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2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09arm/asm: add loglvl to c_backtrace()Dmitry Safonov
Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Add log level argument to c_backtrace() as a preparation for introducing show_stack_loglvl(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200418201944.482088-5-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04arm: add support for folded p4d page tablesMike Rapoport
Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate, and remove __ARCH_USE_5LEVEL_HACK. [rppt@linux.ibm.com: fix kexec] Link: http://lkml.kernel.org/r/20200508174232.GA759899@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: James Morse <james.morse@arm.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Julien Thierry <julien.thierry.kdev@gmail.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200414153455.21744-3-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-21ARM: 8958/1: rename missed uaccess .fixup sectionKees Cook
When the uaccess .fixup section was renamed to .text.fixup, one case was missed. Under ld.bfd, the orphaned section was moved close to .text (since they share the "ax" bits), so things would work normally on uaccess faults. Under ld.lld, the orphaned section was placed outside the .text section, making it unreachable. Link: https://github.com/ClangBuiltLinux/linux/issues/282 Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1020633#c44 Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.1912032147340.17114@knanqh.ubzr Link: https://lore.kernel.org/lkml/202002071754.F5F073F1D@keescook/ Fixes: c4a84ae39b4a5 ("ARM: 8322/1: keep .text and .fixup regions closer together") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-09-22Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: - fix various clang build and cppcheck issues - switch ARM to use new common outgoing-CPU-notification code - add some additional explanation about the boot code - kbuild "make clean" fixes - get rid of another "(____ptrval____)", this time for the VDSO code - avoid treating cache maintenance faults as a write - add a frame pointer unwinder implementation for clang - add EDAC support for Aurora L2 cache - improve robustness of adjust_lowmem_bounds() finding the bounds of lowmem. - add reset control for AMBA primecell devices * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (24 commits) ARM: 8906/1: drivers/amba: add reset control to amba bus probe ARM: 8905/1: Emit __gnu_mcount_nc when using Clang 10.0.0 or newer ARM: 8904/1: skip nomap memblocks while finding the lowmem/highmem boundary ARM: 8903/1: ensure that usable memory in bank 0 starts from a PMD-aligned address ARM: 8891/1: EDAC: armada_xp: Add support for more SoCs ARM: 8888/1: EDAC: Add driver for the Marvell Armada XP SDRAM and L2 cache ECC ARM: 8892/1: EDAC: Add missing debugfs_create_x32 wrapper ARM: 8890/1: l2x0: add marvell,ecc-enable property for aurora ARM: 8889/1: dt-bindings: document marvell,ecc-enable binding ARM: 8886/1: l2x0: support parity-enable/disable on aurora ARM: 8885/1: aurora-l2: add defines for parity and ECC registers ARM: 8887/1: aurora-l2: add prefix to MAX_RANGE_SIZE ARM: 8902/1: l2c: move cache-aurora-l2.h to asm/hardware ARM: 8900/1: UNWINDER_FRAME_POINTER implementation for Clang ARM: 8898/1: mm: Don't treat faults reported from cache maintenance as writes ARM: 8896/1: VDSO: Don't leak kernel addresses ARM: 8895/1: visit mach-* and plat-* directories when cleaning ARM: 8894/1: boot: Replace open-coded nop with macro ARM: 8893/1: boot: Explain the 8 nops ARM: 8876/1: fix O= building with CONFIG_FPE_FASTFPE ...
