C++: Taint flow to formatting function return values. #3533
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Strictly speaking, taint should flow from a tainted argument to a formatting function such as
sprintf
to the return value (the number of characters written / error code). This is much less important than the existing flow to the output parameter, but could conceivably come up as allowing a user to control the size of an allocation or something like that.This is consistent with how we handle
strftime
(the only similar case I could find) and is the final part of https://jira.semmle.com/browse/CPP-466 (which I am keen to close).The new test results in
format.cpp
are on lines that look like this: