This is a new promise that guards access to mmap() with MAP_FIXED.
Fixed-address mappings are rarely used, but can be useful if you are
trying to groom the process address space for malicious purposes.
None of our programs need this at the moment, as the only user of
MAP_FIXED is DynamicLoader, but the fixed mappings are constructed
before the process has had a chance to pledge anything.
We had an exception that allowed SOL_SOCKET + SO_PEERCRED on local
socket to support LibIPC's PID exchange mechanism. This is no longer
needed so let's just remove the exception.
This prevents sys$mmap() and sys$mprotect() from creating executable
memory mappings in pledged programs that don't have this promise.
Note that the dynamic loader runs before pledging happens, so it's
unaffected by this.
When mounting an Ext2FS, a block device source is required. All other
filesystem types are unaffected, as most of them ignore the source file
descriptor anyway.
Fixes#5153.
All users of this mechanism have been switched to anonymous files and
passing file descriptors with sendfd()/recvfd().
Shbufs got us where we are today, but it's time we say good-bye to them
and welcome a much more idiomatic replacement. :^)
The vast majority of programs don't ever need to use sys$ptrace(),
and it seems like a high-value system call to prevent a compromised
process from using.
This patch moves sys$ptrace() from the "proc" promise to its own,
new "ptrace" promise and updates the affected apps.
Such errors are raised when SyntaxError nodes are executed, and are also
used for internal control flow.
The 'break' and 'continue' commands are currently only allowed inside
for loops, and outside function bodies.
This also adds a 'loop' keyword for infinite loops.
Problem:
- C functions with no arguments require a single `void` in the argument list.
Solution:
- Put the `void` in the argument list of functions in C header files.
Problem:
- `(void)` simply casts the expression to void. This is understood to
indicate that it is ignored, but this is really a compiler trick to
get the compiler to not generate a warning.
Solution:
- Use the `[[maybe_unused]]` attribute to indicate the value is unused.
Note:
- Functions taking a `(void)` argument list have also been changed to
`()` because this is not needed and shows up in the same grep
command.
This is a new "browse" permission that lets you open (and subsequently list
contents of) directories underneath the path, but not regular files or any other
types of files.
It's a thin userland wrapper around adjtime(2). It can be used
to view current pending time adjustments, and root can use it to
smoothly adjust the system time.
As far as I can tell, other systems don't have a userland utility
for this, but it seems useful. Useful enough that I'm adding it to
the lagom build so I can use it on my linux box too :)
Most systems (Linux, OpenBSD) adjust 0.5 ms per second, or 0.5 us per
1 ms tick. That is, the clock is sped up or slowed down by at most
0.05%. This means adjusting the clock by 1 s takes 2000 s, and the
clock an be adjusted by at most 1.8 s per hour.
FreeBSD adjusts 5 ms per second if the remaining time adjustment is
>= 1 s (0.5%) , else it adjusts by 0.5 ms as well. This allows adjusting
by (almost) 18 s per hour.
Since Serenity OS can lose more than 22 s per hour (#3429), this
picks an adjustment rate up to 1% for now. This allows us to
adjust up to 36s per hour, which should be sufficient to adjust
the clock fast enough to keep up with how much time the clock
currently loses. Once we have a fancier NTP implementation that can
adjust tick rate in addition to offset, we can think about reducing
this.
adjtime is a bit old-school and most current POSIX-y OSs instead
implement adjtimex/ntp_adjtime, but a) we have to start somewhere
b) ntp_adjtime() is a fairly gnarly API. OpenBSD's adjfreq looks
like it might provide similar functionality with a nicer API. But
before worrying about all this, it's probably a good idea to get
to a place where the kernel APIs are (barely) good enough so that
we can write an ntp service, and once we have that we should write
a way to automatically evaluate how well it keeps the time adjusted,
and only then should we add improvements ot the adjustment mechanism.
This is implemented in Line::Editor meaning not only the Shell will
respect it, but also js, Debugger etc.
