File pr33457.diff of Package binutils
commit 9ca499644a21ceb3f946d1c179c38a83be084490
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Thu Sep 18 16:59:25 2025 -0700
elf: Don't match corrupt section header in linker input
Don't swap in nor match corrupt section header in linker input to avoid
linker crash later.
PR ld/33457
* elfcode.h (elf_swap_shdr_in): Changed to return bool. Return
false for corrupt section header in linker input.
(elf_object_p): Reject if elf_swap_shdr_in returns false.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
diff --git a/bfd/elfcode.h b/bfd/elfcode.h
index 9c65852e103..5224a1abee6 100644
--- a/bfd/elfcode.h
+++ b/bfd/elfcode.h
@@ -311,7 +311,7 @@ elf_swap_ehdr_out (bfd *abfd,
/* Translate an ELF section header table entry in external format into an
ELF section header table entry in internal format. */
-static void
+static bool
elf_swap_shdr_in (bfd *abfd,
const Elf_External_Shdr *src,
Elf_Internal_Shdr *dst)
@@ -341,6 +341,9 @@ elf_swap_shdr_in (bfd *abfd,
{
_bfd_error_handler (_("warning: %pB has a section "
"extending past end of file"), abfd);
+ /* PR ld/33457: Don't match corrupt section header. */
+ if (abfd->is_linker_input)
+ return false;
abfd->read_only = 1;
}
}
@@ -350,6 +353,7 @@ elf_swap_shdr_in (bfd *abfd,
dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize);
dst->bfd_section = NULL;
dst->contents = NULL;
+ return true;
}
/* Translate an ELF section header table entry in internal format into an
@@ -642,9 +646,9 @@ elf_object_p (bfd *abfd)
/* Read the first section header at index 0, and convert to internal
form. */
- if (bfd_read (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
+ if (bfd_read (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)
+ || !elf_swap_shdr_in (abfd, &x_shdr, &i_shdr))
goto got_no_match;
- elf_swap_shdr_in (abfd, &x_shdr, &i_shdr);
/* If the section count is zero, the actual count is in the first
section header. */
@@ -730,9 +734,9 @@ elf_object_p (bfd *abfd)
to internal form. */
for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++)
{
- if (bfd_read (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
+ if (bfd_read (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr)
+ || !elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex))
goto got_no_match;
- elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex);
/* Sanity check sh_link and sh_info. */
if (i_shdrp[shindex].sh_link >= num_sec)