kernel/linux.git/include/asm-generic, branch v3.16.61

Make asm/word-at-a-time.h available on all architectures

2018-10-21T07:46:11+00:00

commit a6e2f029ae34f41adb6ae3812c32c5d326e1abd2 upstream. Added the x86 implementation of word-at-a-time to the generic version, which previously only supported big-endian. Omitted the x86-specific load_unaligned_zeropad(), which in any case is also not present for the existing BE-only implementation of a word-at-a-time, and is only used under CONFIG_DCACHE_WORD_ACCESS. Added as a "generic-y" to the Kbuilds of all architectures that didn't previously have it. Signed-off-by: Chris Metcalf [bwh: Backported to 3.16: - Drop change in arch/nios2 - Adjust context] Signed-off-by: Ben Hutchings

x86/speculation/l1tf: Unbreak !__HAVE_ARCH_PFN_MODIFY_ALLOWED architectures

2018-10-03T03:10:05+00:00

commit 6c26fcd2abfe0a56bbd95271fce02df2896cfd24 upstream. pfn_modify_allowed() and arch_has_pfn_modify_check() are outside of the !__ASSEMBLY__ section in include/asm-generic/pgtable.h, which confuses assembler on archs that don't have __HAVE_ARCH_PFN_MODIFY_ALLOWED (e.g. ia64) and breaks build: include/asm-generic/pgtable.h: Assembler messages: include/asm-generic/pgtable.h:538: Error: Unknown opcode `static inline bool pfn_modify_allowed(unsigned long pfn,pgprot_t prot)' include/asm-generic/pgtable.h:540: Error: Unknown opcode `return true' include/asm-generic/pgtable.h:543: Error: Unknown opcode `static inline bool arch_has_pfn_modify_check(void)' include/asm-generic/pgtable.h:545: Error: Unknown opcode `return false' arch/ia64/kernel/entry.S:69: Error: `mov' does not fit into bundle Move those two static inlines into the !__ASSEMBLY__ section so that they don't confuse the asm build pass. Fixes: 42e4089c7890 ("x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings") Signed-off-by: Jiri Kosina Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman [groeck: Context changes] Signed-off-by: Guenter Roeck Signed-off-by: Ben Hutchings

x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings

2018-10-03T03:10:02+00:00

commit 42e4089c7890725fcd329999252dc489b72f2921 upstream. For L1TF PROT_NONE mappings are protected by inverting the PFN in the page table entry. This sets the high bits in the CPU's address space, thus making sure to point to not point an unmapped entry to valid cached memory. Some server system BIOSes put the MMIO mappings high up in the physical address space. If such an high mapping was mapped to unprivileged users they could attack low memory by setting such a mapping to PROT_NONE. This could happen through a special device driver which is not access protected. Normal /dev/mem is of course access protected. To avoid this forbid PROT_NONE mappings or mprotect for high MMIO mappings. Valid page mappings are allowed because the system is then unsafe anyways. It's not expected that users commonly use PROT_NONE on MMIO. But to minimize any impact this is only enforced if the mapping actually refers to a high MMIO address (defined as the MAX_PA-1 bit being set), and also skip the check for root. For mmaps this is straight forward and can be handled in vm_insert_pfn and in remap_pfn_range(). For mprotect it's a bit trickier. At the point where the actual PTEs are accessed a lot of state has been changed and it would be difficult to undo on an error. Since this is a uncommon case use a separate early page talk walk pass for MMIO PROT_NONE mappings that checks for this condition early. For non MMIO and non PROT_NONE there are no changes. [dwmw2: Backport to 4.9] [groeck: Backport to 4.4] Signed-off-by: Andi Kleen Signed-off-by: Thomas Gleixner Reviewed-by: Josh Poimboeuf Acked-by: Dave Hansen Signed-off-by: David Woodhouse Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings

asm-generic: drop unused pte_file* helpers

2018-10-03T03:09:52+00:00

commit 5064c8e19dc215afae8ffae95570e7f22062d49c upstream. All users are gone. Signed-off-by: Kirill A. Shutemov Cc: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

scsi: dma-mapping: always provide dma_get_cache_alignment

2018-03-03T15:51:32+00:00

commit 860dd4424f344400b491b212ee4acb3a358ba9d9 upstream. Provide the dummy version of dma_get_cache_alignment that always returns 1 even if CONFIG_HAS_DMA is not set, so that drivers and subsystems can use it without ifdefs. Signed-off-by: Christoph Hellwig Signed-off-by: Martin K. Petersen [bwh: Backported to 3.16: Also delete the conflicting declaration in ] Signed-off-by: Ben Hutchings

