From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Peter Jones <[email protected]>
Date: Mon, 21 Mar 2022 16:56:10 -0400
Subject: [PATCH] modules: Don't allocate space for non-allocable sections.

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 <[email protected]>
(cherry picked from commit 03215e342f552396ab08125ea769b1e166417ec1)
(cherry picked from commit 91518751b9bcba078e3f4385f4b2f6c39cab49cd)
---
 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 520126beab..ba1b33c20b 100644
--- a/grub-core/kern/dl.c
+++ b/grub-core/kern/dl.c
@@ -290,6 +290,9 @@ 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;