tools lib traceevent: Check return value of arg_to_str()

The arg_to_str() can fail so we should handle that case properly.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1335157118-14658-12-git-send-email-namhyung.kim@lge.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

diff --git a/tools/lib/traceevent/parse-filter.c b/tools/lib/traceevent/parse-filter.c
index d54c2b4dbd9f1d6a95b81e587b05ae96eae48f5b..f020ac61f9c11f8e5ad2327206fa9e82f9171f42 100644 (file)
--- a/tools/lib/traceevent/parse-filter.c
+++ b/tools/lib/traceevent/parse-filter.c
@@ -2026,11 +2026,13 @@ static char *exp_to_str(struct event_filter *filter, struct filter_arg *arg)
        char *lstr;
        char *rstr;
        char *op;
-       char *str;
+       char *str = NULL;
        int len;
 
        lstr = arg_to_str(filter, arg->exp.left);
        rstr = arg_to_str(filter, arg->exp.right);
+       if (!lstr || !rstr)
+               goto out;
 
        switch (arg->exp.type) {
        case FILTER_EXP_ADD:
@@ -2070,6 +2072,7 @@ static char *exp_to_str(struct event_filter *filter, struct filter_arg *arg)
        len = strlen(op) + strlen(lstr) + strlen(rstr) + 4;
        str = malloc_or_die(len);
        snprintf(str, len, "%s %s %s", lstr, op, rstr);
+out:
        free(lstr);
        free(rstr);
 
@@ -2086,6 +2089,8 @@ static char *num_to_str(struct event_filter *filter, struct filter_arg *arg)
 
        lstr = arg_to_str(filter, arg->num.left);
        rstr = arg_to_str(filter, arg->num.right);
+       if (!lstr || !rstr)
+               goto out;
 
        switch (arg->num.type) {
        case FILTER_CMP_EQ:
@@ -2122,6 +2127,7 @@ static char *num_to_str(struct event_filter *filter, struct filter_arg *arg)
                break;
        }
 
+out:
        free(lstr);
        free(rstr);
        return str;
@@ -2272,7 +2278,12 @@ int pevent_filter_compare(struct event_filter *filter1, struct event_filter *fil
                /* The best way to compare complex filters is with strings */
                str1 = arg_to_str(filter1, filter_type1->filter);
                str2 = arg_to_str(filter2, filter_type2->filter);
-               result = strcmp(str1, str2) != 0;
+               if (str1 && str2)
+                       result = strcmp(str1, str2) != 0;
+               else
+                       /* bail out if allocation fails */
+                       result = 1;
+
                free(str1);
                free(str2);
                if (result)