2019-08-29ARM: 8900/1: UNWINDER_FRAME_POINTER implementation for ClangNathan Huckleberry
The stackframe setup when compiled with clang is different. Since the stack unwinder expects the gcc stackframe setup it fails to print backtraces. This patch adds support for the clang stackframe setup. Link: https://github.com/ClangBuiltLinux/linux/issues/35 Cc: clang-built-linux@googlegroups.com Suggested-by: Tri Vo <trong@google.com> Signed-off-by: Nathan Huckleberry <nhuck@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-08-23ARM: 8897/1: check stmfd instruction using right shiftLvqiang Huang
In the commit ef41b5c92498 ("ARM: make kernel oops easier to read"), - .word 0xe92d0000 >> 10 @ stmfd sp!, {} + .word 0xe92d0000 >> 11 @ stmfd sp!, {} then the shift need to change to 11. Signed-off-by: Lvqiang Huang <Lvqiang.Huang@unisoc.com> Signed-off-by: Chunyan Zhang <zhang.lyra@gmail.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-07-19Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/socLinus Torvalds
Pull ARM SoC platform updates from Olof Johansson: "SoC platform changes. Main theme this merge window: - The Netx platform (Netx 100/500) platform is removed by Linus Walleij-- the SoC doesn't have active maintainers with hardware, and in discussions with the vendor the agreement was that it's OK to remove. - Russell King has a series of patches that cleans up and refactors SA1101 and RiscPC support" * tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (47 commits) ARM: stm32: use "depends on" instead of "if" after prompt ARM: sa1100: convert to common clock framework ARM: exynos: Cleanup cppcheck shifting warning ARM: pxa/lubbock: remove lubbock_set_misc_wr() from global view ARM: exynos: Only build MCPM support if used arm: add missing include platform-data/atmel.h ARM: davinci: Use GPIO lookup table for DA850 LEDs ARM: OMAP2: drop explicit assembler architecture ARM: use arch_extension directive instead of arch argument ARM: imx: Switch imx7d to imx-cpufreq-dt for speed-grading ARM: bcm: Enable PINCTRL for ARCH_BRCMSTB ARM: bcm: Enable ARCH_HAS_RESET_CONTROLLER for ARCH_BRCMSTB ARM: riscpc: enable chained scatterlist support ARM: riscpc: reduce IRQ handling code ARM: riscpc: move RiscPC assembly files from arch/arm/lib to mach-rpc ARM: riscpc: parse video information from tagged list ARM: riscpc: add ecard quirk for Atomwide 3port serial card MAINTAINERS: mvebu: Add git entry soc: ti: pm33xx: Add a print while entering RTC only mode with DDR in self-refresh ARM: OMAP2+: Make some variables static ...
2019-07-15Merge branch 'for-arm-soc' of git://git.armlinux.org.uk/~rmk/linux-arm into ↵Olof Johansson
arm/soc * 'for-arm-soc' of git://git.armlinux.org.uk/~rmk/linux-arm: (21 commits) ARM: sa1100: convert to common clock framework ARM: riscpc: enable chained scatterlist support ARM: riscpc: reduce IRQ handling code ARM: riscpc: move RiscPC assembly files from arch/arm/lib to mach-rpc ARM: riscpc: parse video information from tagged list ARM: riscpc: add ecard quirk for Atomwide 3port serial card ARM: sa1100/neponset: convert serial to use gpiod APIs ARM: sa1100/hackkit: remove empty serial mctrl functions ARM: sa1100/badge4: remove commented out modem control initialisers ARM: sa1100/h3xxx: convert serial to gpiod APIs ARM: sa1100/assabet: convert serial to gpiod APIs serial: sa1100: add note about modem control signals serial: sa1100: add support for mctrl gpios ARM: riscpc: dma: use __iomem pointers for writing DMA ARM: riscpc: dma: improve address/length writing ARM: riscpc: dma: make state a local variable ARM: riscpc: dma: eliminate "cur_sg" scatterlist usage ARM: riscpc: fix DMA ARM: riscpc: fix ecard printing ARM: riscpc: fix lack of keyboard interrupts after irq conversion ... Signed-off-by: Olof Johansson <olof@lixom.net>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11ARM: riscpc: move RiscPC assembly files from arch/arm/lib to mach-rpcRussell King
Move the assembly files for RiscPC from arch/arm/lib to mach-rpc so that we contain RiscPC bits in one subdirectory. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-26ARM: 8844/1: use unified assembler in assembly filesStefan Agner
Use unified assembler syntax (UAL) in assembly files. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-26ARM: 8843/1: use unified assembler in headersStefan Agner
Use unified assembler syntax (UAL) in headers. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-26ARM: 8841/1: use unified assembler in macrosStefan Agner
Use unified assembler syntax (UAL) in macros. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-12ARM: 8833/1: Ensure that NEON code always compiles with ClangNathan Chancellor
