aboutsummaryrefslogtreecommitdiff
path: root/drivers/firmware/efi
AgeCommit message (Collapse)AuthorFilesLines
2022-11-22efi: random: refresh non-volatile random seed when RNG is initializedJason A. Donenfeld1-0/+19
EFI has a rather unique benefit that it has access to some limited non-volatile storage, where the kernel can store a random seed. Register a notification for when the RNG is initialized, and at that point, store a new random seed. Reviewed-by: Ard Biesheuvel <[email protected]> Signed-off-by: Jason A. Donenfeld <[email protected]>
2022-11-18efi: random: combine bootloader provided RNG seed with RNG protocol outputArd Biesheuvel3-8/+40
Instead of blindly creating the EFI random seed configuration table if the RNG protocol is implemented and works, check whether such a EFI configuration table was provided by an earlier boot stage and if so, concatenate the existing and the new seeds, leaving it up to the core code to mix it in and credit it the way it sees fit. This can be used for, e.g., systemd-boot, to pass an additional seed to Linux in a way that can be consumed by the kernel very early. In that case, the following definitions should be used to pass the seed to the EFI stub: struct linux_efi_random_seed { u32 size; // of the 'seed' array in bytes u8 seed[]; }; The memory for the struct must be allocated as EFI_ACPI_RECLAIM_MEMORY pool memory, and the address of the struct in memory should be installed as a EFI configuration table using the following GUID: LINUX_EFI_RANDOM_SEED_TABLE_GUID 1ce1e5bc-7ceb-42f2-81e5-8aadf180f57b Note that doing so is safe even on kernels that were built without this patch applied, but the seed will simply be overwritten with a seed derived from the EFI RNG protocol, if available. The recommended seed size is 32 bytes, and seeds larger than 512 bytes are considered corrupted and ignored entirely. In order to preserve forward secrecy, seeds from previous bootloaders are memzero'd out, and in order to preserve memory, those older seeds are also freed from memory. Freeing from memory without first memzeroing is not safe to do, as it's possible that nothing else will ever overwrite those pages used by EFI. Reviewed-by: Jason A. Donenfeld <[email protected]> [ardb: incorporate Jason's followup changes to extend the maximum seed size on the consumer end, memzero() it and drop a needless printk] Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi/cper, cxl: Decode CXL Error LogSmita Koralahalli1-0/+27
Print the CXL Error Log field as found in CXL Protocol Error Section. The CXL RAS Capability structure will be reused by OS First Handling and the duplication/appropriate placement will be addressed eventually. Signed-off-by: Smita Koralahalli <[email protected]> Reviewed-by: Jonathan Cameron <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi/cper, cxl: Decode CXL Protocol Error SectionSmita Koralahalli4-1/+228
Add support for decoding CXL Protocol Error Section as defined in UEFI 2.10 Section N.2.13. Do the section decoding in a new cper_cxl.c file. This new file will be used in the future for more CXL CPERs decode support. Add this to the existing UEFI_CPER config. Signed-off-by: Smita Koralahalli <[email protected]> Reviewed-by: Jonathan Cameron <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: libstub: fix efi_load_initrd_dev_path() kernel-doc commentJialin Zhang1-2/+2
commit f4dc7fffa987 ("efi: libstub: unify initrd loading between architectures") merge the first and the second parameters into a struct without updating the kernel-doc. Let's fix it. Signed-off-by: Jialin Zhang <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: x86: Move EFI runtime map sysfs code to arch/x86Ard Biesheuvel4-209/+1
The EFI runtime map code is only wired up on x86, which is the only architecture that has a need for it in its implementation of kexec. So let's move this code under arch/x86 and drop all references to it from generic code. To ensure that the efi_runtime_map_init() is invoked at the appropriate time use a 'sync' subsys_initcall() that will be called right after the EFI initcall made from generic code where the original invocation of efi_runtime_map_init() resided. Signed-off-by: Ard Biesheuvel <[email protected]> Reviewed-by: Dave Young <[email protected]>
2022-11-18efi: runtime-maps: Clarify purpose and enable by default for kexecArd Biesheuvel1-6/+6
The current Kconfig logic for CONFIG_EFI_RUNTIME_MAPS does not convey that without it, a kexec kernel is not able to boot in EFI mode at all. So clarify this, and make the option only configurable via the menu system if CONFIG_EXPERT is set. Signed-off-by: Ard Biesheuvel <[email protected]> Reviewed-by: Dave Young <[email protected]>
