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2016-05-17Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: - virt_to_page/page_address optimisations - support for NUMA systems described using device-tree - support for hibernate/suspend-to-disk - proper support for maxcpus= command line parameter - detection and graceful handling of AArch64-only CPUs - miscellaneous cleanups and non-critical fixes * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) arm64: do not enforce strict 16 byte alignment to stack pointer arm64: kernel: Fix incorrect brk randomization arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str arm64: secondary_start_kernel: Remove unnecessary barrier arm64: Ensure pmd_present() returns false after pmd_mknotpresent() arm64: Replace hard-coded values in the pmd/pud_bad() macros arm64: Implement pmdp_set_access_flags() for hardware AF/DBM arm64: Fix typo in the pmdp_huge_get_and_clear() definition arm64: mm: remove unnecessary EXPORT_SYMBOL_GPL arm64: always use STRICT_MM_TYPECHECKS arm64: kvm: Fix kvm teardown for systems using the extended idmap arm64: kaslr: increase randomization granularity arm64: kconfig: drop CONFIG_RTC_LIB dependency arm64: make ARCH_SUPPORTS_DEBUG_PAGEALLOC depend on !HIBERNATION arm64: hibernate: Refuse to hibernate if the boot cpu is offline arm64: kernel: Add support for hibernate/suspend-to-disk PM / Hibernate: Call flush_icache_range() on pages restored in-place arm64: Add new asm macro copy_page arm64: Promote KERNEL_START/KERNEL_END definitions to a header file arm64: kernel: Include _AC definition in page.h ...
2016-05-07efi: Merge boolean flag argumentsJulia Lawall
The parameters atomic and duplicates of efivar_init always have opposite values. Drop the parameter atomic, replace the uses of !atomic with duplicates, and update the call sites accordingly. The code using duplicates is slightly reorganized with an 'else', to avoid duplicating the lock code. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Saurabh Sengar <saurabh.truth@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vaishali Thakkar <vaishali.thakkar@oracle.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462570771-13324-5-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07efi/capsule: Move 'capsule' to the stack in efi_capsule_supported()Matt Fleming
Dan Carpenter reports that passing the address of the pointer to the kmalloc()'d memory for 'capsule' is dangerous: "drivers/firmware/efi/capsule.c:109 efi_capsule_supported() warn: did you mean to pass the address of 'capsule' 108 109 status = efi.query_capsule_caps(&capsule, 1, &max_size, reset); ^^^^^^^^ If we modify capsule inside this function call then at the end of the function we aren't freeing the original pointer that we allocated." Ard Biesheuvel noted that we don't even need to call kmalloc() since the object we allocate isn't very big and doesn't need to persist after the function returns. Place 'capsule' on the stack instead. Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kweh Hock Leong <hock.leong.kweh@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: joeyli <jlee@suse.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462570771-13324-4-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07efibc: Fix excessive stack footprint warningJeremy Compostella
GCC complains about a newly added file for the EFI Bootloader Control: drivers/firmware/efi/efibc.c: In function 'efibc_set_variable': drivers/firmware/efi/efibc.c:53:1: error: the frame size of 2272 bytes is larger than 1024 bytes [-Werror=frame-larger-than=] The problem is the declaration of a local variable of type struct efivar_entry, which is by itself larger than the warning limit of 1024 bytes. Use dynamic memory allocation instead of stack memory for the entry object. This patch also fixes a potential buffer overflow. Reported-by: Ingo Molnar <mingo@kernel.org> Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com> [ Updated changelog to include GCC error ] Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462570771-13324-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07efi/capsule: Make efi_capsule_pending() locklessMatt Fleming
Taking a mutex in the reboot path is bogus because we cannot sleep with interrupts disabled, such as when rebooting due to panic(), BUG: sleeping function called from invalid context at kernel/locking/mutex.c:97 in_atomic(): 0, irqs_disabled(): 1, pid: 7, name: rcu_sched Call Trace: dump_stack+0x63/0x89 ___might_sleep+0xd8/0x120 __might_sleep+0x49/0x80 mutex_lock+0x20/0x50 efi_capsule_pending+0x1d/0x60 native_machine_emergency_restart+0x59/0x280 machine_emergency_restart+0x19/0x20 emergency_restart+0x18/0x20 panic+0x1ba/0x217 In this case all other CPUs will have been stopped by the time we execute the platform reboot code, so 'capsule_pending' cannot change under our feet. We wouldn't care even if it could since we cannot wait for it complete. Also, instead of relying on the external 'system_state' variable just use a reboot notifier, so we can set 'stop_capsules' while holding 'capsule_mutex', thereby avoiding a race where system_state is updated while we're in the middle of efi_capsule_update_locked() (since CPUs won't have been stopped at that point). Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kweh Hock Leong <hock.leong.kweh@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: joeyli <jlee@suse.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462570771-13324-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28arm64: kaslr: increase randomization granularityArd Biesheuvel
