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2018-06-04Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: - Centaur CPU updates (David Wang) - AMD and other CPU topology enumeration improvements and fixes (Borislav Petkov, Thomas Gleixner, Suravee Suthikulpanit) - Continued 5-level paging work (Kirill A. Shutemov) * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Mark __pgtable_l5_enabled __initdata x86/mm: Mark p4d_offset() __always_inline x86/mm: Introduce the 'no5lvl' kernel parameter x86/mm: Stop pretending pgtable_l5_enabled is a variable x86/mm: Unify pgtable_l5_enabled usage in early boot code x86/boot/compressed/64: Fix trampoline page table address calculation x86/CPU: Move x86_cpuinfo::x86_max_cores assignment to detect_num_cpu_cores() x86/Centaur: Report correct CPU/cache topology x86/CPU: Move cpu_detect_cache_sizes() into init_intel_cacheinfo() x86/CPU: Make intel_num_cpu_cores() generic x86/CPU: Move cpu local function declarations to local header x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when available x86/CPU: Modify detect_extended_topology() to return result x86/CPU/AMD: Calculate last level cache ID from number of sharing threads x86/CPU: Rename intel_cacheinfo.c to cacheinfo.c perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be present x86/Centaur: Initialize supported CPU features properly
2018-05-19x86/mm: Stop pretending pgtable_l5_enabled is a variableKirill A. Shutemov1-2/+2
pgtable_l5_enabled is defined using cpu_feature_enabled() but we refer to it as a variable. This is misleading. Make pgtable_l5_enabled() a function. We cannot literally define it as a function due to circular dependencies between header files. Function-alike macros is close enough. Signed-off-by: Kirill A. Shutemov <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2018-04-26x86/fault: Dump user opcode bytes on fatal faultsBorislav Petkov1-2/+5
Sometimes it is useful to see which user opcode bytes RIP points to when a fault happens: be it to rule out RIP corruption, to dump info early during boot, when doing core dumps is impossible due to not having a writable filesystem yet. Sometimes it is useful if debugging an issue and one doesn't have access to the executable which caused the fault in order to disassemble it. That last aspect might have some security implications so show_unhandled_signals could be revisited for that or a new config option added. Signed-off-by: Borislav Petkov <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman1-0/+1
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <[email protected]>
2018-04-02Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-41/+19
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: - Extend the memmap= boot parameter syntax to allow the redeclaration and dropping of existing ranges, and to support all e820 range types (Jan H. Schönherr) - Improve the W+X boot time security checks to remove false positive warnings on Xen (Jan Beulich) - Support booting as Xen PVH guest (Juergen Gross) - Improved 5-level paging (LA57) support, in particular it's possible now to have a single kernel image for both 4-level and 5-level hardware (Kirill A. Shutemov) - AMD hardware RAM encryption support (SME/SEV) fixes (Tom Lendacky) - Preparatory commits for hardware-encrypted RAM support on Intel CPUs. (Kirill A. Shutemov) - Improved Intel-MID support (Andy Shevchenko) - Show EFI page tables in page_tables debug files (Andy Lutomirski) - ... plus misc fixes and smaller cleanups * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits) x86/cpu/tme: Fix spelling: "configuation" -> "configuration" x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT x86/mm: Update comment in detect_tme() regarding x86_phys_bits x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic x86/mm: Remove pointless checks in vmalloc_fault x86/platform/intel-mid: Add special handling for ACPI HW reduced platforms ACPI, x86/boot: Introduce the ->reduced_hw_early_init() ACPI callback ACPI, x86/boot: Split out acpi_generic_reduce_hw_init() and export x86/pconfig: Provide defines and helper to run MKTME_KEY_PROG leaf x86/pconfig: Detect PCONFIG targets x86/tme: Detect if TME and MKTME is activated by BIOS x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G x86/boot/compressed/64: Use page table in trampoline memory x86/boot/compressed/64: Use stack from trampoline memory x86/boot/compressed/64: Make sure we have a 32-bit code segment x86/mm: Do not use paravirtualized calls in native_set_p4d() kdump, vmcoreinfo: Export pgtable_l5_enabled value x86/boot/compressed/64: Prepare new top-level page table for trampoline x86/boot/compressed/64: Set up trampoline memory x86/boot/compressed/64: Save and restore trampoline memory ...
