kernel.git/arch/x86/platform/efi, branch linux-4.14.y

x86/sme: Explicitly map new EFI memmap table as encrypted

2021-12-22T08:17:59Z

commit 1ff2fc02862d52e18fd3daabcfe840ec27e920a8 upstream. Reserving memory using efi_mem_reserve() calls into the x86 efi_arch_mem_reserve() function. This function will insert a new EFI memory descriptor into the EFI memory map representing the area of memory to be reserved and marking it as EFI runtime memory. As part of adding this new entry, a new EFI memory map is allocated and mapped. The mapping is where a problem can occur. This new memory map is mapped using early_memremap() and generally mapped encrypted, unless the new memory for the mapping happens to come from an area of memory that is marked as EFI_BOOT_SERVICES_DATA memory. In this case, the new memory will be mapped unencrypted. However, during replacement of the old memory map, efi_mem_type() is disabled, so the new memory map will now be long-term mapped encrypted (in efi.memmap), resulting in the map containing invalid data and causing the kernel boot to crash. Since it is known that the area will be mapped encrypted going forward, explicitly map the new memory map as encrypted using early_memremap_prot(). Cc: # 4.14.x Fixes: 8f716c9b5feb ("x86/mm: Add support to access boot related data in the clear") Link: https://lore.kernel.org/all/ebf1eb2940405438a09d51d121ec0d02c8755558.1634752931.git.thomas.lendacky@amd.com/ Signed-off-by: Tom Lendacky [ardb: incorporate Kconfig fix by Arnd] Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

efi/x86: Don't panic or BUG() on non-critical error conditions

2020-02-28T15:36:03Z

[ Upstream commit e2d68a955e49d61fd0384f23e92058dc9b79be5e ] The logic in __efi_enter_virtual_mode() does a number of steps in sequence, all of which may fail in one way or the other. In most cases, we simply print an error and disable EFI runtime services support, but in some cases, we BUG() or panic() and bring down the system when encountering conditions that we could easily handle in the same way. While at it, replace a pointless page-to-virt-phys conversion with one that goes straight from struct page to physical. Signed-off-by: Ard Biesheuvel Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arvind Sankar Cc: Matthew Garrett Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-14-ardb@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

efi/x86: Map the entire EFI vendor string before copying it

2020-02-28T15:35:56Z

[ Upstream commit ffc2760bcf2dba0dbef74013ed73eea8310cc52c ] Fix a couple of issues with the way we map and copy the vendor string: - we map only 2 bytes, which usually works since you get at least a page, but if the vendor string happens to cross a page boundary, a crash will result - only call early_memunmap() if early_memremap() succeeded, or we will call it with a NULL address which it doesn't like, - while at it, switch to early_memremap_ro(), and array indexing rather than pointer dereferencing to read the CHAR16 characters. Signed-off-by: Ard Biesheuvel Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arvind Sankar Cc: Matthew Garrett Cc: linux-efi@vger.kernel.org Fixes: 5b83683f32b1 ("x86: EFI runtime service support") Link: https://lkml.kernel.org/r/20200103113953.9571-5-ardb@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

x86/efi: Update e820 with reserved EFI boot services data to fix kexec breakage

2020-01-12T11:11:50Z

[ Upstream commit af164898482817a1d487964b68f3c21bae7a1beb ] Michael Weiser reported that he got this error during a kexec rebooting: esrt: Unsupported ESRT version 2904149718861218184. The ESRT memory stays in EFI boot services data, and it was reserved in kernel via efi_mem_reserve(). The initial purpose of the reservation is to reuse the EFI boot services data across kexec reboot. For example the BGRT image data and some ESRT memory like Michael reported. But although the memory is reserved it is not updated in the X86 E820 table, and kexec_file_load() iterates system RAM in the IO resource list to find places for kernel, initramfs and other stuff. In Michael's case the kexec loaded initramfs overwrote the ESRT memory and then the failure happened. Since kexec_file_load() depends on the E820 table being updated, just fix this by updating the reserved EFI boot services memory as reserved type in E820. Originally any memory descriptors with EFI_MEMORY_RUNTIME attribute are bypassed in the reservation code path because they are assumed as reserved. But the reservation is still needed for multiple kexec reboots, and it is the only possible case we come here thus just drop the code chunk, then everything works without side effects. On my machine the ESRT memory sits in an EFI runtime data range, it does not trigger the problem, but I successfully tested with BGRT instead. both kexec_load() and kexec_file_load() work and kdump works as well. [ mingo: Edited the changelog. ] Reported-by: Michael Weiser Tested-by: Michael Weiser Signed-off-by: Dave Young Cc: Ard Biesheuvel Cc: Borislav Petkov Cc: Eric W. Biederman Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kexec@lists.infradead.org Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191204075233.GA10520@dhcp-128-65.nay.redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

