perf probe: Remove xzalloc() from util/probe-{event, finder}.c

Remove all xzalloc() calls from util/probe-{event,finder}.c since
it may cause 'sudden death' in utility functions and it makes
reusing it from other code difficult.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171749.3790.33303.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index bd68f7b..aacbf73 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -556,7 +556,9 @@
 	fieldp = &arg->field;
 
 	do {
-		*fieldp = xzalloc(sizeof(struct perf_probe_arg_field));
+		*fieldp = zalloc(sizeof(struct perf_probe_arg_field));
+		if (*fieldp == NULL)
+			return -ENOMEM;
 		if (*tmp == '.') {
 			str = tmp + 1;
 			(*fieldp)->ref = false;
@@ -608,7 +610,11 @@
 
 	/* Copy arguments and ensure return probe has no C argument */
 	pev->nargs = argc - 1;
-	pev->args = xzalloc(sizeof(struct perf_probe_arg) * pev->nargs);
+	pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
+	if (pev->args == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
 	for (i = 0; i < pev->nargs && ret >= 0; i++) {
 		ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
 		if (ret >= 0 &&
@@ -680,7 +686,11 @@
 		tp->offset = 0;
 
 	tev->nargs = argc - 2;
-	tev->args = xzalloc(sizeof(struct kprobe_trace_arg) * tev->nargs);
+	tev->args = zalloc(sizeof(struct kprobe_trace_arg) * tev->nargs);
+	if (tev->args == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
 	for (i = 0; i < tev->nargs; i++) {
 		p = strchr(argv[i + 2], '=');
 		if (p)	/* We don't need which register is assigned. */
@@ -745,7 +755,11 @@
 	char offs[32] = "", line[32] = "", file[32] = "";
 	int ret, len;
 
-	buf = xzalloc(MAX_CMDLEN);
+	buf = zalloc(MAX_CMDLEN);
+	if (buf == NULL) {
+		ret = -ENOMEM;
+		goto error;
+	}
 	if (pp->offset) {
 		ret = e_snprintf(offs, 32, "+%lu", pp->offset);
 		if (ret <= 0)
@@ -781,7 +795,8 @@
 error:
 	pr_debug("Failed to synthesize perf probe point: %s",
 		 strerror(-ret));
-	free(buf);
+	if (buf)
+		free(buf);
 	return NULL;
 }
 
@@ -890,7 +905,10 @@
 	char *buf;
 	int i, len, ret;
 
-	buf = xzalloc(MAX_CMDLEN);
+	buf = zalloc(MAX_CMDLEN);
+	if (buf == NULL)
+		return NULL;
+
 	len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s+%lu",
 			 tp->retprobe ? 'r' : 'p',
 			 tev->group, tev->event,
@@ -929,7 +947,9 @@
 
 	/* Convert trace_arg to probe_arg */
 	pev->nargs = tev->nargs;
-	pev->args = xzalloc(sizeof(struct perf_probe_arg) * pev->nargs);
+	pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
+	if (pev->args == NULL)
+		return -ENOMEM;
 	for (i = 0; i < tev->nargs && ret >= 0; i++)
 		if (tev->args[i].name)
 			pev->args[i].name = xstrdup(tev->args[i].name);
@@ -1326,25 +1346,31 @@
 					  struct kprobe_trace_event **tevs)
 {
 	struct symbol *sym;
-	int ntevs = 0, i;
+	int ret = 0, i;
 	struct kprobe_trace_event *tev;
 
 	/* Convert perf_probe_event with debuginfo */
-	ntevs = try_to_find_kprobe_trace_events(pev, tevs);
-	if (ntevs != 0)
-		return ntevs;
+	ret = try_to_find_kprobe_trace_events(pev, tevs);
+	if (ret != 0)
+		return ret;
 
 	/* Allocate trace event buffer */
-	ntevs = 1;
-	tev = *tevs = xzalloc(sizeof(struct kprobe_trace_event));
+	tev = *tevs = zalloc(sizeof(struct kprobe_trace_event));
+	if (tev == NULL)
+		return -ENOMEM;
 
 	/* Copy parameters */
 	tev->point.symbol = xstrdup(pev->point.function);
 	tev->point.offset = pev->point.offset;
 	tev->nargs = pev->nargs;
 	if (tev->nargs) {
-		tev->args = xzalloc(sizeof(struct kprobe_trace_arg)
-				    * tev->nargs);
+		tev->args = zalloc(sizeof(struct kprobe_trace_arg)
+				   * tev->nargs);
+		if (tev->args == NULL) {
+			free(tev);
+			*tevs = NULL;
+			return -ENOMEM;
+		}
 		for (i = 0; i < tev->nargs; i++) {
 			if (pev->args[i].name)
 				tev->args[i].name = xstrdup(pev->args[i].name);
@@ -1360,9 +1386,14 @@
 	if (!sym) {
 		pr_warning("Kernel symbol \'%s\' not found.\n",
 			   tev->point.symbol);
+		clear_kprobe_trace_event(tev);
+		free(tev);
+		*tevs = NULL;
 		return -ENOENT;
-	}
-	return ntevs;
+	} else
+		ret = 1;
+
+	return ret;
 }
 
 struct __event_package {
@@ -1377,7 +1408,9 @@
 	int i, j, ret;
 	struct __event_package *pkgs;
 
-	pkgs = xzalloc(sizeof(struct __event_package) * npevs);
+	pkgs = zalloc(sizeof(struct __event_package) * npevs);
+	if (pkgs == NULL)
+		return -ENOMEM;
 
 	/* Init vmlinux path */
 	ret = init_vmlinux();