- 06 6月, 2018 1 次提交
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由 Mathieu Desnoyers 提交于
Expose a new system call allowing each thread to register one userspace memory area to be used as an ABI between kernel and user-space for two purposes: user-space restartable sequences and quick access to read the current CPU number value from user-space. * Restartable sequences (per-cpu atomics) Restartables sequences allow user-space to perform update operations on per-cpu data without requiring heavy-weight atomic operations. The restartable critical sections (percpu atomics) work has been started by Paul Turner and Andrew Hunter. It lets the kernel handle restart of critical sections. [1] [2] The re-implementation proposed here brings a few simplifications to the ABI which facilitates porting to other architectures and speeds up the user-space fast path. Here are benchmarks of various rseq use-cases. Test hardware: arm32: ARMv7 Processor rev 4 (v7l) "Cubietruck", 2-core x86-64: Intel E5-2630 v3@2.40GHz, 16-core, hyperthreading The following benchmarks were all performed on a single thread. * Per-CPU statistic counter increment getcpu+atomic (ns/op) rseq (ns/op) speedup arm32: 344.0 31.4 11.0 x86-64: 15.3 2.0 7.7 * LTTng-UST: write event 32-bit header, 32-bit payload into tracer per-cpu buffer getcpu+atomic (ns/op) rseq (ns/op) speedup arm32: 2502.0 2250.0 1.1 x86-64: 117.4 98.0 1.2 * liburcu percpu: lock-unlock pair, dereference, read/compare word getcpu+atomic (ns/op) rseq (ns/op) speedup arm32: 751.0 128.5 5.8 x86-64: 53.4 28.6 1.9 * jemalloc memory allocator adapted to use rseq Using rseq with per-cpu memory pools in jemalloc at Facebook (based on rseq 2016 implementation): The production workload response-time has 1-2% gain avg. latency, and the P99 overall latency drops by 2-3%. * Reading the current CPU number Speeding up reading the current CPU number on which the caller thread is running is done by keeping the current CPU number up do date within the cpu_id field of the memory area registered by the thread. This is done by making scheduler preemption set the TIF_NOTIFY_RESUME flag on the current thread. Upon return to user-space, a notify-resume handler updates the current CPU value within the registered user-space memory area. User-space can then read the current CPU number directly from memory. Keeping the current cpu id in a memory area shared between kernel and user-space is an improvement over current mechanisms available to read the current CPU number, which has the following benefits over alternative approaches: - 35x speedup on ARM vs system call through glibc - 20x speedup on x86 compared to calling glibc, which calls vdso executing a "lsl" instruction, - 14x speedup on x86 compared to inlined "lsl" instruction, - Unlike vdso approaches, this cpu_id value can be read from an inline assembly, which makes it a useful building block for restartable sequences. - The approach of reading the cpu id through memory mapping shared between kernel and user-space is portable (e.g. ARM), which is not the case for the lsl-based x86 vdso. On x86, yet another possible approach would be to use the gs segment selector to point to user-space per-cpu data. This approach performs similarly to the cpu id cache, but it has two disadvantages: it is not portable, and it is incompatible with existing applications already using the gs segment selector for other purposes. Benchmarking various approaches for reading the current CPU number: ARMv7 Processor rev 4 (v7l) Machine model: Cubietruck - Baseline (empty loop): 8.4 ns - Read CPU from rseq cpu_id: 16.7 ns - Read CPU from rseq cpu_id (lazy register): 19.8 ns - glibc 2.19-0ubuntu6.6 getcpu: 301.8 ns - getcpu system call: 234.9 ns x86-64 Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz: - Baseline (empty loop): 0.8 ns - Read CPU from rseq cpu_id: 0.8 ns - Read CPU from rseq cpu_id (lazy register): 0.8 ns - Read using gs segment selector: 0.8 ns - "lsl" inline assembly: 13.0 ns - glibc 2.19-0ubuntu6 getcpu: 16.6 ns - getcpu system call: 53.9 ns - Speed (benchmark taken on v8 of patchset) Running 10 runs of hackbench -l 100000 seems to indicate, contrary to expectations, that enabling CONFIG_RSEQ slightly accelerates the scheduler: Configuration: 2 sockets * 8-core Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz (directly on hardware, hyperthreading disabled in BIOS, energy saving disabled in BIOS, turboboost disabled in BIOS, cpuidle.off=1 kernel parameter), with a Linux v4.6 defconfig+localyesconfig, restartable sequences series applied. * CONFIG_RSEQ=n avg.: 41.37 s std.dev.: 0.36 s * CONFIG_RSEQ=y avg.: 40.46 s std.dev.: 0.33 s - Size On x86-64, between CONFIG_RSEQ=n/y, the text size increase of vmlinux is 567 bytes, and the data size increase of vmlinux is 5696 bytes. [1] https://lwn.net/Articles/650333/ [2] http://www.linuxplumbersconf.org/2013/ocw/system/presentations/1695/original/LPC%20-%20PerCpu%20Atomics.pdfSigned-off-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Joel Fernandes <joelaf@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Watson <davejwatson@fb.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Chris Lameter <cl@linux.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Hunter <ahh@google.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ben Maurer <bmaurer@fb.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-api@vger.kernel.org Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20151027235635.16059.11630.stgit@pjt-glaptop.roam.corp.google.com Link: http://lkml.kernel.org/r/20150624222609.6116.86035.stgit@kitami.mtv.corp.google.com Link: https://lkml.kernel.org/r/20180602124408.8430-3-mathieu.desnoyers@efficios.com