efi/x86: Do not clean dummy variable in kexec path

2019-11-06T11:43:12Z

[ Upstream commit 2ecb7402cfc7f22764e7bbc80790e66eadb20560 ] kexec reboot fails randomly in UEFI based KVM guest. The firmware just resets while calling efi_delete_dummy_variable(); Unfortunately I don't know how to debug the firmware, it is also possible a potential problem on real hardware as well although nobody reproduced it. The intention of the efi_delete_dummy_variable is to trigger garbage collection when entering virtual mode. But SetVirtualAddressMap can only run once for each physical reboot, thus kexec_enter_virtual_mode() is not necessarily a good place to clean a dummy object. Drop the efi_delete_dummy_variable so that kexec reboot can work. Signed-off-by: Dave Young Signed-off-by: Ard Biesheuvel Acked-by: Matthew Garrett Cc: Ben Dooks Cc: Jarkko Sakkinen Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Lyude Paul Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Link: https://lkml.kernel.org/r/20191002165904.8819-8-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

x86/earlyprintk/efi: Fix infinite loop on some screen widths

2018-12-21T13:13:12Z

[ Upstream commit 79c2206d369b87b19ac29cb47601059b6bf5c291 ] An affected screen resolution is 1366 x 768, which width is not divisible by 8, the default font width. On such screens, when longer lines are earlyprintk'ed, overflow-to-next-line can never trigger, due to the left-most x-coordinate of the next character always less than the screen width. Earlyprintk will infinite loop in trying to print the rest of the string but unable to, due to the line being full. This patch makes the trigger consider the right-most x-coordinate, instead of left-most, as the value to compare against the screen width threshold. Signed-off-by: YiFei Zhu Signed-off-by: Ard Biesheuvel Cc: Andy Lutomirski Cc: Arend van Spriel Cc: Bhupesh Sharma Cc: Borislav Petkov Cc: Dave Hansen Cc: Eric Snowberg Cc: Hans de Goede Cc: Joe Perches Cc: Jon Hunter Cc: Julien Thierry Cc: Linus Torvalds Cc: Marc Zyngier Cc: Matt Fleming Cc: Nathan Chancellor Cc: Peter Zijlstra Cc: Sai Praneeth Prakhya Cc: Sedat Dilek Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181129171230.18699-12-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

x86/efi: Fix efi_call_phys_epilog() with CONFIG_X86_5LEVEL=y

2018-07-03T09:25:05Z

commit cfe19577047e74cdac5826adbdc2337d8437f8fb upstream. Open-coded page table entry checks don't work correctly when we fold the page table level at runtime. pgd_present() on 4-level paging machine always returns true, but open-coded version of the check may return false-negative result and we silently skip the rest of the loop body in efi_call_phys_epilog(). Replace open-coded checks with proper helpers. Signed-off-by: Kirill A. Shutemov Acked-by: Ard Biesheuvel Cc: Andrey Ryabinin Cc: Baoquan He Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: stable@vger.kernel.org # v4.12+ Fixes: 94133e46a0f5 ("x86/efi: Correct EFI identity mapping under 'efi=old_map' when KASLR is enabled") Link: http://lkml.kernel.org/r/20180625120852.18300-1-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86/efi: Free efi_pgd with free_pages()

2018-03-28T16:24:46Z

commit 06ace26f4e6fcf747e890a39193be811777a048a upstream. The efi_pgd is allocated as PGD_ALLOCATION_ORDER pages and therefore must also be freed as PGD_ALLOCATION_ORDER pages with free_pages(). Fixes: d9e9a6418065 ("x86/mm/pti: Allocate a separate user PGD") Signed-off-by: Waiman Long Signed-off-by: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: Dave Hansen Cc: Ard Biesheuvel Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1521746333-19593-1-git-send-email-longman@redhat.com Signed-off-by: Greg Kroah-Hartman

kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK

2018-02-22T14:42:23Z

commit 75f296d93bcebcfe375884ddac79e30263a31766 upstream. Convert all allocations that used a NOTRACK flag to stop using it. Link: http://lkml.kernel.org/r/20171007030159.22241-3-alexander.levin@verizon.com Signed-off-by: Sasha Levin Cc: Alexander Potapenko Cc: Eric W. Biederman Cc: Michal Hocko Cc: Pekka Enberg Cc: Steven Rostedt Cc: Tim Hansen Cc: Vegard Nossum Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

x86/pti: Unbreak EFI old_memmap

2018-01-17T08:45:27Z

commit de53c3786a3ce162a1c815d0c04c766c23ec9c0a upstream. EFI_OLD_MEMMAP's efi_call_phys_prolog() calls set_pgd() with swapper PGD that has PAGE_USER set, which makes PTI set NX on it, and therefore EFI can't execute it's code. Fix that by forcefully clearing _PAGE_NX from the PGD (this can't be done by the pgprot API). _PAGE_NX will be automatically reintroduced in efi_call_phys_epilog(), as _set_pgd() will again notice that this is _PAGE_USER, and set _PAGE_NX on it. Tested-by: Dimitri Sivanich Signed-off-by: Jiri Kosina Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Acked-by: Dave Hansen Cc: Andrea Arcangeli Cc: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1801052215460.11852@cbobk.fhfr.pm Signed-off-by: Greg Kroah-Hartman