2022-11-18efi: pstore: Add module parameter for setting the record sizeGuilherme G. Piccoli1-6/+17
By default, the efi-pstore backend hardcode the UEFI variable size as 1024 bytes. The historical reasons for that were discussed by Ard in threads [0][1]: "there is some cargo cult from prehistoric EFI times going on here, it seems. Or maybe just misinterpretation of the maximum size for the variable *name* vs the variable itself.". "OVMF has OvmfPkg/OvmfPkgX64.dsc: gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x2000 OvmfPkg/OvmfPkgX64.dsc: gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x8400 where the first one is without secure boot and the second with secure boot. Interestingly, the default is gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize|0x400 so this is probably where this 1k number comes from." With that, and since there is not such a limit in the UEFI spec, we have the confidence to hereby add a module parameter to enable advanced users to change the UEFI record size for efi-pstore data collection, this way allowing a much easier reading of the collected log, which wouldn't be scattered anymore among many small files. Through empirical analysis we observed that extreme low values (like 8 bytes) could eventually cause writing issues, so given that and the OVMF default discussed, we limited the minimum value to 1024 bytes, which also is still the default. [0] https://lore.kernel.org/lkml/CAMj1kXF4UyRMh2Y_KakeNBHvkHhTtavASTAxXinDO1rhPe_wYg@mail.gmail.com/ [1] https://lore.kernel.org/lkml/CAMj1kXFy-2KddGu+dgebAdU9v2sindxVoiHLWuVhqYw+R=kqng@mail.gmail.com/ Signed-off-by: Guilherme G. Piccoli <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: xen: Set EFI_PARAVIRT for Xen dom0 boot on all architecturesArd Biesheuvel2-3/+4
Currently, the EFI_PARAVIRT flag is only used by Xen dom0 boot on x86, even though other architectures also support pseudo-EFI boot, where the core kernel is invoked directly and provided with a set of data tables that resemble the ones constructed by the EFI stub, which never actually runs in that case. Let's fix this inconsistency, and always set this flag when booting dom0 via the EFI boot path. Note that Xen on x86 does not provide the EFI memory map in this case, whereas other architectures do, so move the associated EFI_PARAVIRT check into the x86 platform code. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: memmap: Move manipulation routines into x86 arch treeArd Biesheuvel1-230/+10
The EFI memory map is a description of the memory layout as provided by the firmware, and only x86 manipulates it in various different ways for its own memory bookkeeping. So let's move the memmap routines that are only used by x86 into the x86 arch tree. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: memmap: Move EFI fake memmap support into x86 arch treeArd Biesheuvel5-235/+0
The EFI fake memmap support is specific to x86, which manipulates the EFI memory map in various different ways after receiving it from the EFI stub. On other architectures, we have managed to push back on this, and the EFI memory map is kept pristine. So let's move the fake memmap code into the x86 arch tree, where it arguably belongs. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: libstub: Undeprecate the command line initrd loaderArd Biesheuvel1-5/+8
The initrd= command line loader can be useful for development, but it was limited to loading files from the same file system as the loaded kernel (and it didn't work on x86 mixed mode). As both issues have been fixed, and the initrd= can now be used with files residing on any simple file system exposed by the EFI firmware, let's permit it to be enabled on RISC-V and LoongArch, which did not support it up to this point. Note that LoadFile2 remains the preferred option, as it is much simpler to use and implement, but generic loaders (including the UEFI shell) may not implement this so there, initrd= can now be used as well (if enabled in the build) Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: libstub: Add mixed mode support to command line initrd loaderArd Biesheuvel3-43/+72
Now that we have support for calling protocols that need additional marshalling for mixed mode, wire up the initrd command line loader. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: libstub: Permit mixed mode return types other than efi_status_tArd Biesheuvel1-6/+14
Rework the EFI stub macro wrappers around protocol method calls and other indirect calls in order to allow return types other than efi_status_t. This means the widening should be conditional on whether or not the return type is efi_status_t, and should be omitted otherwise. Also, switch to _Generic() to implement the type based compile time conditionals, which is more concise, and distinguishes between efi_status_t and u64 properly. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: libstub: Implement devicepath support for initrd commandline loaderArd Biesheuvel2-12/+81
