Switch to using type-safe bitwise operators for the BlockFlags class,
this cleans up a lot of boilerplate casts which are necessary when the
enum is declared as `enum class`.
Mostly due to the fact that clang-format allows aligned comments via
AlignTrailingComments.
We could also use raw string literals in inline asm, which clang-format
deals with properly (and would be nicer in a lot of places).
copy_from_user can fail, for example when the user-supplied pointer is just before
the end of mapped address space. In that case, the first few bytes would get copied,
permanently overwriting the internal state of the Socket, potentially leaving it
in an inconsistent or at least difficult-to-predict state.
This may seem like a no-op change, however it shrinks down the Kernel by a bit:
.text -432
.unmap_after_init -60
.data -480
.debug_info -673
.debug_aranges 8
.debug_ranges -232
.debug_line -558
.debug_str -308
.debug_frame -40
With '= default', the compiler can do more inlining, hence the savings.
I intentionally omitted some opportunities for '= default', because they
would increase the Kernel size.
(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)
Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.
We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.
In preparation for marking BlockingResult [[nodiscard]], there are a few
places that perform infinite waits, which we never observe the result of
the wait. Instead of suppressing them, add an alternate function which
returns void when performing and infinite wait.
If we try to align a number above 0xfffff000 to the next multiple of
the page size (4 KiB), it would wrap around to 0. This is most likely
never what we want, so let's assert if that happens.
Now that we no longer need to support the signal trampolines being
user-accessible inside the kernel memory range, we can get rid of the
"kernel" and "user-accessible" flags on Region and simply use the
address of the region to determine whether it's kernel or user.
This also tightens the page table mapping code, since it can now set
user-accessibility based solely on the virtual address of a page.
Since the payload size is user-controlled, this could be used to
overflow the kernel stack.
We should probably also be breaking things into smaller packets at a
higher level, e.g TCPSocket::protocol_send(), but let's do that as
a separate exercise.
Fixes#5310.
* We don't have to lock the "all IPv4 sockets" in exclusive mode, shared mode is
enough for just reading the list (as opposed to modifying it).
* We don't have to lock socket's own lock at all, the IPv4Socket::did_receive()
implementation takes care of this.
* Most importantly, we don't have to hold the "all IPv4 sockets" across the
IPv4Socket::did_receive() call(s). We can copy the current ICMP socket list
while holding the lock, then release the lock, and then call
IPv4Socket::did_receive() on all the ICMP sockets in our list.
These changes fix a deadlock triggered by receiving ICMP messages when using tap
networking setup (as opposed to QEMU's default user/SLIRP networking) on the host.
This was done with the help of several scripts, I dump them here to
easily find them later:
awk '/#ifdef/ { print "#cmakedefine01 "$2 }' AK/Debug.h.in
for debug_macro in $(awk '/#ifdef/ { print $2 }' AK/Debug.h.in)
do
find . \( -name '*.cpp' -o -name '*.h' -o -name '*.in' \) -not -path './Toolchain/*' -not -path './Build/*' -exec sed -i -E 's/#ifdef '$debug_macro'/#if '$debug_macro'/' {} \;
done
# Remember to remove WRAPPER_GERNERATOR_DEBUG from the list.
awk '/#cmake/ { print "set("$2" ON)" }' AK/Debug.h.in
For some reason we were keeping the bits 04777 in file modes. That
doesn't seem right and I can't think of a reason why the set-uid bit
should be allowed to slip through.
..and allow implicit creation of KResult and KResultOr from ErrnoCode.
This means that kernel functions that return those types can finally
do "return EINVAL;" and it will just work.
There's a handful of functions that still deal with signed integers
that should be converted to return KResults.
We forgot to remove the automatic SMAP disablers after fixing up all
this code to not access userspace memory directly. Let's lock things
down at last. :^)
Problem:
- Many constructors are defined as `{}` rather than using the ` =
default` compiler-provided constructor.
- Some types provide an implicit conversion operator from `nullptr_t`
instead of requiring the caller to default construct. This violates
the C++ Core Guidelines suggestion to declare single-argument
constructors explicit
(https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c46-by-default-declare-single-argument-constructors-explicit).
Solution:
- Change default constructors to use the compiler-provided default
constructor.
- Remove implicit conversion operators from `nullptr_t` and change
usage to enforce type consistency without conversion.
