buildroot/boot/grub2/0009-fs-iso9660-Set-a-grub_errno-if-mount-fails.patch

From a0e37c98e6f330110e4009f8e5ba73ca0c2eaff5 Mon Sep 17 00:00:00 2001
From: B Horn <b@horn.uk>
Date: Sun, 12 May 2024 06:37:08 +0100
Subject: [PATCH] fs/iso9660: Set a grub_errno if mount fails

It was possible for a grub_errno to not be set if mount of an ISO 9660
filesystem failed when set_rockridge() returned 0.

This isn't known to be exploitable as the other filesystems due to
filesystem helper checking the requested file type. Though fixing
as a precaution.

Reported-by: B Horn <b@horn.uk>
Signed-off-by: B Horn <b@horn.uk>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Upstream: 965db5970811d18069b34f28f5f31ddadde90a97
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
---
 grub-core/fs/iso9660.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/grub-core/fs/iso9660.c b/grub-core/fs/iso9660.c
index 8c348b59a..8d480e602 100644
--- a/grub-core/fs/iso9660.c
+++ b/grub-core/fs/iso9660.c
@@ -551,6 +551,9 @@ grub_iso9660_mount (grub_disk_t disk)
   return data;
 
  fail:
+  if (grub_errno == GRUB_ERR_NONE)
+    grub_error (GRUB_ERR_BAD_FS, "not a ISO9660 filesystem");
+
   grub_free (data);
   return 0;
 }
-- 
2.50.1