[Elftoolchain-developers] (no subject)

[Michael F. <mf...@mf...>]

Hi,

I'm looking for some advice for an issue I hit with some recent
changes to Linux objtool.

Since [0], objtool calls gelf_update_rel[a] to write relocations to
newly created sections rather than writing to a raw array of GElf_Rel
itself. However, the section header is not updated until later when
the ELF file is written back to disk.

It appears that elftoolchain has a check[1] in gelf_update_rel[a] to
make sure that the section header corresponding to the GElf_Data has
the appropriate type, and it fails if not.

Is this a bug in objtool using the libelf API incorrectly, or is
elftoolchain being a bit too eager in its checks? Perhaps it could
skip the check if sh_type == SHT_NULL?

Thanks for any help!

[0] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a1a664ece586457e9f7652b0bc5b08386259e358
[1] https://sourceforge.net/p/elftoolchain/code/HEAD/tree/trunk/libelf/gelf_rela.c#l69