Platform: Code4rena
Start Date: 20/09/2022
Pot Size: $30,000 USDC
Total HM: 12
Participants: 198
Period: 3 days
Judge: 0xean
Total Solo HM: 2
Id: 164
League: ETH
Rank: 80/198
Findings: 3
Award: $28.69
🌟 Selected for report: 0
🚀 Solo Findings: 0
🌟 Selected for report: Czar102
Also found by: 0xDecorativePineapple, 0xNazgul, 0xSky, 0xbepresent, 0xmatt, Atarpara, Bahurum, DimitarDimitrov, Franfran, GimelSec, JGcarv, JLevick, Junnon, OptimismSec, Rolezn, Ruhum, Soosh, Tomo, Trust, __141345__, adriro, ajtra, bin2chen, cRat1st0s, cccz, cryptonue, d3e4, innertia, jag, joestakey, neumo, obront, pashov, pauliax, pcarranzav, peanuts, rajatbeladiya, rbserver, reassor, seyni, wagmi, zzykxx, zzzitron
0.7375 USDC - $0.74
In VariableSupplyERC20Token.sol maxSupply_
is used to set a limit to the amount mintable, and a value of 0 is used to represent an infinite limit. 0 is indeed a nonsensical value for this variable, and as such would be suitable to represent infinity, but mintableSupply
takes its value from maxSupply_
, and here we have a clash as a mintableSupply
of 0 simply means that nothing more should be minted.
Suppose a VariableSupplyERC20Token was created with a positive maxSupply_
, which means that the supply should be limited. If mint
is called with an amount
equal to mintableSupply
, then mintableSupply
will be set to 0 at line 43. Now, mint
will behave as if the supply is unlimited (contrary to our expectations and with unlimited possiblity of inflation).
Code inspection
Use another representation for infinite supply, for example type(uint256).max
.
#0 - 0xean
2022-09-24T00:16:41Z
dupe of #3
🌟 Selected for report: AkshaySrivastav
Also found by: 0v3rf10w, 0x040, 0x1f8b, 0x4non, 0x5rings, 0x85102, 0xA5DF, 0xDecorativePineapple, 0xNazgul, 0xSky, 0xSmartContract, 0xbepresent, 0xf15ers, 0xmatt, 2997ms, Aeros, Aymen0909, B2, Bahurum, Bnke0x0, CertoraInc, Chom, ChristianKuri, CodingNameKiki, Deivitto, Diana, Diraco, Dravee, ElKu, Funen, IllIllI, JC, JLevick, JohnSmith, JohnnyTime, KIntern_NA, Lambda, Margaret, MasterCookie, OptimismSec, RaymondFam, Respx, ReyAdmirado, RockingMiles, Rohan16, Rolezn, Ruhum, RustyRabbit, Sm4rty, SooYa, StevenL, TomJ, Tomo, V_B, Waze, Yiko, __141345__, a12jmx, ajtra, ak1, async, ayeslick, aysha, berndartmueller, bin2chen, bobirichman, brgltd, bulej93, c3phas, carrotsmuggler, cccz, ch13fd357r0y3r, chatch, cryptostellar5, cryptphi, csanuragjain, d3e4, datapunk, delfin454000, dic0de, djxploit, durianSausage, eighty, erictee, exd0tpy, fatherOfBlocks, gogo, got_targ, hansfriese, ignacio, ikbkln, indijanc, innertia, joestakey, karanctf, ladboy233, leosathya, lukris02, martin, medikko, millersplanet, nalus, natzuu, neko_nyaa, neumo, obront, oyc_109, pcarranzav, peanuts, pedr02b2, pedroais, peiw, peritoflores, prasantgupta52, rajatbeladiya, rbserver, reassor, ret2basic, rokinot, romand, rotcivegaf, rvierdiiev, sach1r0, seyni, sikorico, slowmoses, sorrynotsorry, supernova, tibthecat, tnevler, ubermensch, yongskiws, zzykxx, zzzitron
18.8574 USDC - $18.86
Incorrect comments
The comment max supply == 0 means mint at will.
should be maxSupply_ == 0 means mint at will.
