From 2b523030cf8da39ac5f9c9bb189aac93f86dc3e8 Mon Sep 17 00:00:00 2001
From: Evgeny Khramtsov <ekhramtsov@process-one.net>
Date: Sun, 19 May 2019 11:22:41 +0300
Subject: [PATCH] Report better errors on SQL terms decode failure

---
 src/ejabberd_sql.erl | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/ejabberd_sql.erl b/src/ejabberd_sql.erl
index f807b0bca..3431e61b8 100644
--- a/src/ejabberd_sql.erl
+++ b/src/ejabberd_sql.erl
@@ -276,9 +276,23 @@ encode_term(Term) ->
 
 decode_term(Bin) ->
     Str = binary_to_list(<<Bin/binary, ".">>),
-    {ok, Tokens, _} = erl_scan:string(Str),
-    {ok, Term} = erl_parse:parse_term(Tokens),
-    Term.
+    try
+	{ok, Tokens, _} = erl_scan:string(Str),
+	{ok, Term} = erl_parse:parse_term(Tokens),
+	Term
+    catch _:{badmatch, {error, {Line, Mod, Reason}, _}} ->
+	    ?ERROR_MSG("Corrupted Erlang term in SQL database:~n"
+		       "** Scanner error: at line ~B: ~s~n"
+		       "** Term: ~s",
+		       [Line, Mod:format_error(Reason), Bin]),
+	    erlang:error(badarg);
+	  _:{badmatch, {error, {Line, Mod, Reason}}} ->
+	    ?ERROR_MSG("Corrupted Erlang term in SQL database:~n"
+		       "** Parser error: at line ~B: ~s~n"
+		       "** Term: ~s",
+		       [Line, Mod:format_error(Reason), Bin]),
+	    erlang:error(badarg)
+    end.
 
 -spec sqlite_db(binary()) -> atom().
 sqlite_db(Host) ->