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- 12 5月, 2018 1 次提交
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由 Dmitry Vyukov 提交于
Currently STRUCTLEAK inserts initialization out of live scope of variables from KASAN point of view. This leads to KASAN false positive reports. Prohibit this combination for now. Link: http://lkml.kernel.org/r/20180419172451.104700-1-dvyukov@google.comSigned-off-by: NDmitry Vyukov <dvyukov@google.com> Acked-by: NKees Cook <keescook@chromium.org> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dennis Zhou <dennisszhou@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 08 5月, 2018 1 次提交
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由 Christoph Hellwig 提交于
There is no arch specific code required for dma-debug, so there is no need to opt into the support either. Signed-off-by: NChristoph Hellwig <hch@lst.de> Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
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- 19 4月, 2018 2 次提交
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由 Deepa Dinamani 提交于
Compat functions are now used to support 32 bit time_t in compat mode on 64 bit architectures and in native mode on 32 bit architectures. Introduce COMPAT_32BIT_TIME to conditionally compile these functions. Note that turning off 32 bit time_t support requires more changes on architecture side. For instance, architecure syscall tables need to be updated to drop support for 32 bit time_t syscalls. Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: NArnd Bergmann <arnd@arndb.de>
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由 Deepa Dinamani 提交于
There are a total of 53 system calls (aside from ioctl) that pass a time_t or derived data structure as an argument, and in order to extend time_t to 64-bit, we have to replace them with new system calls and keep providing backwards compatibility. To avoid adding completely new and untested code for this purpose, we introduce a new CONFIG_64BIT_TIME symbol. Every architecture that supports new 64 bit time_t syscalls enables this config. After this is done for all architectures, the CONFIG_64BIT_TIME symbol will be deleted. Signed-off-by: NArnd Bergmann <arnd@arndb.de> Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: NArnd Bergmann <arnd@arndb.de>
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- 26 3月, 2018 1 次提交
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由 Nicholas Piggin 提交于
This removes the old `ld -r` incremental link option, which has not been selected by any architecture since June 2017. Signed-off-by: NNicholas Piggin <npiggin@gmail.com> Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
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- 07 2月, 2018 2 次提交
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由 Kees Cook 提交于
Nearly all modern compilers support a stack-protector option, and nearly all modern distributions enable the kernel stack-protector, so enabling this by default in kernel builds would make sense. However, Kconfig does not have knowledge of available compiler features, so it isn't safe to force on, as this would unconditionally break builds for the compilers or architectures that don't have support. Instead, this introduces a new option, CONFIG_CC_STACKPROTECTOR_AUTO, which attempts to discover the best possible stack-protector available, and will allow builds to proceed even if the compiler doesn't support any stack-protector. This option is made the default so that kernels built with modern compilers will be protected-by-default against stack buffer overflows, avoiding things like the recent BlueBorne attack. Selection of a specific stack-protector option remains available, including disabling it. Additionally, tiny.config is adjusted to use CC_STACKPROTECTOR_NONE, since that's the option with the least code size (and it used to be the default, so we have to explicitly choose it there now). Link: http://lkml.kernel.org/r/1510076320-69931-4-git-send-email-keescook@chromium.orgSigned-off-by: NKees Cook <keescook@chromium.org> Tested-by: NLaura Abbott <labbott@redhat.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Kees Cook 提交于
Various portions of the kernel, especially per-architecture pieces, need to know if the compiler is building with the stack protector. This was done in the arch/Kconfig with 'select', but this doesn't allow a way to do auto-detected compiler support. In preparation for creating an on-if-available default, move the logic for the definition of CONFIG_CC_STACKPROTECTOR into the Makefile. Link: http://lkml.kernel.org/r/1510076320-69931-3-git-send-email-keescook@chromium.orgSigned-off-by: NKees Cook <keescook@chromium.org> Tested-by: NLaura Abbott <labbott@redhat.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 16 1月, 2018 1 次提交
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由 Kees Cook 提交于
