Replace more strcpy with safe string copy

[am11]

Follow up #130547.

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[jkotas]

What guarantees that parent_directory_end has enough space? This pattern is likely to trigger static analyzers.

(not commenting on all places with this issue)

[am11]

It's same guarantees as before; none.

[jkotas]

The PR title is "Replace more strcpy with safe string copy". Why is this safe string copy then?

[am11]

strcpy -> memcpy/strcpy_s, because strcpy is being flagged by clang on OpenBSD warning: strcpy() is almost always misused, please use strlcpy().

[MichalStrehovsky]

I think Jan's point is that if we're changing this code at all, we should change it to something better, not to something that has the same problem and is somewhat harder to read than the original.

[am11]

Not sure how it is harder to read than original given #130547 is merged?

[jkotas]

I was fine with #130547 since it was an open-coded strdup, no length arithmetic, length is computed on one line and used a few lines later in a very straightforward way. In hindsight, I should have suggested to just use strdup instead of open coding it. We use strdup in number of other places. Could you please replace it with strdup as part of these changes?

This code is not a straightforward like that.

We have SafeStringCopy in pal_utilities.h to solve this problem. Can we promote it or some variant of it to be usable everywhere? Would it be possible to standardize on strcpy_s and polyfill strcpy_s when it is not available - do we build on any platforms like that?

[am11]

BA failure is #131256.

[Copilot]

Pull request overview

This PR continues the effort to eliminate strcpy usage across CoreCLR, NativeAOT, and related tools by replacing it with length-aware copies (primarily memcpy) and minor refactors to compute/carry explicit buffer lengths.

Changes:

• Replaced multiple strcpy call sites with memcpy (often using strlen(...) + 1) across VM/JIT/GC/NativeAOT/host/tooling code.
• Introduced explicit length variables in a few places to make copy sizes clearer and avoid repeated strlen in allocation/copy sequences.
• Added a couple of small robustness tweaks (e.g., guarding malloc results before copying in corerun.cpp).

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/coreclr/vm/gdbjit.cpp	Replaces strcpy with memcpy in GDB JIT debug-info string materialization paths.
src/coreclr/utilcode/debug.cpp	Replaces strcpy with memcpy when building the assert expression+stacktrace display buffer.
src/coreclr/utilcode/check.cpp	Uses memcpy for copying dynamically allocated CHECK failure messages.
src/coreclr/nativeaot/Runtime/unix/PalUnix.cpp	Uses computed length + memcpy in PalCopyTCharAsChar.
src/coreclr/nativeaot/Runtime/unix/cgroupcpu.cpp	Reworks cgroup path construction to use explicit lengths and memcpy instead of strcpy/strcat.
src/coreclr/nativeaot/Runtime/RhConfig.cpp	Refactors env-var name construction and switches embedded string copies to memcpy.
src/coreclr/nativeaot/Runtime/clrgc.enabled.cpp	Replaces strcpy concatenation with length-based memcpy copies.
src/coreclr/jit/fgdiagnostic.cpp	Replaces strcpy with memcpy in escape-substitution copying.
src/coreclr/interpreter/methodset.cpp	Copies config string via memcpy instead of strcpy.
src/coreclr/inc/outstring.h	Updates <string.h> include comment (no longer calls out strcpy).
src/coreclr/ildasm/dres.cpp	Replaces strcat/strcpy usage with manual memcpy for indentation/string building in resource dumping.
src/coreclr/ilasm/method.hpp	Updates commented-out code to reference strcpy_s.
src/coreclr/hosts/corerun/corerun.cpp	Uses length-based memcpy and guards malloc before copying core paths.
src/coreclr/gc/unix/cgroup.cpp	Uses mount-length caching + memcpy for initial copy and replaces a strcpy with memcpy.

[janvorli]

Do we gain anything here when the source is a string constant?