Currently, our KASLR implementation randomizes the placement of the core kernel at 2 MB granularity. This is based on the arm64 kernel boot protocol, which mandates that the kernel is loaded TEXT_OFFSET bytes above a 2 MB aligned base address. This requirement is a result of the fact that the block size used by the early mapping code may be 2 MB at the most (for a 4 KB granule kernel) But we can do better than that: since a KASLR kernel needs to be relocated in any case, we can tolerate a physical misalignment as long as the virtual misalignment relative to this 2 MB block size is equal in size, and code to deal with this is already in place. Since we align the kernel segments to 64 KB, let's randomize the physical offset at 64 KB granularity as well (unless CONFIG_DEBUG_ALIGN_RODATA is enabled). This way, the page table and TLB footprint is not affected. The higher granularity allows for 5 bits of additional entropy to be used. Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-28efi/runtime-wrappers: Remove ARCH_EFI_IRQ_FLAGS_MASK #ifdefMark Rutland
Now that arm, arm64, and x86 all provide ARCH_EFI_IRQ_FLAGS_MASK, we can get rid of the trivial and now unused implementation of efi_call_virt_check_flags(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-41-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/runtime-wrappers: Detect firmware IRQ flag corruptionMark Rutland
The UEFI spec allows runtime services to be called with interrupts masked or unmasked, and if a runtime service function needs to mask interrupts, it must restore the mask to its original state before returning (i.e. from the PoV of the OS, this does not change across a call). Firmware should never unmask exceptions, as these may then be taken by the OS unexpectedly. Unfortunately, some firmware has been seen to unmask IRQs (and potentially other maskable exceptions) across runtime services calls, leaving IRQ flags corrupted after returning from a runtime services function call. This may be detected by the IRQ tracing code, but often goes unnoticed, leaving a potentially disastrous bug hidden. This patch detects when the IRQ flags are corrupted by an EFI runtime services call, logging the call and specific corruption to the console. While restoring the expected value of the flags is insufficient to avoid problems, we do so to avoid redundant warnings from elsewhere (e.g. IRQ tracing). The set of bits in flags which we want to check is architecture-specific (e.g. we want to check FIQ on arm64, but not the zero flag on x86), so each arch must provide ARCH_EFI_IRQ_FLAGS_MASK to describe those. In the absence of this mask, the check is a no-op, and we redundantly save the flags twice, but that will be short-lived as subsequent patches will implement this and remove the scaffolding. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-37-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/runtime-wrappers: Remove redundant #ifdefsMark Rutland
Now that all users of the EFI runtime wrappers (arm,arm64,x86) have been migrated to the new setup/teardown macros, we don't need to support overridden {__,}efi_call_virt() implementations. This patch removes the unnecessary #ifdefs. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-36-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/runtime-wrappers: Add {__,}efi_call_virt() templatesMark Rutland
Currently each architecture must implement two macros, efi_call_virt() and __efi_call_virt(), which only differ by the presence or absence of a return type. Otherwise, the logic surrounding the call is identical. As each architecture must define the entire body of each, we can't place any generic manipulation (e.g. irq flag validation) in the middle. This patch adds template implementations of these macros. With these, arch code can implement three template macros, avoiding reptition for the void/non-void return cases: * arch_efi_call_virt_setup() Sets up the environment for the call (e.g. switching page tables, allowing kernel-mode use of floating point, if required). * arch_efi_call_virt() Performs the call. The last expression in the macro must be the call itself, allowing the logic to be shared by the void and non-void cases. * arch_efi_call_virt_teardown() Restores the usual kernel environment once the call has returned. While the savings from repition are minimal, we additionally gain the ability to add common code around the call with the call environment set up. This can be used to detect common firmware issues (e.g. bad irq mask management). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-32-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm-init: Reserve rather than unmap the memory map for ARM as wellArd Biesheuvel
Now that ARM has a fully functional memremap() implementation, there is no longer a need to remove the UEFI memory map from the linear mapping in order to be able to create a permanent mapping for it using generic code. So remove the 'IS_ENABLED(CONFIG_ARM)' conditional we added in: 7cc8cbcf82d1 ("efi/arm64: Don't apply MEMBLOCK_NOMAP to UEFI memory map mapping") ... and revert to using memblock_reserve() for both ARM and arm64. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-31-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Add misc char driver interface to update EFI firmwareKweh, Hock Leong
This patch introduces a kernel module to expose a capsule loader interface (misc char device file note) for users to upload capsule binaries. Example: cat firmware.bin > /dev/efi_capsule_loader Any upload error will be returned while doing "cat" through file operation write() function call. Signed-off-by: Kweh, Hock Leong <hock.leong.kweh@intel.com> [ Update comments and Kconfig text ] Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sam Protsenko <semen.protsenko@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: joeyli <jlee@suse.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-30-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Add 'capsule' update supportMatt Fleming
