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
...
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 as published by
the free software foundation version 2 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
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 97 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.025053186@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
Update the calls of force_sig_fault that pass in a variable that is
set to current earlier to explicitly use current.
This is to make the next change that removes the task parameter
from force_sig_fault easier to verify.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The do_trap function is always called with tsk == current.
Make that obvious by removing the tsk parameter.
This also makes it clear that do_trap calls force_sig_fault
on the current task.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The kernel module is loaded into vmalloc region which is located below
to the PAGE_OFFSET. Hence the condition, pc < PAGE_OFFSET, in the
is_valid_bugaddr() will filter out all trap exceptions triggered
by kernel module. To support BUG() in kernel module, the condition is
changed to pc < VMALLOC_START.
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The macro __BUG_INSN currently is defined as the "ebreak" opcode.
The is_valid_bugaddr() function compares the instruction pointed to by
$sepc with macro __BUG_INSN to check whether the current trap exception
is caused by an "ebreak" instruction. However, this check flow is possibly
erroneous because if C extension is supported, the expected trap
instruction "ebreak" is possibly translated to "c.ebreak" by the assembler.
Therefore, it requires a mechanism to distinguish the length of the
instruction in $spec and compare it to the correct trap instruction.
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We should prefer accessing CSRs using their CSR numbers because:
1. It compiles fine with older toolchains.
2. We can use latest CSR names in #define macro names of CSR numbers
as-per RISC-V spec.
3. We can access newly added CSRs even if toolchain does not recognize
newly addes CSRs by name.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Adding 4 to sepc is pointless, and is wrong if we executed a 2-byte
compressed breakpoint. This plus a corresponding gdb patch allows
compressed breakpoints to work in gdb. Gdb maintainers have already
agreed that this is the right approach.
Signed-off-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This tag contains some small RISC-V updates I'd like to target for 4.18.
They are all fairly small this time. Here's a short summary, there's
more info in the commits/merges.
* A fix to __clear_user to respect the passed arguments.
* Enough support for the perf subsystem to work with RISC-V's ISA
defined performance counters.
* Support for sparse and cleanups suggested by it.
* Support for R_RISCV_32 (a relocation, not the 32-bit ISA).
* Some MAINTAINERS cleanups.
* The addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's always
present.
I've given these a simple build+boot test.
-----BEGIN PGP SIGNATURE-----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=D+sb
-----END PGP SIGNATURE-----
Merge tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V updates from Palmer Dabbelt:
"This contains some small RISC-V updates I'd like to target for 4.18.
They are all fairly small this time. Here's a short summary, there's
more info in the commits/merges:
- a fix to __clear_user to respect the passed arguments.
- enough support for the perf subsystem to work with RISC-V's ISA
defined performance counters.
- support for sparse and cleanups suggested by it.
- support for R_RISCV_32 (a relocation, not the 32-bit ISA).
- some MAINTAINERS cleanups.
- the addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's
always present.
I've given these a simple build+boot test"
* tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
RISC-V: Add CONFIG_HVC_RISCV_SBI=y to defconfig
RISC-V: Handle R_RISCV_32 in modules
riscv/ftrace: Export _mcount when DYNAMIC_FTRACE isn't set
riscv: add riscv-specific predefines to CHECKFLAGS
riscv: split the declaration of __copy_user
riscv: no __user for probe_kernel_address()
riscv: use NULL instead of a plain 0
perf: riscv: Add Document for Future Porting Guide
perf: riscv: preliminary RISC-V support
MAINTAINERS: Update Albert's email, he's back at Berkeley
MAINTAINERS: Add myself as a maintainer for SiFive's drivers
riscv: Fix the bug in memory access fixup code
In is_valid_bugaddr(), probe_kernel_address() is called with
the PC casted to (bug_inst_t __user *) but this function
only take a plain void* as argument, not a __user pointer.
Fix this by removing the unnneded __user in the cast.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The function force_sig_fault is just the generic version of
do_trap_siginfo with a (void __user *) instead of an unsigned long
parameter for the address.
So just use force_sig_fault to simplify the code.
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: linux-riscv@lists.infradead.org
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.
Simplify this process by using the helper force_sig_fault. Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.
In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: linux-riscv@lists.infradead.org
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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>
This contains the various __init C functions, the initial assembly
kernel entry point, and the code to reset the system. When a file was
init-related this patch contains the entire file.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
