aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/traps.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2020-06-18maccess: make get_kernel_nofault() check for minimal type compatibilityLinus Torvalds1-1/+1
Now that we've renamed probe_kernel_address() to get_kernel_nofault() and made it look and behave more in line with get_user(), some of the subtle type behavior differences end up being more obvious and possibly dangerous. When you do get_user(val, user_ptr); the type of the access comes from the "user_ptr" part, and the above basically acts as val = *user_ptr; by design (except, of course, for the fact that the actual dereference is done with a user access). Note how in the above case, the type of the end result comes from the pointer argument, and then the value is cast to the type of 'val' as part of the assignment. So the type of the pointer is ultimately the more important type both for the access itself. But 'get_kernel_nofault()' may now _look_ similar, but it behaves very differently. When you do get_kernel_nofault(val, kernel_ptr); it behaves like val = *(typeof(val) *)kernel_ptr; except, of course, for the fact that the actual dereference is done with exception handling so that a faulting access is suppressed and returned as the error code. But note how different the casting behavior of the two superficially similar accesses are: one does the actual access in the size of the type the pointer points to, while the other does the access in the size of the target, and ignores the pointer type entirely. Actually changing get_kernel_nofault() to act like get_user() is almost certainly the right thing to do eventually, but in the meantime this patch adds logit to at least verify that the pointer type is compatible with the type of the result. In many cases, this involves just casting the pointer to 'void *' to make it obvious that the type of the pointer is not the important part. It's not how 'get_user()' acts, but at least the behavioral difference is now obvious and explicit. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-18maccess: rename probe_kernel_address to get_kernel_nofaultChristoph Hellwig1-1/+1
Better describe what this helper does, and match the naming of copy_from_kernel_nofault. Also switch the argument order around, so that it acts and looks like get_user(). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09kernel: rename show_stack_loglvl() => show_stack()Dmitry Safonov1-7/+1
Now the last users of show_stack() got converted to use an explicit log level, show_stack_loglvl() can drop it's redundant suffix and become once again well known show_stack(). Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09arm: add show_stack_loglvl()Dmitry Safonov1-2/+8
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. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). [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/20200418201944.482088-9-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09arm: wire up dump_backtrace_{entry,stm}Dmitry Safonov1-5/+7
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. Now that c_backtrace() always emits correct loglvl, use it for printing. [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/20200418201944.482088-8-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09arm: add loglvl to dump_backtrace()Dmitry Safonov1-7/+9
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 dump_backtrace() as a preparation for introducing show_stack_loglvl(). As a good side-effect __die() now prints not only "Stack:" header with KERN_EMERG, but the backtrace itself. [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/20200418201944.482088-7-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09arm: add loglvl to unwind_backtrace()Dmitry Safonov1-3/+3
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 unwind_backtrace() as a preparation for introducing show_stack_loglvl(). As a good side-effect arm_syscall() is now printing errors with the same log level as the backtrace. [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/20200418201944.482088-6-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09arm/asm: add loglvl to c_backtrace()Dmitry Safonov1-4/+5
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>
2020-06-08arm: rename flush_cache_user_range to flush_icache_user_rangeChristoph Hellwig1-1/+1
flush_icache_user_range will be the name for a generic primitive. Move the arm name so that arm already has an implementation. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Russell King <linux@armlinux.org.uk> Link: http://lkml.kernel.org/r/20200515143646.3857579-24-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds1-2/+4
Pull ARM updates from Russell King: - decompressor updates - prevention of out-of-bounds access while stacktracing - fix a section mismatch warning with free_memmap() - make kexec depend on MMU to avoid some build errors - remove swapops stubs * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8954/1: NOMMU: remove stubs for swapops ARM: 8952/1: Disable kmemleak on XIP kernels ARM: 8951/1: Fix Kexec compilation issue. ARM: 8949/1: mm: mark free_memmap as __init ARM: 8948/1: Prevent OOB access in stacktrace ARM: 8945/1: decompressor: use CONFIG option instead of cc-option ARM: 8942/1: Revert "8857/1: efi: enable CP15 DMB instructions before cleaning the cache" ARM: 8941/1: decompressor: enable CP15 barrier instructions in v7 cache setup code