2018-04-02Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups and msr updates from Ingo Molnar: "The main change is a performance/latency improvement to /dev/msr access. The rest are misc cleanups" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/msr: Make rdmsrl_safe_on_cpu() scheduling safe as well x86/cpuid: Allow cpuid_read() to schedule x86/msr: Allow rdmsr_safe_on_cpu() to schedule x86/rtc: Stop using deprecated functions x86/dumpstack: Unify show_regs() x86/fault: Do not print IP in show_fault_oops() x86/MSR: Move native_* variants to msr.h
2018-03-15x86/mm: Remove pointless checks in vmalloc_faultToshi Kani1-39/+17
vmalloc_fault() sets user's pgd or p4d from the kernel page table. Once it's set, all tables underneath are identical. There is no point of following the same page table with two separate pointers and make sure they see the same with BUG(). Remove the pointless checks in vmalloc_fault(). Also rename the kernel pgd/p4d pointers to pgd_k/p4d_k so that their names are consistent in the file. Suggested-by: Andy Lutomirski <[email protected]> Signed-off-by: Toshi Kani <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: Borislav Petkov <[email protected]> Cc: Gratian Crisan <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-03-14Merge branch 'x86/urgent' into x86/mm to pick up dependenciesThomas Gleixner1-3/+3
2018-03-14x86/mm: Fix vmalloc_fault to use pXd_largeToshi Kani1-3/+3
Gratian Crisan reported that vmalloc_fault() crashes when CONFIG_HUGETLBFS is not set since the function inadvertently uses pXn_huge(), which always return 0 in this case. ioremap() does not depend on CONFIG_HUGETLBFS. Fix vmalloc_fault() to call pXd_large() instead. Fixes: f4eafd8bcd52 ("x86/mm: Fix vmalloc_fault() to handle large pages properly") Reported-by: Gratian Crisan <[email protected]> Signed-off-by: Toshi Kani <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Borislav Petkov <[email protected]> Cc: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-03-12Merge branch 'x86/pti' into x86/mm, to pick up dependenciesIngo Molnar1-4/+0
Signed-off-by: Ingo Molnar <[email protected]>
2018-03-08x86/fault: Do not print IP in show_fault_oops()Borislav Petkov1-1/+0
... because __show_regs() already does that. Signed-off-by: Borislav Petkov <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Andy Lutomirski <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2018-02-20x86/mm: Remove stale comment about KMEMCHECKJann Horn1-4/+0
This comment referred to a conditional call to kmemcheck_hide() that was here until commit 4950276672fc ("kmemcheck: remove annotations"). Now that kmemcheck has been removed, it doesn't make sense anymore. Signed-off-by: Jann Horn <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2018-02-16x86/mm: Replace compile-time checks for 5-level paging with runtime-time checksKirill A. Shutemov1-2/+2
This patch converts the of CONFIG_X86_5LEVEL check to runtime checks for p4d folding. Signed-off-by: Kirill A. Shutemov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arjan van de Ven <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Woodhouse <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2018-01-26x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernelsAndy Lutomirski1-13/+9
On a 5-level kernel, if a non-init mm has a top-level entry, it needs to match init_mm's, but the vmalloc_fault() code skipped over the BUG_ON() that would have checked it. While we're at it, get rid of the rather confusing 4-level folded "pgd" logic. Cleans-up: b50858ce3e2a ("x86/mm/vmalloc: Add 5-level paging support") Signed-off-by: Andy Lutomirski <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: Konstantin Khlebnikov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Neil Berrington <[email protected]> Link: https://lkml.kernel.org/r/2ae598f8c279b0a29baf75df207e6f2fdddc0a1b.1516914529.git.luto@kernel.org
2018-01-14x86/mm/pkeys: Fix fill_sig_info_pkeyEric W. Biederman1-3/+4
SEGV_PKUERR is a signal specific si_code which happens to have the same numeric value as several others: BUS_MCEERR_AR, ILL_ILLTRP, FPE_FLTOVF, TRAP_HWBKPT, CLD_TRAPPED, POLL_ERR, SEGV_THREAD_ID, as such it is not safe to just test the si_code the signal number must also be tested to prevent a false positive in fill_sig_info_pkey. This error was by inspection, and BUS_MCEERR_AR appears to be a real candidate for confusion. So pass in si_signo and check for SIG_SEGV to verify that it is actually a SEGV_PKUERR Fixes: 019132ff3daf ("x86/mm/pkeys: Fill in pkey field in siginfo") Signed-off-by: "Eric W. Biederman" <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: Dave Hansen <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Al Viro <[email protected]> cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2017-12-19Do not hash userspace addresses in fault handlersKees Cook1-1/+1
The hashing of %p was designed to restrict kernel addresses. There is no reason to hash the userspace values seen during a segfault report, so switch these to %px. (Some architectures already use %lx.) Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p") Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-12-05x86: don't hash faulting address in oops printoutLinus Torvalds1-1/+1
