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Istvan Miklos
committed
Add RegExp recursion depth limit
The regexp engine does not have any recursion depth check, thus it can cause problems with various regexps. Added a new build option `--regexp-recursion-limit N` whose default value is 1000. For unlimited recursion depth use 0. Also added a build-option-test for the unlimited recursion depth. Fixes #2448 JerryScript-DCO-1.0-Signed-off-by: Istvan Miklos imiklos2@inf.u-szeged.hu
1 parent 9ab33e8 commit 4b1a08c

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8 files changed

+79
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‎jerry-core/CMakeLists.txt‎

Lines changed: 7 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -39,6 +39,7 @@ set(FEATURE_SYSTEM_ALLOCATOR OFF CACHE BOOL "Enable system allocator?")
3939
set(FEATURE_VALGRIND OFF CACHE BOOL "Enable Valgrind support?")
4040
set(FEATURE_VM_EXEC_STOP OFF CACHE BOOL "Enable VM execution stopping?")
4141
set(MEM_HEAP_SIZE_KB "512" CACHE STRING "Size of memory heap, in kilobytes")
42+
set(REGEXP_RECURSION_LIMIT "0" CACHE STRING "Limit of regexp recurion depth")
4243

4344
# Option overrides
4445
if(USING_MSVC)
@@ -94,6 +95,7 @@ message(STATUS "FEATURE_SYSTEM_ALLOCATOR " ${FEATURE_SYSTEM_ALLOCATOR})
9495
message(STATUS "FEATURE_VALGRIND " ${FEATURE_VALGRIND})
9596
message(STATUS "FEATURE_VM_EXEC_STOP " ${FEATURE_VM_EXEC_STOP})
9697
message(STATUS "MEM_HEAP_SIZE_KB " ${MEM_HEAP_SIZE_KB})
98+
message(STATUS "REGEXP_RECURSION_LIMIT " ${REGEXP_RECURSION_LIMIT})
9799

98100
# Include directories
99101
set(INCLUDE_CORE_PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include")
@@ -242,6 +244,11 @@ if(FEATURE_REGEXP_STRICT_MODE)
242244
set(DEFINES_JERRY ${DEFINES_JERRY} ENABLE_REGEXP_STRICT_MODE)
243245
endif()
244246

247+
# RegExp recursion depth limit
248+
if(REGEXP_RECURSION_LIMIT)
249+
set(DEFINES_JERRY ${DEFINES_JERRY} REGEXP_RECURSION_LIMIT=${REGEXP_RECURSION_LIMIT})
250+
endif()
251+
245252
# RegExp byte-code dumps
246253
if(FEATURE_REGEXP_DUMP)
247254
set(DEFINES_JERRY ${DEFINES_JERRY} REGEXP_DUMP_BYTE_CODE)

‎jerry-core/ecma/operations/ecma-regexp-object.c‎

Lines changed: 43 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -63,6 +63,13 @@
6363
*/
6464
#define RE_IS_CAPTURE_GROUP(x) (((x) < RE_OP_NON_CAPTURE_GROUP_START) ? 1 : 0)
6565

66+
/**
67+
* Check RegExp recursion depth limit
68+
*/
69+
#ifdef REGEXP_RECURSION_LIMIT
70+
JERRY_STATIC_ASSERT (REGEXP_RECURSION_LIMIT > 0, regexp_recursion_limit_must_be_greater_than_zero);
71+
#endif /* REGEXP_RECURSION_LIMIT */
72+
6673
/**
6774
* Parse RegExp flags (global, ignoreCase, multiline)
6875
*
@@ -364,6 +371,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
364371
const lit_utf8_byte_t *str_p, /**< input string pointer */
365372
const lit_utf8_byte_t **out_str_p) /**< [out] matching substring iterator */
366373
{
374+
REGEXP_RECURSION_COUNTER_DECREASE_AND_TEST ();
367375
const lit_utf8_byte_t *str_curr_p = str_p;
368376

