On Tue, Jun 6, 2023 at 5:31 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
>
> [ Ancient code warning. - dan ]
>
> Hello Quentin Casasnovas,
>
> The patch 52dc0595d540: "modpost: handle relocations mismatch in
> __ex_table." from Apr 13, 2015, leads to the following Smatch static
> checker warning:
>
> ./scripts/mod/modpost.c:1154 is_executable_section()
> warn: array off by one? 'elf->sechdrs[secndx]'
>
> ./scripts/mod/modpost.c
> 1149 static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
> 1150 {
> 1151 if (secndx > elf->num_sections)
> ^^^^^^^^^^^^^^^^^^^^^^^^^^
> I'm not positive, but I think this should be >=.
Ah, right. This is a bug, and your fix is correct.
>
> 1152 return false;
> 1153
> --> 1154 return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;
> ^^^^^^
> out of bounds read.
>
> 1155 }
>
> regards,
> dan carpenter
--
Best Regards
Masahiro Yamada