While the blocked and saved_sigmask fields of task_struct are copied to userspace (via sigmask_to_save() and setup_rt_frame()), it is always copied with a static length (i.e. sizeof(sigset_t)). The only portion of task_struct that is potentially dynamically sized and may be copied to userspace is in the architecture-specific thread_struct at the end of task_struct. cache object allocation: kernel/fork.c: alloc_task_struct_node(...): return kmem_cache_alloc_node(task_struct_cachep, ...); dup_task_struct(...): ... tsk = alloc_task_struct_node(node); copy_process(...): ... dup_task_struct(...) _do_fork(...): ... copy_process(...) example usage trace: arch/x86/kernel/fpu/signal.c: __fpu__restore_sig(...): ... struct task_struct *tsk = current; struct fpu *fpu = &tsk->thread.fpu; ... __copy_from_user(&fpu->state.xsave, ..., state_size); fpu__restore_sig(...): ... return __fpu__restore_sig(...); arch/x86/kernel/signal.c: restore_sigcontext(...): ... fpu__restore_sig(...) This introduces arch_thread_struct_whitelist() to let an architecture declare specifically where the whitelist should be within thread_struct. If undefined, the entire thread_struct field is left whitelisted. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Laura Abbott <labbott@redhat.com> Cc: "Mickaël Salaün" <mic@digikod.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: NKees Cook <keescook@chromium.org> Acked-by: NRik van Riel <riel@redhat.com>
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- 13 1月, 2018 1 次提交
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由 Masami Hiramatsu 提交于
Since error-injection framework is not limited to be used by kprobes, nor bpf. Other kernel subsystems can use it freely for checking safeness of error-injection, e.g. livepatch, ftrace etc. So this separate error-injection framework from kprobes. Some differences has been made: - "kprobe" word is removed from any APIs/structures. - BPF_ALLOW_ERROR_INJECTION() is renamed to ALLOW_ERROR_INJECTION() since it is not limited for BPF too. - CONFIG_FUNCTION_ERROR_INJECTION is the config item of this feature. It is automatically enabled if the arch supports error injection feature for kprobe or ftrace etc. Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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- 10 1月, 2018 2 次提交
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由 Christoph Hellwig 提交于
phys_to_dma, dma_to_phys and dma_capable are helpers published by architecture code for use of swiotlb and xen-swiotlb only. Drivers are not supposed to use these directly, but use the DMA API instead. Move these to a new asm/dma-direct.h helper, included by a linux/dma-direct.h wrapper that provides the default linear mapping unless the architecture wants to override it. In the MIPS case the existing dma-coherent.h is reused for now as untangling it will take a bit of work. Signed-off-by: NChristoph Hellwig <hch@lst.de> Acked-by: NRobin Murphy <robin.murphy@arm.com>
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由 David Howells 提交于
Construct the init thread stack in the linker script rather than doing it by means of a union so that ia64's init_task.c can be got rid of. The following symbols are then made available from INIT_TASK_DATA() linker script macro: init_thread_union init_stack INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the size of the init stack. init_thread_union is given its own section so that it can be placed into the stack space in the right order. I'm assuming that the ia64 ordering is correct and that the task_struct is first and the thread_info second. Signed-off-by: NDavid Howells <dhowells@redhat.com> Tested-by: NTony Luck <tony.luck@intel.com> Tested-by: Will Deacon <will.deacon@arm.com> (arm64) Tested-by: NPalmer Dabbelt <palmer@sifive.com> Acked-by: NThomas Gleixner <tglx@linutronix.de>
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- 13 12月, 2017 1 次提交
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由 Josef Bacik 提交于
Error injection is sloppy and very ad-hoc. BPF could fill this niche perfectly with it's kprobe functionality. We could make sure errors are only triggered in specific call chains that we care about with very specific situations. Accomplish this with the bpf_override_funciton helper. This will modify the probe'd callers return value to the specified value and set the PC to an override function that simply returns, bypassing the originally probed function. This gives us a nice clean way to implement systematic error injection for all of our code paths. Acked-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
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- 11 11月, 2017 2 次提交
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由 David S. Miller 提交于
NACK'd by x86 maintainer. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Josef Bacik 提交于
Error injection is sloppy and very ad-hoc. BPF could fill this niche perfectly with it's kprobe functionality. We could make sure errors are only triggered in specific call chains that we care about with very specific situations. Accomplish this with the bpf_override_funciton helper. This will modify the probe'd callers return value to the specified value and set the PC to an override function that simply returns, bypassing the originally probed function. This gives us a nice clean way to implement systematic error injection for all of our code paths. Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NJosef Bacik <jbacik@fb.com> Acked-by: NDaniel Borkmann <daniel@iogearbox.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 02 11月, 2017 1 次提交
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由 Greg Kroah-Hartman 提交于
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: NKate Stewart <kstewart@linuxfoundation.org> Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com> Reviewed-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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- 20 10月, 2017 1 次提交
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由 Masami Hiramatsu 提交于
