perf probe: Check for dup and fdopen failures

dup and fdopen can potentially fail, so add some extra
error handling checks rather than assuming they always work.

Signed-off-by: Colin King <colin.king@canonical.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1471038296-12956-1-git-send-email-colin.king@canonical.com
[ Free resources when those functions (now being verified) fail ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 9aed9c3..a8e7623 100644 (file)
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -133,7 +133,7 @@ int probe_file__open_both(int *kfd, int *ufd, int flag)
 /* Get raw string list of current kprobe_events  or uprobe_events */
 struct strlist *probe_file__get_rawlist(int fd)
 {
-       int ret, idx;
+       int ret, idx, fddup;
        FILE *fp;
        char buf[MAX_CMDLEN];
        char *p;
@@ -144,7 +144,14 @@ struct strlist *probe_file__get_rawlist(int fd)
 
        sl = strlist__new(NULL, NULL);
 
-       fp = fdopen(dup(fd), "r");
+       fddup = dup(fd);
+       if (fddup < 0)
+               goto out_free_sl;
+
+       fp = fdopen(fddup, "r");
+       if (!fp)
+               goto out_close_fddup;
+
        while (!feof(fp)) {
                p = fgets(buf, MAX_CMDLEN, fp);
                if (!p)
@@ -163,6 +170,12 @@ struct strlist *probe_file__get_rawlist(int fd)
        fclose(fp);
 
        return sl;
+
+out_close_fddup:
+       close(fddup);
+out_free_sl:
+       strlist__delete(sl);
+       return NULL;
 }
 
 static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
@@ -447,10 +460,13 @@ static int probe_cache__load(struct probe_cache *pcache)
 {
        struct probe_cache_entry *entry = NULL;
        char buf[MAX_CMDLEN], *p;
-       int ret = 0;
+       int ret = 0, fddup;
        FILE *fp;
 
-       fp = fdopen(dup(pcache->fd), "r");
+       fddup = dup(pcache->fd);
+       if (fddup < 0)
+               return -errno;
+       fp = fdopen(fddup, "r");
        if (!fp)
                return -EINVAL;