369377
while (true)
@@ -376,12 +384,14 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
376384
{
377385
JERRY_TRACE_MSG ("Execute RE_OP_MATCH: match\n");
378386
*out_str_p = str_curr_p;
387+
REGEXP_RECURSION_COUNTER_INCREASE ();
379388
return ECMA_VALUE_TRUE; /* match */
380389
}
381390
case RE_OP_CHAR:
382391
{
383392
if (str_curr_p >= re_ctx_p->input_end_p)
384393
{
394+
REGEXP_RECURSION_COUNTER_INCREASE ();
385395
return ECMA_VALUE_FALSE; /* fail */
386396
}
387397

@@ -393,6 +403,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
393403
if (ch1 != ch2)
394404
{
395405
JERRY_TRACE_MSG ("fail\n");
406+
REGEXP_RECURSION_COUNTER_INCREASE ();
396407
return ECMA_VALUE_FALSE; /* fail */
397408
}
398409

@@ -404,6 +415,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
404415
{
405416
if (str_curr_p >= re_ctx_p->input_end_p)
406417
{
418+
REGEXP_RECURSION_COUNTER_INCREASE ();
407419
return ECMA_VALUE_FALSE; /* fail */
408420
}
409421

@@ -413,6 +425,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
413425
if (lit_char_is_line_terminator (ch))
414426
{
415427
JERRY_TRACE_MSG ("fail\n");
428+
REGEXP_RECURSION_COUNTER_INCREASE ();
416429
return ECMA_VALUE_FALSE; /* fail */
417430
}
418431

@@ -432,6 +445,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
432445
if (!(re_ctx_p->flags & RE_FLAG_MULTILINE))
433446
{
434447
JERRY_TRACE_MSG ("fail\n");
448+
REGEXP_RECURSION_COUNTER_INCREASE ();
435449
return ECMA_VALUE_FALSE; /* fail */
436450
}
437451

@@ -442,6 +456,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
442456
}
443457

444458
JERRY_TRACE_MSG ("fail\n");
459+
REGEXP_RECURSION_COUNTER_INCREASE ();
445460
return ECMA_VALUE_FALSE; /* fail */
446461
}
447462
case RE_OP_ASSERT_END:
@@ -457,6 +472,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
457472
if (!(re_ctx_p->flags & RE_FLAG_MULTILINE))
458473
{
459474
JERRY_TRACE_MSG ("fail\n");
475+
REGEXP_RECURSION_COUNTER_INCREASE ();
460476
return ECMA_VALUE_FALSE; /* fail */
461477
}
462478

@@ -467,6 +483,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
467483
}
468484

469485
JERRY_TRACE_MSG ("fail\n");
486+
REGEXP_RECURSION_COUNTER_INCREASE ();
470487
return ECMA_VALUE_FALSE; /* fail */
471488
}
472489
case RE_OP_ASSERT_WORD_BOUNDARY:
@@ -498,6 +515,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
498515
if (is_wordchar_left == is_wordchar_right)
499516
{
500517
JERRY_TRACE_MSG ("fail\n");
518+
REGEXP_RECURSION_COUNTER_INCREASE ();
501519
return ECMA_VALUE_FALSE; /* fail */
502520
}
503521
}
@@ -509,6 +527,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
509527
if (is_wordchar_left != is_wordchar_right)
510528
{
511529
JERRY_TRACE_MSG ("fail\n");
530+
REGEXP_RECURSION_COUNTER_INCREASE ();
512531
return ECMA_VALUE_FALSE; /* fail */
513532
}
514533
}
@@ -563,6 +582,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
563582

564583
if (!ECMA_IS_VALUE_ERROR (match_value))
565584
{
585+
REGEXP_RECURSION_COUNTER_INCREASE ();
566586
if (ecma_is_value_true (match_value))
567587
{
568588
*out_str_p = sub_str_p;
@@ -588,6 +608,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
588608
if (str_curr_p >= re_ctx_p->input_end_p)
589609
{
590610
JERRY_TRACE_MSG ("fail\n");
611+
REGEXP_RECURSION_COUNTER_INCREASE ();
591612
return ECMA_VALUE_FALSE; /* fail */
592613
}
593614