2020-01-25ARM: 8948/1: Prevent OOB access in stacktraceVincent Whitchurch1-2/+4
The stacktrace code can read beyond the stack size, when it attempts to read pt_regs from exception frames. This can happen on normal, non-corrupt stacks. Since the unwind information in the extable is not correct for function prologues, the unwinding code can return data from the stack which is not actually the caller function address, and if in_entry_text() happens to succeed on this value, we can end up reading data from outside the task's stack when attempting to read pt_regs, since there is no bounds check. Example: [<8010e729>] (unwind_backtrace) from [<8010a9c9>] (show_stack+0x11/0x14) [<8010a9c9>] (show_stack) from [<8057d8d7>] (dump_stack+0x87/0xac) [<8057d8d7>] (dump_stack) from [<8012271d>] (tasklet_action_common.constprop.4+0xa5/0xa8) [<8012271d>] (tasklet_action_common.constprop.4) from [<80102333>] (__do_softirq+0x11b/0x31c) [<80102333>] (__do_softirq) from [<80122485>] (irq_exit+0xad/0xd8) [<80122485>] (irq_exit) from [<8015f3d7>] (__handle_domain_irq+0x47/0x84) [<8015f3d7>] (__handle_domain_irq) from [<8036a523>] (gic_handle_irq+0x43/0x78) [<8036a523>] (gic_handle_irq) from [<80101a49>] (__irq_svc+0x69/0xb4) Exception stack(0xeb491f58 to 0xeb491fa0) 1f40: 7eb14794 00000000 1f60: ffffffff 008dd32c 008dd324 ffffffff 008dd314 0000002a 801011e4 eb490000 1f80: 0000002a 7eb1478c 50c5387d eb491fa8 80101001 8023d09c 40080033 ffffffff [<80101a49>] (__irq_svc) from [<8023d09c>] (do_pipe2+0x0/0xac) [<8023d09c>] (do_pipe2) from [<ffffffff>] (0xffffffff) Exception stack(0xeb491fc8 to 0xeb492010) 1fc0: 008dd314 0000002a 00511ad8 008de4c8 7eb14790 7eb1478c 1fe0: 00511e34 7eb14774 004c8557 76f44098 60080030 7eb14794 00000000 00000000 2000: 00000001 00000000 ea846c00 ea847cc0 In this example, the stack limit is 0xeb492000, but 16 bytes outside the stack have been read. Fix it by adding bounds checks. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-12-08sched/rt, ARM: Use CONFIG_PREEMPTIONThomas Gleixner1-0/+2
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the entry code, cache over to use CONFIG_PREEMPTION and add output in show_stack() for PREEMPT_RT. [bigeasy: +traps.c] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20191015191821.11479-2-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-08Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds1-2/+2
Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ...
2019-07-08Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds1-1/+2
Pull ARM updates from Russell King: - Add a "cut here" to make it clearer where oops dumps should be cut from - we already have a marker for the end of the dumps. - Add logging severity to show_pte() - Drop unnecessary common-page-size linker flag - Errata workarounds for Cortex A12 857271, Cortex A17 857272 and Cortex A7 814220. - Remove some unused variables that had started to provoke a compiler warning. * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8863/1: stm32: select ARM errata 814220 ARM: 8862/1: errata: 814220-B-Cache maintenance by set/way operations can execute out of order ARM: 8865/1: mm: remove unused variables ARM: 8864/1: Add workaround for I-Cache line size mismatch between CPU cores ARM: 8861/1: errata: Workaround errata A12 857271 / A17 857272 ARM: 8860/1: VDSO: Drop implicit common-page-size linker flag ARM: arrange show_pte() to issue severity-based messages ARM: add "8<--- cut here ---" to kernel dumps
2019-06-20ARM: arrange show_pte() to issue severity-based messagesRussell King1-1/+1
show_pte() is used to print information after various other kernel messages, which themselves are printed at different severities. Include the severity in the show_pte() information so that associated messages are printed with the same severity. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-06-20ARM: add "8<--- cut here ---" to kernel dumpsRussell King1-0/+1
Add a "8<--- cut here ---" marker to kernel dumps to help users cut the dump at the right place when emailing list, rather than cutting off the first line which gives the reason for the dump. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
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>
2019-05-29signal: Remove the task parameter from force_sig_faultEric W. Biederman1-1/+1
As synchronous exceptions really only make sense against the current task (otherwise how are you synchronous) remove the task parameter from from force_sig_fault to make it explicit that is what is going on. The two known exceptions that deliver a synchronous exception to a stopped ptraced task have already been changed to force_sig_fault_to_task. The callers have been changed with the following emacs regular expression (with obvious variations on the architectures that take more arguments) to avoid typos: force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)] -> force_sig_fault(\1,\2,\3) Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-29signal/arm: Remove tsk parameter from ptrace_breakEric W. Biederman1-1/+1