The EFI capsule mechanism allows data blobs to be passed to the EFI firmware. A common use case is performing firmware updates. This patch just introduces the main infrastructure for interacting with the firmware, and a driver that allows users to upload capsules will come in a later patch. Once a capsule has been passed to the firmware, the next reboot must be performed using the ResetSystem() EFI runtime service, which may involve overriding the reboot type specified by reboot=. This ensures the reset value returned by QueryCapsuleCapabilities() is used to reset the system, which is required for the capsule to be processed. efi_capsule_pending() is provided for this purpose. At the moment we only allow a single capsule blob to be sent to the firmware despite the fact that UpdateCapsule() takes a 'CapsuleCount' parameter. This simplifies the API and shouldn't result in any downside since it is still possible to send multiple capsules by repeatedly calling UpdateCapsule(). Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Kweh Hock Leong <hock.leong.kweh@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: joeyli <jlee@suse.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-28-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Move efi_status_to_err() to drivers/firmware/efi/Matt Fleming
Move efi_status_to_err() to the architecture independent code as it's generally useful in all bits of EFI code where there is a need to convert an efi_status_t to a kernel error value. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Kweh Hock Leong <hock.leong.kweh@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: joeyli <jlee@suse.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-27-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efibc: Add EFI Bootloader Control moduleCompostella, Jeremy
This module installs a reboot callback, such that if reboot() is invoked with a string argument NNN, "NNN" is copied to the "LoaderEntryOneShot" EFI variable, to be read by the bootloader. If the string matches one of the boot labels defined in its configuration, the bootloader will boot once to that label. The "LoaderEntryRebootReason" EFI variable is set with the reboot reason: "reboot", "shutdown". The bootloader reads this reboot reason and takes particular action according to its policy. There are reboot implementations that do "reboot <reason>", such as Android's reboot command and Upstart's reboot replacement, which pass the reason as an argument to the reboot syscall. There is no platform-agnostic way how those could be modified to pass the reason to the bootloader, regardless of platform or bootloader. Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stefan Stanacar <stefan.stanacar@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-26-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm*: Wire up 'struct screen_info' to efi-framebuffer platform deviceArd Biesheuvel
This adds code to the ARM and arm64 EFI init routines to expose a platform device of type 'efi-framebuffer' if 'struct screen_info' has been populated appropriately from the GOP protocol by the stub. Since the framebuffer may potentially be located in system RAM, make sure that the region is reserved and marked MEMBLOCK_NOMAP. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-24-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm*/libstub: Wire up GOP protocol to 'struct screen_info'Ard Biesheuvel
This adds the code to the ARM and arm64 versions of the UEFI stub to populate struct screen_info based on the information received from the firmware via the GOP protocol. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-23-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm/libstub: Make screen_info accessible to the UEFI stubArd Biesheuvel
In order to hand over the framebuffer described by the GOP protocol and discovered by the UEFI stub, make struct screen_info accessible by the stub. This involves allocating a loader data buffer and passing it to the kernel proper via a UEFI Configuration Table, since the UEFI stub executes in the context of the decompressor, and cannot access the kernel's copy of struct screen_info directly. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-22-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/libstub: Move Graphics Output Protocol handling to generic codeArd Biesheuvel
The Graphics Output Protocol code executes in the stub, so create a generic version based on the x86 version in libstub so that we can move other archs to it in subsequent patches. The new source file gop.c is added to the libstub build for all architectures, but only wired up for x86. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-18-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm*: Take the Memory Attributes table into accountArd Biesheuvel
Call into the generic memory attributes table support code at the appropriate times during the init sequence so that the UEFI Runtime Services region are mapped according to the strict permissions it specifies. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-15-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Implement generic support for the Memory Attributes tableArd Biesheuvel
This implements shared support for discovering the presence of the Memory Attributes table, and for parsing and validating its contents. The table is validated against the construction rules in the UEFI spec. Since this is a new table, it makes sense to complain if we encounter a table that does not follow those rules. The parsing and validation routine takes a callback that can be specified per architecture, that gets passed each unique validated region, with the virtual address retrieved from the ordinary memory map. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [ Trim pr_*() strings to 80 cols and use EFI consistently. ] Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-14-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Add support for the EFI_MEMORY_ATTRIBUTES_TABLE config tableArd Biesheuvel