@@ -618,6 +639,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
618639
if (!is_match)
619640
{
620641
JERRY_TRACE_MSG ("fail\n");
642+
REGEXP_RECURSION_COUNTER_INCREASE ();
621643
return ECMA_VALUE_FALSE; /* fail */
622644
}
623645
}
@@ -627,6 +649,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
627649
if (is_match)
628650
{
629651
JERRY_TRACE_MSG ("fail\n");
652+
REGEXP_RECURSION_COUNTER_INCREASE ();
630653
return ECMA_VALUE_FALSE; /* fail */
631654
}
632655
}
@@ -657,6 +680,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
657680
if (str_curr_p >= re_ctx_p->input_end_p)
658681
{
659682
JERRY_TRACE_MSG ("fail\n");
683+
REGEXP_RECURSION_COUNTER_INCREASE ();
660684
return ECMA_VALUE_FALSE; /* fail */
661685
}
662686

@@ -666,6 +690,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
666690
if (ch1 != ch2)
667691
{
668692
JERRY_TRACE_MSG ("fail\n");
693+
REGEXP_RECURSION_COUNTER_INCREASE ();
669694
return ECMA_VALUE_FALSE; /* fail */
670695
}
671696
}
@@ -689,6 +714,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
689714
if (ecma_is_value_true (match_value))
690715
{
691716
*out_str_p = sub_str_p;
717+
REGEXP_RECURSION_COUNTER_INCREASE ();
692718
return match_value; /* match */
693719
}
694720
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -703,13 +729,15 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
703729
bc_p = old_bc_p;
704730

705731
re_ctx_p->saved_p[RE_GLOBAL_START_IDX] = old_start_p;
732+
REGEXP_RECURSION_COUNTER_INCREASE ();
706733
return ECMA_VALUE_FALSE; /* fail */
707734
}
708735
case RE_OP_SAVE_AND_MATCH:
709736
{
710737
JERRY_TRACE_MSG ("End of pattern is reached: match\n");
711738
re_ctx_p->saved_p[RE_GLOBAL_END_IDX] = str_curr_p;
712739
*out_str_p = str_curr_p;
740+
REGEXP_RECURSION_COUNTER_INCREASE ();
713741
return ECMA_VALUE_TRUE; /* match */
714742
}
715743
case RE_OP_ALTERNATIVE:
@@ -774,6 +802,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
774802
if (ecma_is_value_true (match_value))
775803
{
776804
*out_str_p = sub_str_p;
805+
REGEXP_RECURSION_COUNTER_INCREASE ();
777806
return match_value; /* match */
778807
}
779808
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -832,6 +861,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
832861
if (ecma_is_value_true (match_value))
833862
{
834863
*out_str_p = sub_str_p;
864+
REGEXP_RECURSION_COUNTER_INCREASE ();
835865
return match_value; /* match */
836866
}
837867
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -856,6 +886,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
856886
if (ecma_is_value_true (match_value))
857887
{
858888
*out_str_p = sub_str_p;
889+
REGEXP_RECURSION_COUNTER_INCREASE ();
859890
return match_value; /* match */
860891
}
861892
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -865,6 +896,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
865896
}
866897

867898
re_ctx_p->saved_p[start_idx] = old_start_p;
899+
REGEXP_RECURSION_COUNTER_INCREASE ();
868900
return ECMA_VALUE_FALSE; /* fail */
869901
}
870902
case RE_OP_CAPTURE_NON_GREEDY_GROUP_END:
@@ -910,6 +942,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
910942
if (ecma_is_value_true (match_value))
911943
{
912944
*out_str_p = sub_str_p;
945+
REGEXP_RECURSION_COUNTER_INCREASE ();
913946
return match_value; /* match */
914947
}
915948
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -958,6 +991,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
958991
if (re_ctx_p->num_of_iterations_p[iter_idx] >= min
959992
&& str_curr_p== re_ctx_p->saved_p[start_idx])
960993
{
994+
REGEXP_RECURSION_COUNTER_INCREASE ();
961995
return ECMA_VALUE_FALSE; /* fail */
962996
}
963997