Currently, the initrd= command line option to the EFI stub only supports loading files that reside on the same volume as the loaded image, which is not workable for loaders like GRUB that don't even implement the volume abstraction (EFI_SIMPLE_FILE_SYSTEM_PROTOCOL), and load the kernel from an anonymous buffer in memory. For this reason, another method was devised that relies on the LoadFile2 protocol. However, the command line loader is rather useful when using the UEFI shell or other generic loaders that have no awareness of Linux specific protocols so let's make it a bit more flexible, by permitting textual device paths to be provided to initrd= as well, provided that they refer to a file hosted on a EFI_SIMPLE_FILE_SYSTEM_PROTOCOL volume. E.g., initrd=PciRoot(0x0)/Pci(0x3,0x0)/HD(1,MBR,0xBE1AFDFA,0x3F,0xFBFC1)/rootfs.cpio.gz Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18efi: libstub: use EFI_LOADER_CODE region when moving the kernel in memoryArd Biesheuvel5-9/+16
The EFI spec is not very clear about which permissions are being given when allocating pages of a certain type. However, it is quite obvious that EFI_LOADER_CODE is more likely to permit execution than EFI_LOADER_DATA, which becomes relevant once we permit booting the kernel proper with the firmware's 1:1 mapping still active. Ostensibly, recent systems such as the Surface Pro X grant executable permissions to EFI_LOADER_CODE regions but not EFI_LOADER_DATA regions. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-18Merge tag 'efi-zboot-direct-for-v6.2' into efi/nextArd Biesheuvel23-777/+925
2022-11-10arm64: efi: Force the use of SetVirtualAddressMap() on Altra machinesArd Biesheuvel4-2/+93
Ampere Altra machines are reported to misbehave when the SetTime() EFI runtime service is called after ExitBootServices() but before calling SetVirtualAddressMap(). Given that the latter is horrid, pointless and explicitly documented as optional by the EFI spec, we no longer invoke it at boot if the configured size of the VA space guarantees that the EFI runtime memory regions can remain mapped 1:1 like they are at boot time. On Ampere Altra machines, this results in SetTime() calls issued by the rtc-efi driver triggering synchronous exceptions during boot. We can now recover from those without bringing down the system entirely, due to commit 23715a26c8d81291 ("arm64: efi: Recover from synchronous exceptions occurring in firmware"). However, it would be better to avoid the issue entirely, given that the firmware appears to remain in a funny state after this. So attempt to identify these machines based on the 'family' field in the type #1 SMBIOS record, and call SetVirtualAddressMap() unconditionally in that case. Tested-by: Alexandru Elisei <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09arm64: unwind: add asynchronous unwind tables to kernel and modulesArd Biesheuvel1-0/+1
Enable asynchronous unwind table generation for both the core kernel as well as modules, and emit the resulting .eh_frame sections as init code so we can use the unwind directives for code patching at boot or module load time. This will be used by dynamic shadow call stack support, which will rely on code patching rather than compiler codegen to emit the shadow call stack push and pop instructions. Signed-off-by: Ard Biesheuvel <[email protected]> Reviewed-by: Nick Desaulniers <[email protected]> Reviewed-by: Sami Tolvanen <[email protected]> Tested-by: Sami Tolvanen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Will Deacon <[email protected]>
2022-11-09efi: libstub: Merge zboot decompressor with the ordinary stubArd Biesheuvel2-228/+74
Even though our EFI zboot decompressor is pedantically spec compliant and idiomatic for EFI image loaders, calling LoadImage() and StartImage() for the nested image is a bit of a burden. Not only does it create workflow issues for the distros (as both the inner and outer PE/COFF images need to be signed for secure boot), it also copies the image around in memory numerous times: - first, the image is decompressed into a buffer; - the buffer is consumed by LoadImage(), which copies the sections into a newly allocated memory region to hold the executable image; - once the EFI stub is invoked by StartImage(), it will also move the image in memory in case of KASLR, mirrored memory or if the image must execute from a certain a priori defined address. There are only two EFI spec compliant ways to load code into memory and execute it: - use LoadImage() and