This declares the GUID and struct typedef for the new memory attributes table which contains the permissions that can be used to apply stricter permissions to UEFI Runtime Services memory regions. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-13-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm*: Use memremap() to create the persistent memmap mappingArd Biesheuvel
Instead of using ioremap_cache(), which is slightly inappropriate for mapping firmware tables, and is not even allowed on ARM for mapping regions that are covered by a struct page, use memremap(), which was invented for this purpose, and will also reuse the existing kernel direct mapping if the requested region is covered by it. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-10-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Check EFI_MEMORY_DESCRIPTOR version explicitlyArd Biesheuvel
Our efi_memory_desc_t type is based on EFI_MEMORY_DESCRIPTOR version 1 in the UEFI spec. No version updates are expected, but since we are about to introduce support for new firmware tables that use the same descriptor type, it makes sense to at least warn if we encounter other versions. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-9-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Remove global 'memmap' EFI memory mapMatt Fleming
Abolish the poorly named EFI memory map, 'memmap'. It is shadowed by a bunch of local definitions in various files and having two ways to access the EFI memory map ('efi.memmap' vs. 'memmap') is rather confusing. Furthermore, IA64 doesn't even provide this global object, which has caused issues when trying to write generic EFI memmap code. Replace all occurrences with efi.memmap, and convert the remaining iterator code to use for_each_efi_mem_desc(). Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Luck, Tony <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-8-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Iterate over efi.memmap in for_each_efi_memory_desc()Matt Fleming
Most of the users of for_each_efi_memory_desc() are equally happy iterating over the EFI memory map in efi.memmap instead of 'memmap', since the former is usually a pointer to the latter. For those users that want to specify an EFI memory map other than efi.memmap, that can be done using for_each_efi_memory_desc_in_map(). One such example is in the libstub code where the firmware is queried directly for the memory map, it gets iterated over, and then freed. This change goes part of the way toward deleting the global 'memmap' variable, which is not universally available on all architectures (notably IA64) and is rather poorly named. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-7-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm64: Check SetupMode when determining Secure Boot statusLinn Crosetto
According to the UEFI specification (version 2.5 Errata A, page 87): The platform firmware is operating in secure boot mode if the value of the SetupMode variable is 0 and the SecureBoot variable is set to 1. A platform cannot operate in secure boot mode if the SetupMode variable is set to 1. Check the value of the SetupMode variable when determining the state of Secure Boot. Plus also do minor cleanup, change sizeof() use to match kernel style guidelines. Signed-off-by: Linn Crosetto <linn@hpe.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roy Franz <roy.franz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-6-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm64: Report unexpected errors when determining Secure Boot statusLinn Crosetto
Certain code in the boot path may require the ability to determine whether UEFI Secure Boot is definitely enabled, for example printing status to the console. Other code may need to know when UEFI Secure Boot is definitely disabled, for example restricting use of kernel parameters. If an unexpected error is returned from GetVariable() when querying the status of UEFI Secure Boot, return an error to the caller. This allows the caller to determine the definite state, and to take appropriate action if an expected error is returned. Signed-off-by: Linn Crosetto <linn@hpe.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roy Franz <roy.franz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-5-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi/arm*: Drop writable mapping of the UEFI System tableArd Biesheuvel
Commit: 2eec5dedf770 ("efi/arm-init: Use read-only early mappings") updated the early ARM UEFI init code to create the temporary, early mapping of the UEFI System table using read-only attributes, as a hardening measure against inadvertent modification. However, this still leaves the permanent, writable mapping of the UEFI System table, which is only ever referenced during invocations of UEFI Runtime Services, at which time the UEFI virtual mapping is available, which also covers the system table. (This is guaranteed by the fact that SetVirtualAddressMap(), which is a runtime service itself, converts various entries in the table to their virtual equivalents, which implies that the table must be covered by a RuntimeServicesData region that has the EFI_MEMORY_RUNTIME attribute.) So instead of creating this permanent mapping, record the virtual address of the system table inside the UEFI virtual mapping, and dereference that when accessing the table. This protects the contents of the system table from inadvertent (or deliberate) modification when no UEFI Runtime Services calls are in progress. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Get rid of the EFI_SYSTEM_TABLES status bitArd Biesheuvel
The EFI_SYSTEM_TABLES status bit is set by all EFI supporting architectures upon discovery of the EFI system table, but the bit is never tested in any code we have in the tree. So remove it. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Luck, Tony <tony.luck@intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-22efi: Fix out-of-bounds read in variable_matches()Laszlo Ersek
