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>

2 files changed, 69 insertions, 25 deletions

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index bd68f7b33b21..aacbf730b475 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -556,7 +556,9 @@ static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
         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 @@ int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
 
         /* 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 @@ int parse_kprobe_trace_command(const char *cmd, struct kprobe_trace_event *tev)
                 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 @@ static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
         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 @@ static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
 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 *synthesize_kprobe_trace_command(struct kprobe_trace_event *tev)
         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 @@ int convert_to_perf_probe_event(struct kprobe_trace_event *tev,
 
         /* 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 @@ static int convert_to_kprobe_trace_events(struct perf_probe_event *pev,
                                           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 @@ static int convert_to_kprobe_trace_events(struct perf_probe_event *pev,
         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 add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
         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();
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 54daa91e901d..ce1ac827f3d2 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -111,7 +111,7 @@ static int strtailcmp(const char *s1, const char *s2)
 /* Line number list operations */
 
 /* Add a line to line number list */
-static void line_list__add_line(struct list_head *head, unsigned int line)
+static int line_list__add_line(struct list_head *head, unsigned int line)
 {
         struct line_node *ln;
         struct list_head *p;
@@ -122,16 +122,19 @@ static void line_list__add_line(struct list_head *head, unsigned int line)
                         p = &ln->list;
                         goto found;
                 } else if (ln->line == line)    /* Already exist */
-                        return ;
+                        return 1;
         }
         /* List is empty, or the smallest entry */
         p = head;
 found:
         pr_debug("line list: add a line %u\n", line);
-        ln = xzalloc(sizeof(struct line_node));
+        ln = zalloc(sizeof(struct line_node));
+        if (ln == NULL)
+                return -ENOMEM;
         ln->line = line;
         INIT_LIST_HEAD(&ln->list);
         list_add(&ln->list, p);
+        return 0;
 }
 
 /* Check if the line in line number list */
@@ -423,7 +426,9 @@ static int convert_location(Dwarf_Op *op, struct probe_finder *pf)
 
         tvar->value = xstrdup(regs);
         if (ref) {
-                tvar->ref = xzalloc(sizeof(struct kprobe_trace_arg_ref));
+                tvar->ref = zalloc(sizeof(struct kprobe_trace_arg_ref));
+                if (tvar->ref == NULL)
+                        return -ENOMEM;
                 tvar->ref->offset = (long)offs;
         }
         return 0;
@@ -500,7 +505,9 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
                         return -EINVAL;
                 }
 
-                ref = xzalloc(sizeof(struct kprobe_trace_arg_ref));
+                ref = zalloc(sizeof(struct kprobe_trace_arg_ref));
+                if (ref == NULL)
+                        return -ENOMEM;
                 if (*ref_ptr)
                         (*ref_ptr)->next = ref;
                 else
@@ -680,7 +687,9 @@ static int convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
 
         /* Find each argument */
         tev->nargs = pf->pev->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)
+                return -ENOMEM;
         for (i = 0; i < pf->pev->nargs; i++) {
                 pf->pvar = &pf->pev->args[i];
                 pf->tvar = &tev->args[i];
@@ -938,7 +947,9 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
         Dwarf *dbg;
         int ret = 0;
 
-        pf.tevs = xzalloc(sizeof(struct kprobe_trace_event) * MAX_PROBES);
+        pf.tevs = zalloc(sizeof(struct kprobe_trace_event) * MAX_PROBES);
+        if (pf.tevs == NULL)
+                return -ENOMEM;
         *tevs = pf.tevs;
         pf.ntevs = 0;