diff --git a/0212-grub-mkconfig-restore-umask-for-grub.cfg.patch b/0212-grub-mkconfig-restore-umask-for-grub.cfg.patch new file mode 100644 index 0000000..d9a8196 --- /dev/null +++ b/0212-grub-mkconfig-restore-umask-for-grub.cfg.patch @@ -0,0 +1,43 @@ +From 3ea051e59e9c0cd79eac7f2e1563606e1e31a530 Mon Sep 17 00:00:00 2001 +From: Michael Chang via Grub-devel +Date: Fri, 3 Dec 2021 16:13:28 +0800 +Subject: [PATCH] grub-mkconfig: restore umask for grub.cfg + +Since commit: + + ab2e53c8a grub-mkconfig: Honor a symlink when generating configuration +by grub-mkconfig + +has inadvertently discarded umask for creating grub.cfg in the process +of grub-mkconfig. The resulting wrong permission (0644) would allow +unprivileged users to read grub's configuration file content. This +presents a low confidentiality risk as grub.cfg may contain non-secured +plain-text passwords. + +This patch restores the missing umask and set the file mode of creation +to 0600 preventing unprivileged access. + +Fixes: CVE-2021-3981 + +Signed-off-by: Michael Chang +--- + util/grub-mkconfig.in | 2 ++ + 1 file changed, 2 insertions(+) + +diff --git a/util/grub-mkconfig.in b/util/grub-mkconfig.in +index f55339a3f..520a672cd 100644 +--- a/util/grub-mkconfig.in ++++ b/util/grub-mkconfig.in +@@ -311,7 +311,9 @@ and /etc/grub.d/* files or please file a bug report with + exit 1 + else + # none of the children aborted with error, install the new grub.cfg ++ oldumask=$(umask); umask 077 + cat ${grub_cfg}.new > ${grub_cfg} ++ umask $oldumask + rm -f ${grub_cfg}.new + fi + fi +-- +2.33.0 + diff --git a/grub.patches b/grub.patches index 4a349cd..b833690 100644 --- a/grub.patches +++ b/grub.patches @@ -209,3 +209,4 @@ Patch0208: 0208-Arm-check-for-the-PE-magic-for-the-compiled-arch.patch Patch0209: 0209-fs-xfs-Fix-unreadable-filesystem-with-v4-superblock.patch Patch0210: 0210-Print-module-name-on-license-check-failure.patch Patch0211: 0211-powerpc-ieee1275-load-grub-at-4MB-not-2MB.patch +Patch0212: 0212-grub-mkconfig-restore-umask-for-grub.cfg.patch diff --git a/grub2.spec b/grub2.spec index 25b2b52..89030ea 100644 --- a/grub2.spec +++ b/grub2.spec @@ -14,7 +14,7 @@ Name: grub2 Epoch: 1 Version: 2.06 -Release: 9%{?dist} +Release: 10%{?dist} Summary: Bootloader with support for Linux, Multiboot and more License: GPLv3+ URL: http://www.gnu.org/software/grub/ @@ -523,6 +523,9 @@ mv ${EFI_HOME}/grub.cfg.stb ${EFI_HOME}/grub.cfg %endif %changelog +* Thu Dec 09 2021 Robbie Harwood - 2.06-10 +- restore umask for grub.cfg (CVE-2021-3981) + * Thu Nov 04 2021 Robbie Harwood - 2.06-9 - Drop UI patches and update provenance information