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;
 
        /* 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 &&
                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. */
        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)
 error:
        pr_debug("Failed to synthesize perf probe point: %s",
                 strerror(-ret));
-       free(buf);
+       if (buf)
+               free(buf);
        return NULL;
 }
 
        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,
 
        /* 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);
                                          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);
        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 {
        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();
 
 /* 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;
                        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 */
 
        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;
                        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
 
        /* 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];
        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;