The variable_matches() function can currently read "var_name[len]", for example when: - var_name[0] == 'a', - len == 1 - match_name points to the NUL-terminated string "ab". This function is supposed to accept "var_name" inputs that are not NUL-terminated (hence the "len" parameter"). Document the function, and access "var_name[*match]" only if "*match" is smaller than "len". Reported-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Laszlo Ersek <lersek@redhat.com> Cc: Peter Jones <pjones@redhat.com> Cc: Matthew Garrett <mjg59@coreos.com> Cc: Jason Andryuk <jandryuk@gmail.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.10+ Link: http://thread.gmane.org/gmane.comp.freedesktop.xorg.drivers.intel/86906 Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-04-19efi: ARM: avoid warning about phys_addr_t castArnd Bergmann
memblock_remove() takes a phys_addr_t, which may be narrower than 64 bits, causing a harmless warning: drivers/firmware/efi/arm-init.c: In function 'reserve_regions': include/linux/kernel.h:29:20: error: large integer implicitly truncated to unsigned type [-Werror=overflow] #define ULLONG_MAX (~0ULL) ^ drivers/firmware/efi/arm-init.c:152:21: note: in expansion of macro 'ULLONG_MAX' memblock_remove(0, ULLONG_MAX); This adds an explicit typecast to avoid the warning Fixes: 500899c2cc3e ("efi: ARM/arm64: ignore DT memory nodes instead of removing them") Acked-by Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-15efi: ARM/arm64: ignore DT memory nodes instead of removing themArd Biesheuvel
There are two problems with the UEFI stub DT memory node removal routine: - it deletes nodes as it traverses the tree, which happens to work but is not supported, as deletion invalidates the node iterator; - deleting memory nodes entirely may discard annotations in the form of additional properties on the nodes. Since the discovery of DT memory nodes occurs strictly before the UEFI init sequence, we can simply clear the memblock memory table before parsing the UEFI memory map. This way, it is no longer necessary to remove the nodes, so we can remove that logic from the stub as well. Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-31efi/arm64: Don't apply MEMBLOCK_NOMAP to UEFI memory map mappingArd Biesheuvel
Commit 4dffbfc48d65 ("arm64/efi: mark UEFI reserved regions as MEMBLOCK_NOMAP") updated the mapping logic of both the RuntimeServices regions as well as the kernel's copy of the UEFI memory map to set the MEMBLOCK_NOMAP flag, which causes these regions to be omitted from the kernel direct mapping, and from being covered by a struct page. For the RuntimeServices regions, this is an obvious win, since the contents of these regions have significance to the firmware executable code itself, and are mapped in the EFI page tables using attributes that are described in the UEFI memory map, and which may differ from the attributes we use for mapping system RAM. It also prevents the contents from being modified inadvertently, since the EFI page tables are only live during runtime service invocations. None of these concerns apply to the allocation that covers the UEFI memory map, since it is entirely owned by the kernel. Setting the MEMBLOCK_NOMAP on the region did allow us to use ioremap_cache() to map it both on arm64 and on ARM, since the latter does not allow ioremap_cache() to be used on regions that are covered by a struct page. The ioremap_cache() on ARM restriction will be lifted in the v4.7 timeframe, but in the mean time, it has been reported that commit 4dffbfc48d65 causes a regression on 64k granule kernels. This is due to the fact that, given the 64 KB page size, the region that we end up removing from the kernel direct mapping is rounded up to 64 KB, and this 64 KB page frame may be shared with the initrd when booting via GRUB (which does not align its EFI_LOADER_DATA allocations to 64 KB like the stub does). This will crash the kernel as soon as it tries to access the initrd. Since the issue is specific to arm64, revert back to memblock_reserve()'ing the UEFI memory map when running on arm64. This is a temporary fix for v4.5 and v4.6, and will be superseded in the v4.7 timeframe when we will be able to move back to memblock_reserve() unconditionally. Fixes: 4dffbfc48d65 ("arm64/efi: mark UEFI reserved regions as MEMBLOCK_NOMAP") Reported-by: Mark Salter <msalter@redhat.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Jeremy Linton <jeremy.linton@arm.com> Cc: Mark Langsdorf <mlangsdo@redhat.com> Cc: <stable@vger.kernel.org> # v4.5 Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-03-22kernel: add kcov code coverageDmitry Vyukov
kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system. A notable user-space example is AFL (http://lcamtuf.coredump.cx/afl/). However, this technique is not widely used for kernel testing due to missing compiler and kernel support. kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disbled (e.g. scheduler, locking). Currently there is a single coverage collection mode (tracing), but the API anticipates additional collection modes. Initially I also implemented a second mode which exposes coverage in a fixed-size hash table of counters (what Quentin used in his original patch). I've dropped the second mode for simplicity. This patch adds the necessary support on kernel side. The complimentary compiler support was added in gcc revision 231296. We've used this support to build syzkaller system call fuzzer, which has found 90 kernel bugs in just 2 months: https://github.com/google/syzkaller/wiki/Found-Bugs We've also found 30+ bugs in our internal systems with syzkaller. Another (yet unexplored) direction where kcov coverage would greatly help is more traditional "blob mutation". For