We want to wait for all potentially preempted kprobes trampoline execution to have completed. This guarantees that any freed trampoline memory is not in use by any task in the system anymore. synchronize_rcu_tasks() gives such a guarantee, so use it. Also, this guarantees to wait for all potentially preempted tasks on the instructions which will be replaced with a jump. Since this becomes a problem only when CONFIG_PREEMPT=y, enable CONFIG_TASKS_RCU=y for synchronize_rcu_tasks() in that case. Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org> Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naveen N . Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/150845661962.5443.17724352636247312231.stgit@devboxSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 09 10月, 2017 1 次提交
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由 Ding Tianhong 提交于
The new flag PCI_DEV_FLAGS_NO_RELAXED_ORDERING has been added to indicate that Relaxed Ordering Attributes (RO) should not be used for Transaction Layer Packets (TLP) targeted toward these affected Root Port, it will clear the bit4 in the PCIe Device Control register, so the PCIe device drivers could query PCIe configuration space to determine if it can send TLPs to Root Port with the Relaxed Ordering Attributes set. With this new flag we don't need the config ARCH_WANT_RELAX_ORDER to control the Relaxed Ordering Attributes for the ixgbe drivers just like the commit 1a8b6d76 ("net:add one common config...") did, so revert this commit. Signed-off-by: NDing Tianhong <dingtianhong@huawei.com> Tested-by: NAndrew Bowers <andrewx.bowers@intel.com> Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
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- 17 8月, 2017 1 次提交
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由 Kees Cook 提交于
This implements refcount_t overflow protection on x86 without a noticeable performance impact, though without the fuller checking of REFCOUNT_FULL. This is done by duplicating the existing atomic_t refcount implementation but with normally a single instruction added to detect if the refcount has gone negative (e.g. wrapped past INT_MAX or below zero). When detected, the handler saturates the refcount_t to INT_MIN / 2. With this overflow protection, the erroneous reference release that would follow a wrap back to zero is blocked from happening, avoiding the class of refcount-overflow use-after-free vulnerabilities entirely. Only the overflow case of refcounting can be perfectly protected, since it can be detected and stopped before the reference is freed and left to be abused by an attacker. There isn't a way to block early decrements, and while REFCOUNT_FULL stops increment-from-zero cases (which would be the state _after_ an early decrement and stops potential double-free conditions), this fast implementation does not, since it would require the more expensive cmpxchg loops. Since the overflow case is much more common (e.g. missing a "put" during an error path), this protection provides real-world protection. For example, the two public refcount overflow use-after-free exploits published in 2016 would have been rendered unexploitable: http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/ http://cyseclabs.com/page?n=02012016 This implementation does, however, notice an unchecked decrement to zero (i.e. caller used refcount_dec() instead of refcount_dec_and_test() and it resulted in a zero). Decrements under zero are noticed (since they will have resulted in a negative value), though this only indicates that a use-after-free may have already happened. Such notifications are likely avoidable by an attacker that has already exploited a use-after-free vulnerability, but it's better to have them reported than allow such conditions to remain universally silent. On first overflow detection, the refcount value is reset to INT_MIN / 2 (which serves as a saturation value) and a report and stack trace are produced. When operations detect only negative value results (such as changing an already saturated value), saturation still happens but no notification is performed (since the value was already saturated). On the matter of races, since the entire range beyond INT_MAX but before 0 is negative, every operation at INT_MIN / 2 will trap, leaving no overflow-only race condition. As for performance, this implementation adds a single "js" instruction to the regular execution flow of a copy of the standard atomic_t refcount operations. (The non-"and_test" refcount_dec() function, which is uncommon in regular refcount design patterns, has an additional "jz" instruction to detect reaching exactly zero.) Since this is a forward jump, it is by default the non-predicted path, which will be reinforced by dynamic branch prediction. The result is this protection having virtually no measurable change in performance over standard atomic_t operations. The error path, located in .text.unlikely, saves the refcount location and then uses UD0 to fire a refcount exception handler, which resets the refcount, handles reporting, and returns to regular execution. This keeps the changes to .text size minimal, avoiding return jumps and open-coded calls to the error reporting routine. Example assembly comparison: refcount_inc() before: .text: ffffffff81546149: f0 ff 45 f4 lock incl -0xc(%rbp) refcount_inc() after: .text: ffffffff81546149: f0 ff 45 f4 lock incl -0xc(%rbp) ffffffff8154614d: 0f 88 80 d5 17 00 js ffffffff816c36d3 ... .text.unlikely: ffffffff816c36d3: 48 8d 4d f4 lea -0xc(%rbp),%rcx ffffffff816c36d7: 0f ff (bad) These are the cycle counts comparing a loop of