@@ -979,6 +1013,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
9791013
if (ecma_is_value_true (match_value))
9801014
{
9811015
*out_str_p = sub_str_p;
1016+
REGEXP_RECURSION_COUNTER_INCREASE ();
9821017
return match_value; /* match */
9831018
}
9841019
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -1003,6 +1038,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
10031038
if (ecma_is_value_true (match_value))
10041039
{
10051040
*out_str_p = sub_str_p;
1041+
REGEXP_RECURSION_COUNTER_INCREASE ();
10061042
return match_value; /* match */
10071043
}
10081044
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -1024,6 +1060,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
10241060
if (ecma_is_value_true (match_value))
10251061
{
10261062
*out_str_p = sub_str_p;
1063+
REGEXP_RECURSION_COUNTER_INCREASE ();
10271064
return match_value; /* match */
10281065
}
10291066
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -1035,6 +1072,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
10351072
/* restore if fails */
10361073
re_ctx_p->saved_p[end_idx] = old_end_p;
10371074
re_ctx_p->num_of_iterations_p[iter_idx]--;
1075+
REGEXP_RECURSION_COUNTER_INCREASE ();
10381076
return ECMA_VALUE_FALSE; /* fail */
10391077
}
10401078
case RE_OP_NON_GREEDY_ITERATOR:
@@ -1059,6 +1097,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
10591097
if (ecma_is_value_true (match_value))
10601098
{
10611099
*out_str_p = sub_str_p;
1100+
REGEXP_RECURSION_COUNTER_INCREASE ();
10621101
return match_value; /* match */
10631102
}
10641103
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -1082,6 +1121,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
10821121
str_curr_p = sub_str_p;
10831122
num_of_iter++;
10841123
}
1124+
REGEXP_RECURSION_COUNTER_INCREASE ();
10851125
return ECMA_VALUE_FALSE; /* fail */
10861126
}
10871127
default:
@@ -1125,6 +1165,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
11251165
if (ecma_is_value_true (match_value))
11261166
{
11271167
*out_str_p = sub_str_p;
1168+
REGEXP_RECURSION_COUNTER_INCREASE ();
11281169
return match_value; /* match */
11291170
}
11301171
else if (ECMA_IS_VALUE_ERROR (match_value))
@@ -1140,6 +1181,7 @@ re_match_regexp (re_matcher_ctx_t *re_ctx_p, /**< RegExp matcher context */
11401181
lit_utf8_read_prev (&str_curr_p);
11411182
num_of_iter--;
11421183
}
1184+
REGEXP_RECURSION_COUNTER_INCREASE ();
11431185
return ECMA_VALUE_FALSE; /* fail */
11441186
}
11451187
}
@@ -1232,6 +1274,7 @@ ecma_regexp_exec_helper (ecma_value_t regexp_value, /**< RegExp object */
12321274
re_ctx.input_start_p = input_curr_p;
12331275
const lit_utf8_byte_t *input_end_p = re_ctx.input_start_p + input_buffer_size;
12341276
re_ctx.input_end_p = input_end_p;
1277+
REGEXP_RECURSION_COUNTER_INIT ();
12351278

12361279
/* 1. Read bytecode header and init regexp matcher context. */
12371280
re_ctx.flags = bc_p->header.status_flags;

‎jerry-core/ecma/operations/ecma-regexp-object.h‎

Lines changed: 16 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -18,6 +18,19 @@
1818

