From: B Horn <b@horn.uk>
Date: Sun, 12 May 2024 02:01:40 +0000 (+0100)
Subject: kern/file: Ensure file->data is set
X-Git-Tag: archive/raspbian/2.12-8+rpi1^2~55
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=7973cbca0ee83c711b62ef7ce6537f1913d97902;p=grub2.git

kern/file: Ensure file->data is set

This is to avoid a generic issue were some filesystems would not set
data and also not set a grub_errno. This meant it was possible for many
filesystems to grub_dl_unref() themselves multiple times resulting in
it being possible to unload the filesystems while there were still
references to them, e.g., via a loopback.

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

Gbp-Pq: Topic cve-2025-jan
Gbp-Pq: Name kern-file-Ensure-file-data-is-set.patch
---

diff --git a/grub-core/kern/file.c b/grub-core/kern/file.c
index 7501772..e990507 100644
--- a/grub-core/kern/file.c
+++ b/grub-core/kern/file.c
@@ -114,6 +114,9 @@ grub_file_open (const char *name, enum grub_file_type type)
   if ((file->fs->fs_open) (file, file_name) != GRUB_ERR_NONE)
     goto fail;
 
+  if (file->data == NULL)
+    goto fail;
+
   file->name = grub_strdup (name);
   grub_errno = GRUB_ERR_NONE;