Things like this will probably keep showing up for other architectures and other special cases. I actually thought we already used %lx for this, and that is indeed _historically_ the case, but we moved to %p when merging the 32-bit and 64-bit cases as a convenient way to get the formatting right (ie automatically picking "%08lx" vs "%016lx" based on register size). So just turn this %p into %px. Reported-by: Sergey Senozhatsky <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-11-15kmemcheck: remove annotationsLevin, Alexander (Sasha Levin)1-6/+0
Patch series "kmemcheck: kill kmemcheck", v2. As discussed at LSF/MM, kill kmemcheck. KASan is a replacement that is able to work without the limitation of kmemcheck (single CPU, slow). KASan is already upstream. We are also not aware of any users of kmemcheck (or users who don't consider KASan as a suitable replacement). The only objection was that since KASAN wasn't supported by all GCC versions provided by distros at that time we should hold off for 2 years, and try again. Now that 2 years have passed, and all distros provide gcc that supports KASAN, kill kmemcheck again for the very same reasons. This patch (of 4): Remove kmemcheck annotations, and calls to kmemcheck from the kernel. [[email protected]: correctly remove kmemcheck call from dma_map_sg_attrs] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Sasha Levin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Eric W. Biederman <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Tim Hansen <[email protected]> Cc: Vegard Nossum <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-11-07Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflictsIngo Molnar1-1/+11
Conflicts: arch/x86/kernel/cpu/Makefile Signed-off-by: Ingo Molnar <[email protected]>
2017-11-02Merge tag 'spdx_identifiers-4.14-rc8' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull initial SPDX identifiers from Greg KH: "License cleanup: add SPDX license identifiers to some files Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Philippe Ombredanne <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>" * tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: License cleanup: add SPDX license identifier to uapi header files with a license License cleanup: add SPDX license identifier to uapi header files with no license License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Philippe Ombredanne <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-11-01x86/mm: Relocate page fault error codes to traps.hRicardo Neri1-54/+34
Up to this point, only fault.c used the definitions of the page fault error codes. Thus, it made sense to keep them within such file. Other portions of code might be interested in those definitions too. For instance, the User- Mode Instruction Prevention emulation code will use such definitions to emulate a page fault when it is unable to successfully copy the results of the emulated instructions to user space. While relocating the error code enumeration, the prefix X86_ is used to make it consistent with the rest of the definitions in traps.h. Of course, code using the enumeration had to be updated as well. No functional changes were performed. Signed-off-by: Ricardo Neri <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> Reviewed-by: Andy Lutomirski <[email protected]> Cc: "Michael S. Tsirkin" <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Dave Hansen <[email protected]> Cc: [email protected] Cc: Paul Gortmaker <[email protected]> Cc: Huang Rui <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: "Ravi V. Shankar" <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Chen Yucong <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Andrew Morton <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Link: https://lkml.kernel.org/r/1509135945-13762-2-git-send-email-ricardo.neri-calderon@linux.intel.com
2017-11-01x86/mm: fix use-after-free of vma during userfaultfd faultVlastimil Babka1-1/+10
Syzkaller with KASAN has reported a use-after-free of vma->vm_flags in __do_page_fault() with the following reproducer: mmap(&(0x7f0000000000/0xfff000)=nil, 0xfff000, 0x3, 0x32, 0xffffffffffffffff, 0x0) mmap(&(0x7f0000011000/0x3000)=nil, 0x3000, 0x1, 0x32, 0xffffffffffffffff, 0x0) r0 = userfaultfd(0x0) ioctl$UFFDIO_API(r0, 0xc018aa3f, &(0x7f0000002000-0x18)={0xaa, 0x0, 0x0}) ioctl$UFFDIO_REGISTER(r0, 0xc020aa00, &(0x7f0000019000)={{&(0x7f0000012000/0x2000)=nil, 0x2000}, 0x1, 0x0}) r1 = gettid() syz_open_dev$evdev(&(0x7f0000013000-0x12)="2f6465762f696e7075742f6576656e742300", 0x0, 0x0) tkill(r1, 0x7) The vma should be pinned by mmap_sem, but handle_userfault() might (in a return to userspace scenario) release it and then acquire again, so when we return to __do_page_fault() (with other result than VM_FAULT_RETRY), the vma might be gone. Specifically, per Andrea the scenario is "A return to userland to repeat the page fault later with a VM_FAULT_NOPAGE retval (potentially after handling any pending signal during the return to userland). The return to userland is identified whenever FAULT_FLAG_USER|FAULT_FLAG_KILLABLE are both set in vmf->flags" However, since commit a3c4fb7c9c2e ("x86/mm: Fix fault error path using unsafe vma pointer") there is a vma_pkey() read of vma->vm_flags after that point, which can thus become use-after-free. Fix this by moving the read before calling handle_mm_fault(). Reported-by: syzbot <bot+6a5269ce759a7bb12754ed9622076dc93f65a1f6@syzkaller.appspotmail.com> Reported-by: Dmitry Vyukov <[email protected]> Suggested-by: Kirill A. Shutemov <[email protected]> Fixes: 3c4fb7c9c2e ("x86/mm: Fix fault error path using unsafe vma pointer") Reviewed-by: Andrea Arcangeli <[email protected]> Signed-off-by: Vlastimil Babka <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-09-25x86/mm: Fix fault error path using unsafe vma pointerLaurent Dufour1-23/+24