refcount_inc() from 1 to INT_MAX and back down to 0 (via refcount_dec_and_test()), between unprotected refcount_t (atomic_t), fully protected REFCOUNT_FULL (refcount_t-full), and this overflow-protected refcount (refcount_t-fast): 2147483646 refcount_inc()s and 2147483647 refcount_dec_and_test()s: cycles protections atomic_t 82249267387 none refcount_t-fast 82211446892 overflow, untested dec-to-zero refcount_t-full 144814735193 overflow, untested dec-to-zero, inc-from-zero This code is a modified version of the x86 PAX_REFCOUNT atomic_t overflow defense from the last public patch of PaX/grsecurity, based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Thanks to PaX Team for various suggestions for improvement for repurposing this code to be a refcount-only protection. Signed-off-by: NKees Cook <keescook@chromium.org> Reviewed-by: NJosh Poimboeuf <jpoimboe@redhat.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Hans Liljestrand <ishkamiel@gmail.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: Jann Horn <jannh@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Serge E. Hallyn <serge@hallyn.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arozansk@redhat.com Cc: axboe@kernel.dk Cc: kernel-hardening@lists.openwall.com Cc: linux-arch <linux-arch@vger.kernel.org> Link: http://lkml.kernel.org/r/20170815161924.GA133115@beastSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 08 8月, 2017 1 次提交
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由 Ard Biesheuvel 提交于
In the Linux kernel, struct type variables are rarely passed by-value, and so functions that initialize such variables typically take an input reference to the variable rather than returning a value that can subsequently be used in an assignment. If the initalization function is not part of the same compilation unit, the lack of an assignment operation defeats any analysis the compiler can perform as to whether the variable may be used before having been initialized. This means we may end up passing on such variables uninitialized, resulting in potential information leaks. So extend the existing structleak GCC plugin so it will [optionally] apply to all struct type variables that have their address taken at any point, rather than only to variables of struct types that have a __user annotation. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: NKees Cook <keescook@chromium.org>
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- 02 8月, 2017 1 次提交
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由 Kees Cook 提交于
This enables the automatic structure selection logic in the randstruct GCC plugin. The selection logic randomizes all structures that contain only function pointers, unless marked with __no_randomize_layout. Signed-off-by: NKees Cook <keescook@chromium.org>
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- 13 7月, 2017 2 次提交
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由 Daniel Micay 提交于
This adds support for compiling with a rough equivalent to the glibc _FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer overflow checks for string.h functions when the compiler determines the size of the source or destination buffer at compile-time. Unlike glibc, it covers buffer reads in addition to writes. GNU C __builtin_*_chk intrinsics are avoided because they would force a much more complex implementation. They aren't designed to detect read overflows and offer no real benefit when using an implementation based on inline checks. Inline checks don't add up to much code size and allow full use of the regular string intrinsics while avoiding the need for a bunch of _chk functions and per-arch assembly to avoid wrapper overhead. This detects various overflows at compile-time in various drivers and some non-x86 core kernel code. There will likely be issues caught in regular use at runtime too. Future improvements left out of initial implementation for simplicity, as it's all quite optional and can be done incrementally: * Some of the fortified string functions (strncpy, strcat), don't yet place a limit on reads from the source based on __builtin_object_size of the source buffer. * Extending coverage to more string functions like strlcat. * It should be possible to optionally use __builtin_object_size(x, 1) for some functions (C strings) to detect intra-object overflows (like glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative approach to avoid likely compatibility issues. * The compile-time checks should be made available via a separate config option which can be enabled by default (or always enabled) once enough time has passed to get the issues it catches fixed. Kees said: "This is great to have. While it was out-of-tree code, it would have blocked at least CVE-2016-3858 from being exploitable (improper size argument to strlcpy()). I've sent a number of fixes for out-of-bounds-reads that this detected upstream already" [arnd@arndb.de: x86: fix fortified memcpy] Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de [keescook@chromium.org: avoid panic() in favor of BUG()] Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast [keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help] Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.orgSigned-off-by: NDaniel Micay <danielmicay@gmail.com> Signed-off-by: NKees Cook <keescook@chromium.org> Signed-off-by: NArnd Bergmann <arnd@arndb.de> Acked-by: NKees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Daniel Axtens <dja@axtens.net> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Nicholas Piggin 提交于
