[PATCH 1/2] elf_symtab: Add support for SHN_XINDEX index to elf_section_by_name

[Jiri Olsa]

In case the elf's header e_shstrndx contains SHN_XINDEX,
we need to call elf_getshdrstrndx to get the proper
string table index.

Acked-by: Andrii Nakryiko <and...@kernel.org>
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
 dutil.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/dutil.c b/dutil.c
index 7b667647420f..11fb7202049c 100644
--- a/dutil.c
+++ b/dutil.c
@@ -179,12 +179,18 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 {
        Elf_Scn *sec = NULL;
        size_t cnt = 1;
+       size_t str_idx;
+
+       if (elf_getshdrstrndx(elf, &str_idx))
+               return NULL;
 
        while ((sec = elf_nextscn(elf, sec)) != NULL) {
                char *str;
 
                gelf_getshdr(sec, shp);
-               str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
+               str = elf_strptr(elf, str_idx, shp->sh_name);
+               if (!str)
+                       return NULL;
                if (!strcmp(name, str)) {
                        if (index)
                                *index = cnt;
-- 
2.26.2