StartImage(), - call ExitBootServices() and take ownership of the entire system, after which anything goes. Given that the EFI zboot decompressor always invokes the EFI stub, and given that both are built from the same set of objects, let's merge the two, so that we can avoid LoadImage()/StartImage but still load our image into memory without breaking the above rules. This also means we can decompress the image directly into its final location, which could be randomized or meet other platform specific constraints that LoadImage() does not know how to adhere to. It also means that, even if the encapsulated image still has the EFI stub incorporated as well, it does not need to be signed for secure boot when wrapping it in the EFI zboot decompressor. In the future, we might decide to retire the EFI stub attached to the decompressed image, but for the time being, they can happily coexist. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi/loongarch: libstub: Split off kernel image relocation for builtin stubArd Biesheuvel3-67/+82
The LoongArch build of the EFI stub is part of the core kernel image, and therefore accesses section markers directly when it needs to figure out the size of the various section. The zboot decompressor does not have access to those symbols, but doesn't really need that either. So let's move handle_kernel_image() into a separate file (or rather, move everything else into a separate file) so that the zboot build does not pull in unused code that links to symbols that it does not define. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi/loongarch: Don't jump to kernel entry via the old imageArd Biesheuvel1-9/+24
Currently, the EFI entry code for LoongArch is set up to copy the executable image to the preferred offset, but instead of branching directly into that image, it branches to the local copy of kernel_entry, and relies on the logic in that function to switch to the link time address instead. This is a bit sloppy, and not something we can support once we merge the EFI decompressor with the EFI stub. So let's clean this up a bit, by adding a helper that computes the offset of kernel_entry from the start of the image, and simply adding the result to VMLINUX_LOAD_ADDRESS. And considering that we cannot execute from anywhere else anyway, let's avoid efi_relocate_kernel() and just allocate the pages instead. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi/arm64: libstub: Split off kernel image relocation for builtin stubArd Biesheuvel5-29/+76
The arm64 build of the EFI stub is part of the core kernel image, and therefore accesses section markers directly when it needs to figure out the size of the various section. The zboot decompressor does not have access to those symbols, but doesn't really need that either. So let's move handle_kernel_image() into a separate file (or rather, move everything else into a separate file) so that the zboot build does not pull in unused code that links to symbols that it does not define. While at it, introduce a helper routine that the generic zboot loader will need to invoke after decompressing the image but before invoking it, to ensure that the I-side view of memory is consistent. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi/riscv: libstub: Split off kernel image relocation for builtin stubArd Biesheuvel3-75/+106
The RISC-V build of the EFI stub is part of the core kernel image, and therefore accesses section markers directly when it needs to figure out the size of the various section. The zboot decompressor does not have access to those symbols, but doesn't really need that either. So let's move handle_kernel_image() into a separate file (or rather, move everything else into a separate file) so that the zboot build does not pull in unused code that links to symbols that it does not define. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Factor out min alignment and preferred kernel load addressArd Biesheuvel3-23/+6
Factor out the expressions that describe the preferred placement of the loaded image as well as the minimum alignment so we can reuse them in the decompressor. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Add image code and data size to the zimage metadataArd Biesheuvel2-13/+11
In order to be able to switch from LoadImage() [which treats the supplied PE/COFF image as file input only, and reconstructs the memory image based on the section descriptors] to a mode where we allocate the memory directly, and invoke the image in place, we need to now how much memory to allocate beyond the end of the image. So copy this information from the payload's PE/COFF header to the end of the compressed version of the payload, so that the decompressor app can access it before performing the decompression itself. We'll also need to size of the code region once we switch arm64 to jumping to the kernel proper with MMU and caches enabled, so let's capture that information as well. Note that SizeOfCode does not account for the header, so we need SizeOfHeaders as well. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Factor out EFI stub entrypoint into separate fileArd Biesheuvel4-64/+100