While building arm32 allyesconfig, I ran into the following errors: arch/arm/lib/xor-neon.c:17:2: error: You should compile this file with '-mfloat-abi=softfp -mfpu=neon' In file included from lib/raid6/neon1.c:27: /home/nathan/cbl/prebuilt/lib/clang/8.0.0/include/arm_neon.h:28:2: error: "NEON support not enabled" Building V=1 showed NEON_FLAGS getting passed along to Clang but __ARM_NEON__ was not getting defined. Ultimately, it boils down to Clang only defining __ARM_NEON__ when targeting armv7, rather than armv6k, which is the '-march' value for allyesconfig. >From lib/Basic/Targets/ARM.cpp in the Clang source: // This only gets set when Neon instructions are actually available, unlike // the VFP define, hence the soft float and arch check. This is subtly // different from gcc, we follow the intent which was that it should be set // when Neon instructions are actually available. if ((FPU & NeonFPU) && !SoftFloat && ArchVersion >= 7) { Builder.defineMacro("__ARM_NEON", "1"); Builder.defineMacro("__ARM_NEON__"); // current AArch32 NEON implementations do not support double-precision // floating-point even when it is present in VFP. Builder.defineMacro("__ARM_NEON_FP", "0x" + Twine::utohexstr(HW_FP & ~HW_FP_DP)); } Ard Biesheuvel recommended explicitly adding '-march=armv7-a' at the beginning of the NEON_FLAGS definitions so that __ARM_NEON__ always gets definined by Clang. This doesn't functionally change anything because that code will only run where NEON is supported, which is implicitly armv7. Link: https://github.com/ClangBuiltLinux/linux/issues/287 Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-01ARM: 8827/1: fix argument count to match macro definitionStefan Agner
The macro str8w takes 10 arguments, abort being the 10th. In this particular instantiation the abort argument is passed as 11th argument leading to an error when using LLVM's integrated assembler: <instantiation>:46:47: error: too many positional arguments str8w r0, r3, r4, r5, r6, r7, r8, r9, ip, , abort=19f ^ arch/arm/lib/copy_template.S:277:5: note: while in macro instantiation 18: forward_copy_shift pull=24 push=8 ^ The argument is not used in the macro hence this does not change code generation. Signed-off-by: Stefan Agner <stefan@agner.ch> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-12ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+Vincent Whitchurch
getuser() and putuser() (and there underscored variants) use two strb[t]/ldrb[t] instructions when they are asked to get/put 16-bits. This means that the read/write is not atomic even when performed to a 16-bit-aligned address. This leads to problems with vhost: vhost uses __getuser() to read the vring's 16-bit avail.index field, and if it happens to observe a partial update of the index, wrong descriptors will be used which will lead to a breakdown of the virtio communication. A similar problem exists for __putuser() which is used to write to the vring's used.index field. The reason these functions use strb[t]/ldrb[t] is because strht/ldrht instructions did not exist until ARMv6T2/ARMv7. So we should be easily able to fix this on ARMv7. Also, since all ARMv6 processors also don't actually use the unprivileged instructions anymore for uaccess (since CONFIG_CPU_USE_DOMAINS is not used) we can easily fix them too. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-12ARM: 8812/1: Optimise copy_{from/to}_user for !CPU_USE_DOMAINSVincent Whitchurch
ARMv6+ processors do not use CONFIG_CPU_USE_DOMAINS and use privileged ldr/str instructions in copy_{from/to}_user. They are currently unnecessarily using single ldr/str instructions and can use ldm/stm instructions instead like memcpy does (but with appropriate fixup tables). This speeds up a "dd if=foo of=bar bs=32k" on a tmpfs filesystem by about 4% on my Cortex-A9. before:134217728 bytes (128.0MB) copied, 0.543848 seconds, 235.4MB/s before:134217728 bytes (128.0MB) copied, 0.538610 seconds, 237.6MB/s before:134217728 bytes (128.0MB) copied, 0.544356 seconds, 235.1MB/s before:134217728 bytes (128.0MB) copied, 0.544364 seconds, 235.1MB/s before:134217728 bytes (128.0MB) copied, 0.537130 seconds, 238.3MB/s before:134217728 bytes (128.0MB) copied, 0.533443 seconds, 240.0MB/s before:134217728 bytes (128.0MB) copied, 0.545691 seconds, 234.6MB/s before:134217728 bytes (128.0MB) copied, 0.534695 seconds, 239.4MB/s before:134217728 bytes (128.0MB) copied, 0.540561 seconds, 236.8MB/s before:134217728 bytes (128.0MB) copied, 0.541025 seconds, 236.6MB/s after:134217728 bytes (128.0MB) copied, 0.520445 seconds, 245.9MB/s after:134217728 bytes (128.0MB) copied, 0.527846 seconds, 242.5MB/s after:134217728 bytes (128.0MB) copied, 0.519510 seconds, 246.4MB/s after:134217728 bytes (128.0MB) copied, 0.527231 seconds, 242.8MB/s after:134217728 bytes (128.0MB) copied, 0.525030 seconds, 243.8MB/s after:134217728 bytes (128.0MB) copied, 0.524236 seconds, 244.2MB/s after:134217728 bytes (128.0MB) copied, 0.523659 seconds, 244.4MB/s after:134217728 bytes (128.0MB) copied, 0.525018 seconds, 243.8MB/s after:134217728 bytes (128.0MB) copied, 0.519249 seconds, 246.5MB/s after:134217728 bytes (128.0MB) copied, 0.518527 seconds, 246.9MB/s Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-10Merge branches 'fixes', 'misc' and 'spectre' into for-nextRussell King
2018-10-05ARM: 8797/1: spectre-v1.1: harden __copy_to_userJulien Thierry
