Re: [RFC PATCH 01/11] modpost: Support >64K sections

Kees Cook
2020-02-06T12:38:57Z

On Wed, Feb 05, 2020 at 02:39:40PM -0800, Kristen Carlson Accardi wrote:
> According to the ELF specification, if the value of st_shndx
> contains SH_XINDEX, the actual section header index is too
> large to fit in the st_shndx field and you should use the
> value out of the SHT_SYMTAB_SHNDX section instead. This table
> was already being parsed and saved into symtab_shndx_start, however
> it was not being used, causing segfaults when the number of
> sections is greater than 64K. Check the st_shndx field for
> SHN_XINDEX prior to using.
>
> Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>

Looking at "readelf" output continues to make me laugh. :)

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

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Kees Cook