The comment However, if both are 0 we might have a valid scenario as well - user just wants to create a token but doesn't want to mint anything
is incorrect. If both maxSupply_
and initialSupply_
are 0 then the user just wants to create a token but doesn't want to mint anything INITIALLY. It does indeed seem that this should be allowed, in which case the entire require-statement at line 27 can be removed.
Â
Compiler version should be fixed
🌟 Selected for report: IllIllI
Also found by: 0v3rf10w, 0x040, 0x1f8b, 0x4non, 0x85102, 0xA5DF, 0xDanielC, 0xNazgul, 0xSmartContract, 0xbepresent, 0xc0ffEE, 0xsam, 2997ms, AkshaySrivastav, Amithuddar, Atarpara, Aymen0909, B2, Bnke0x0, CertoraInc, Chom, ChristianKuri, CodingNameKiki, Deivitto, Diana, DimitarDimitrov, Diraco, Funen, JC, JLevick, JohnSmith, Junnon, KIntern_NA, Lambda, MasterCookie, Matin, Noah3o6, Ocean_Sky, OptimismSec, RaymondFam, Respx, ReyAdmirado, RockingMiles, Rohan16, Rolezn, Ruhum, Saintcode_, Satyam_Sharma, Sm4rty, SnowMan, SooYa, Sta1400, StevenL, Tadashi, Tagir2003, TomJ, Tomio, Tomo, V_B, Waze, WilliamAmbrozic, Yiko, __141345__, a12jmx, adriro, ajtra, ak1, async, aysha, beardofginger, bobirichman, brgltd, bulej93, c3phas, carrotsmuggler, caventa, ch0bu, cryptostellar5, cryptphi, csanuragjain, d3e4, delfin454000, dharma09, djxploit, durianSausage, eighty, emrekocak, erictee, exd0tpy, fatherOfBlocks, francoHacker, gianganhnguyen, gogo, got_targ, hxzy, ignacio, ikbkln, imare, indijanc, jag, jpserrat, karanctf, ladboy233, leosathya, lucacez, lukris02, m9800, malinariy, martin, medikko, mics, millersplanet, mrpathfindr, nalus, natzuu, neko_nyaa, oyc_109, pauliax, peanuts, pedroais, peiw, pfapostol, prasantgupta52, rbserver, ret2basic, rokinot, rotcivegaf, rvierdiiev, sach1r0, samruna, seyni, slowmoses, subtle77, supernova, tgolding55, tibthecat, tnevler, w0Lfrum, yaemsobak, zishansami
9.086 USDC - $9.09
Fixed bytes is cheaper than string
As a rule of thumb, use bytes for arbitrary-length raw byte data and string for arbitrary-length string (UTF-8) data. If you can limit the length to a certain number of bytes, always use one of bytes1 to bytes32 because they are much cheaper.
Instances: https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/token/FullPremintERC20Token.sol#L10 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/token/VariableSupplyERC20Token.sol#L21
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Custom errors are cheaper than require-statements See this. Consider replacing require-statements with a string message with a custom error in an if-revert.
Instances: https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/token/FullPremintERC20Token.sol#L11 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/token/VariableSupplyERC20Token.sol#L27 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/token/VariableSupplyERC20Token.sol#L37 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/token/VariableSupplyERC20Token.sol#L41 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/AccessProtected.sol#L25 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/AccessProtected.sol#L40 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L82 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L107 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L111 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L114 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L115 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L129 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L133 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L136 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L137 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L138 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L255 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L256 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L257 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L261 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L261 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L262 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L263 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L264 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L270 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L295 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L344 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L374 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L402 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L426 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L447 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L449
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Function not called by the contract can be external
instead of public
Â
Comparing to constant bool
Replace _claim.isActive == true
with _claim.isActive
.
Instances: https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/VTVLVesting.sol#L111 https://github.com/code-423n4/2022-09-vtvl/blob/f68b7f3e61dad0d873b5b5a1e8126b839afeab5f/contracts/AccessProtected.sol#L39