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DoS unexpected revert with vector

What it does​

Checks for array pushes without access control.

Why is this bad?​

Arrays have a maximum size according to the storage cell. If the array is full, the push will revert. This can be used to prevent the execution of a function.

Known problems​

If the owner validation is performed in an auxiliary function, the warning will be shown, resulting in a false positive.

Example​

if self.votes.contains(candidate) {
    Err(Errors::CandidateAlreadyAdded)
} else {
    self.candidates.push(candidate); // Where candidates: Vec<AccountId>
    self.votes.insert(candidate, &0);
    Ok(())
}

Use instead:

if self.votes.contains(candidate) {
    Err(Errors::CandidateAlreadyAdded)
} else {
    self.candidates.insert(self.total_candidates, &candidate); // Where candidates: Mapping<u64, AccountId>
    self.total_candidates += 1;
    self.votes.insert(candidate, &0);
    Ok(())
}

Implementation​

The detector's implementation can be found at this link.