If we're flushing user space pointers and the process only has one
thread, we do not need to broadcast this to other processors as
they will all discard that request anyway.
We were failing to round down the base of partial VM ranges. This led
to split regions being constructed that could have a non-page-aligned
base address. This would then trip assertions in the VM code.
Found by fuzz-syscalls. :^)
If a program attempts to write from more than a million different locations,
there is likely shenaniganery afoot! Refuse to write to prevent kmem exhaustion.
Found by fuzz-syscalls. Can be reproduced by running this in the Shell:
$ syscall writev 1 [ 0 ] 0x08000000
Found by fuzz-syscalls. Can be reproduced by running this in the Shell:
$ syscall exit_thread
This leaves the process in the 'Dying' state but never actually removes it.
Therefore, avoid this scenario by pretending to exit the entire process.
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.
Not sure why this was 4 MiB in the first place, but that's a lot of
memory to reserve for each thread when we're running with 512 MiB
total in the default testing setup. :^)
* 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.
The way we read/write directories is very inefficient, and this doesn't
solve any of that. It does however reduce memory usage of directory
entry vectors by 25% which has nice immediate benefits.
CLion doesn't understand that we switch compilers mid-build (which I
can understand since it's a bit unusual.) Defining __serenity__ makes
the majority of IDE features work correctly in the kernel context.
sys$fork() already takes care of children inheriting the parent's root
directory, so there was no need to do the same thing when creating a
new user process.
Add a per-process ptrace lock and use it to prevent ptrace access to a
process after it decides to commit to a new executable in sys$execve().
Fixes#5230.