The ptrace_break function is always called with tsk == current. Make that obvious by removing the tsk parameter. This also makes it clear that ptrace_break calls force_sig_fault on the current task. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-01-03Remove 'type' argument from access_ok() functionLinus Torvalds1-1/+1
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-09-27signal/arm: Push siginfo generation into arm_notify_dieEric W. Biederman1-46/+17
In arm_notify_die call force_sig_fault to let the generic code handle siginfo generation. This removes some boiler plate making the code easier to maintain in the long run. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-06-04Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds1-0/+5
Pull siginfo updates from Eric Biederman: "This set of changes close the known issues with setting si_code to an invalid value, and with not fully initializing struct siginfo. There remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64 and x86 to get the code that generates siginfo into a simpler and more maintainable state. Most of that work involves refactoring the signal handling code and thus careful code review. Also not included is the work to shrink the in kernel version of struct siginfo. That depends on getting the number of places that directly manipulate struct siginfo under control, as it requires the introduction of struct kernel_siginfo for the in kernel things. Overall this set of changes looks like it is making good progress, and with a little luck I will be wrapping up the siginfo work next development cycle" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) signal/sh: Stop gcc warning about an impossible case in do_divide_error signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions signal/um: More carefully relay signals in relay_signal. signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR} signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code signal/signalfd: Add support for SIGSYS signal/signalfd: Remove __put_user from signalfd_copyinfo signal/xtensa: Use force_sig_fault where appropriate signal/xtensa: Consistenly use SIGBUS in do_unaligned_user signal/um: Use force_sig_fault where appropriate signal/sparc: Use force_sig_fault where appropriate signal/sparc: Use send_sig_fault where appropriate signal/sh: Use force_sig_fault where appropriate signal/s390: Use force_sig_fault where appropriate signal/riscv: Replace do_trap_siginfo with force_sig_fault signal/riscv: Use force_sig_fault where appropriate signal/parisc: Use force_sig_fault where appropriate signal/parisc: Use force_sig_mceerr where appropriate signal/openrisc: Use force_sig_fault where appropriate signal/nios2: Use force_sig_fault where appropriate ...
2018-05-19ARM: 8771/1: kprobes: Prohibit kprobes on do_undefinstrMasami Hiramatsu1-1/+4
Prohibit kprobes on do_undefinstr because kprobes on arm is implemented by undefined instruction. This means if we probe do_undefinstr(), it can cause infinit recursive exception. 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>
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman1-0/+5
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-02-02Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds1-2/+2
Pull ARM updates from Russell King: - StrongARM SA1111 updates to modernise and remove cruft - Add StrongARM gpio drivers for board GPIOs - Verify size of zImage is what we expect to avoid issues with appended DTB - nommu updates from Vladimir Murzin - page table read-write-execute checking from Jinbum Park - Broadcom Brahma-B15 cache updates from Florian Fainelli - Avoid failure with kprobes test caused by inappropriately placed kprobes - Remove __memzero optimisation (which was incorrectly being used directly by some drivers) * 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (32 commits) ARM: 8745/1: get rid of __memzero() ARM: 8744/1: don't discard memblock for kexec ARM: 8743/1: bL_switcher: add MODULE_LICENSE tag ARM: 8742/1: Always use REFCOUNT_FULL ARM: 8741/1: B15: fix unused label warnings ARM: 8740/1: NOMMU: Make sure we do not hold stale data in mem[] array ARM: 8739/1: NOMMU: Setup VBAR/Hivecs for secondaries cores ARM: 8738/1: Disable CONFIG_DEBUG_VIRTUAL for NOMMU ARM: 8737/1: mm: dump: add checking for writable and executable ARM: 8736/1: mm: dump: make the page table dumping seq_file ARM: 8735/1: mm: dump: make page table dumping reusable ARM: sa1100/neponset: add GPIO drivers for control and modem registers ARM: sa1100/assabet: add BCR/BSR GPIO driver ARM: 8734/1: mm: idmap: Mark variables as ro_after_init ARM: 8733/1: hw_breakpoint: Mark variables as __ro_after_init ARM: 8732/1: NOMMU: Allow userspace to access background MPU region ARM: 8727/1: MAINTAINERS: Update brcmstb entries to cover B15 code ARM: 8728/1: B15: Register reboot notifier for KEXEC ARM: 8730/1: B15: Add suspend/resume hooks ARM: 8726/1: B15: Add CPU hotplug awareness ...
2018-01-04kernel/exit.c: export abort() to modulesAndrew Morton1-1/+0
gcc -fisolate-erroneous-paths-dereference can generate calls to abort() from modular code too. [arnd@arndb.de: drop duplicate exports of abort()] Link: http://lkml.kernel.org/r/20180102103311.706364-1-arnd@arndb.de Reported-by: Vineet Gupta <Vineet.Gupta1@synopsys.com> Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Jose Abreu <Jose.Abreu@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-17ARM: probes: avoid adding kprobes to sensitive kernel-entry/exit codeRussell King1-2/+2
Avoid adding kprobes to any of the kernel entry/exit or startup assembly code, or code in the identity-mapped region. This code does not conform to the standard C conventions, which means that the expectations of the kprobes code is not forfilled. Placing kprobes at some of these locations results in the kernel trying to return to userspace addresses while retaining the CPU in kernel mode. Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-11-08Merge branch 'devel-stable' into for-nextRussell King1-0/+3
2017-11-06ARM: 8720/1: ensure dump_instr() checks addr_limitMark Rutland1-10/+18
When CONFIG_DEBUG_USER is enabled, it's possible for a user to deliberately trigger dump_instr() with a chosen kernel address. Let's avoid problems resulting from this by using get_user() rather than __get_user(), ensuring that we don't erroneously access kernel memory. So that we can use the same code to dump user instructions and kernel instructions, the common dumping code is factored out to __dump_instr(), with the fs manipulated appropriately in dump_instr() around calls to this. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-09-10ARM: implement get_tls syscallNicolas Pitre1-0/+3
When there is no dedicated register to hold the tp value and no MMU to provide a fixed address kuser helper entry point, all that is left as fallback is a syscall. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Mickael GUENE <mickael.guene@st.com> Tested-by: Vincent Abriou <vincent.abriou@st.com> Tested-by: Andras Szemzo <szemzo.andras@gmail.com>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>Ingo Molnar1-1/+1
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-15ARM: fix backtraceRussell King1-0/+20
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>
2015-10-03ARM: remove user cmpxchg syscallRussell King1-52/+0
Mark Brand reports that a NEEDS_SYSCALL_FOR_CMPXCHG enabled kernel would open a security hole in the ghost syscall used to implement cmpxchg, as it fails to validate the user pointer. However, in order for this option to be enabled, you'd need to be building a pre-ARMv6 kernel with SMP support. There is only one system known which fits that, which is an early ARM SMP FPGA implementation based on the ARM926T. In any case, the Kconfig does not allow SMP to be enabled for pre-ARMv6 systems. Moreover, even if NEEDS_SYSCALL_FOR_CMPXCHG were to be enabled, the kernel would not build as __ARM_NR_cmpxchg64 is not defined. The simple answer is to remove the buggy code. Reported-by: Mark Brand <markbrand@google.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-21ARM: domains: get rid of manager mode for user domainRussell King1-1/+0
Since we switched to early trap initialisation in 94e5a85b3be0 ("ARM: earlier initialization of vectors page") we haven't been writing directly to the vectors page, and so there's no need for this domain to be in manager mode. Switch it to client mode. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-02ARM: remove __bad_xchg definitionRussell King1-8/+0
We want link errors if xchg() is called for a variable size we do not support. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-12arm: Remove signal translation and exec_domainRichard Weinberger1-4/+2
As execution domain support is gone we can remove signal translation from the signal code and remove exec_domain from thread_info. Signed-off-by: Richard Weinberger <richard@nod.at>
2014-12-05Merge branches 'fixes', 'misc', 'pm' and 'sa1100' into for-nextRussell King1-21/+21
2014-11-27ARM: 8226/1: cacheflush: get rid of restarting blockVladimir Murzin1-29/+2
