kernel/linux.git/drivers/firmware/efi, branch v6.6.39

LoongArch: Fix entry point in kernel image header

2024-06-27T11:49:15+00:00

[ Upstream commit beb2800074c15362cf9f6c7301120910046d6556 ] Currently kernel entry in head.S is in DMW address range, firmware is instructed to jump to this address after loading the kernel image. However kernel should not make any assumption on firmware's DMW setting, thus the entry point should be a physical address falls into direct translation region. Fix by converting entry address to physical and amend entry calculation logic in libstub accordingly. BTW, use ABSOLUTE() to calculate variables to make Clang/LLVM happy. Cc: stable@vger.kernel.org Signed-off-by: Jiaxun Yang Signed-off-by: Huacai Chen Signed-off-by: Sasha Levin

efi/loongarch: Directly position the loaded image file

2024-06-27T11:49:15+00:00

[ Upstream commit 174a0c565cea74a7811ff79fbee1b70247570ade ] The use of the 'kernel_offset' variable to position the image file that has been loaded by UEFI or GRUB is unnecessary, because we can directly position the loaded image file through using the image_base field of the efi_loaded_image struct provided by UEFI. Replace kernel_offset with image_base to position the image file that has been loaded by UEFI or GRUB. Signed-off-by: Wang Yao Signed-off-by: Ard Biesheuvel Stable-dep-of: beb2800074c1 ("LoongArch: Fix entry point in kernel image header") Signed-off-by: Sasha Levin

efi/x86: Free EFI memory map only when installing a new one.

2024-06-27T11:49:13+00:00

commit 75dde792d6f6c2d0af50278bd374bf0c512fe196 upstream. The logic in __efi_memmap_init() is shared between two different execution flows: - mapping the EFI memory map early or late into the kernel VA space, so that its entries can be accessed; - the x86 specific cloning of the EFI memory map in order to insert new entries that are created as a result of making a memory reservation via a call to efi_mem_reserve(). In the former case, the underlying memory containing the kernel's view of the EFI memory map (which may be heavily modified by the kernel itself on x86) is not modified at all, and the only thing that changes is the virtual mapping of this memory, which is different between early and late boot. In the latter case, an entirely new allocation is created that carries a new, updated version of the kernel's view of the EFI memory map. When installing this new version, the old version will no longer be referenced, and if the memory was allocated by the kernel, it will leak unless it gets freed. The logic that implements this freeing currently lives on the code path that is shared between these two use cases, but it should only apply to the latter. So move it to the correct spot. While at it, drop the dummy definition for non-x86 architectures, as that is no longer needed. Cc: Fixes: f0ef6523475f ("efi: Fix efi_memmap_alloc() leaks") Tested-by: Ashish Kalra Link: https://lore.kernel.org/all/36ad5079-4326-45ed-85f6-928ff76483d3@amd.com Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

efi: libstub: only free priv.runtime_map when allocated

2024-06-12T09:13:01+00:00

commit 4b2543f7e1e6b91cfc8dd1696e3cdf01c3ac8974 upstream. priv.runtime_map is only allocated when efi_novamap is not set. Otherwise, it is an uninitialized value. In the error path, it is freed unconditionally. Avoid passing an uninitialized value to free_pool. Free priv.runtime_map only when it was allocated. This bug was discovered and resolved using Coverity Static Analysis Security Testing (SAST) by Synopsys, Inc. Fixes: f80d26043af9 ("efi: libstub: avoid efi_get_memory_map() for allocating the virt map") Cc: Signed-off-by: Hagar Hemdan Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

x86/efistub: Omit physical KASLR when memory reservations exist

2024-06-12T09:13:01+00:00

commit 15aa8fb852f995dd234a57f12dfb989044968bb6 upstream. The legacy decompressor has elaborate logic to ensure that the randomized physical placement of the decompressed kernel image does not conflict with any memory reservations, including ones specified on the command line using mem=, memmap=, efi_fake_mem= or hugepages=, which are taken into account by the kernel proper at a later stage. When booting in EFI mode, it is the firmware's job to ensure that the chosen range does not conflict with any memory reservations that it knows about, and this is trivially achieved by using the firmware's memory allocation APIs. That leaves reservations specified on the command line, though, which the firmware knows nothing about, as these regions have no other special significance to the platform. Since commit a1b87d54f4e4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot") these reservations are not taken into account when randomizing the physical placement, which may result in conflicts where the memory cannot be reserved by the kernel proper because its own executable image resides there. To avoid having to duplicate or reuse the existing complicated logic, disable physical KASLR entirely when such overrides are specified. These are mostly diagnostic tools or niche features, and physical KASLR (as opposed to virtual KASLR, which is much more important as it affects the memory addresses observed by code executing in the kernel) is something we can live without. Closes: https://lkml.kernel.org/r/FA5F6719-8824-4B04-803E-82990E65E627%40akamai.com Reported-by: Ben Chaney Fixes: a1b87d54f4e4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot") Cc: # v6.1+ Reviewed-by: Kees Cook Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