commit 7b2d0dbac489 ("x86/mm/pkeys: Pass VMA down in to fault signal generation code") passes down a vma pointer to the error path, but that is done once the mmap_sem is released when calling mm_fault_error() from __do_page_fault(). This is dangerous as the vma structure is no more safe to be used once the mmap_sem has been released. As only the protection key value is required in the error processing, we could just pass down this value. Fix it by passing a pointer to a protection key value down to the fault signal generation code. The use of a pointer allows to keep the check generating a warning message in fill_sig_info_pkey() when the vma was not known. If the pointer is valid, the protection value can be accessed by deferencing the pointer. [ tglx: Made *pkey u32 as that's the type which is passed in siginfo ] Fixes: 7b2d0dbac489 ("x86/mm/pkeys: Pass VMA down in to fault signal generation code") Signed-off-by: Laurent Dufour <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: Dave Hansen <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected]
2017-09-23x86/asm: Fix inline asm call constraints for ClangJosh Poimboeuf1-2/+1
For inline asm statements which have a CALL instruction, we list the stack pointer as a constraint to convince GCC to ensure the frame pointer is set up first: static inline void foo() { register void *__sp asm(_ASM_SP); asm("call bar" : "+r" (__sp)) } Unfortunately, that pattern causes Clang to corrupt the stack pointer. The fix is easy: convert the stack pointer register variable to a global variable. It should be noted that the end result is different based on the GCC version. With GCC 6.4, this patch has exactly the same result as before: defconfig defconfig-nofp distro distro-nofp before 9820389 9491555 8816046 8516940 after 9820389 9491555 8816046 8516940 With GCC 7.2, however, GCC's behavior has changed. It now changes its behavior based on the conversion of the register variable to a global. That somehow convinces it to *always* set up the frame pointer before inserting *any* inline asm. (Therefore, listing the variable as an output constraint is a no-op and is no longer necessary.) It's a bit overkill, but the performance impact should be negligible. And in fact, there's a nice improvement with frame pointers disabled: defconfig defconfig-nofp distro distro-nofp before 9796316 9468236 9076191 8790305 after 9796957 9464267 9076381 8785949 So in summary, while listing the stack pointer as an output constraint is no longer necessary for newer versions of GCC, it's still needed for older versions. Suggested-by: Andrey Ryabinin <[email protected]> Reported-by: Matthias Kaehlcke <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Dmitriy Vyukov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Miguel Bernal Marin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/3db862e970c432ae823cf515c52b54fec8270e0e.1505942196.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <[email protected]>
2017-09-04Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds1-36/+13
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Thomas Gleixner: "This update provides: - Cleanup of the IDT management including the removal of the extra tracing IDT. A first step to cleanup the vector management code. - The removal of the paravirt op adjust_exception_frame. This is a XEN specific issue, but merged through this branch to avoid nasty merge collisions - Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has disabled the TSC DEADLINE timer in CPUID. - Adjust a debug message in the ioapic code to print out the information correctly" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits) x86/idt: Fix the X86_TRAP_BP gate x86/xen: Get rid of paravirt op adjust_exception_frame x86/eisa: Add missing include x86/idt: Remove superfluous ALIGNment x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature x86/idt: Remove the tracing IDT leftovers x86/idt: Hide set_intr_gate() x86/idt: Simplify alloc_intr_gate() x86/idt: Deinline setup functions x86/idt: Remove unused functions/inlines x86/idt: Move interrupt gate initialization to IDT code x86/idt: Move APIC gate initialization to tables x86/idt: Move regular trap init to tables x86/idt: Move IST stack based traps to table init x86/idt: Move debug stack init to table based x86/idt: Switch early trap init to IDT tables x86/idt: Prepare for table based init x86/idt: Move early IDT setup out of 32-bit asm x86/idt: Move early IDT handler setup to IDT code x86/idt: Consolidate IDT invalidation ...
