[PATCH v6 03/10] modules: Don't allocate space for non-allocable sections.

[Mate Kukri]

From: Peter Jones <pjones@redhat.com>

Currently when loading grub modules, we allocate space for all sections,
including those without SHF_ALLOC set.  We then copy the sections that
/do/ have SHF_ALLOC set into the allocated memory, leaving some of our
allocation untouched forever.  Additionally, on platforms with GOT
fixups and trampolines, we currently compute alignment round-ups for the
sections and sections with sh_size = 0.

This patch removes the extra space from the allocation computation, and
makes the allocation computation loop skip empty sections as the loading
loop does.

Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Jan Setje-Eilers <jan.setjeeilers@oracle.com>
Signed-off-by: Mate Kukri <mate.kukri@canonical.com>
Reviewed-By: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 grub-core/kern/dl.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c
index 0bf40caa6..37db9fab0 100644
--- a/grub-core/kern/dl.c
+++ b/grub-core/kern/dl.c
@@ -237,6 +237,9 @@ grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e)
        i < e->e_shnum;
        i++, s = (const Elf_Shdr *)((const char *) s + e->e_shentsize))
     {
+      if (s->sh_size == 0 || !(s->sh_flags & SHF_ALLOC))
+       continue;
+
       tsize = ALIGN_UP (tsize, s->sh_addralign) + s->sh_size;
       if (talign < s->sh_addralign)
        talign = s->sh_addralign;
-- 
2.39.2