From: B Horn <b@horn.uk>
Date: Thu, 7 Nov 2024 06:00:36 +0000 (+0000)
Subject: kern/dl: Check for the SHF_INFO_LINK flag in grub_dl_relocate_symbols()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=98ad84328dcabfa603dcf5bd217570aa6b4bdd99;p=thirdparty%2Fgrub.git

kern/dl: Check for the SHF_INFO_LINK flag in grub_dl_relocate_symbols()

The grub_dl_relocate_symbols() iterates through the sections in
an ELF looking for relocation sections. According to the spec [1]
the SHF_INFO_LINK flag should be set if the sh_info field is meant
to be a section index.

[1] https://refspecs.linuxbase.org/elf/gabi4+/ch4.sheader.html

Reported-by: B Horn <b@horn.uk>
Signed-off-by: B Horn <b@horn.uk>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---

diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c
index acc6ccad6..de8c3aa8d 100644
--- a/grub-core/kern/dl.c
+++ b/grub-core/kern/dl.c
@@ -623,6 +623,9 @@ grub_dl_relocate_symbols (grub_dl_t mod, void *ehdr)
 	grub_dl_segment_t seg;
 	grub_err_t err;
 
+	if (!(s->sh_flags & SHF_INFO_LINK))
+	  continue;
+
 	/* Find the target segment.  */
 	for (seg = mod->segment; seg; seg = seg->next)
 	  if (seg->section == s->sh_info)