example, mounting a random blob as a filesystem, or receiving a random blob over wire. Why not gcov. Typical fuzzing loop looks as follows: (1) reset coverage, (2) execute a bit of code, (3) collect coverage, repeat. A typical coverage can be just a dozen of basic blocks (e.g. an invalid input). In such context gcov becomes prohibitively expensive as reset/collect coverage steps depend on total number of basic blocks/edges in program (in case of kernel it is about 2M). Cost of kcov depends only on number of executed basic blocks/edges. On top of that, kernel requires per-thread coverage because there are always background threads and unrelated processes that also produce coverage. With inlined gcov instrumentation per-thread coverage is not possible. kcov exposes kernel PCs and control flow to user-space which is insecure. But debugfs should not be mapped as user accessible. Based on a patch by Quentin Casasnovas. [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode'] [akpm@linux-foundation.org: unbreak allmodconfig] [akpm@linux-foundation.org: follow x86 Makefile layout standards] Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Tavis Ormandy <taviso@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Kees Cook <keescook@google.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: David Drysdale <drysdale@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22drivers/firmware/efi/efivars.c: use in_compat_syscall() to check for compat ↵Andy Lutomirski
callers This should make no difference on any architecture, as x86's historical is_compat_task behavior really did check whether the calling syscall was a compat syscall. x86's is_compat_task is going away, though. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-21Merge branch 'efi-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Ingo Molnar: "The main changes are: - Use separate EFI page tables when executing EFI firmware code. This isolates the EFI context from the rest of the kernel, which has security and general robustness advantages. (Matt Fleming) - Run regular UEFI firmware with interrupts enabled. This is already the status quo under other OSs. (Ard Biesheuvel) - Various x86 EFI enhancements, such as the use of non-executable attributes for EFI memory mappings. (Sai Praneeth Prakhya) - Various arm64 UEFI enhancements. (Ard Biesheuvel) - ... various fixes and cleanups. The separate EFI page tables feature got delayed twice already, because it's an intrusive change and we didn't feel confident about it - third time's the charm we hope!" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) x86/mm/pat: Fix boot crash when 1GB pages are not supported by the CPU x86/efi: Only map kernel text for EFI mixed mode x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd() efi/arm*: Perform hardware compatibility check efi/arm64: Check for h/w support before booting a >4 KB granular kernel efi/arm: Check for LPAE support before booting a LPAE kernel efi/arm-init: Use read-only early mappings efi/efistub: Prevent __init annotations from being used arm64/vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections efi/arm64: Drop __init annotation from handle_kernel_image() x86/mm/pat: Use _PAGE_GLOBAL bit for EFI page table mappings efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled efi: Reformat GUID tables to follow the format in UEFI spec efi: Add Persistent Memory type name efi: Add NV memory attribute x86/efi: Show actual ending addresses in efi_print_memmap x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0 efivars: Use to_efivar_entry efi: Runtime-wrapper: Get rid of the rtc_lock spinlock ...
2016-03-21Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull 'objtool' stack frame validation from Ingo Molnar: "This tree adds a new kernel build-time object file validation feature (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation. It was written by and is maintained by Josh Poimboeuf. The motivation: there's a category of hard to find kernel bugs, most of them in assembly code (but also occasionally in C code), that degrades the quality of kernel stack dumps/backtraces. These bugs are hard to detect at the source code level. Such bugs result in incorrect/incomplete backtraces most of time - but can also in some rare cases result in crashes or other undefined behavior. The build time correctness checking is done via the new 'objtool' user-space utility that was written for this purpose and which is hosted in the kernel repository in tools/objtool/. The tool's (very simple) UI and source code design is shaped after Git and perf and shares quite a bit of infrastructure with tools/perf (which tooling infrastructure sharing effort got merged via perf and is already upstream). Objtool follows the well-known kernel coding style. Objtool does not try to check .c or .S files, it instead analyzes the resulting .o generated machine code from first principles: it decodes the instruction stream and interprets it. (Right now objtool supports the x86-64 architecture.) From tools/objtool/Documentation/stack-validation.txt: "The kernel CONFIG_STACK_VALIDATION option enables a host tool named objtool which runs at compile time. It has a "check" subcommand which analyzes every .o file and ensures the validity of its stack metadata. It enforces a set of rules on asm code and C inline assembly code so that stack traces can be reliable. Currently it only checks frame pointer usage, but there are plans to add CFI validation for C files and CFI generation for asm files. For each function, it recursively follows all possible code paths and validates the correct frame pointer state at each instruction. It also follows code paths involving special sections, like .altinstructions, __jump_table, and __ex_table, which can add alternative execution paths to a given instruction (or set of instructions). Similarly, it