2017-08-31x86/mm: Use pr_cont() in dump_pagetable()Jan Beulich1-11/+15
The lack of newlines in preceding format strings is a clear indication that these were meant to be continuations of one another, and indeed output ends up quite a bit more compact (and readable) that way. Switch other plain printk()-s in the function instances to pr_info(), as requested. Signed-off-by: Jan Beulich <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-08-29x86/tracing: Disentangle pagefault and resched IPI tracing keyThomas Gleixner1-1/+1
The pagefault and the resched IPI handler are the only ones where it is worth to optimize the code further in case tracepoints are disabled. But it makes no sense to have a single static key for both. Seperate the static keys so the facilities are handled seperately. Signed-off-by: Thomas Gleixner <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-08-29x86/traps: Simplify pagefault tracing logicThomas Gleixner1-36/+13
Make use of the new irqvector tracing static key and remove the duplicated trace_do_pagefault() implementation. If irq vector tracing is disabled, then the overhead of this is a single NOP5, which is a reasonable tradeoff to avoid duplicated code and the unholy macro mess. Signed-off-by: Thomas Gleixner <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-06-13x86/mm: Split read_cr3() into read_cr3_pa() and __read_cr3()Andy Lutomirski1-5/+5
The kernel has several code paths that read CR3. Most of them assume that CR3 contains the PGD's physical address, whereas some of them awkwardly use PHYSICAL_PAGE_MASK to mask off low bits. Add explicit mask macros for CR3 and convert all of the CR3 readers. This will keep them from breaking when PCID is enabled. Signed-off-by: Andy Lutomirski <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tom Lendacky <[email protected]> Cc: xen-devel <[email protected]> Link: http://lkml.kernel.org/r/883f8fb121f4616c1c1427ad87350bb2f5ffeca1.1497288170.git.luto@kernel.org Signed-off-by: Ingo Molnar <[email protected]>
2017-03-14x86/mm/vmalloc: Add 5-level paging supportKirill A. Shutemov1-3/+24
Modify vmalloc_fault() to handle additional page table level. With 4-level paging, copying happens on p4d level, as we have pgd_none() always false if p4d_t is folded. Signed-off-by: Kirill A. Shutemov <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-14x86/mm: Convert trivial cases of page table walk to 5-level pagingKirill A. Shutemov1-6/+33
This patch only covers simple cases. Less trivial cases will be converted with separate patches. Signed-off-by: Kirill A. Shutemov <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/task_stack.h> We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-12-15x86/mm: Drop unused argument 'removed' from sync_global_pgds()Kirill A. Shutemov1-1/+1
Since commit af2cf278ef4f ("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()") there are no callers of sync_global_pgds() which set the 'removed' argument to 1. Remove the argument and the related conditionals in the function. Signed-off-by: Kirill A. Shutemov <[email protected]> Cc: Andy Lutomirski <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2016-10-25x86/dumpstack: Remove kernel text addresses from stack dumpJosh Poimboeuf1-2/+1
Printing kernel text addresses in stack dumps is of questionable value, especially now that address randomization is becoming common. It can be a security issue because it leaks kernel addresses. It also affects the usefulness of the stack dump. Linus says: "I actually spend time cleaning up commit messages in logs, because useless data that isn't actually information (random hex numbers) is actively detrimental. It makes commit logs less legible. It also makes it harder to parse dumps. It's not useful. That makes it actively bad. I probably look at more oops reports than most people. I have not found the hex numbers useful for the last five years, because they are just randomized crap. The stack content thing just makes code scroll off the screen etc, for example." The only real downside to removing these addresses is that they can be used to disambiguate duplicate symbol names. However such cases are rare, and the context of the stack dump should be enough to be able to figure it out. There's now a 'faddr2line' script which can be used to convert a function address to a file name and line: $ ./scripts/faddr2line ~/k/vmlinux write_sysrq_trigger+0x51/0x60 write_sysrq_trigger+0x51/0x60: write_sysrq_trigger at drivers/tty/sysrq.c:1098 Or gdb can be used: $ echo "list *write_sysrq_trigger+0x51" |gdb ~/k/vmlinux |grep "is in" (gdb) 0xffffffff815b5d83 is in driver_probe_device (/home/jpoimboe/git/linux/drivers/base/dd.c:378). (But note that when there are duplicate symbol names, gdb will only show the first symbol it finds. faddr2line is recommended over gdb