Sanatize result from bfd_find_nearest_line (BETTER_BACKTRACES)

bfd_find_nearest_line can possibly set file to null resulting in a crash when strrchr(file) runs

(closes issue ASTERISK-19815)
Reported by Mark Murawski
Tested by Mark Murawski

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@364635 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/logger.c b/main/logger.c
index d01e96ee8ddf4198b5267cce4c1dcef4fe3ecaa0..d895b7af49621b2a8ae62139b1a5a7f6dc4a75eb 100644 (file)
--- a/main/logger.c
+++ b/main/logger.c
@@ -1383,6 +1383,9 @@ char **ast_bt_get_symbols(void **addresses, size_t num_frames)
                                        continue;
                                }
 
+                                /* file can possibly be null even with a success result from bfd_find_nearest_line */
+                                file = file ? file : "";
+
                                /* Stack trace output */
                                found++;
                                if ((lastslash = strrchr(file, '/'))) {