{
char *tptr;
char *name = strdup(event_name);
+ if (!name)
+ return;
+
char *sys = strtok_r(name, ":", &tptr);
char *event = strtok_r(NULL, ":", &tptr);
char *file;
@@ -137,6 +143,9 @@ static void parse_event_format(const char *event_name)
file = (char *)malloc(strlen(sys) + strlen(event) +
strlen("/sys/kernel/debug/tracing/events////format") + 2);
+ if (!file)
+ return;
+
sprintf(file, "/sys/kernel/debug/tracing/events/%s/%s/format", sys, event);
buf = read_file(file);
@@ -169,6 +178,10 @@ bool perf_bundle::add_event(const char *event_name)
if ((int)ev->trace_type >= 0) {
if (event_names.find(ev->trace_type) == event_names.end()) {
event_names[ev->trace_type] = strdup(event_name);
+ if (!event_names[ev->trace_type]) {
+ delete ev;
+ continue;
+ }
parse_event_format(event_name);
}
events.push_back(ev);