By having a separate list of constructors for the kernel heap
code, we can properly use constructors without re-running them
after the heap was already initialized. This solves some problems
where values were wiped out because they were overwritten by
running their constructors later in the initialization process.
If a buffer smaller than Elf32_Ehdr was passed to Image, header()
would do an out-of-bounds read.
Make parse() check for that. Make most Image methods assert that the image
is_valid(). For that to work, set m_valid early in Image::parse()
instead of only at its end.
Also reorder a few things so that the fuzzer doesn't hit (valid)
assertions, which were harmless from a security PoV but which still
allowed userspace to crash the kernel with an invalid ELF file.
Make dbgprintf()s configurable at run time so that the fuzzer doesn't
produce lots of logspam.
Userspace<void*> is a bit strange here, as it would appear to the
user that we intend to de-refrence the pointer in kernel mode.
However I think it does a good join of illustrating that we are
treating the void* as a value type, instead of a pointer type.
This compiles, and fixes two bugs:
- setpgid() confusion (see previous commit)
- tcsetpgrp() now allows to set a non-empty process group even if
the group leader has already died. This makes Serenity slightly
more POSIX-compatible.
This compiles, and contains exactly the same bugs as before.
The regex 'FIXME: PID/' should reveal all markers that I left behind, including:
- Incomplete conversion
- Issues or things that look fishy
- Actual bugs that will go wrong during runtime
Technically, this can be 'exploited' to set the pgid of an exploiting process
to a near-arbitrary new pgid. This can cause conflicts when assigning future pgids,
destroys the session-boundary, and might confuse future pgid-to-session lookups.
In practice, I can't come up with a way that this causes actual harm.
This template class allows for easy generation of incompatible numeric types.
This is useful whenever code has to handle heterogenous data (like meters and
seconds) but the underlying data types are compatible (like int and int).
The motivation comes from the Kernel's inconsistent use of pid_t for process and
thread IDs even though the ID spaces are incompatible, and translating forth/back
is nontrivial.
Other uses could be units (as described above), or incompatible index systems.
A popular use in real life is image manipulation, when there are multiple
coordinate systems.