[all-commits] [llvm/llvm-project] 94b085: [sanitizer] use uptr to store the result of intern...

[Enna1 via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 94b0851aad618397f508e56c63c6f928e4e911b9
      https://github.com/llvm/llvm-project/commit/94b0851aad618397f508e56c63c6f928e4e911b9
  Author: Enna1 <xumingjie.enna1 at bytedance.com>
  Date:   2023-08-28 (Mon, 28 Aug 2023)

  Changed paths:
    M compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors_format.inc
    A compiler-rt/test/sanitizer_common/TestCases/vsnprintf.cpp

  Log Message:
  -----------
  [sanitizer] use uptr to store the result of internal_strlen/internal_strnlen in printf_common

The return type of `internal_strlen()` is 'uptr', but in `printf_common()` we store the result of `internal_strlen()` into an 'int' type variable.
When the result value of `internal_strlen()` is larger than the largest possible value of 'int' type, the implicit conversion from 'uptr' to 'int' will change the result value to a negative value.

Without this change, asan reports a false positive negative-size-param in the added testcase.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D157266