KAISER: Kernel Address Isolation

2018-01-09T00:35:13+00:00

This patch introduces our implementation of KAISER (Kernel Address Isolation to have Side-channels Efficiently Removed), a kernel isolation technique to close hardware side channels on kernel address information. More information about the patch can be found on: https://github.com/IAIK/KAISER From: Richard Fellner From: Daniel Gruss Subject: [RFC, PATCH] x86_64: KAISER - do not map kernel in user mode Date: Thu, 4 May 2017 14:26:50 +0200 Link: http://marc.info/?l=linux-kernel&m=149390087310405&w=2 Kaiser-4.10-SHA1: c4b1831d44c6144d3762ccc72f0c4e71a0c713e5 To: To: Cc: Cc: Cc: Michael Schwarz Cc: Richard Fellner Cc: Ingo Molnar Cc: Cc: After several recent works [1,2,3] KASLR on x86_64 was basically considered dead by many researchers. We have been working on an efficient but effective fix for this problem and found that not mapping the kernel space when running in user mode is the solution to this problem [4] (the corresponding paper [5] will be presented at ESSoS17). With this RFC patch we allow anybody to configure their kernel with the flag CONFIG_KAISER to add our defense mechanism. If there are any questions we would love to answer them. We also appreciate any comments! Cheers, Daniel (+ the KAISER team from Graz University of Technology) [1] http://www.ieee-security.org/TC/SP2013/papers/4977a191.pdf [2] https://www.blackhat.com/docs/us-16/materials/us-16-Fogh-Using-Undocumented-CPU-Behaviour-To-See-Into-Kernel-Mode-And-Break-KASLR-In-The-Process.pdf [3] https://www.blackhat.com/docs/us-16/materials/us-16-Jang-Breaking-Kernel-Address-Space-Layout-Randomization-KASLR-With-Intel-TSX.pdf [4] https://github.com/IAIK/KAISER [5] https://gruss.cc/files/kaiser.pdf (cherry picked from Change-Id: I0eb000c33290af01fc4454ca0c701d00f1d30b1d) Conflicts: arch/x86/entry/entry_64.S (not in this tree) arch/x86/kernel/entry_64.S (patched instead of that) arch/x86/entry/entry_64_compat.S (not in this tree) arch/x86/ia32/ia32entry.S (patched instead of that) arch/x86/include/asm/hw_irq.h arch/x86/include/asm/pgtable_types.h arch/x86/include/asm/processor.h arch/x86/kernel/irqinit.c arch/x86/kernel/process.c arch/x86/mm/Makefile arch/x86/mm/pgtable.c init/main.c Signed-off-by: Hugh Dickins [bwh: Folded in the follow-up patches from Hugh: - kaiser: merged update - kaiser: do not set _PAGE_NX on pgd_none - kaiser: stack map PAGE_SIZE at THREAD_SIZE-PAGE_SIZE - kaiser: fix build and FIXME in alloc_ldt_struct() - kaiser: KAISER depends on SMP - kaiser: fix regs to do_nmi() ifndef CONFIG_KAISER - kaiser: fix perf crashes - kaiser: ENOMEM if kaiser_pagetable_walk() NULL - kaiser: tidied up asm/kaiser.h somewhat - kaiser: tidied up kaiser_add/remove_mapping slightly - kaiser: kaiser_remove_mapping() move along the pgd - kaiser: align addition to x86/mm/Makefile - kaiser: cleanups while trying for gold link - kaiser: name that 0x1000 KAISER_SHADOW_PGD_OFFSET - kaiser: delete KAISER_REAL_SWITCH option - kaiser: vmstat show NR_KAISERTABLE as nr_overhead - kaiser: enhanced by kernel and user PCIDs - kaiser: load_new_mm_cr3() let SWITCH_USER_CR3 flush user - kaiser: PCID 0 for kernel and 128 for user - kaiser: x86_cr3_pcid_noflush and x86_cr3_pcid_user - kaiser: paranoid_entry pass cr3 need to paranoid_exit - kaiser: _pgd_alloc() without __GFP_REPEAT to avoid stalls - kaiser: fix unlikely error in alloc_ldt_struct() - kaiser: drop is_atomic arg to kaiser_pagetable_walk() Backported to 3.16: - Add missing #include in arch/x86/mm/kaiser.c - Use variable PEBS buffer size since we have "perf/x86/intel: Use PAGE_SIZE for PEBS buffer size on Core2" - Renumber X86_FEATURE_INVPCID_SINGLE to avoid collision - Adjust context] Signed-off-by: Ben Hutchings

asm/sections: add helpers to check for section data

2017-11-26T13:50:15+00:00

commit 979559362516bb0f5424505c607210ac054e30ae upstream. Add a helper to check if an object (given an address and a size) is part of a section (given beginning and end addresses). For convenience, also provide a helper that performs this check for __init data using the __init_begin and __init_end limits. Signed-off-by: Thierry Reding Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

cpumask: fix spurious cpumask_of_node() on non-NUMA multi-node configs

2017-11-11T13:33:32+00:00

commit b339752d054fb32863418452dff350a1086885b1 upstream. When !NUMA, cpumask_of_node(@node) equals cpu_online_mask regardless of @node. The assumption seems that if !NUMA, there shouldn't be more than one node and thus reporting cpu_online_mask regardless of @node is correct. However, that assumption was broken years ago to support DISCONTIGMEM and whether a system has multiple nodes or not is separately controlled by NEED_MULTIPLE_NODES. This means that, on a system with !NUMA && NEED_MULTIPLE_NODES, cpumask_of_node() will report cpu_online_mask for all possible nodes, indicating that the CPUs are associated with multiple nodes which is an impossible configuration. This bug has been around forever but doesn't look like it has caused any noticeable symptoms. However, it triggers a WARN recently added to workqueue to verify NUMA affinity configuration. Fix it by reporting empty cpumask on non-zero nodes if !NUMA. Signed-off-by: Tejun Heo Reported-and-tested-by: Geert Uytterhoeven Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

asm-generic: make get_user() clear the destination on errors

2016-11-20T01:17:26+00:00

commit 9ad18b75c2f6e4a78ce204e79f37781f8815c0fa upstream. both for access_ok() failures and for faults halfway through Signed-off-by: Al Viro [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings

asm-generic: make copy_from_user() zero the destination properly

2016-11-20T01:17:25+00:00

commit 2545e5da080b4839dd859e3b09343a884f6ab0e3 upstream. ... in all cases, including the failing access_ok() Note that some architectures using asm-generic/uaccess.h have __copy_from_user() not zeroing the tail on failure halfway through. This variant works either way. Signed-off-by: Al Viro Signed-off-by: Ben Hutchings