[PATCH 2/6] modpost: refactor namespace_from_kstrtabns() to not hard-code section name

From: Masahiro Yamada
Date: Thu Nov 14 2019 - 12:42:53 EST


Currently, namespace_from_kstrtabns() relies on the fact that
namespace strings are recorded in the __ksymtab_strings section.
Actually, it is coded in include/linux/export.h, but modpost does
not need to hard-code the section name.

Elf_Sym::st_shndx holds the section number of the relevant section.
Using it is a more portable way to find the namespace string.

sym_get_value() takes care of it, so namespace_from_kstrtabns() can
simply wrap it. Delete the unneeded info->ksymtab_strings .

While I was here, I added more 'const' qualifiers to pointers.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

scripts/mod/modpost.c | 10 +++-------
scripts/mod/modpost.h | 1 -
2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index cd885573daaf..d9418c58a8c0 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -356,10 +356,10 @@ static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
return export_unknown;
}

-static const char *namespace_from_kstrtabns(struct elf_info *info,
- Elf_Sym *kstrtabns)
+static const char *namespace_from_kstrtabns(const struct elf_info *info,
+ const Elf_Sym *sym)
{
- char *value = info->ksymtab_strings + kstrtabns->st_value;
+ const char *value = sym_get_data(info, sym);
return value[0] ? value : NULL;
}

@@ -601,10 +601,6 @@ static int parse_elf(struct elf_info *info, const char *filename)
info->export_unused_gpl_sec = i;
else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
info->export_gpl_future_sec = i;
- else if (strcmp(secname, "__ksymtab_strings") == 0)
- info->ksymtab_strings = (void *)hdr +
- sechdrs[i].sh_offset -
- sechdrs[i].sh_addr;

if (sechdrs[i].sh_type == SHT_SYMTAB) {
unsigned int sh_link_idx;
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index fe6652535e4b..64a82d2d85f6 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -143,7 +143,6 @@ struct elf_info {
Elf_Section export_gpl_sec;
Elf_Section export_unused_gpl_sec;
Elf_Section export_gpl_future_sec;
- char *ksymtab_strings;
char *strtab;
char *modinfo;
unsigned int modinfo_len;
--
2.17.1