[PATCH 5.10 028/130] objtool: Extract elf_strtab_concat()

Greg Kroah-Hartman
2022-07-12T18:42:22Z

commit 417a4dc91e559f92404c2544f785b02ce75784c3 upstream.

Create a common helper to append strings to a strtab.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/20210326151259.941474004@infradead.org
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
tools/objtool/elf.c | 60 ++++++++++++++++++++++++++++++++--------------------
1 file changed, 38 insertions(+), 22 deletions(-)

--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -724,13 +724,48 @@ err:
return NULL;
}

+static int elf_add_string(struct elf *elf, struct section *strtab, char *str)
+{
+ Elf_Data *data;
+ Elf_Scn *s;
+ int len;
+
+ if (!strtab)
+ strtab = find_section_by_name(elf, ".strtab");
+ if (!strtab) {
+ WARN("can't find .strtab section");
+ return -1;
+ }
+
+ s = elf_getscn(elf->elf, strtab->idx);
+ if (!s) {
+ WARN_ELF("elf_getscn");
+ return -1;
+ }
+
+ data = elf_newdata(s);
+ if (!data) {
+ WARN_ELF("elf_newdata");
+ return -1;
+ }
+
+ data->d_buf = str;
+ data->d_size = strlen(str) + 1;
+ data->d_align = 1;
+
+ len = strtab->len;
+ strtab->len += data->d_size;
+ strtab->changed = true;
+
+ return len;
+}
+
struct section *elf_create_section(struct elf *elf, const char *name,
unsigned int sh_flags, size_t entsize, int nr)
{
struct section *sec, *shstrtab;
size_t size = entsize * nr;
Elf_Scn *s;
- Elf_Data *data;

sec = malloc(sizeof(*sec));
if (!sec) {
@@ -787,7 +822,6 @@ struct section *elf_create_section(struc
sec->sh.sh_addralign = 1;
sec->sh.sh_flags = SHF_ALLOC | sh_flags;

-
/* Add section name to .shstrtab (or .strtab for Clang) */
shstrtab = find_section_by_name(elf, ".shstrtab");
if (!shstrtab)
@@ -796,27 +830,9 @@ struct section *elf_create_section(struc
WARN("can't find .shstrtab or .strtab section");
return NULL;
}
-
- s = elf_getscn(elf->elf, shstrtab->idx);
- if (!s) {
- WARN_ELF("elf_getscn");
- return NULL;
- }
-
- data = elf_newdata(s);
- if (!data) {
- WARN_ELF("elf_newdata");
+ sec->sh.sh_name = elf_add_string(elf, shstrtab, sec->name);
+ if (sec->sh.sh_name == -1)
return NULL;
- }
-
- data->d_buf = sec->name;
- data->d_size = strlen(name) + 1;
- data->d_align = 1;
-
- sec->sh.sh_name = shstrtab->len;
-
- shstrtab->len += strlen(name) + 1;
- shstrtab->changed = true;

list_add_tail(&sec->list, &elf->sections);
elf_hash_add(elf->section_hash, &sec->hash, sec->idx);