Multiple memory leaks with 6.1.1 (and 5.9.6)

[bdb]

Onig has several leaks when an invalid pattern is passed and the parser returns an error.

Here are 3 patterns we use in our tests:

"[ab+"
"[ab]+"
"(\d:"

Each one causes a different parse error, respectively:

-103
-104
-117

And each one results in leaks as reported by GCC 5.4 and ASAN/LSAN (on Ubuntu 16.04 with all patches applied).

Here are 2 examples. I traced the first example by breaking on the only instance of ONIGERR_PREMATURE_END_OF_CHAR_CLASS in regparse.c and stepping out from there.

The root problem seems to be in parse_exp() where some return paths cause the 'qn' node to leak. I do not know the exact paths as I was stepping out from the error point.

In the 1st case below, the allocation of 'qn' occurs in the 'repeat' goto on line 5165 (frame 3). Then in the TK_CC_OPEN case handler in parse_exp() when parse_char_class() fails, parse_exp() immediately returns at that point leaking a live 'qn' allocation.

These leaks should be fixed as they could cause issues with a long running app that allows users to enter random patterns of their own (through UI or through a config file).

For our tests too, these leaks cause test harness failures with ASAN leaks active, so we have to disable ASAN leaks for our test harness.

`Direct leak of 56 byte(s) in 1 object(s) allocated from:
#0 0x7ffff6f02602 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x98602)
#1 0x85c6ab in node_new /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:1072
#2 0x85cbb5 in node_new_quantifier /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:1252
#3 0x865c73 in parse_exp /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5165
#4 0x865eb6 in parse_branch /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5222
#5 0x866048 in parse_subexp /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5259
#6 0x866204 in parse_regexp /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5304
#7 0x866324 in onig_parse_make_tree /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5335
#8 0x870d60 in onig_compile /home/src/core/modules/regex/vendor/onig/onig/src/regcomp.c:5279
#9 0x871448 in onig_new /home/src/core/modules/regex/vendor/onig/onig/src/regcomp.c:5518
...

Direct leak of 56 byte(s) in 1 object(s) allocated from:
#0 0x7ffff6f02602 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x98602)
#1 0x85c6ab in node_new /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:1072
#2 0x85cc67 in node_new_enclose /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:1278
#3 0x85cd05 in node_new_enclose_memory /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:1301
#4 0x86491a in parse_enclose /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:4639
#5 0x8651ca in parse_exp /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:4899
#6 0x865eb6 in parse_branch /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5222
#7 0x866048 in parse_subexp /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5259
#8 0x866204 in parse_regexp /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5304
#9 0x866324 in onig_parse_make_tree /home/src/core/modules/regex/vendor/onig/onig/src/regparse.c:5335
#10 0x870d60 in onig_compile /home/src/core/modules/regex/vendor/onig/onig/src/regcomp.c:5279
#11 0x871448 in onig_new /home/src/core/modules/regex/vendor/onig/onig/src/regcomp.c:5518
...`

[kkos]

I think these problems has been fixed in develop branch by #26, #27 and #29.