The check of ensuring we are not trying to read beyond the end of the
inode data buffer is already there, it's just that we need to disallow
further reading if the read offset equals to the inode data size.
Apparently we lacked this important check from the beginning of this
piece of code. This check is crucial to ensure we only give back data
being related to the FATInode data buffer and nothing beyond it.
This is necessary to support the wayland protocol.
I also moved the CMSG_* macros to the kernel API since they are used in
both kernel and userspace.
this does not break ntpquery/SCM_TIMESTAMP.
There was a bug in which bound Inodes would lose all their references
(because localsocket does not reference them), and they would be
deallocated, and clients would get ECONNREFUSED as a result. now
LocalSocket has a strong reference to inode so that the inode will live
as long as the socket, and Inode has a weak reference to the socket,
because if the socket stops being referenced anywhere it should not be
bound.
This still prevents the reference loop that
220b7dd779 was trying to fix.
Even though we currently build all of Userland and the Kernel with the
-mstrict-align flag, the compiler will still emit unaligned memory
accesses. To work around this, we disable the check for now. See
https://github.com/SerenityOS/serenity/issues/17516 for the relevant
issue.
This commit adds Processor::set_thread_specific_data, and this function
is used to factor out architecture specific implementation of setting
the thread specific data. This function is implemented for
aarch64 and x86_64, and the callsites are changed to use this function
instead.
This new method is meant to be used in both userspace and kernel code.
The idea is to allow printing of a verbose message and then returning an
errno code which is the proper mechanism for kernel code because we
should almost always assume that such error will be propagated back to
userspace in some way, so the userspace code could reasonably decode it.
For userspace code however, this new method is meant to be a simple
wrapper for Error::from_string_view, because for most invocations, it's
much more useful to have a verbose & literal error than a errno code, so
we simply ignore that errno code completely in such context.
Returning literal strings is not the proper action here, because we
should always assume that error could be propagated back to userland, so
we need to keep a valid errno when returning an Error.
Returning literal strings is not the proper action here, because we
should always assume that error could be propagated back to userland, so
we need to keep a valid errno when returning an Error.
For example, consider cases where we want to propagate errors only in
specific instances:
auto result = read_data(); // something like ErrorOr<ByteBuffer>
if (result.is_error() && result.error().code() != EINTR)
continue;
auto bytes = TRY(result);
The TRY invocation will currently copy the byte buffer when the
expression (in this case, just a local variable) is stored into
_temporary_result.
This patch binds the expression to a reference to prevent such copies.
In less trival invocations (such as TRY(some_function()), this will
incur only temporary lifetime extensions, i.e. no functional change.
This is needed so we can retrieve the registers of a traced
thread that was attached to while it was running.
Attaching with ptrace to a running thread sends SIGSTOP to it.
This adds the necessary code to init.cpp to be able to execute the first
userspace process. To do this, first the filesystem code is initialized,
which will use the ramdisk embedded into the kernel image. Then the
first userspace process, /bin/SystemServer is executed. :^)
The ramdisk code is used as it is useful for the bring-up of the aarch64
port, however once the kernel has support for better ram-based
filesystems, the ramdisk code will be removed again.
The emulated aarch64 CPU does not contain the RNG cpu feature, so the
random number generator was not seeded. This commit adds a fallback to
use TimeManagement as a entropy source, such that get_good_random_bytes
works, which is needed for running the first userspace application on
aarch64.
This sets up the correct ThreadRegisters state when a process is
exec'ed, which happens when the first userspace application is executed.
Also changes Processor.cpp to get the stack pointer from the
ThreadRegisters.
This allows the function to be called from other translation units, in
particular this allows the CrashHandler.cpp file to be shared between
aarch64 and x86_64.
Setting the kernel_load_base variable caused backtracking to regress, so
to have proper backtracing the calculation of the symbol address in
KSyms.cpp needs to keep into account that the aarch64 kernel is linked
at a high virtual memory address.
When we execute in userspace, the exception level is EL0, so to handle
exceptions, such as interrupts, and syscalls, we need to add handlers to
vector_table.S. For now we only support running userspace applications
in AArch64 mode, so this commit only adds the handlers for that mode.
