user/sven/linux.git/drivers/firmware/efi, branch v4.9.74

efi/esrt: Cleanup bad memory map log messages

2017-12-20T09:07:26Z

[ Upstream commit 822f5845f710e57d7e2df1fd1ee00d6e19d334fe ] The Intel Compute Stick STCK1A8LFC and Weibu F3C platforms both log 2 error messages during boot: efi: requested map not found. esrt: ESRT header is not in the memory map. Searching the web, this seems to affect many other platforms too. Since these messages are logged as errors, they appear on-screen during the boot process even when using the "quiet" boot parameter used by distros. Demote the ESRT error to a warning so that it does not appear on-screen, and delete the error logging from efi_mem_desc_lookup; both callsites of that function log more specific messages upon failure. Out of curiosity I looked closer at the Weibu F3C. There is no entry in the UEFI-provided memory map which corresponds to the ESRT pointer, but hacking the code to map it anyway, the ESRT does appear to be valid with 2 entries. Signed-off-by: Daniel Drake Cc: Matt Fleming Acked-by: Peter Jones Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

efi/esrt: Use memunmap() instead of kfree() to free the remapping

2017-12-14T08:28:11Z

commit 89c5a2d34bda58319e3075e8e7dd727ea25a435c upstream. The remapping result of memremap() should be freed with memunmap(), not kfree(). Signed-off-by: Pan Bian Signed-off-by: Ard Biesheuvel Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20171206095010.24170-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi: Move some sysfs files to be read-only by root

2017-12-14T08:28:11Z

commit af97a77bc01ce49a466f9d4c0125479e2e2230b6 upstream. Thanks to the scripts/leaking_addresses.pl script, it was found that some EFI values should not be readable by non-root users. So make them root-only, and to do that, add a __ATTR_RO_MODE() macro to make this easier, and use it in other places at the same time. Reported-by: Linus Torvalds Tested-by: Dave Young Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ard Biesheuvel Cc: H. Peter Anvin Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20171206095010.24170-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/libstub: Skip GOP with PIXEL_BLT_ONLY format

2017-04-21T07:31:20Z

commit 540f4c0e894f7e46a66dfa424b16424cbdc12c38 upstream. The UEFI Specification permits Graphics Output Protocol (GOP) instances without direct framebuffer access. This is indicated in the Mode structure with a PixelFormat enumeration value of PIXEL_BLT_ONLY. Given that the kernel does not know how to drive a Blt() only framebuffer (which is only permitted before ExitBootServices() anyway), we should disregard such framebuffers when looking for a GOP instance that is suitable for use as the boot console. So modify the EFI GOP initialization to not use a PIXEL_BLT_ONLY instance, preventing attempts later in boot to use an invalid screen_info.lfb_base address. Signed-off-by: Eugene Cohen [ Moved the Blt() only check into the loop and clarified that Blt() only GOPs are unusable by the kernel. ] Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: leif.lindholm@linaro.org Cc: linux-efi@vger.kernel.org Cc: lorenzo.pieralisi@arm.com Fixes: 9822504c1fa5 ("efifb: Enable the efi-framebuffer platform driver ...") Link: http://lkml.kernel.org/r/20170404152744.26687-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/arm: Fix boot crash with CONFIG_CPUMASK_OFFSTACK=y

2017-03-18T11:14:29Z

commit d1eb98143c56f24fef125f5bbed49ae0b52fb7d6 upstream. On ARM and arm64, we use a dedicated mm_struct to map the UEFI Runtime Services regions, which allows us to map those regions on demand, and in a way that is guaranteed to be compatible with incoming kernels across kexec. As it turns out, we don't fully initialize the mm_struct in the same way as process mm_structs are initialized on fork(), which results in the following crash on ARM if CONFIG_CPUMASK_OFFSTACK=y is enabled: ... EFI Variables Facility v0.08 2004-May-17 Unable to handle kernel NULL pointer dereference at virtual address 00000000 [...] Process swapper/0 (pid: 1) ... __memzero() check_and_switch_context() virt_efi_get_next_variable() efivar_init() efivars_sysfs_init() do_one_initcall() ... This is due to a missing call to mm_init_cpumask(), so add it. Signed-off-by: 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/1488395154-29786-1-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/fdt: Avoid FDT manipulation after ExitBootServices()

2017-02-09T07:08:25Z

commit c8f325a59cfc718d13a50fbc746ed9b415c25e92 upstream. Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel Tested-by: Riku Voipio Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86/efi: Don't allocate memmap through memblock after mm_init()

