This was a mistake in the move away from KBuffer-as-a-value type.
We need to check `packet` here, not `packet->data`.
Regressed in b300f9aa2f.
Fixes#9888.
This was a weird KBuffer API that assumed failure was impossible.
This patch converts it to a modern KResultOr<NonnullOwnPtr<KBuffer>> API
and updates the two clients to the new style.
Sockets remember their last error code in the SO_ERROR field, so we need
to take special care to remember this when returning an error.
This patch adds a SOCKET_TRY() that works like TRY() but also calls
set_so_error() on the failure path.
There's probably a lot more code that should be using this, but that's
outside the scope of this patch.
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
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.
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.
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.
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.
This commit converts naked `new`s to `AK::try_make` and `AK::try_create`
wherever possible. If the called constructor is private, this can not be
done, so we instead now use the standard-defined and compiler-agnostic
`new (nothrow)`.
Instead of initializing network adapters in init.cpp, let's move that
logic into a separate class to handle this.
Also, it seems like a good idea to shift responsiblity on enumeration
of network adapters after the boot process, so this singleton will take
care of finding the appropriate network adapter when asked to with an
IPv4 address or interface name.
With this change being merged, we simplify the creation logic of
NetworkAdapter derived classes, so we enumerate the PCI bus only once,
searching for driver candidates when doing so, and we let each driver
to test if it is resposible for the specified PCI device.
When attempting to write to a socket that is not connected or - for
connection-less protocols - doesn't have a peer address set we should
return EPIPE instead of blocking the thread.
Previously we'd allocate buffers when sending packets. This patch
avoids these allocations by using the NetworkAdapter's packet queue.
At the same time this also avoids copying partially constructed
packets in order to prepend Ethernet and/or IPv4 headers. It also
properly truncates UDP and raw IP packets.
Note that the changes to IPv4Socket::create are unfortunately needed as
the return type of TCPSocket::create and IPv4Socket::create don't match.
- KResultOr<NonnullRefPtr<TcpSocket>>>
vs
- KResultOr<NonnullRefPtr<Socket>>>
To handle this we are forced to manually decompose the KResultOr<T> and
return the value() and error() separately.
This matches what other operating systems like Linux do:
$ ip route get 0.0.0.0
local 0.0.0.0 dev lo src 127.0.0.1 uid 1000
cache <local>
$ ssh 0.0.0.0
gunnar@0.0.0.0's password:
$ ss -na | grep :22 | grep ESTAB
tcp ESTAB 0 0 127.0.0.1:43118 127.0.0.1:22
tcp ESTAB 0 0 127.0.0.1:22 127.0.0.1:43118
An IP socket can now join a multicast group by using the
IP_ADD_MEMBERSHIP sockopt, which will cause it to start receiving
packets sent to the multicast address, even though this address does
not belong to this host.
Raw sockets don't need a local port, so we shouldn't fail operations
if allocation yields an ENOPROTOOPT.
I'm not in love with the factoring here, just patching up the bug.
This commit will add MSG_PEEK support, which allows a package to be
seen without taking it from the buffer, so that a subsequent recv()
without the MSG_PEEK flag can pick it up.