Sanitize user pointer given to __copy_to_user, both for standard version and memcopy version of the user accessor. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-05ARM: 8796/1: spectre-v1,v1.1: provide helpers for address sanitizationJulien Thierry
Introduce C and asm helpers to sanitize user address, taking the address range they target into account. Use asm helper for existing sanitization in __copy_from_user(). Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-13Merge branches 'fixes', 'misc' and 'spectre' into for-linusRussell King
Conflicts: arch/arm/include/asm/uaccess.h Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-02ARM: spectre-v1: mitigate user accessesRussell King
Spectre variant 1 attacks are about this sequence of pseudo-code: index = load(user-manipulated pointer); access(base + index * stride); In order for the cache side-channel to work, the access() must me made to memory which userspace can detect whether cache lines have been loaded. On 32-bit ARM, this must be either user accessible memory, or a kernel mapping of that same user accessible memory. The problem occurs when the load() speculatively loads privileged data, and the subsequent access() is made to user accessible memory. Any load() which makes use of a user-maniplated pointer is a potential problem if the data it has loaded is used in a subsequent access. This also applies for the access() if the data loaded by that access is used by a subsequent access. Harden the get_user() accessors against Spectre attacks by forcing out of bounds addresses to a NULL pointer. This prevents get_user() being used as the load() step above. As a side effect, put_user() will also be affected even though it isn't implicated. Also harden copy_from_user() by redoing the bounds check within the arm_copy_from_user() code, and NULLing the pointer if out of bounds. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-05-19ARM: 8772/1: kprobes: Prohibit kprobes on get_user functionsMasami Hiramatsu
Since do_undefinstr() uses get_user to get the undefined instruction, it can be called before kprobes processes recursive check. This can cause an infinit recursive exception. Prohibit probing on get_user functions. Fixes: 24ba613c9d6c ("ARM kprobes: core code") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-01-21Merge branches 'fixes', 'misc', 'sa1111' and 'sa1100-for-next' into for-nextRussell King
2018-01-21ARM: 8745/1: get rid of __memzero()Nicolas Pitre
The __memzero assembly code is almost identical to memset's except for two orr instructions. The runtime performance of __memset(p, n) and memset(p, 0, n) is accordingly almost identical. However, the memset() macro used to guard against a zero length and to call __memzero at compile time when the fill value is a constant zero interferes with compiler optimizations. Arnd found tha the test against a zero length brings up some new warnings with gcc v8: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82103 And successively rremoving the test against a zero length and the call to __memzero optimization produces the following kernel sizes for defconfig with gcc 6: text data bss dec hex filename 12248142 6278960 413588 18940690 1210312 vmlinux.orig 12244474 6278960 413588 18937022 120f4be vmlinux.no_zero_test 12239160 6278960 413588 18931708 120dffc vmlinux.no_memzero So it is probably not worth keeping __memzero around given that the compiler can do a better job at inlining trivial memset(p,0,n) on its own. And the memset code already handles a zero length just fine. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-12-17ARM: 8731/1: Fix csum_partial_copy_from_user() stack mismatchChunyan Zhang
An additional 'ip' will be pushed to the stack, for restoring the DACR later, if CONFIG_CPU_SW_DOMAIN_PAN defined. However, the fixup still get the err_ptr by add #8*4 to sp, which results in the fact that the code area pointed by the LR will be overwritten, or the kernel will crash if CONFIG_DEBUG_RODATA is enabled. This patch fixes the stack mismatch. Fixes: a5e090acbf54 ("ARM: software-based priviledged-no-access support") Signed-off-by: Lvqiang Huang <Lvqiang.Huang@spreadtrum.com> Signed-off-by: Chunyan Zhang <zhang.lyra@gmail.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-08ARM: implement memset32 & memset64Matthew Wilcox
Reuse the existing optimised memset implementation to implement an optimised memset32 and memset64. Link: http://lkml.kernel.org/r/20170720184539.31609-5-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: David Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-28new helper: uaccess_kernel()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-02-16ARM: 8658/1: uaccess: fix zeroing of 64-bit get_user()Kees Cook
The 64-bit get_user() wasn't clearing the high word due to a typo in the error handler. The exception handler entry was already correct, though. Noticed during recent usercopy test additions in lib/test_user_copy.c. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-12-14Merge branches 'clkdev', 'fixes', 'misc' and 'sa1100-base' into for-linusRussell King