2017-01-19T19:18:00Z

commit 20b1e22d01a4b0b11d3a1066e9feb04be38607ec upstream. With the following commit: 4bc9f92e64c8 ("x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data") ... efi_bgrt_init() calls into the memblock allocator through efi_mem_reserve() => efi_arch_mem_reserve() *after* mm_init() has been called. Indeed, KASAN reports a bad read access later on in efi_free_boot_services(): BUG: KASAN: use-after-free in efi_free_boot_services+0xae/0x24c at addr ffff88022de12740 Read of size 4 by task swapper/0/0 page:ffffea0008b78480 count:0 mapcount:-127 mapping: (null) index:0x1 flags: 0x5fff8000000000() [...] Call Trace: dump_stack+0x68/0x9f kasan_report_error+0x4c8/0x500 kasan_report+0x58/0x60 __asan_load4+0x61/0x80 efi_free_boot_services+0xae/0x24c start_kernel+0x527/0x562 x86_64_start_reservations+0x24/0x26 x86_64_start_kernel+0x157/0x17a start_cpu+0x5/0x14 The instruction at the given address is the first read from the memmap's memory, i.e. the read of md->type in efi_free_boot_services(). Note that the writes earlier in efi_arch_mem_reserve() don't splat because they're done through early_memremap()ed addresses. So, after memblock is gone, allocations should be done through the "normal" page allocator. Introduce a helper, efi_memmap_alloc() for this. Use it from efi_arch_mem_reserve(), efi_free_boot_services() and, for the sake of consistency, from efi_fake_memmap() as well. Note that for the latter, the memmap allocations cease to be page aligned. This isn't needed though. Tested-by: Dan Williams Signed-off-by: Nicolai Stange Reviewed-by: Ard Biesheuvel Cc: Dave Young Cc: Linus Torvalds Cc: Matt Fleming Cc: Mika Penttilä Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 4bc9f92e64c8 ("x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data") Link: http://lkml.kernel.org/r/20170105125130.2815-1-nicstange@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/libstub/arm*: Pass latest memory map to the kernel

2017-01-19T19:18:00Z

commit abfb7b686a3e5be27bf81db62f9c5c895b76f5d1 upstream. As reported by James Morse, the current libstub code involving the annotated memory map only works somewhat correctly by accident, due to the fact that a pool allocation happens to be reused immediately, retaining its former contents on most implementations of the UEFI boot services. Instead of juggling memory maps, which makes the code more complex than it needs to be, simply put placeholder values into the FDT for the memory map parameters, and only write the actual values after ExitBootServices() has been called. Reported-by: James Morse Signed-off-by: Ard Biesheuvel Cc: Jeffrey Hugo Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-arm-kernel@lists.infradead.org Cc: linux-efi@vger.kernel.org Fixes: ed9cc156c42f ("efi/libstub: Use efi_exit_boot_services() in FDT") Link: http://lkml.kernel.org/r/1482587963-20183-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/efivar_ssdt_load: Don't return success on allocation failure

2017-01-12T10:39:24Z

commit a75dcb5848359f488c32c0aef8711d9bd37a77b8 upstream. We should return -ENOMEM here, instead of success. Signed-off-by: Dan Carpenter Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 475fb4e8b2f4 ("efi / ACPI: load SSTDs from EFI variables") Link: http://lkml.kernel.org/r/20161018143318.15673-9-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/arm: Fix absolute relocation detection for older toolchains

2016-10-19T12:49:44Z

When building the ARM kernel with CONFIG_EFI=y, the following build error may occur when using a less recent version of binutils (2.23 or older): STUBCPY drivers/firmware/efi/libstub/lib-sort.stub.o 00000000 R_ARM_ABS32 sort 00000004 R_ARM_ABS32 __ksymtab_strings drivers/firmware/efi/libstub/lib-sort.stub.o: absolute symbol references not allowed in the EFI stub (and when building with debug symbols, the list above is much longer, and contains all the internal references between the .debug sections and the actual code) This issue is caused by the fact that objcopy v2.23 or earlier does not support wildcards in its -R and -j options, which means the following line from the Makefile: STUBCOPY_FLAGS-y := -R .debug* -R *ksymtab* -R *kcrctab* fails to take effect, leaving harmless absolute relocations in the binary that are indistinguishable from relocations that may cause crashes at runtime due to the fact that these relocations are resolved at link time using the virtual address of the kernel, which is always different from the address at which the EFI firmware loads and invokes the stub. So, as a workaround, disable debug symbols explicitly when building the stub for ARM, and strip the ksymtab and kcrctab symbols for the only exported symbol we currently reuse in the stub, which is 'sort'. Tested-by: Jon Hunter Signed-off-by: Ard Biesheuvel Reviewed-by: Matt Fleming Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1476805991-7160-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar