Always memset the packet-header struct in Lua to avoid

crashes from garbage data.

Also, give Lua a copy of the packet comment if there is one.

Fixes: https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=7538

svn path=/trunk/; revision=44093

1 files changed, 17 insertions, 7 deletions

diff --git a/epan/wslua/wslua_dumper.c b/epan/wslua/wslua_dumper.c
index f2b3077513..786d247226 100644
--- a/epan/wslua/wslua_dumper.c
+++ b/epan/wslua/wslua_dumper.c
@@ -291,13 +291,18 @@ WSLUA_METHOD Dumper_dump(lua_State* L) {
 
     if (! ba) WSLUA_ARG_ERROR(Dumper_dump,BYTEARRAY,"must be a ByteArray");
 
-    pkthdr.ts.secs = (unsigned)floor(ts);
+    memset(&pkthdr, 0, sizeof(pkthdr));
+
+    pkthdr.ts.secs  = (unsigned)floor(ts);
     pkthdr.ts.nsecs = (unsigned)floor((ts - (double)pkthdr.ts.secs) * 1000000000);
 
-    pkthdr.len  = ba->len;
-    pkthdr.caplen  = ba->len;
+    pkthdr.len       = ba->len;
+    pkthdr.caplen    = ba->len;
     pkthdr.pkt_encap = DUMPER_ENCAP(d);
 
+    /* TODO: Can we get access to pinfo->fd->opt_comment here somehow? We
+     * should be copying it to pkthdr.opt_comment if we can. */
+
     if (! wtap_dump(d, &pkthdr, ph->wph, ba->data, &err)) {
         luaL_error(L,"error while dumping: %s",
                    wtap_strerror(err));
@@ -370,12 +375,17 @@ WSLUA_METHOD Dumper_dump_current(lua_State* L) {
 
     tvb = data_src->tvb;
 
-    pkthdr.ts.secs = lua_pinfo->fd->abs_ts.secs;
-    pkthdr.ts.nsecs = lua_pinfo->fd->abs_ts.nsecs;
-    pkthdr.len  = tvb_reported_length(tvb);
-    pkthdr.caplen  = tvb_length(tvb);
+    memset(&pkthdr, 0, sizeof(pkthdr));
+
+    pkthdr.ts.secs   = lua_pinfo->fd->abs_ts.secs;
+    pkthdr.ts.nsecs  = lua_pinfo->fd->abs_ts.nsecs;
+    pkthdr.len       = tvb_reported_length(tvb);
+    pkthdr.caplen    = tvb_length(tvb);
     pkthdr.pkt_encap = lua_pinfo->fd->lnk_t;
 
+    if (lua_pinfo->fd->opt_comment)
+        pkthdr.opt_comment = ep_strdup(lua_pinfo->fd->opt_comment);
+
     data = ep_tvb_memdup(tvb,0,pkthdr.caplen);
 
     if (! wtap_dump(d, &pkthdr, lua_pinfo->pseudo_header, data, &err)) {