search

checkedc / checkedc-llvm-project

This was a fork of Checked C clang used from 2021-2024. The changes have been merged into the original Checked C clang repo, which is now at https://github.com/checkedc/checkedc-clang.
https://www.checkedc.org
13 stars 19 forks source link

Consider emitting warnings for uses of pointers that violate their bounds-safe interfaces #1158

Open secure-sw-dev-bot opened 2 years ago

secure-sw-dev-bot commented 2 years ago

This issue was copied from https://github.com/microsoft/checkedc-clang/issues/1159

In the future, we may want to consider warning the user if we can detect that the user of a pointer with a bounds-safe interface does not satisfy its bounds-safe interface. For example:

void f(int *p : itype(_Array_ptr<int>),
       int *q : bounds(unknown),
       int *r : count(2),
       int *s : count(1),
       int *t : itype(_Ptr<int>)) {
  // p has implicit declared bounds of bounds(unknown). p should not be dereferenced.
  *p;

  // q has explicit declared bounds of bounds(unknown). This is ok.
  *q;

  // The bounds of s are too small for the declared bounds of r.
  // This could be a bug in the user's chosen itype bounds.
  r = s;

  // Pointer arithmetic is not allowed on _Ptrs. The could be a bug in the user's chosen itype.
  t = t + 1;
}