In preparation for allowing the EFI zboot decompressor to reuse most of the EFI stub machinery, factor out the actual EFI PE/COFF entrypoint into a separate file. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Provide local implementations of strrchr() and memchr()Ard Biesheuvel2-1/+64
Clone the implementations of strrchr() and memchr() in lib/string.c so we can use them in the standalone zboot decompressor app. These routines are used by the FDT handling code. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Move screen_info handling to common codeArd Biesheuvel7-41/+93
Currently, arm64, RISC-V and LoongArch rely on the fact that struct screen_info can be accessed directly, due to the fact that the EFI stub and the core kernel are part of the same image. This will change after a future patch, so let's ensure that the screen_info handling is able to deal with this, by adopting the arm32 approach of passing it as a configuration table. While at it, switch to ACPI reclaim memory to hold the screen_info data, which is more appropriate for this kind of allocation. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Enable efi_printk() in zboot decompressorArd Biesheuvel5-167/+198
Split the efi_printk() routine into its own source file, and provide local implementations of strlen() and strnlen() so that the standalone zboot app can efi_err and efi_info etc. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Clone memcmp() into the stubArd Biesheuvel2-10/+19
We will no longer be able to call into the kernel image once we merge the decompressor with the EFI stub, so we need our own implementation of memcmp(). Let's add the one from lib/string.c and simplify it. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Use local strncmp() implementation unconditionallyArd Biesheuvel1-2/+0
In preparation for moving the EFI stub functionality into the zboot decompressor, switch to the stub's implementation of strncmp() unconditionally. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09arm64: efi: Move efi-entry.S into the libstub source directoryArd Biesheuvel2-2/+59
We will be sharing efi-entry.S with the zboot decompressor build, which does not link against vmlinux directly. So move it into the libstub source directory so we can include in the libstub static library. Signed-off-by: Ard Biesheuvel <[email protected]> Acked-by: Catalin Marinas <[email protected]>
2022-11-09arm64: efi: Move dcache cleaning of loaded image out of efi_enter_kernel()Ard Biesheuvel1-1/+9
The efi_enter_kernel() routine will be shared between the existing EFI stub and the zboot decompressor, and the version of dcache_clean_to_poc() that the core kernel exports to the stub will not be available in the latter case. So move the handling into the .c file which will remain part of the stub build that integrates directly with the kernel proper. Signed-off-by: Ard Biesheuvel <[email protected]> Acked-by: Catalin Marinas <[email protected]>
2022-11-09efi: libstub: Deduplicate ftrace command line argument filteringArd Biesheuvel1-9/+10
No need for the same pattern to be used four times for each architecture individually if we can just apply it once later. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Drop handling of EFI properties tableArd Biesheuvel1-13/+0
The EFI properties table was a short lived experiment that never saw the light of day on non-x86 (if at all) so let's drop the handling of it. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-09efi: libstub: Drop randomization of runtime memory mapArd Biesheuvel1-29/+0
Randomizing the UEFI runtime memory map requires the use of the SetVirtualAddressMap() EFI boot service, which we prefer to avoid. So let's drop randomization, which was already problematic in combination with hibernation, which means that distro kernels never enabled it in the first place. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-11-07ARM: 9255/1: efi/dump UEFI runtime page tables for ARMWang Kefeng1-2/+2
UEFI runtime page tables dump only for ARM64 at present, but ARM support EFI and ARM_PTDUMP_DEBUGFS now. Since ARM could potentially execute with a 1G/3G user/kernel split, choosing 1G as the upper limit for UEFI runtime end, with this, we could enable UEFI runtime page tables on ARM. Acked-by: Ard Biesheuvel <[email protected]> Tested-by: Ard Biesheuvel <[email protected]> Signed-off-by: Kefeng Wang <[email protected]> Signed-off-by: Russell King (Oracle) <[email protected]>
