Adding a new section to an ELF file aborts with Assertion `shdr != NULL'
Sat Sep 4 09:13:33 GMT 2021
Alexander Egorenkov <firstname.lastname@example.org> writes:
> Hi all,
> i'm facing an issue with libelf when i try to add a new section to an
> ELF file.
> How to reproduce the issue:
> 1. Create a simple ELF file with libelf containing only 2 sections, NULL and
> a string table
> 2. Close ELF file
> 3. Reopen the new ELF file in RW mode with libelf
> 4. Add new section with elf_newscn()
> 5. Update ELF with elf_update()
> 6. Assertion appears
> The weird thing is that if i add only a new program segment then
> everything goes well. But as soon as i add a new section, it fails.
> Error message:
> test: elf32_updatenull.c:214: __elf64_updatenull_wrlock: Assertion `shdr
> != NULL' failed.
> Any hint what i'm doing wrong ?
One workaround i found is this:
scn = elf_getscn(elf, 0);
shdr = elf64_getshdr(scn);
It seems that __elf64_updatenull_wrlock() tries to access the section
header of the NULL section.
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