Check for a branded ELF note when OS/ABI is NONE #1344
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Currently the auditor is only checking for the correct OS/ABI and producing a warning on FreeBSD when it doesn't match. This warning is incorrect on AArch64 though, as FreeBSD instead uses an ELF note to declare the OS/ABI. The change implemented here looks for such a note when the OS/ABI in the ELF header is NONE.
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I haven't looked at the implementation yet, but I want to quickly answer the question
Yeah, the problem is that we don't know (or forgot? who knows) how libraries with the wrong OS/ABI field were generated on FreeBSD. An alternative should be to compile a simple dummy library (something like |
| # On AArch64 and RISC-V, FreeBSD uses an ELF note section to identify itself rather | ||
| # than OS/ABI in the ELF header. In that case, the OS/ABI will be generic Unix (NONE). | ||
| # See https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=252490 and | ||
| # https://github.com/freebsd/freebsd-src/blob/main/lib/csu/common/crtbrand.S |
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| # https://github.com/freebsd/freebsd-src/blob/main/lib/csu/common/crtbrand.S | |
| # https://github.com/freebsd/freebsd-src/blob/3c95262007ef934c9e98b87460a48889bf42c1b9/lib/csu/common/crtbrand.S |
| @@ -39,7 +64,9 @@ function platform_for_object(oh::ObjectHandle) | |||
| end | |||
| end | |||
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| if oh.ei.osabi == ELF.ELFOSABI_LINUX || oh.ei.osabi == ELF.ELFOSABI_NONE | |||
| if oh.ei.osabi == ELF.ELFOSABI_NONE | |||
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Should we just delete platform_for_object since it appears to be unused?
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Sure, I can if you'd like me to.
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Ah rip, the patchelf we ship is old and doesn't have |
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Sigh, never mind the test then, we can't upgrade patchelf because newer version is broken (JuliaPackaging/Yggdrasil#7728 (comment), caused by NixOS/patchelf#492) |
Currently the auditor is only checking for the correct OS/ABI and producing a warning on FreeBSD when it doesn't match. This warning is incorrect on AArch64 though, as FreeBSD instead uses an ELF note to declare the OS/ABI. The change implemented here looks for such a note when the OS/ABI in the ELF header is NONE.
Note that there are no tests added... I'd be interested in any suggestions for how best to test this given that the functions I modified are not currently tested, at least directly (AFAICT).