2022-10-28efi: efivars: Fix variable writes with unsupported query_variable_store()Ard Biesheuvel1-48/+20
Commit 8a254d90a775 ("efi: efivars: Fix variable writes without query_variable_store()") addressed an issue that was introduced during the EFI variable store refactor, where alternative implementations of the efivars layer that lacked query_variable_store() would no longer work. Unfortunately, there is another case to consider here, which was missed: if the efivars layer is backed by the EFI runtime services as usual, but the EFI implementation predates the introduction of QueryVariableInfo(), we will return EFI_UNSUPPORTED, and this is no longer being dealt with correctly. So let's fix this, and while at it, clean up the code a bit, by merging the check_var_size() routines as well as their callers. Cc: <[email protected]> # v6.0 Fixes: bbc6d2c6ef22 ("efi: vars: Switch to new wrapper layer") Signed-off-by: Ard Biesheuvel <[email protected]> Tested-by: Aditya Garg <[email protected]>
2022-10-24efi: random: Use 'ACPI reclaim' memory for random seedArd Biesheuvel1-1/+6
EFI runtime services data is guaranteed to be preserved by the OS, making it a suitable candidate for the EFI random seed table, which may be passed to kexec kernels as well (after refreshing the seed), and so we need to ensure that the memory is preserved without support from the OS itself. However, runtime services data is intended for allocations that are relevant to the implementations of the runtime services themselves, and so they are unmapped from the kernel linear map, and mapped into the EFI page tables that are active while runtime service invocations are in progress. None of this is needed for the RNG seed. So let's switch to EFI 'ACPI reclaim' memory: in spite of the name, there is nothing exclusively ACPI about it, it is simply a type of allocation that carries firmware provided data which may or may not be relevant to the OS, and it is left up to the OS to decide whether to reclaim it after having consumed its contents. Given that in Linux, we never reclaim these allocations, it is a good choice for the EFI RNG seed, as the allocation is guaranteed to survive kexec reboots. One additional reason for changing this now is to align it with the upcoming recommendation for EFI bootloader provided RNG seeds, which must not use EFI runtime services code/data allocations. Cc: <[email protected]> # v4.14+ Signed-off-by: Ard Biesheuvel <[email protected]> Reviewed-by: Ilias Apalodimas <[email protected]>
2022-10-24efi: random: reduce seed size to 32 bytesArd Biesheuvel1-1/+1
We no longer need at least 64 bytes of random seed to permit the early crng init to complete. The RNG is now based on Blake2s, so reduce the EFI seed size to the Blake2s hash size, which is sufficient for our purposes. While at it, drop the READ_ONCE(), which was supposed to prevent size from being evaluated after seed was unmapped. However, this cannot actually happen, so READ_ONCE() is unnecessary here. Cc: <[email protected]> # v4.14+ Signed-off-by: Ard Biesheuvel <[email protected]> Reviewed-by: Jason A. Donenfeld <[email protected]> Acked-by: Ilias Apalodimas <[email protected]>
2022-10-24efi/tpm: Pass correct address to memblock_reserveJerry Snitselaar1-1/+1
memblock_reserve() expects a physical address, but the address being passed for the TPM final events log is what was returned from early_memremap(). This results in something like the following: [ 0.000000] memblock_reserve: [0xffffffffff2c0000-0xffffffffff2c00e4] efi_tpm_eventlog_init+0x324/0x370 Pass the address from efi like what is done for the TPM events log. Fixes: c46f3405692d ("tpm: Reserve the TPM final events table") Cc: Matthew Garrett <[email protected]> Cc: Jarkko Sakkinen <[email protected]> Cc: Bartosz Szczepanek <[email protected]> Cc: Ard Biesheuvel <[email protected]> Signed-off-by: Jerry Snitselaar <[email protected]> Acked-by: Jarkko Sakkinen <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-21efi: runtime: Don't assume virtual mappings are missing if VA == PA == 0Ard Biesheuvel3-6/+6
The generic EFI stub can be instructed to avoid SetVirtualAddressMap(), and simply run with the firmware's 1:1 mapping. In this case, it populates the virtual address fields of the runtime regions in the memory map with the physical address of each region, so that the mapping code has to be none the wiser. Only if SetVirtualAddressMap() fails, the virtual addresses are wiped and the kernel code knows that the regions cannot be mapped. However, wiping amounts to setting it to zero, and if a runtime region happens to live at physical address 0, its valid 1:1 mapped virtual address could be mistaken for a wiped field, resulting on loss of access to the EFI services at runtime. So let's only assume that VA == 0 means 'no runtime services' if the region in question does not live at PA 0x0. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-21efi: libstub: Fix incorrect payload size in zboot headerArd Biesheuvel1-1/+2