1919
#ifndef CONFIG_DISABLE_REGEXP_BUILTIN
2020

21+
#ifdef REGEXP_RECURSION_LIMIT
22+
#define REGEXP_RECURSION_COUNTER_DECREASE_AND_TEST() if (--re_ctx_p->recursion_counter == 0) \
23+
{ \
24+
return ecma_raise_range_error (ECMA_ERR_MSG ("RegExp executor recursion limit is exceeded.")); \
25+
}
26+
#define REGEXP_RECURSION_COUNTER_INCREASE() (++re_ctx_p->recursion_counter)
27+
#define REGEXP_RECURSION_COUNTER_INIT() (re_ctx.recursion_counter = REGEXP_RECURSION_LIMIT)
28+
#else
29+
#define REGEXP_RECURSION_COUNTER_DECREASE_AND_TEST()
30+
#define REGEXP_RECURSION_COUNTER_INCREASE()
31+
#define REGEXP_RECURSION_COUNTER_INIT()
32+
#endif /* REGEXP_RECURSION_LIMIT */
33+
2134
#include "ecma-globals.h"
2235
#include "re-compiler.h"
2336

@@ -46,6 +59,9 @@ typedef struct
4659
const lit_utf8_byte_t **saved_p; /**< saved result string pointers, ECMA 262 v5, 15.10.2.1, State */
4760
const lit_utf8_byte_t *input_start_p; /**< start of input pattern string */
4861
const lit_utf8_byte_t *input_end_p; /**< end of input pattern string */
62+
#ifdef REGEXP_RECURSION_LIMIT
63+
uint32_t recursion_counter; /**< RegExp recursion counter */
64+
#endif /* REGEXP_RECURSION_LIMIT */
4965
uint32_t num_of_captures; /**< number of capture groups */
5066
uint32_t num_of_non_captures; /**< number of non-capture groups */
5167
uint32_t *num_of_iterations_p; /**< number of iterations */

‎jerry-core/parser/regexp/re-compiler.c‎

Lines changed: 4 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -246,6 +246,7 @@ static ecma_value_t
246246
re_parse_alternative (re_compiler_ctx_t *re_ctx_p, /**< RegExp compiler context */
247247
bool expect_eof) /**< expect end of file */
248248
{
249+
REGEXP_RECURSION_COUNTER_DECREASE_AND_TEST ();
249250
uint32_t idx;
250251
re_bytecode_ctx_t *bc_ctx_p = re_ctx_p->bytecode_ctx_p;
251252
ecma_value_t ret_value = ECMA_VALUE_EMPTY;
@@ -440,6 +441,7 @@ re_parse_alternative (re_compiler_ctx_t *re_ctx_p, /**< RegExp compiler context
440441
else
441442
{
442443
re_insert_u32 (bc_ctx_p, alterantive_offset, re_get_bytecode_length (bc_ctx_p) - alterantive_offset);
444+
REGEXP_RECURSION_COUNTER_INCREASE ();
443445
should_loop = false;
444446
}
445447
break;
@@ -453,6 +455,7 @@ re_parse_alternative (re_compiler_ctx_t *re_ctx_p, /**< RegExp compiler context
453455
else
454456
{
455457
re_insert_u32 (bc_ctx_p, alterantive_offset, re_get_bytecode_length (bc_ctx_p) - alterantive_offset);
458+
REGEXP_RECURSION_COUNTER_INCREASE ();
456459
should_loop = false;
457460
}
458461

@@ -559,7 +562,7 @@ re_compile_bytecode (const re_compiled_code_t **out_bytecode_p, /**< [out] point
559562
re_ctx.flags = flags;
560563
re_ctx.highest_backref = 0;
561564
re_ctx.num_of_non_captures = 0;
562-
565+
REGEXP_RECURSION_COUNTER_INIT ();
563566
re_bytecode_ctx_t bc_ctx;
564567
bc_ctx.block_start_p = NULL;
565568
bc_ctx.block_end_p = NULL;

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