[ Upstream commit 32d59773da38cd83e497a70eb9754d4bbae3aeae ] Wire up TIF_NOTIFY_SIGNAL handling for arm. Cc: linux-arm-kernel@lists.infradead.org Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b9baf5c8c5c356757f4f9d8180b5e9d234065bc3 upstream. Workaround the Spectre BHB issues for Cortex-A15, Cortex-A57, Cortex-A72, Cortex-A73 and Cortex-A75. We also include Brahma B15 as well to be safe, which is affected by Spectre V2 in the same ways as Cortex-A15. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [changes due to lack of SYSTEM_FREEING_INITMEM - gregkh] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
On at least x86 and ARM64, and as documented in the ptrace man page
a skipped system call will still cause a syscall exit ptrace stop.
Previous to this commit 32-bit ARM did not, resulting in strace
being confused when seccomp skips system calls.
This change also impacts programs that use ptrace to skip system calls.
Fixes: ad75b51459ae ("ARM: 7579/1: arch/allow a scno of -1 to not cause a SIGILL")
Signed-off-by: Timothy E Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Signed-off-by: Eugene Syromyatnikov <evgsyr@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Eugene Syromyatnikov <evgsyr@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
When building the kernel as Thumb-2 with binutils 2.29 or newer, if the
assembler has seen the .type directive (via ENDPROC()) for a symbol, it
automatically handles the setting of the lowest bit when the symbol is
used with ADR. The badr macro on the other hand handles this lowest bit
manually. This leads to a jump to a wrong address in the wrong state
in the syscall return path:
Internal error: Oops - undefined instruction: 0 [#2] SMP THUMB2
Modules linked in:
CPU: 0 PID: 652 Comm: modprobe Tainted: G D 4.18.0-rc3+ #8
PC is at ret_fast_syscall+0x4/0x62
LR is at sys_brk+0x109/0x128
pc : [<80101004>] lr : [<801c8a35>] psr: 60000013
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 50c5387d Table: 9e82006a DAC: 00000051
Process modprobe (pid: 652, stack limit = 0x(ptrval))
80101000 <ret_fast_syscall>:
80101000: b672 cpsid i
80101002: f8d9 2008 ldr.w r2, [r9, #8]
80101006: f1b2 4ffe cmp.w r2, #2130706432 ; 0x7f000000
80101184 <local_restart>:
80101184: f8d9 a000 ldr.w sl, [r9]
80101188: e92d 0030 stmdb sp!, {r4, r5}
8010118c: f01a 0ff0 tst.w sl, #240 ; 0xf0
80101190: d117 bne.n 801011c2 <__sys_trace>
80101192: 46ba mov sl, r7
80101194: f5ba 7fc8 cmp.w sl, #400 ; 0x190
80101198: bf28 it cs
8010119a: f04f 0a00 movcs.w sl, #0
8010119e: f3af 8014 nop.w {20}
801011a2: f2af 1ea2 subw lr, pc, #418 ; 0x1a2
To fix this, add a new symbol name which doesn't have ENDPROC used on it
and use that with badr. We can't remove the badr usage since that would
would cause breakage with older binutils.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Pull restartable sequence support from Thomas Gleixner: "The restartable sequences syscall (finally): After a lot of back and forth discussion and massive delays caused by the speculative distraction of maintainers, the core set of restartable sequences has finally reached a consensus. It comes with the basic non disputed core implementation along with support for arm, powerpc and x86 and a full set of selftests It was exposed to linux-next earlier this week, so it does not fully comply with the merge window requirements, but there is really no point to drag it out for yet another cycle" * 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rseq/selftests: Provide Makefile, scripts, gitignore rseq/selftests: Provide parametrized tests rseq/selftests: Provide basic percpu ops test rseq/selftests: Provide basic test rseq/selftests: Provide rseq library selftests/lib.mk: Introduce OVERRIDE_TARGETS powerpc: Wire up restartable sequences system call powerpc: Add syscall detection for restartable sequences powerpc: Add support for restartable sequences x86: Wire up restartable sequence system call x86: Add support for restartable sequences arm: Wire up restartable sequences system call arm: Add syscall detection for restartable sequences arm: Add restartable sequences support rseq: Introduce restartable sequences system call uapi/headers: Provide types_32_64.h
Syscalls are not allowed inside restartable sequences, so add a call to rseq_syscall() at the very beginning of system call exiting path for CONFIG_DEBUG_RSEQ=y kernel. This could help us to detect whether there is a syscall issued inside restartable sequences. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Joel Fernandes <joelaf@google.com> Cc: Peter Zijlstra <peterz@infradead.org> 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: 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: https://lkml.kernel.org/r/20180602124408.8430-5-mathieu.desnoyers@efficios.com
Prevent speculation at the syscall table decoding by clamping the index used to zero on invalid system call numbers, and using the csdb speculative barrier. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
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>