fortify-headers/tests/test_strncpy_overwrite_under.c, branch experimentalStandalone portable header-based implementation of FORTIFY_SOURCE=3
http://git.dustri.org/fortify-headers/atom?h=experimental2024-10-10T13:50:40ZFix a crash in strncpy/stpncpy2024-10-10T13:50:40Zjvoisin2024-10-10T13:50:40Zurn:sha1:e2cfd2879a15db00dfa9a42eeb1baaef6a930aff
```
Core was generated by `scripts/mod/modpost -M -m -o Module.symvers -n -T modules.order vmlinux.o'.
Program terminated with signal SIGSEGV, Segmentation fault.
warning: 17 src/string/strlen.c: No such file or directory
(gdb) bt
```
> I think strncpy logic is broken: `__fh_size_t max_len_s = strlen(__s);` may try read past `size_t __n`.
> Create a buf without any trailing `\0`, do `strncpy(dest, buf, sizeof(buf));`, it should work, since `strncpy` will stop at `sizeof buf`
> but the current fority-headers implementation will do `strlen(buf)`, which will go boom when it is not terminated with \0
Reported-by: ncopa
Re-enable previously disabled overlap checks2023-12-28T15:13:37Zjvoisin2023-12-27T16:07:32Zurn:sha1:22a8094b41b2606084dc0c0c70487e5ed0fcb652
They were previously disabled in 80a83a5
Don't check for overlapping in strncpy/stpncpy for now2023-12-27T15:06:59Zjvoisin2023-12-27T11:36:47Zurn:sha1:80a83a56b52e833e6d3afec4d0723d7625d52cee
They check overlap across the whole range of the given length, but
the given length is not what will actually be copied, rather it's
the maximum length (if src is shorter, only length of src will be
copied). This triggers false positives and traps where it shouldn't
(e.g. in ICU tests).
Reported-by: q66
Add tests for strncpy and handle overlapping buffers there2023-06-14T12:59:11Zjvoisin2023-06-14T12:59:11Zurn:sha1:cb1ce9e1815a492de0f13c2b046b8472024b9f6d