Split SOFTLOCKUP_DETECTOR from LOCKUP_DETECTOR, and split HARDLOCKUP_DETECTOR_PERF from HARDLOCKUP_DETECTOR. LOCKUP_DETECTOR implies the general boot, sysctl, and programming interfaces for the lockup detectors. An architecture that wants to use a hard lockup detector must define HAVE_HARDLOCKUP_DETECTOR_PERF or HAVE_HARDLOCKUP_DETECTOR_ARCH. Alternatively an arch can define HAVE_NMI_WATCHDOG, which provides the minimum arch_touch_nmi_watchdog, and it otherwise does its own thing and does not implement the LOCKUP_DETECTOR interfaces. sparc is unusual in that it has started to implement some of the interfaces, but not fully yet. It should probably be converted to a full HAVE_HARDLOCKUP_DETECTOR_ARCH. [npiggin@gmail.com: fix] Link: http://lkml.kernel.org/r/20170617223522.66c0ad88@roar.ozlabs.ibm.com Link: http://lkml.kernel.org/r/20170616065715.18390-4-npiggin@gmail.comSigned-off-by: NNicholas Piggin <npiggin@gmail.com> Reviewed-by: NDon Zickus <dzickus@redhat.com> Reviewed-by: NBabu Moger <babu.moger@oracle.com> Tested-by: Babu Moger <babu.moger@oracle.com> [sparc] Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 30 6月, 2017 1 次提交
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由 Nicholas Piggin 提交于
Make thin archives build the default, but keep the config option to allow exemptions if any breakage can't be quickly solved. Signed-off-by: NNicholas Piggin <npiggin@gmail.com> Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
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- 29 6月, 2017 1 次提交
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由 Kees Cook 提交于
Many subsystems will not use refcount_t unless there is a way to build the kernel so that there is no regression in speed compared to atomic_t. This adds CONFIG_REFCOUNT_FULL to enable the full refcount_t implementation which has the validation but is slightly slower. When not enabled, refcount_t uses the basic unchecked atomic_t routines, which results in no code changes compared to just using atomic_t directly. Signed-off-by: NKees Cook <keescook@chromium.org> Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: David Windsor <dwindsor@gmail.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Hans Liljestrand <ishkamiel@gmail.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: Jann Horn <jannh@google.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Serge E. Hallyn <serge@hallyn.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arozansk@redhat.com Cc: axboe@kernel.dk Cc: linux-arch <linux-arch@vger.kernel.org> Link: http://lkml.kernel.org/r/20170621200026.GA115679@beastSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 23 6月, 2017 1 次提交
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由 Kees Cook 提交于
This randstruct plugin is modified from Brad Spengler/PaX Team's code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. The randstruct GCC plugin randomizes the layout of selected structures at compile time, as a probabilistic defense against attacks that need to know the layout of structures within the kernel. This is most useful for "in-house" kernel builds where neither the randomization seed nor other build artifacts are made available to an attacker. While less useful for distribution kernels (where the randomization seed must be exposed for third party kernel module builds), it still has some value there since now all kernel builds would need to be tracked by an attacker. In more performance sensitive scenarios, GCC_PLUGIN_RANDSTRUCT_PERFORMANCE can be selected to make a best effort to restrict randomization to cacheline-sized groups of elements, and will not randomize bitfields. This comes at the cost of reduced randomization. Two annotations are defined,__randomize_layout and __no_randomize_layout, which respectively tell the plugin to either randomize or not to randomize instances of the struct in question. Follow-on patches enable the auto-detection logic for selecting structures for randomization that contain only function pointers. It is disabled here to assist with bisection. Since any randomized structs must be initialized using designated initializers, __randomize_layout includes the __designated_init annotation even when the plugin is disabled so that all builds will require the needed initialization. (With the plugin enabled, annotations for automatically chosen structures are marked as well.) The main differences between this implemenation and grsecurity are: - disable automatic struct selection (to be enabled in follow-up patch) - add designated_init attribute at runtime and for manual marking - clarify debugging output to differentiate bad cast warnings - add whitelisting infrastructure - support gcc 7's DECL_ALIGN and DECL_MODE changes (Laura Abbott) - raise minimum required GCC version to 4.7 Earlier versions of this patch series were ported by Michael Leibowitz. Signed-off-by: NKees Cook <keescook@chromium.org>
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- 20 6月, 2017 1 次提交
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由 Jean Delvare 提交于
Signed-off-by: NJean Delvare <jdelvare@suse.de> Fixes: c61f13ea ("gcc-plugins: Add structleak for more stack initialization") Cc: Kees Cook <keescook@chromium.org> Signed-off-by: NKees Cook <keescook@chromium.org>
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- 09 5月, 2017 1 次提交
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由 Hari Bathini 提交于
Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and reuse crashkernel parameter for fadump", v4. Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. This patchset removes dependency with CONFIG_KEXEC for crashkernel parameter and vmcoreinfo related code as it can be reused without kexec support. Also, crashkernel parameter is reused instead of fadump_reserve_mem to reserve memory for fadump. The first patch moves crashkernel parameter parsing and vmcoreinfo related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE. The second patch reuses the definitions of append_elf_note() & final_note() functions under CONFIG_CRASH_CORE in IA64 arch code. The third patch removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump) in powerpc. The next patch reuses crashkernel parameter for reserving memory for fadump, instead of the fadump_reserve_mem parameter. This has the advantage of using all syntaxes crashkernel parameter supports, for fadump as well. The last patch updates fadump kernel documentation about use of crashkernel parameter. This patch (of 5): Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. But currently, code related to vmcoreinfo and parsing of crashkernel parameter is built under CONFIG_KEXEC_CORE. This patch introduces CONFIG_CRASH_CORE and moves the above mentioned code under this config, allowing code reuse without dependency on CONFIG_KEXEC. There is no functional change with this patch. Link: http://lkml.kernel.org/r/149035338104.6881.4550894432615189948.stgit@hbathini.in.ibm.comSigned-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: NDave Young <dyoung@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 27 4月, 2017 1 次提交
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由 Al Viro 提交于
all architectures converted Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 19 4月, 2017 1 次提交
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由 Paul E. McKenney 提交于
The definition of smp_mb__after_unlock_lock() is currently smp_mb() for CONFIG_PPC and a no-op otherwise. It would be better to instead provide an architecture-selectable Kconfig option, and select the strength of smp_mb__after_unlock_lock() based on that option. This commit therefore creates ARCH_WEAK_RELEASE_ACQUIRE, has PPC select it, and bases the definition of smp_mb__after_unlock_lock() on this new ARCH_WEAK_RELEASE_ACQUIRE Kconfig option. Reported-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Boqun Feng <boqun.feng@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Acked-by: NMichael Ellerman <mpe@ellerman.id.au> Cc: <linuxppc-dev@lists.ozlabs.org> Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
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- 29 3月, 2017 1 次提交
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由 Al Viro 提交于
provide raw_copy_..._user() and select ARCH_HAS_RAW_COPY_USER to use those. Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 13 3月, 2017 1 次提交
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由 Dmitry Safonov 提交于
mmap() uses a base address, from which it starts to look for a free space for allocation. The base address is stored in mm->mmap_base, which is calculated during exec(). The address depends on task's size, set rlimit for stack, ASLR randomization. The base depends on the task size and the number of random bits which are different for 64-bit and 32bit applications. Due to the fact, that the base address is fixed, its mmap() from a compat (32bit) syscall issued by a 64bit task will return a address which is based on the 64bit base address and does not fit into the 32bit address space (4GB). The returned pointer is truncated to 32bit, which results in an invalid address. To solve store a seperate compat address base plus a compat legacy address base in mm_struct. These bases are calculated at exec() time and can be used later to address the 32bit compat mmap() issued by 64 bit applications. As a consequence of this change 32-bit applications issuing a 64-bit syscall (after doing a long jump) will get a 64-bit mapping now. Before this change 32-bit applications always got a 32bit mapping. [ tglx: Massaged changelog and added a comment ] Signed-off-by: NDmitry Safonov <dsafonov@virtuozzo.com> Cc: 0x7f454c46@gmail.com Cc: linux-mm@kvack.org Cc: Andy Lutomirski <luto@kernel.org> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Borislav Petkov <bp@suse.de> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: http://lkml.kernel.org/r/20170306141721.9188-4-dsafonov@virtuozzo.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 08 3月, 2017 1 次提交
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由 Josh Poimboeuf 提交于
For live patching and possibly other use cases, a stack trace is only useful if it can be assured that it's completely reliable. Add a new save_stack_trace_tsk_reliable() function to achieve that. Note that if the target task isn't the current task, and the target task is allowed to run, then it could be writing the stack while the unwinder is reading it, resulting in possible corruption. So the caller of save_stack_trace_tsk_reliable() must ensure that the task is either 'current' or inactive. save_stack_trace_tsk_reliable() relies on the x86 unwinder's detection of pt_regs on the stack. If the pt_regs are not user-mode registers from a syscall, then they indicate an in-kernel interrupt or exception (e.g. preemption or a page fault), in which case the stack is considered unreliable due to the nature of frame pointers. It also relies on the x86 unwinder's detection of other issues, such as: - corrupted stack data - stack grows the wrong way - stack walk doesn't reach the bottom - user didn't provide a large enough entries array Such issues are reported by checking unwind_error() and !unwind_done(). Also add CONFIG_HAVE_RELIABLE_STACKTRACE so arch-independent code can determine at build time whether the function is implemented. Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: NMiroslav Benes <mbenes@suse.cz> Acked-by: Ingo Molnar <mingo@kernel.org> # for the x86 changes Signed-off-by: NJiri Kosina <jkosina@suse.cz>