because it handles duplicates and it also does function size checking.) Here's an example of what a stack dump looks like after this change: BUG: unable to handle kernel NULL pointer dereference at (null) IP: sysrq_handle_crash+0x45/0x80 PGD 36bfa067 [ 29.650644] PUD 7aca3067 Oops: 0002 [#1] PREEMPT SMP Modules linked in: ... CPU: 1 PID: 786 Comm: bash Tainted: G E 4.9.0-rc1+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014 task: ffff880078582a40 task.stack: ffffc90000ba8000 RIP: 0010:sysrq_handle_crash+0x45/0x80 RSP: 0018:ffffc90000babdc8 EFLAGS: 00010296 RAX: ffff880078582a40 RBX: 0000000000000063 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000292 RBP: ffffc90000babdc8 R08: 0000000b31866061 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000007 R14: ffffffff81ee8680 R15: 0000000000000000 FS: 00007ffb43869700(0000) GS:ffff88007d400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007a3e9000 CR4: 00000000001406e0 Stack: ffffc90000babe00 ffffffff81572d08 ffffffff81572bd5 0000000000000002 0000000000000000 ffff880079606600 00007ffb4386e000 ffffc90000babe20 ffffffff81573201 ffff880036a3fd00 fffffffffffffffb ffffc90000babe40 Call Trace: __handle_sysrq+0x138/0x220 ? __handle_sysrq+0x5/0x220 write_sysrq_trigger+0x51/0x60 proc_reg_write+0x42/0x70 __vfs_write+0x37/0x140 ? preempt_count_sub+0xa1/0x100 ? __sb_start_write+0xf5/0x210 ? vfs_write+0x183/0x1a0 vfs_write+0xb8/0x1a0 SyS_write+0x58/0xc0 entry_SYSCALL_64_fastpath+0x1f/0xc2 RIP: 0033:0x7ffb42f55940 RSP: 002b:00007ffd33bb6b18 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000046 RCX: 00007ffb42f55940 RDX: 0000000000000002 RSI: 00007ffb4386e000 RDI: 0000000000000001 RBP: 0000000000000011 R08: 00007ffb4321ea40 R09: 00007ffb43869700 R10: 00007ffb43869700 R11: 0000000000000246 R12: 0000000000778a10 R13: 00007ffd33bb5c00 R14: 0000000000000007 R15: 0000000000000010 Code: 34 e8 d0 34 bc ff 48 c7 c2 3b 2b 57 81 be 01 00 00 00 48 c7 c7 e0 dd e5 81 e8 a8 55 ba ff c7 05 0e 3f de 00 01 00 00 00 0f ae f8 <c6> 04 25 00 00 00 00 01 5d c3 e8 4c 49 bc ff 84 c0 75 c3 48 c7 RIP: sysrq_handle_crash+0x45/0x80 RSP: ffffc90000babdc8 CR2: 0000000000000000 Suggested-by: Linus Torvalds <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/69329cb29b8f324bb5fcea14d61d224807fb6488.1477405374.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <[email protected]>
2016-10-11Merge branch 'work.uaccess2' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull uaccess.h prepwork from Al Viro: "Preparations to tree-wide switch to use of linux/uaccess.h (which, obviously, will allow to start unifying stuff for real). The last step there, ie PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ `git grep -l "$PATT"|grep -v ^include/linux/uaccess.h` is not taken here - I would prefer to do it once just before or just after -rc1. However, everything should be ready for it" * 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: remove a stray reference to asm/uaccess.h in docs sparc64: separate extable_64.h, switch elf_64.h to it score: separate extable.h, switch module.h to it mips: separate extable.h, switch module.h to it x86: separate extable.h, switch sections.h to it remove stray include of asm/uaccess.h from cacheflush.h mn10300: remove a bogus processor.h->uaccess.h include xtensa: split uaccess.h into C and asm sides bonding: quit messing with IOCTL kill __kernel_ds_p off mn10300: finish verify_area() off frv: move HAVE_ARCH_UNMAPPED_AREA to pgtable.h exceptions: detritus removal
2016-10-10Merge branch 'mm-pkeys-for-linus' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull protection keys syscall interface from Thomas Gleixner: "This is the final step of Protection Keys support which adds the syscalls so user space can actually allocate keys and protect memory areas with them. Details and usage examples can be found in the documentation. The mm side of this has been acked by Mel" * 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/pkeys: Update documentation x86/mm/pkeys: Do not skip PKRU register if debug registers are not used x86/pkeys: Fix pkeys build breakage for some non-x86 arches x86/pkeys: Add self-tests x86/pkeys: Allow configuration of init_pkru x86/pkeys: Default to a restrictive init PKRU pkeys: Add details of system call use to Documentation/ generic syscalls: Wire up memory protection keys syscalls x86: Wire up protection keys system calls x86/pkeys: Allocation/free syscalls x86/pkeys: Make mprotect_key() mask off additional vm_flags mm: Implement new pkey_mprotect() system call x86/pkeys: Add fault handling for PF_PK page fault bit
2016-10-03Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Header file and a wrapper functions cleanup" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Migrate exception table users off module.h and onto extable.h x86: Clean up various simple wrapper functions
