file: stop printing packets if 0 columns are asked (found by clang).

This prevents a 0 bytes memory allocation (line 2383/4) and its subsequent
dereference (line 2399).

Change-Id: Ie88293699a55b9b48afe23d7371798e709bc1eaa
Reviewed-on: https://code.wireshark.org/review/25351
Petri-Dish: Dario Lombardo <lomato@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/file.c b/file.c
index 54172f6e89..79bfcde602 100644
--- a/file.c
+++ b/file.c
@@ -2372,6 +2372,10 @@ cf_print_packets(capture_file *cf, print_args_t *print_args,
         }
     }
 
+    /* if num_visible_col is 0, we are done */
+    if (num_visible_col == 0)
+      return CF_PRINT_OK;
+
     /* Find the widths for each of the columns - maximum of the
        width of the title and the width of the data - and construct
        a buffer with a line containing the column titles. */