2016-11-23Revert "arm: move exports to definitions"Russell King
This reverts commit 4dd1837d7589f468ed109556513f476e7a7f9121. Moving the exports for assembly code into the assembly files breaks KSYM trimming, but also breaks modversions. While fixing the KSYM trimming is trivial, fixing modversions brings us to a technically worse position that we had prior to the above change: - We end up with the prototype definitions divorsed from everything else, which means that adding or removing assembly level ksyms become more fragile: * if adding a new assembly ksyms export, a missed prototype in asm-prototypes.h results in a successful build if no module in the selected configuration makes use of the symbol. * when removing a ksyms export, asm-prototypes.h will get forgotten, with armksyms.c, you'll get a build error if you forget to touch the file. - We end up with the same amount of include files and prototypes, they're just in a header file instead of a .c file with their exports. As for lines of code, we don't get much of a size reduction: (original commit) 47 files changed, 131 insertions(+), 208 deletions(-) (fix for ksyms trimming) 7 files changed, 18 insertions(+), 5 deletions(-) (two fixes for modversions) 1 file changed, 34 insertions(+) 3 files changed, 7 insertions(+), 2 deletions(-) which results in a net total of only 25 lines deleted. As there does not seem to be much benefit from this change of approach, revert the change. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-11-15ARM: fix backtraceRussell King
Recent kernels have changed their behaviour to be more inconsistent when handling printk continuations. With todays kernels, the output looks sane on the console, but dmesg splits individual printk()s which do not have the KERN_CONT prefix into separate lines. Since the assembly code is not trivial to add the KERN_CONT, and we ideally want to avoid using KERN_CONT (as multiple printk()s can race between different threads), convert the assembly dumping the register values to C code, and have the C code build the output a line at a time before dumping to the console. This avoids the KERN_CONT issue, and also avoids situations where the output is intermixed with other console activity. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-10-19ARM: 8619/1: udelay: document the various constantsNicolas Pitre
Explain where the value for UDELAY_MULT and UDELAY_SHIFT come from. Also fix/clarify some comments pertaining to their usage in the assembly code. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-10-14Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more misc uaccess and vfs updates from Al Viro: "The rest of the stuff from -next (more uaccess work) + assorted fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: score: traps: Add missing include file to fix build error fs/super.c: don't fool lockdep in freeze_super() and thaw_super() paths fs/super.c: fix race between freeze_super() and thaw_super() overlayfs: Fix setting IOP_XATTR flag iov_iter: kernel-doc import_iovec() and rw_copy_check_uvector() blackfin: no access_ok() for __copy_{to,from}_user() arm64: don't zero in __copy_from_user{,_inatomic} arm: don't zero in __copy_from_user_inatomic()/__copy_from_user() arc: don't leak bits of kernel stack into coredump alpha: get rid of tail-zeroing in __copy_user()
2016-10-14Merge branch 'work.uaccess' into for-linusAl Viro
2016-10-14Merge branch 'kbuild' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - EXPORT_SYMBOL for asm source by Al Viro. This does bring a regression, because genksyms no longer generates checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is working on a patch to fix this. Plus, we are talking about functions like strcpy(), which rarely change prototypes. - Fixes for PPC fallout of the above by Stephen Rothwell and Nick Piggin - fixdep speedup by Alexey Dobriyan. - preparatory work by Nick Piggin to allow architectures to build with -ffunction-sections, -fdata-sections and --gc-sections - CONFIG_THIN_ARCHIVES support by Stephen Rothwell - fix for filenames with colons in the initramfs source by me. * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits) initramfs: Escape colons in depfile ppc: there is no clear_pages to export powerpc/64: whitelist unresolved modversions CRCs kbuild: -ffunction-sections fix for archs with conflicting sections kbuild: add arch specific post-link Makefile kbuild: allow archs to select link dead code/data elimination kbuild: allow architectures to use thin archives instead of ld -r kbuild: Regenerate genksyms lexer kbuild: genksyms fix for typeof handling fixdep: faster CONFIG_ search ia64: move exports to definitions sparc32: debride memcpy.S a bit [sparc] unify 32bit and 64bit string.h sparc: move exports to definitions ppc: move exports to definitions arm: move exports to definitions s390: move exports to definitions m68k: move exports to definitions alpha: move exports to actual definitions x86: move exports to actual definitions ...