x86/boot: Move mem_encrypt= parsing to the decompressor

2024-04-10T14:36:07+00:00

commit cd0d9d92c8bb46e77de62efd7df13069ddd61e7d upstream. The early SME/SEV code parses the command line very early, in order to decide whether or not memory encryption should be enabled, which needs to occur even before the initial page tables are created. This is problematic for a number of reasons: - this early code runs from the 1:1 mapping provided by the decompressor or firmware, which uses a different translation than the one assumed by the linker, and so the code needs to be built in a special way; - parsing external input while the entire kernel image is still mapped writable is a bad idea in general, and really does not belong in security minded code; - the current code ignores the built-in command line entirely (although this appears to be the case for the entire decompressor) Given that the decompressor/EFI stub is an intrinsic part of the x86 bootable kernel image, move the command line parsing there and out of the core kernel. This removes the need to build lib/cmdline.o in a special way, or to use RIP-relative LEA instructions in inline asm blocks. This involves a new xloadflag in the setup header to indicate that mem_encrypt=on appeared on the kernel command line. Signed-off-by: Ard Biesheuvel Signed-off-by: Borislav Petkov (AMD) Tested-by: Tom Lendacky Link: https://lore.kernel.org/r/20240227151907.387873-17-ardb+git@google.com Signed-off-by: Greg Kroah-Hartman

x86/efistub: Remap kernel text read-only before dropping NX attribute

2024-04-10T14:36:07+00:00

commit 9c55461040a9264b7e44444c53d26480b438eda6 upstream. Currently, the EFI stub invokes the EFI memory attributes protocol to strip any NX restrictions from the entire loaded kernel, resulting in all code and data being mapped read-write-execute. The point of the EFI memory attributes protocol is to remove the need for all memory allocations to be mapped with both write and execute permissions by default, and make it the OS loader's responsibility to transition data mappings to code mappings where appropriate. Even though the UEFI specification does not appear to leave room for denying memory attribute changes based on security policy, let's be cautious and avoid relying on the ability to create read-write-execute mappings. This is trivially achievable, given that the amount of kernel code executing via the firmware's 1:1 mapping is rather small and limited to the .head.text region. So let's drop the NX restrictions only on that subregion, but not before remapping it as read-only first. Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

efi/libstub: Add generic support for parsing mem_encrypt=

2024-04-10T14:36:07+00:00

commit 7205f06e847422b66c1506eee01b9998ffc75d76 upstream. Parse the mem_encrypt= command line parameter from the EFI stub if CONFIG_ARCH_HAS_MEM_ENCRYPT=y, so that it can be passed to the early boot code by the arch code in the stub. This avoids the need for the core kernel to do any string parsing very early in the boot. Signed-off-by: Ard Biesheuvel Signed-off-by: Borislav Petkov (AMD) Tested-by: Tom Lendacky Link: https://lore.kernel.org/r/20240227151907.387873-16-ardb+git@google.com Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

x86/efistub: Reinstate soft limit for initrd loading

2024-04-03T13:28:53+00:00

commit decd347c2a75d32984beb8807d470b763a53b542 upstream. Commit 8117961d98fb2 ("x86/efi: Disregard setup header of loaded image") dropped the memcopy of the image's setup header into the boot_params struct provided to the core kernel, on the basis that EFI boot does not need it and should rely only on a single protocol to interface with the boot chain. It is also a prerequisite for being able to increase the section alignment to 4k, which is needed to enable memory protections when running in the boot services. So only the setup_header fields that matter to the core kernel are populated explicitly, and everything else is ignored. One thing was overlooked, though: the initrd_addr_max field in the setup_header is not used by the core kernel, but it is used by the EFI stub itself when it loads the initrd, where its default value of INT_MAX is used as the soft limit for memory allocation. This means that, in the old situation, the initrd was virtually always loaded in the lower 2G of memory, but now, due to initrd_addr_max being 0x0, the initrd may end up anywhere in memory. This should not be an issue principle, as most systems can deal with this fine. However, it does appear to tickle some problems in older UEFI implementations, where the memory ends up being corrupted, resulting in errors when unpacking the initramfs. So set the initrd_addr_max field to INT_MAX like it was before. Fixes: 8117961d98fb2 ("x86/efi: Disregard setup header of loaded image") Reported-by: Radek Podgorny Closes: https://lore.kernel.org/all/a99a831a-8ad5-4cb0-bff9-be637311f771@podgorny.cz Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

efi/libstub: Cast away type warning in use of max()

2024-04-03T13:28:53+00:00

commit 61d130f261a3c15ae2c4b6f3ac3517d5d5b78855 upstream. Avoid a type mismatch warning in max() by switching to max_t() and providing the type explicitly. Fixes: 3cb4a4827596abc82e ("efi/libstub: fix efi_random_alloc() ...") Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman