This has several benefits:
1) We no longer just blindly derefence a null pointer in various places
2) We will get nicer runtime error messages if the current process does
turn out to be null in the call location
3) GCC no longer complains about possible nullptr dereferences when
compiling without KUBSAN
Previously when trying to debug the system's routing, the ARP
information would clutter the output and make it difficult to focus on
the routing decisions. It would be better to specify these
debug messages under ARP_DEBUG.
This patch removes KResult::operator int() and deals with the fallout.
This forces a lot of code to be more explicit in its handling of errors,
greatly improving readability.
When TCP sockets successfully establish a connection, any SO_ERROR
should be cleared back to success. For example, SO_ERROR gets set to
EINPROGRESS on asynchronous connect calls and should be cleared when
the socket moves to the Established state.
The only two paths for copying strings in the kernel should be going
through the existing Userspace<char const*>, or StringArgument methods.
Lets enforce this by removing the option for using the raw cstring APIs
that were previously available.
This fixes the placeholder stub for the SO_ERROR via getsockopt. It
leverages the m_so_error value that each socket maintains. The SO_ERROR
option obtains and then clears this field, which is useful when checking
for errors that occur between socket calls. This uses an integer value
to return the SO_ERROR status.
Resolves#146
Note: TCPSocket::create_client() has a dubious locking process where
the sockets by tuple table is first shared lock to check if the socket
exists and bail out if it does, then unlocks, then exclusively locks to
add the tuple. There could be a race condition where two client
creation requests for the same tuple happen at the same time and both
cleared the shared lock check. When in doubt, lock exclusively the
whole time.
Now that all KResult and KResultOr are used consistently throughout the
kernel, it's no longer necessary to return negative error codes.
However, we were still doing that in some places, so let's fix all those
(bugs) by removing the minuses. :^)
The IPv4Socket requires a DoubleBuffer for storage of any data it
received on the socket. However it was previously using the default
constructor which can not observe allocation failure. Address this by
plumbing the receive buffer through the various derived classes.
LocalSockets keep a DoubleBuffer for both client and server usage.
This change converts the usage from using the default constructor
which is unable to observe OOM, to the new try_create factory and
plumb the result through the constructor.
Read the appropriate registers for RTL8139, RTL8168 and E1000.
For NE2000 just assume 10mbit full duplex as there is no indicator
for it in the pure NE2000 spec. Mock values for loopback.
Previously there was no way for Serenity to send a packet without an
established socket connection, and there was no way to appropriately
respond to a SYN packet on a non-listening port. This patch will respond
to any non-established socket attempts with the appropraite RST/ACK,
letting the client know to close the connection.
In accordance with RFC 793, if the receiver is in the SYN-SENT state
it should respond to a RST by aborting the connection and immediately
move to the CLOSED state.
Previously the system would ACK all RST/ACKs, and the remote peer would
just respond with more RST packets.
Previously it was possible to leak the file descriptor if we error out
after allocating the first descriptor. Now we perform both fd
allocations back to back so we can handle the potential error when
processing the second fd allocation.
It's easy to forget the responsibility of validating and safely copying
kernel parameters in code that is far away from syscalls. ioctl's are
one such example, and bugs there are just as dangerous as at the root
syscall level.
To avoid this case, utilize the AK::Userspace<T> template in the ioctl
kernel interface so that implementors have no choice but to properly
validate and copy ioctl pointer arguments.