2016-09-15arm: don't zero in __copy_from_user_inatomic()/__copy_from_user()Al Viro
adjust copy_from_user(), obviously Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-08-12ARM: 8595/2: apply more __ro_after_initKees Cook
Guided by grsecurity's analogous __read_only markings in arch/arm, this applies several uses of __ro_after_init to structures that are only updated during __init. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-08-07arm: move exports to definitionsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-22ARM: 8306/1: loop_udelay: remove bogomips value limitationNicolas Pitre
Now that we don't support ARMv3 anymore, the loop based delay code can convert microsecs into number of loops using a 64-bit multiplication and more precision. This allows us to lift the hard limit of 3355 on the bogomips value as loops_per_jiffy may now safely span the full 32-bit range. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-01-15arm, thp: remove infrastructure for handling splitting PMDsKirill A. Shutemov
With new refcounting we don't need to mark PMDs splitting. Let's drop code to handle this. pmdp_splitting_flush() is not needed too: on splitting PMD we will do pmdp_clear_flush() + set_pte_at(). pmdp_clear_flush() will do IPI as needed for fast_gup. [arnd@arndb.de: fix unterminated ifdef in header file] Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-05Merge branches 'misc' and 'misc-rc6' into for-linusRussell King
2015-12-17ARM: 8477/1: runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()Nicolas Pitre
The ARM compiler inserts calls to __aeabi_idiv() and __aeabi_uidiv() when it needs to perform division on signed and unsigned integers. If a processor has support for the sdiv and udiv instructions, the kernel may overwrite the beginning of those functions with those instructions and a "bx lr" to get better performance. To ensure that those functions are aligned to a 32-bit word for easier patching (which might not always be the case in Thumb mode) and that the two patched instructions end up in the same cache line, a 8-byte alignment is enforced when ARM_PATCH_IDIV is selected. This was heavily inspired by a previous patch from Stephen Boyd. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-12-15ARM: fix uaccess_with_memcpy() with SW_DOMAIN_PANRussell King
The uaccess_with_memcpy() code is currently incompatible with the SW PAN code: it takes locks within the region that we've changed the DACR, potentially sleeping as a result. As we do not save and restore the DACR across co-operative sleep events, can lead to an incorrect DACR value later in this code path. Reported-by: Peter Rosin <peda@axentia.se> Tested-by: Peter Rosin <peda@axentia.se> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-10-03ARM: 8438/1: Add unwinding to __clear_user_std()Stephen Boyd
Add unwinding annotations so that unwinding from this function works properly. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-09-03Merge branches 'cleanup', 'fixes', 'misc', 'omap-barrier' and 'uaccess' into ↵Russell King
for-linus
2015-08-26ARM: software-based priviledged-no-access supportRussell King
Provide a software-based implementation of the priviledged no access support found in ARMv8.1. Userspace pages are mapped using a different domain number from the kernel and IO mappings. If we switch the user domain to "no access" when we enter the kernel, we can prevent the kernel from touching userspace. However, the kernel needs to be able to access userspace via the various user accessor functions. With the wrapping in the previous patch, we can temporarily enable access when the kernel needs user access, and re-disable it afterwards. This allows us to trap non-intended accesses to userspace, eg, caused by an inadvertent dereference of the LIST_POISON* values, which, with appropriate user mappings setup, can be made to succeed. This in turn can allow use-after-free bugs to be further exploited than would otherwise be possible. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>