Time parsing 32bit corner-case

[matteo-cristino]

Since time is an integer, it could take values from -2147483648 to 2147483647, but if I try to do

TIME.new(-2147483648)

the following error is returned

Could not read unix timestamp -2.147484e+09

While this error is not returned in the case I use

TIME.new("-2147483648")

This seems due to some conversion from number to string done internally in lua since, as stated in the documentation, both number and strings are seen as string from lua_isstring function (making also the lua_isnumber branching useless)

Zenroom/src/zen_time.c

Lines 74 to 121 in ca02f6c

	ztime_t* time_arg(lua_State *L, int n) {
	Z(L);
	ztime_t *result = (ztime_t*)malloc(sizeof(ztime_t));
	if(result == NULL) {
	return NULL;
	}
	void *ud = luaL_testudata(L, n, "zenroom.time");
	if(ud) {
	*result = *(ztime_t*)ud;
	goto end;
	}
	if(lua_isstring(L, 1)) {
	const char* arg = lua_tostring(L, 1);
	char *pEnd;
	long l_result = strtol(arg, &pEnd, 10);
	if(*pEnd) {
	free(result);
	lerror(L, "Could not read unix timestamp %s", arg);
	return NULL;
	} else if (l_result < INT_MIN || l_result > INT_MAX) {
	free(result);
	lerror(L, "Could not read unix timestamp %s out of range", arg);
	return NULL;
	}
	*result = (ztime_t)l_result;
	goto end;
	}
	// number argument, import
	if(lua_isnumber(L, 1)) {
	lua_Number number = lua_tonumber(L, 1);
	*result = (int)number;
	goto end;
	}
	octet *o = o_arg(L, n);
	if(o) {
	if(o->len != sizeof(ztime_t)) {
	free(result);
	zerror(L, "Wrong size timestamp %s", __func__);
	return NULL;
	}
	memcpy(result, o->val, sizeof(ztime_t));
	o_free(L, o);
	goto end;
	}
	end:
	if(result) Z->memcount_times++;
	return result;
	}

and thus they both pass thorugh the lua_tostring function. I tried also to move the branch with lua_isnumber before the lua_isstring one, but it seemed that after a certain number, lua was not able to read them correctly.

Thus at the moment, if we use numbers in input we are only loosing the time -2147483648 and using strings in input we should not lose anything. Anyway interesting to notice and maybe look further into it in case any other problems with numbers came up.

[jaromil]

Is this recently fenced off by fixing the js 32bit time conversion?

[jaromil]

Maybe related, found using ASAN

not ok 15 String dictionary with float and time
# (in test file /home/jrml/devel/zenroom/test/zencode/then.bats, line 265)
#   `cat <<EOF | zexe dictionary_string_float_time.zen dictionary_string_float_time.json' failed with status 134
# {
#     "dictionary": {
#         "str": "hello world!",
#         "num": 12345678910,
#         "time": 1702474699
#     }
# }
# Given I have the 'string dictionary' named 'dictionary'
# Then print all data
# Zenroom v4.46.1 - secure crypto language VM
# Zenroom is Copyright (C) 2017-2024 by the Dyne.org foundation
# reading DATA from file: /tmp/bats-run-MORy4w/file/0/dictionary_string_float_time.json
# EOF after 116 bytes
# loaded file (116 bytes)
# configuration: debug=1,rngseed=hex:00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
# reading Zencode from file: /tmp/bats-run-MORy4w/test/15/dictionary_string_float_time.zen
# EOF after 76 bytes
# loaded file (76 bytes)
# Direct Zencode execution
# [W]  Zencode is missing version check, please add: rule check version N.N.N
# src/zen_time.c:183:11: runtime error: 1.23457e+10 is outside the range of representable values of type 'int'
#     #0 0x562762adf2b7 in detect_time_value src/zen_time.c:183
#     #1 0x562762b23433 in precallC /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:529
#     #2 0x562762b246e4 in luaD_precall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:595
#     #3 0x562762bc3e88 in luaV_execute /home/jrml/devel/zenroom/lib/lua54/src/lvm.c:1682
#     #4 0x562762b25504 in ccall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:637
#     #5 0x562762b2565f in luaD_callnoyield /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:655
#     #6 0x562762b06db7 in f_call /home/jrml/devel/zenroom/lib/lua54/src/lapi.c:1038
#     #7 0x562762b1bfce in luaD_rawrunprotected /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:144
#     #8 0x562762b29068 in luaD_pcall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:957
#     #9 0x562762b07222 in lua_pcallk /home/jrml/devel/zenroom/lib/lua54/src/lapi.c:1064
#     #10 0x562762bd35d1 in luaB_pcall /home/jrml/devel/zenroom/lib/lua54/src/lbaselib.c:476
#     #11 0x562762b23433 in precallC /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:529
#     #12 0x562762b246e4 in luaD_precall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:595
#     #13 0x562762bc3e88 in luaV_execute /home/jrml/devel/zenroom/lib/lua54/src/lvm.c:1682
#     #14 0x562762b25504 in ccall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:637
#     #15 0x562762b2565f in luaD_callnoyield /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:655
#     #16 0x562762b06db7 in f_call /home/jrml/devel/zenroom/lib/lua54/src/lapi.c:1038
#     #17 0x562762b1bfce in luaD_rawrunprotected /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:144
#     #18 0x562762b29068 in luaD_pcall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:957
#     #19 0x562762b07222 in lua_pcallk /home/jrml/devel/zenroom/lib/lua54/src/lapi.c:1064
#     #20 0x562762bd35d1 in luaB_pcall /home/jrml/devel/zenroom/lib/lua54/src/lbaselib.c:476
#     #21 0x562762b23433 in precallC /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:529
#     #22 0x562762b246e4 in luaD_precall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:595
#     #23 0x562762bc3e88 in luaV_execute /home/jrml/devel/zenroom/lib/lua54/src/lvm.c:1682
#     #24 0x562762b25504 in ccall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:637
#     #25 0x562762b2565f in luaD_callnoyield /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:655
#     #26 0x562762b06db7 in f_call /home/jrml/devel/zenroom/lib/lua54/src/lapi.c:1038
#     #27 0x562762b1bfce in luaD_rawrunprotected /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:144
#     #28 0x562762b29068 in luaD_pcall /home/jrml/devel/zenroom/lib/lua54/src/ldo.c:957
#     #29 0x562762b07222 in lua_pcallk /home/jrml/devel/zenroom/lib/lua54/src/lapi.c:1064
#     #30 0x562762a55aa7 in zen_exec_zencode src/zenroom.c:380
#     #31 0x562762af3d44 in main src/cli-zenroom.c:427
#     #32 0x7f13847ec1c9 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
#     #33 0x7f13847ec28a in __libc_start_main_impl ../csu/libc-start.c:360
#     #34 0x562762a51384 in _start (/home/jrml/devel/zenroom/zenroom+0x3e1384) (BuildId: 5763bdd4c63058eaf41f4e887d10d941b1f19501)
#
# SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior src/zen_time.c:183:11 in