Possible values are "ignorespace", "ignoredups" and "ignoreboth", as
documented in Shell-vars(7), for now.
The default value for the anon user (set in .shellrc) is "ignoreboth".
This patchset adds the following to the manpage:
- Mention `if` expressions.
- Add section about subshells
- Mention that control structures can now be used as commands
- Update the grammar.
- Fix small header size mistake with "Example"'s being larger than their
containing sections.
This syscall allows a parent process to disown a child process, setting
its parent PID to 0.
Unparented processes are automatically reaped by the kernel upon exit,
and no sys$waitid() is required. This will make it much nicer to do
spawn-and-forget which is common in the GUI environment.
Now that we have a standalone test-js program, the "-t" test mode of the
js REPL is unused and can simply be removed. Required functionality has
been duplicated in test-js (isStrictMode function, loading of testing
utilities).
Also remove outdated information about tests from the js(1) man page.
Now that we have SystemServer that can (re)spawn the Shell, we don't need a
separate server just for that.
The two shells (on tty0 and tty1) are configured to only be started when booting
in text mode. This means you can now simply say boot_mode=text on the kernel
command line, and SystemServer will set up the system and spawn a comfy root
shell for you :^)
Services can now have their initial working directory
configured via `SystemServer.ini`.
This commit also configures Terminal's working directory
to be /home/anon
This feels a lot more consistent and Unixy:
create_shared_buffer() => shbuf_create()
share_buffer_with() => shbuf_allow_pid()
share_buffer_globally() => shbuf_allow_all()
get_shared_buffer() => shbuf_get()
release_shared_buffer() => shbuf_release()
seal_shared_buffer() => shbuf_seal()
get_shared_buffer_size() => shbuf_get_size()
Also, "shared_buffer_id" is shortened to "shbuf_id" all around.
This commit implements the `useradd` utility that is found on most,
if not all *NIX systems. It allows the root user to add new users
to the password file found in `/etc/passwd`, thereby making
it easier to manipulate the file.
This patch adds a new "accept" promise that allows you to call accept()
on an already listening socket. This lets programs set up a socket for
for listening and then dropping "inet" and/or "unix" so that only
incoming (and existing) connections are allowed from that point on.
No new outgoing connections or listening server sockets can be created.
In addition to accept() it also allows getsockopt() with SOL_SOCKET
and SO_PEERCRED, which is used to find the PID/UID/GID of the socket
peer. This is used by our IPC library when creating shared buffers that
should only be accessible to a specific peer process.
This allows us to drop "unix" in WindowServer and LookupServer. :^)
It also makes the debugging/introspection RPC sockets in CEventLoop
based programs work again.
We now pick up all the user's extra GIDs from /etc/group and make
sure those are set before exec'ing a service.
This means we finally get to enjoy being in more than one group. :^)
All threads were running with iomapbase=0 in their TSS, which the CPU
interprets as "there's an I/O permission bitmap starting at offset 0
into my TSS".
Because of that, any bits that were 1 inside the TSS would allow the
thread to execute I/O instructions on the port with that bit index.
Fix this by always setting the iomapbase to sizeof(TSS32), and also
setting the TSS descriptor's limit to sizeof(TSS32), effectively making
the I/O permissions bitmap zero-length.
This should make it no longer possible to do I/O from userspace. :^)
This prevents code running outside of kernel mode from using the
following instructions:
* SGDT - Store Global Descriptor Table
* SIDT - Store Interrupt Descriptor Table
* SLDT - Store Local Descriptor Table
* SMSW - Store Machine Status Word
* STR - Store Task Register
There's no need for userspace to be able to use these instructions so
let's just disable them to prevent information leakage.
Add an option "-A", that will run all of the crash types in the crash
program. In this mode, all crash tests are run in a child process so
that the crash program does not crash.
Crash uses the return status of the child process to ascertain whether
the crash happened as expected.
This patch makes it possible to make memory regions non-readable.
This is enforced using the "present" bit in the page tables.
A process that hits an not-present page fault in a non-readable
region will be crashed.