2016-09-27exceptions: detritus removalAl Viro1-1/+1
externs and defines for stuff that is never used Signed-off-by: Al Viro <[email protected]>
2016-09-20x86: Migrate exception table users off module.h and onto extable.hPaul Gortmaker1-1/+1
These files were only including module.h for exception table related functions. We've now separated that content out into its own file "extable.h" so now move over to that and avoid all the extra header content in module.h that we don't really need to compile these files. Signed-off-by: Paul Gortmaker <[email protected]> Acked-by: Ingo Molnar <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2016-09-09x86/pkeys: Add fault handling for PF_PK page fault bitDave Hansen1-0/+9
PF_PK means that a memory access violated the protection key access restrictions. It is unconditionally an access_error() because the permissions set on the VMA don't matter (the PKRU value overrides it), and we never "resolve" PK faults (like how a COW can "resolve write fault). Signed-off-by: Dave Hansen <[email protected]> Acked-by: Mel Gorman <[email protected]> Cc: [email protected] Cc: Dave Hansen <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2016-09-08x86/mm: Improve stack-overflow #PF handlingAndy Lutomirski1-0/+32
If we get a page fault indicating kernel stack overflow, invoke handle_stack_overflow(). To prevent us from overflowing the stack again while handling the overflow (because we are likely to have very little stack space left), call handle_stack_overflow() on the double-fault stack. Signed-off-by: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/6d6cf96b3fb9b4c9aa303817e1dc4de0c7c36487.1472603235.git.luto@kernel.org [ Minor edit. ] Signed-off-by: Ingo Molnar <[email protected]>
2016-07-26mm: do not pass mm_struct into handle_mm_faultKirill A. Shutemov1-1/+1
We always have vma->vm_mm around. Link: http://lkml.kernel.org/r/1466021202-61880-8-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-07-15x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_errIngo Molnar1-1/+1
Rename it to match the thread_struct::uaccess_err pattern and also because it was too long. Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-07-15x86/uaccess: Move thread_info::uaccess_err and ↵Andy Lutomirski1-1/+1
thread_info::sig_on_uaccess_err to thread_struct struct thread_info is a legacy mess. To prepare for its partial removal, move the uaccess control fields out -- they're straightforward. Signed-off-by: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/d0ac4d01c8e4d4d756264604e47445d5acc7900e.1468527351.git.luto@kernel.org Signed-off-by: Ingo Molnar <[email protected]>
2016-07-15x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mmAndy Lutomirski1-1/+1
If we get a vmalloc fault while current->active_mm->pgd doesn't match CR3, we'll crash without this change. I've seen this failure mode on heavily instrumented kernels with virtually mapped stacks. Signed-off-by: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/4650d7674185f165ed8fdf9ac4c5c35c5c179ba8.1468527351.git.luto@kernel.org Signed-off-by: Ingo Molnar <[email protected]>
2016-05-20x86/mm: Switch from TASK_SIZE to TASK_SIZE_MAX in the page fault codeAndy Lutomirski1-3/+8
x86's page fault handlers had two TASK_SIZE uses that should have been TASK_SIZE_MAX. I don't think that either one had a visible effect, but this makes the code clearer and should save a few bytes of text. (And I eventually want to eradicate TASK_SIZE. This will help.) Reported-by: Cyrill Gorcunov <[email protected]> Signed-off-by: Andy Lutomirski <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Dmitry Safonov <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Pavel Emelyanov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ruslan Kabatsayev <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/1242fb23b0d05c3069dbf5758ac55d26bc114bef.1462914565.git.luto@kernel.org Signed-off-by: Ingo Molnar <[email protected]>
2016-03-20Merge branch 'mm-pkeys-for-linus' of ↵Linus Torvalds1-22/+128
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 protection key support from Ingo Molnar: "This tree adds support for a new memory protection hardware feature that is available in upcoming Intel CPUs: 'protection keys' (pkeys). There's a background article at LWN.net: https://lwn.net/Articles/643797/ The gist is that protection keys allow the encoding of user-controllable permission masks in the pte. So instead of having a fixed protection mask in the pte (which needs a system call to change and works on a per page basis), the user can map a (handful of) protection mask variants and can change the masks runtime relatively cheaply, without having to change every single page in the affected virtual memory range. This allows the dynamic switching of the protection