Hi Anton,
On Wed, 2024-10-23 at 14:14 +0300, [email protected] wrote:
> From: AntonMoryakov <[email protected]>
>
> - Added a check to ensure `arhdr` is not NULL before using it in `strcmp` to
> avoid segmentation fault.
> - This resolves the issue where the pointer returned from `elf_getarhdr` may
> be NULL and causes a crash when dereferenced.
Kind of the same questions/comments as for previous patches. Please
sign your work, keep with current coding style and if you have a
testcase that would be ideal.
> ---
> src/objdump.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/src/objdump.c b/src/objdump.c
> index 1b38da23..33b6fec5 100644
> --- a/src/objdump.c
> +++ b/src/objdump.c
> @@ -313,7 +313,8 @@ handle_ar (int fd, Elf *elf, const char *prefix, const
> char *fname,
> Elf_Arhdr *arhdr = elf_getarhdr (subelf);
>
> /* Skip over the index entries. */
> - if (strcmp (arhdr->ar_name, "/") != 0
> + if (arhdr != NULL
> + && strcmp (arhdr->ar_name, "/") != 0
> && strcmp (arhdr->ar_name, "//") != 0)
> {
> if (elf_kind (subelf) == ELF_K_ELF)
I think it would be better to do a separate check for arhdr being NULL,
that should normally not happen imho. Then do an INTERNAL_ERROR (fname)
to stop processing and report the libelf error. e.g something like:
diff --git a/src/objdump.c b/src/objdump.c
index 1b38da23266d..94cc69cb0f6a 100644
--- a/src/objdump.c
+++ b/src/objdump.c
@@ -311,6 +311,8 @@ handle_ar (int fd, Elf *elf, const char *prefix,
const char *fname,
{
/* The the header for this element. */
Elf_Arhdr *arhdr = elf_getarhdr (subelf);
+ if (ahdr == NULL)
+ INTERNAL_ERROR (fname);
/* Skip over the index entries. */
if (strcmp (arhdr->ar_name, "/") != 0
Cheers,
Mark