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- 28 2月, 2017 1 次提交
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由 Masahiro Yamada 提交于
Fix typos and add the following to the scripts/spelling.txt: an user||a user an userspace||a userspace I also added "userspace" to the list since it is a common word in Linux. I found some instances for "an userfaultfd", but I did not add it to the list. I felt it is endless to find words that start with "user" such as "userland" etc., so must draw a line somewhere. Link: http://lkml.kernel.org/r/1481573103-11329-4-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 25 2月, 2017 1 次提交
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由 Matthew Wilcox 提交于
The current transparent hugepage code only supports PMDs. This patch adds support for transparent use of PUDs with DAX. It does not include support for anonymous pages. x86 support code also added. Most of this patch simply parallels the work that was done for huge PMDs. The only major difference is how the new ->pud_entry method in mm_walk works. The ->pmd_entry method replaces the ->pte_entry method, whereas the ->pud_entry method works along with either ->pmd_entry or ->pte_entry. The pagewalk code takes care of locking the PUD before calling ->pud_walk, so handlers do not need to worry whether the PUD is stable. [dave.jiang@intel.com: fix SMP x86 32bit build for native_pud_clear()] Link: http://lkml.kernel.org/r/148719066814.31111.3239231168815337012.stgit@djiang5-desk3.ch.intel.com [dave.jiang@intel.com: native_pud_clear missing on i386 build] Link: http://lkml.kernel.org/r/148640375195.69754.3315433724330910314.stgit@djiang5-desk3.ch.intel.com Link: http://lkml.kernel.org/r/148545059381.17912.8602162635537598445.stgit@djiang5-desk3.ch.intel.comSigned-off-by: NMatthew Wilcox <mawilcox@microsoft.com> Signed-off-by: NDave Jiang <dave.jiang@intel.com> Tested-by: NAlexander Kapshuk <alexander.kapshuk@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Jan Kara <jack@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 22 2月, 2017 1 次提交
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由 Daniel Borkmann 提交于
Currently, there's no good way to test for the presence of set_memory_ro/rw/x/nx() helpers implemented by archs such as x86, arm, arm64 and s390. There's DEBUG_SET_MODULE_RONX and DEBUG_RODATA, however both don't really reflect that: set_memory_*() are also available even when DEBUG_SET_MODULE_RONX is turned off, and DEBUG_RODATA is set by parisc, but doesn't implement above functions. Thus, add ARCH_HAS_SET_MEMORY that is selected by mentioned archs, where generic code can test against this. This also allows later on to move DEBUG_SET_MODULE_RONX out of the arch specific Kconfig to define it only once depending on ARCH_HAS_SET_MEMORY. Suggested-by: NLaura Abbott <labbott@redhat.com> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 2月, 2017 2 次提交
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由 Laura Abbott 提交于
Both of these options are poorly named. The features they provide are necessary for system security and should not be considered debug only. Change the names to CONFIG_STRICT_KERNEL_RWX and CONFIG_STRICT_MODULE_RWX to better describe what these options do. Signed-off-by: NLaura Abbott <labbott@redhat.com> Acked-by: NJessica Yu <jeyu@redhat.com> Signed-off-by: NKees Cook <keescook@chromium.org>
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由 Laura Abbott 提交于
There are multiple architectures that support CONFIG_DEBUG_RODATA and CONFIG_SET_MODULE_RONX. These options also now have the ability to be turned off at runtime. Move these to an architecture independent location and make these options def_bool y for almost all of those arches. Signed-off-by: NLaura Abbott <labbott@redhat.com> Acked-by: NIngo Molnar <mingo@kernel.org> Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: NKees Cook <keescook@chromium.org>
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- 19 1月, 2017 2 次提交
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由 Mao Wenan 提交于
Relax ordering(RO) is one feature of 82599 NIC, to enable this feature can enhance the performance for some cpu architecure, such as SPARC and so on. Currently it only supports one special cpu architecture(SPARC) in 82599 driver to enable RO feature, this is not very common for other cpu architecture which really needs RO feature. This patch add one common config CONFIG_ARCH_WANT_RELAX_ORDER to set RO feature, and should define CONFIG_ARCH_WANT_RELAX_ORDER in sparc Kconfig firstly. Signed-off-by: NMao Wenan <maowenan@huawei.com> Reviewed-by: NAlexander Duyck <alexander.duyck@gmail.com> Reviewed-by: NAlexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Kees Cook 提交于
This plugin detects any structures that contain __user attributes and makes sure it is being fully initialized so that a specific class of information exposure is eliminated. (This plugin was originally designed to block the exposure of siginfo in CVE-2013-2141.) Ported from grsecurity/PaX. This version adds a verbose option to the plugin and the Kconfig. Signed-off-by: NKees Cook <keescook@chromium.org>
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