This is a note to let you know that I've just added the patch titled
efi: efivars: prevent double registration
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
efi-efivars-prevent-double-registration.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From stable+bounces-25895-greg=kroah.com@xxxxxxxxxxxxxxx Mon Mar 4 12:20:46 2024
From: Ard Biesheuvel <ardb+git@xxxxxxxxxx>
Date: Mon, 4 Mar 2024 12:19:40 +0100
Subject: efi: efivars: prevent double registration
To: stable@xxxxxxxxxxxxxxx
Cc: linux-efi@xxxxxxxxxxxxxxx, Johan Hovold <johan+linaro@xxxxxxxxxx>, Ard Biesheuvel <ardb@xxxxxxxxxx>
Message-ID: <20240304111937.2556102-22-ardb+git@xxxxxxxxxx>
From: Ard Biesheuvel <ardb+git@xxxxxxxxxx>
From: Johan Hovold <johan+linaro@xxxxxxxxxx>
[ Commit 0217a40d7ba6e71d7f3422fbe89b436e8ee7ece7 upstream ]
Add the missing sanity check to efivars_register() so that it is no
longer possible to override an already registered set of efivar ops
(without first deregistering them).
This can help debug initialisation ordering issues where drivers have so
far unknowingly been relying on overriding the generic ops.
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/firmware/efi/vars.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -66,19 +66,28 @@ int efivars_register(struct efivars *efi
const struct efivar_operations *ops,
struct kobject *kobject)
{
+ int rv;
+
if (down_interruptible(&efivars_lock))
return -EINTR;
+ if (__efivars) {
+ pr_warn("efivars already registered\n");
+ rv = -EBUSY;
+ goto out;
+ }
+
efivars->ops = ops;
efivars->kobject = kobject;
__efivars = efivars;
pr_info("Registered efivars operations\n");
-
+ rv = 0;
+out:
up(&efivars_lock);
- return 0;
+ return rv;
}
EXPORT_SYMBOL_GPL(efivars_register);
Patches currently in stable-queue which might be from kroah.com@xxxxxxxxxxxxxxx are
queue-6.1/x86-decompressor-avoid-magic-offsets-for-efi-handover-entrypoint.patch
queue-6.1/x86-efistub-avoid-placing-the-kernel-below-load_physical_addr.patch
queue-6.1/x86-efistub-avoid-legacy-decompressor-when-doing-efi-boot.patch
queue-6.1/x86-efistub-perform-4-5-level-paging-switch-from-the-stub.patch
queue-6.1/x86-boot-rename-conflicting-boot_params-pointer-to-boot_params_ptr.patch
queue-6.1/x86-efistub-perform-snp-feature-test-while-running-in-the-firmware.patch
queue-6.1/x86-efistub-simplify-and-clean-up-handover-entry-code.patch
queue-6.1/efi-libstub-add-memory-attribute-protocol-definitions.patch
queue-6.1/efi-libstub-add-limit-argument-to-efi_random_alloc.patch
queue-6.1/efi-x86-fix-the-missing-kaslr_flag-bit-in-boot_params-hdr.loadflags.patch
queue-6.1/arm64-efi-limit-allocations-to-48-bit-addressable-physical-region.patch
queue-6.1/x86-efistub-prefer-efi-memory-attributes-protocol-over-dxe-services.patch
queue-6.1/efi-efivars-prevent-double-registration.patch
queue-6.1/x86-boot-efistub-assign-global-boot_params-variable.patch
queue-6.1/x86-efistub-clear-bss-in-efi-handover-protocol-entrypoint.patch
queue-6.1/x86-decompressor-factor-out-kernel-decompression-and-relocation.patch
queue-6.1/efi-x86-avoid-physical-kaslr-on-older-dell-systems.patch