knows how to follow switch statements, for which gcc sometimes uses jump tables." When this new kernel option is enabled (it's disabled by default), the tool, if it finds any suspicious assembly code pattern, outputs warnings in compiler warning format: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup warning: objtool:__schedule()+0x3c0: duplicate frame pointer save warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer ... so that scripts that pick up compiler warnings will notice them. All known warnings triggered by the tool are fixed by the tree, most of the commits in fact prepare the kernel to be warning-free. Most of them are bugfixes or cleanups that stand on their own, but there are also some annotations of 'special' stack frames for justified cases such entries to JIT-ed code (BPF) or really special boot time code. There are two other long-term motivations behind this tool as well: - To improve the quality and reliability of kernel stack frames, so that they can be used for optimized live patching. - To create independent infrastructure to check the correctness of CFI stack frames at build time. CFI debuginfo is notoriously unreliable and we cannot use it in the kernel as-is without extra checking done both on the kernel side and on the build side. The quality of kernel stack frames matters to debuggability as well, so IMO we can merge this without having to consider the live patching or CFI debuginfo angle" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) objtool: Only print one warning per function objtool: Add several performance improvements tools: Copy hashtable.h into tools directory objtool: Fix false positive warnings for functions with multiple switch statements objtool: Rename some variables and functions objtool: Remove superflous INIT_LIST_HEAD objtool: Add helper macros for traversing instructions objtool: Fix false positive warnings related to sibling calls objtool: Compile with debugging symbols objtool: Detect infinite recursion objtool: Prevent infinite recursion in noreturn detection objtool: Detect and warn if libelf is missing and don't break the build tools: Support relative directory path for 'O=' objtool: Support CROSS_COMPILE x86/asm/decoder: Use explicitly signed chars objtool: Enable stack metadata validation on 64-bit x86 objtool: Add CONFIG_STACK_VALIDATION option objtool: Add tool to perform compile-time stack metadata validation x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard sched: Always inline context_switch() ...
2016-03-18Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Here are the main arm64 updates for 4.6. There are some relatively intrusive changes to support KASLR, the reworking of the kernel virtual memory layout and initial page table creation. Summary: - Initial page table creation reworked to avoid breaking large block mappings (huge pages) into smaller ones. The ARM architecture requires break-before-make in such cases to avoid TLB conflicts but that's not always possible on live page tables - Kernel virtual memory layout: the kernel image is no longer linked to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of the vmalloc space, allowing the kernel to be loaded (nearly) anywhere in physical RAM - Kernel ASLR: position independent kernel Image and modules being randomly mapped in the vmalloc space with the randomness is provided by UEFI (efi_get_random_bytes() patches merged via the arm64 tree, acked by Matt Fleming) - Implement relative exception tables for arm64, required by KASLR (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but actual x86 conversion to deferred to 4.7 because of the merge dependencies) - Support for the User Access Override feature of ARMv8.2: this allows uaccess functions (get_user etc.) to be implemented using LDTR/STTR instructions. Such instructions, when run by the kernel, perform unprivileged accesses adding an extra level of protection. The set_fs() macro is used to "upgrade" such instruction to privileged accesses via the UAO bit - Half-precision floating point support (part of ARMv8.2) - Optimisations for CPUs with or without a hardware prefetcher (using run-time code patching) - copy_page performance improvement to deal with 128 bytes at a time - Sanity checks on the CPU capabilities (via CPUID) to prevent incompatible secondary CPUs from being brought up (e.g. weird big.LITTLE configurations) - valid_user_regs() reworked for better sanity check of the sigcontext information (restored pstate information) - ACPI parking protocol implementation - CONFIG_DEBUG_RODATA enabled by default - VDSO code marked as read-only - DEBUG_PAGEALLOC support - ARCH_HAS_UBSAN_SANITIZE_ALL enabled - Erratum workaround Cavium ThunderX SoC - set_pte_at() fix for PROT_NONE mappings - Code clean-ups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits) arm64: kasan: Fix zero shadow mapping overriding kernel image shadow arm64: kasan: Use actual memory node when populating the kernel image shadow arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission arm64: Fix misspellings in comments. arm64: efi: add missing frame pointer assignment arm64: make mrs_s prefixing implicit in read_cpuid arm64: enable CONFIG_DEBUG_RODATA by default arm64: Rework valid_user_regs arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly arm64: KVM: Move kvm_call_hyp back to its original localtion arm64: mm: treat memstart_addr as a signed quantity arm64: mm: list kernel sections in order arm64: lse: deal with clobbered IP registers after branch via PLT arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR arm64: kconfig: add submenu for 8.2 architectural features arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot arm64: Add support for Half precision floating point arm64: Remove fixmap include fragility arm64: Add workaround for Cavium erratum 27456 arm64: mm: Mark .rodata as RO ...