bits of large amounts of virtual memory, via user-space instructions. It also allows more precise control of MMU permission bits: for example the executable bit is separate from the read bit (see more about that below). This tree adds the MM infrastructure and low level x86 glue needed for that, plus it adds a high level API to make use of protection keys - if a user-space application calls: mmap(..., PROT_EXEC); or mprotect(ptr, sz, PROT_EXEC); (note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice this special case, and will set a special protection key on this memory range. It also sets the appropriate bits in the Protection Keys User Rights (PKRU) register so that the memory becomes unreadable and unwritable. So using protection keys the kernel is able to implement 'true' PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies PROT_READ as well. Unreadable executable mappings have security advantages: they cannot be read via information leaks to figure out ASLR details, nor can they be scanned for ROP gadgets - and they cannot be used by exploits for data purposes either. We know about no user-space code that relies on pure PROT_EXEC mappings today, but binary loaders could start making use of this new feature to map binaries and libraries in a more secure fashion. There is other pending pkeys work that offers more high level system call APIs to manage protection keys - but those are not part of this pull request. Right now there's a Kconfig that controls this feature (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled (like most x86 CPU feature enablement code that has no runtime overhead), but it's not user-configurable at the moment. If there's any serious problem with this then we can make it configurable and/or flip the default" * 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) x86/mm/pkeys: Fix mismerge of protection keys CPUID bits mm/pkeys: Fix siginfo ABI breakage caused by new u64 field x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA mm/core, x86/mm/pkeys: Add execute-only protection keys support x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags x86/mm/pkeys: Allow kernel to modify user pkey rights register x86/fpu: Allow setting of XSAVE state x86/mm: Factor out LDT init from context init mm/core, x86/mm/pkeys: Add arch_validate_pkey() mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits() x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU x86/mm/pkeys: Add Kconfig prompt to existing config option x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps x86/mm/pkeys: Dump PKRU with other kernel registers mm/core, x86/mm/pkeys: Differentiate instruction fetches x86/mm/pkeys: Optimize fault handling in access_error() mm/core: Do not enforce PKEY permissions on remote mm access um, pkeys: Add UML arch_*_access_permitted() methods mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys x86/mm/gup: Simplify get_user_pages() PTE bit handling ...
2016-03-08Merge branch 'linus' into ras/core, to pick up fixesIngo Molnar1-4/+11
Signed-off-by: Ingo Molnar <[email protected]>
2016-03-03x86/mm/pkeys: Fix access_error() denial of writes to write-only VMADave Hansen1-18/+0
Andrey Wagin reported that a simple test case was broken by: 2b5f7d013fc ("mm/core, x86/mm/pkeys: Add execute-only protection keys support") This test case creates an unreadable VMA and my patch assumed that all writes must be to readable VMAs. The simplest fix for this is to remove the pkey-related bits in access_error(). For execute-only support, I believe the existing version is sufficient because the permissions we are trying to enforce are entirely expressed in vma->vm_flags. We just depend on pkeys to get *an* exception, it does not matter that PF_PK was set, or even what state PKRU is in. I will re-add the necessary bits with the full pkeys implementation that includes the new syscalls. The three cases that matter are: 1. If a write to an execute-only VMA occurs, we will see PF_WRITE set, but !VM_WRITE on the VMA, and return 1. All execute-only VMAs have VM_WRITE clear by definition. 2. If a read occurs on a present PTE, we will fall in to the "read, present" case and return 1. 3. If a read occurs to a non-present PTE, we will miss the "read, not present" case, because the execute-only VMA will have VM_EXEC set, and we will properly return 0 allowing the PTE to be populated. Test program: int main() { int *p; p = mmap(NULL, 4096, PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); p[0] = 1; return 0; } Reported-by: Andrey Wagin <[email protected]>, Signed-off-by: Dave Hansen <[email protected]> Acked-by: Kirill A. Shutemov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Fixes: 62b5f7d013fc ("mm/core, x86/mm/pkeys: Add execute-only protection keys support") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>