The linker script symbol definition that captures the size of the compressed payload inside the zboot decompressor (which is exposed via the image header) refers to '.' for the end of the region, which does not give the correct result as the expression is not placed at the end of the payload. So use the symbol name explicitly. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-21efi: libstub: Give efi_main() asmlinkage qualificationArd Biesheuvel1-3/+3
To stop the bots from sending sparse warnings to me and the list about efi_main() not having a prototype, decorate it with asmlinkage so that it is clear that it is called from assembly, and therefore needs to remain external, even if it is never declared in a header file. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-21efi: efivars: Fix variable writes without query_variable_store()Ard Biesheuvel1-5/+5
Commit bbc6d2c6ef22 ("efi: vars: Switch to new wrapper layer") refactored the efivars layer so that the 'business logic' related to which UEFI variables affect the boot flow in which way could be moved out of it, and into the efivarfs driver. This inadvertently broke setting variables on firmware implementations that lack the QueryVariableInfo() boot service, because we no longer tolerate a EFI_UNSUPPORTED result from check_var_size() when calling efivar_entry_set_get_size(), which now ends up calling check_var_size() a second time inadvertently. If QueryVariableInfo() is missing, we support writes of up to 64k - let's move that logic into check_var_size(), and drop the redundant call. Cc: <[email protected]> # v6.0 Fixes: bbc6d2c6ef22 ("efi: vars: Switch to new wrapper layer") Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-21efi: ssdt: Don't free memory if ACPI table was loaded successfullyArd Biesheuvel1-0/+2
Amadeusz reports KASAN use-after-free errors introduced by commit 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables"). The problem appears to be that the memory that holds the new ACPI table is now freed unconditionally, instead of only when the ACPI core reported a failure to load the table. So let's fix this, by omitting the kfree() on success. Cc: <[email protected]> # v6.0 Link: https://lore.kernel.org/all/[email protected]/ Fixes: 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables") Reported-by: Amadeusz Sławiński <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-21efi: libstub: Remove zboot signing from build optionsArd Biesheuvel2-47/+4
The zboot decompressor series introduced a feature to sign the PE/COFF kernel image for secure boot as part of the kernel build. This was necessary because there are actually two images that need to be signed: the kernel with the EFI stub attached, and the decompressor application. This is a bit of a burden, because it means that the images must be signed on the the same system that performs the build, and this is not realistic for distros. During the next cycle, we will introduce changes to the zboot code so that the inner image no longer needs to be signed. This means that the outer PE/COFF image can be handled as usual, and be signed later in the release process. Let's remove the associated Kconfig options now so that they don't end up in a LTS release while already being deprecated. Signed-off-by: Ard Biesheuvel <[email protected]>
2022-10-20efi/cper: Export several helpers for ghes_edac to useJia He1-0/+3
Before ghes_edac can be turned back into a proper module again, export several helpers which are going to be used by it. Signed-off-by: Jia He <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Acked-by: Ard Biesheuvel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2022-10-17efi: pstore: Follow convention for the efi-pstore backend nameGuilherme G. Piccoli1-1/+1
For some reason, the efi-pstore backend name (exposed through the pstore infrastructure) is hardcoded as "efi", whereas all the other backends follow a kind of convention in using the module name. Let's do it here as well, to make user's life easier (they might use this info for unloading the module backend, for example). Cc: Ard Biesheuvel <[email protected]> Signed-off-by: Guilherme G. Piccoli <[email protected]> Acked-by: Ard Biesheuvel <[email protected]> Signed-off-by: Kees Cook <[email protected]> Link: https://lore.kernel.org/r/[email protected]