We cannot restart cacheflush safely if a process provides user-defined signal handler and signal is pending. In this case -EINTR is returned and it is expected that process re-invokes syscall. However, there are a few problems with that: * looks like nobody bothers checking return value from cacheflush * but if it did, we don't provide the restart address for that, so the process has to use the same range again * ...and again, what might lead to looping forever So, remove cacheflush restarting code and terminate cache flushing as early as fatal signal is pending. Cc: stable@vger.kernel.org # 3.12+ Reported-by: Chanho Min <chanho.min@lge.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-11-21ARM: convert printk(KERN_* to pr_*Russell King1-21/+21
Convert many (but not all) printk(KERN_* to pr_* to simplify the code. We take the opportunity to join some printk lines together so we don't split the message across several lines, and we also add a few levels to some messages which were previously missing them. Tested-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-10-02Merge branches 'fiq' (early part), 'fixes', 'l2c' (early part) and 'misc' into for-nextRussell King1-16/+1
2014-09-18ARM: remove unused do_unexp_fiq() functionRussell King1-6/+0
do_unexp_fiq() has never been called by any code in the last 10 years, it's about time it was removed! Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-09-18ARM: 8150/3: fiq: Replace default FIQ handlerDaniel Thompson1-0/+26
This patch introduces a new default FIQ handler that is structured in a similar way to the existing ARM exception handler and result in the FIQ being handled by C code running on the SVC stack (despite this code run in the FIQ handler is subject to severe limitations with respect to locking making normal interaction with the kernel impossible). This default handler allows concepts that on x86 would be handled using NMIs to be realized on ARM. Credit: This patch is a near complete re-write of a patch originally provided by Anton Vorontsov. Today only a couple of small fragments survive, however without Anton's work to build from this patch would not exist. Thanks also to Russell King for spoonfeeding me a variety of fixes during the review cycle. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-09-16ARM: 8148/1: flush TLS and thumbee register state during execNathan Lynch1-16/+1
The TPIDRURO and TPIDRURW registers need to be flushed during exec; otherwise TLS information is potentially leaked. TPIDRURO in particular needs careful treatment. Since flush_thread basically needs the same code used to set the TLS in arm_syscall, pull that into a common set_tls helper in tls.h and use it in both places. Similarly, TEEHBR needs to be cleared during exec as well. Clearing its save slot in thread_info isn't right as there is no guarantee that a thread switch will occur before the new program runs. Just setting the register directly is sufficient. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18ARM: 8074/1: traps: Make use of the frame_pointer macroNikolay Borisov1-2/+4
Use the newly-introduced frame_pointer macro to extract the correct FP based on whether we are in THUMB2 mode or not. Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-11Dump the registers on undefined instruction userspace faultsRussell King1-0/+1
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-01-21Merge branches 'amba', 'fixes', 'kees', 'misc' and 'unstable/sa11x0' into for-nextRussell King1-4/+11
2014-01-11ARM: 7939/1: traps: fix opcode endianness when read from user memoryTaras Kondratiuk1-2/+3
Currently code has an inverted logic: opcode from user memory is swapped to a proper endianness only in case of read error. While normally opcode should be swapped only if it was read correctly from user memory. Reviewed-by: Victor Kamensky <victor.kamensky@linaro.org> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-01-05ARM: fix "bad mode in ... handler" message for undefined instructionsRussell King1-1/+7
The array was missing the final entry for the undefined instruction exception handler; this commit adds it. Cc: <stable@vger.kernel.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>