2016-02-29objtool: Mark non-standard object files and directoriesJosh Poimboeuf
Code which runs outside the kernel's normal mode of operation often does unusual things which can cause a static analysis tool like objtool to emit false positive warnings: - boot image - vdso image - relocation - realmode - efi - head - purgatory - modpost Set OBJECT_FILES_NON_STANDARD for their related files and directories, which will tell objtool to skip checking them. It's ok to skip them because they don't affect runtime stack traces. Also skip the following code which does the right thing with respect to frame pointers, but is too "special" to be validated by a tool: - entry - mcount Also skip the test_nx module because it modifies its exception handling table at runtime, which objtool can't understand. Fortunately it's just a test module so it doesn't matter much. Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it might eventually be useful for other tools. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24arm64: efi: invoke EFI_RNG_PROTOCOL to supply KASLR randomnessArd Biesheuvel
Since arm64 does not use a decompressor that supplies an execution environment where it is feasible to some extent to provide a source of randomness, the arm64 KASLR kernel depends on the bootloader to supply some random bits in the /chosen/kaslr-seed DT property upon kernel entry. On UEFI systems, we can use the EFI_RNG_PROTOCOL, if supplied, to obtain some random bits. At the same time, use it to randomize the offset of the kernel Image in physical memory. Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24efi: stub: use high allocation for converted command lineArd Biesheuvel
Before we can move the command line processing before the allocation of the kernel, which is required for detecting the 'nokaslr' option which controls that allocation, move the converted command line higher up in memory, to prevent it from interfering with the kernel itself. Since x86 needs the address to fit in 32 bits, use UINT_MAX as the upper bound there. Otherwise, use ULONG_MAX (i.e., no limit) Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24efi: stub: add implementation of efi_random_alloc()Ard Biesheuvel
This implements efi_random_alloc(), which allocates a chunk of memory of a certain size at a certain alignment, and uses the random_seed argument it receives to randomize the address of the allocation. This is implemented by iterating over the UEFI memory map, counting the number of suitable slots (aligned offsets) within each region, and picking a random number between 0 and 'number of slots - 1' to select the slot, This should guarantee that each possible offset is chosen equally likely. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24efi: stub: implement efi_get_random_bytes() based on EFI_RNG_PROTOCOLArd Biesheuvel
This exposes the firmware's implementation of EFI_RNG_PROTOCOL via a new function efi_get_random_bytes(). Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-22efi/arm*: Perform hardware compatibility checkArd Biesheuvel
Before proceeding with relocating the kernel and parsing the command line, insert a call to check_platform_features() to allow an arch specific check to be performed whether the current kernel can execute on the current hardware. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Jeremy Linton <jeremy.linton@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-11-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22efi/arm64: Check for h/w support before booting a >4 KB granular kernelArd Biesheuvel
A kernel built with support for a page size that is not supported by the hardware it runs on cannot boot to a state where it can inform the user about the failure. If we happen to be booting via UEFI, we can fail gracefully so check if the currently configured page size is supported by the hardware before entering the kernel proper. Note that UEFI mandates support for 4 KB pages, so in that case, no check is needed. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Jeremy Linton <jeremy.linton@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-10-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22efi/arm: Check for LPAE support before booting a LPAE kernelArd Biesheuvel
A kernel built with support for LPAE cannot boot to a state where it can inform the user about if it has to fail due to missing LPAE support in the hardware. If we happen to be booting via UEFI, we can fail gracefully so check for LPAE support in the hardware on CONFIG_ARM_LPAE builds before entering the kernel proper. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Jeremy Linton <jeremy.linton@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-9-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22efi/arm-init: Use read-only early mappingsArd Biesheuvel
The early mappings of the EFI system table contents and the UEFI memory map are read-only from the OS point of view. So map them read-only to protect them from inadvertent modification. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-8-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22efi/efistub: Prevent __init annotations from being usedArd Biesheuvel
__init annotations should not be used in the EFI stub, since the code is either included in the decompressor (x86, ARM) where they have no effect, or the whole stub is __init annotated at the section level (arm64), by renaming the sections. In the second case the __init annotations will be redundant, and will result in section names like .init.init.text, and our linker script does not expect that. So un-#define __init so that its inadvertent use will force a build error. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-7-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22efi/arm64: Drop __init annotation from handle_kernel_image()Ard Biesheuvel
After moving arm64-stub.c to libstub/, all of its sections are emitted as .init.xxx sections automatically, and the __init annotation of handle_kernel_image() causes it to end up in .init.init.text, which is not recognized as an __init section by the linker scripts. So drop the annotation. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-5-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>