From: Vincent JARDIN <vincent.jardin@6wind.com>
Date: Mon, 9 Oct 2017 10:42:11 +0000 (+0200)
Subject: lib: fix NULL->field_len access
X-Git-Tag: frr-4.0-dev~230^2~1
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=43b798b7dd149782d9dbad58c1a849d6d528b1d2;p=matthieu%2Ffrr.git

lib: fix NULL->field_len access

Currenlty, this function is used only by:
  - unit test of csv.c (see its main() section)
  - ptm_lib.c

In case of ptm, it is safe to return NULL because:
  csv_encode_record() -> return NULL
     _ptm_lib_encode_header() -> return NULL
        the only consumer of the return value is: ptm_lib_init_msg()
        that checks the NULL return.

Warning:
  Access to field 'field_len' results in a dereference of a null
  pointer (loaded from variable 'fld')

Signed-off-by: Vincent Jardin <vincent.jardin@6wind.com>
---

diff --git a/lib/csv.c b/lib/csv.c
index 0ad5c74be3..45582e3092 100644
--- a/lib/csv.c
+++ b/lib/csv.c
@@ -284,6 +284,8 @@ csv_record_t *csv_encode_record(csv_t *csv, csv_record_t *rec, int count, ...)
 
 	va_start(list, count);
 	str = csv_field_iter(rec, &fld);
+	if (!fld)
+		return NULL;
 	for (tempc = 0; tempc < count; tempc++) {
 		col = va_arg(list, char *);
 		for (i = 0; i < fld->field_len; i++) {