Since kernel commit 6693731487a8 ("vsock/virtio: Allocate nonlinear SKBs
for handling large transmit buffers"), a large vsock packet can be split
into multiple descriptors.
If we encounter such TX packets, pull the content into an owned buffer.
Fixes: #7672
Signed-off-by: Wei Liu <liuwe@microsoft.com>
VsockPacket::hdr holds a raw pointer to the address of the VSock packet
header, which is in guest memory. It opens the door to double-fetch
(or TOCTOU) race conditions. Therefore, VSockPacket::hdr content can't
be trusted since it can be arbitrarily changed by the guest, at any
time.
To mitigate this, we can copy the header content to an array in VMM's
memory that the guest can't modify.
Signed-off-by: Thomas Leroy <thomas.leroy.mp@gmail.com>
This is a follow-up of [0].
# Advantages
- This saves dozens of unneeded clone()s across the whole code base
- Makes it much easier to reason about how parameters are used
(often we passed owned Arc/Rc versions without actually needing
ownership)
# Exceptions
For certain code paths, the alternatives would require awkward or overly
complex code, and in some cases the functions are the logical owners of
the values they take. In those cases, I've added
#[allow(clippy::needless_pass_by_value)].
This does not mean that one should not improve this in the future.
[0] 6a86c157af
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
This better aligns with the rest of the code and makes it clearer
that these tests can run "as is" in a normal hosted environments
without the special test environment.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
Consuming `&Arc<T>` as argument is almost always an antipattern as it
hides whether the callee is going to take over (shared) ownership
(by .clone()) or not. Instead, it is better to consume `&dyn T` or
`Arc<dyn T>` to be more explicit. This commit cleans up the code.
The change is very mechanic and was very easy to implement across the
code base.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
Fix clippy warning `uninlined_format_args` reported by rustc rustc
1.89.0 (29483883e 2025-08-04).
```console
warning: variables can be used directly in the `format!` string
--> block/src/lib.rs:649:17
|
649 | info!("{} failed to create io_uring instance: {}", error_msg, e);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
= note: `#[warn(clippy::uninlined_format_args)]` on by default
help: change this to
|
649 - info!("{} failed to create io_uring instance: {}", error_msg, e);
649 + info!("{error_msg} failed to create io_uring instance: {e}");
|
```
Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>
The function `read_local_stream_port` had no proper handling for
unexpected or incomplete input.
When the control socket of the VSOCK device was closed without sending
the expected `CONNECT <PORT>\n` statement completely, the thread
got stuck in an infinite loop as it attempted to read from a closed
socket over and over again which never returned any data.
This resulted in the thread responsible for `epoll` being completely
blocked. New VSOCK connections could not be established and existing
ones became defunct, effectively leading to a Denial of Service of
the entire VSOCK device.
The issue can be reproduced by opening a socket and immediately
closing it.
```
socat - UNIX-CONNECT:/socket.vsock
<Ctrl-C>
```
Instead of applying a quick fix by handling the `EPOLLHUP` event before
reading, the function is refactored to remove the error-prone `while`
loop and multiple `read`s.
Notably, we now check if the number of bytes read is zero, which occurs
when `event_set == EPOLLHUP | EPOLLIN`, indicating that the socket has
been closed by the client.
Additionally, the actual parsing code is now extracted into a dedicated
function that is tested.
Fixes: #6798
Signed-off-by: Maximilian Güntner <code@mguentner.de>
The read_exact() call was introduced in 82ac114b8 ("virtio-devices:
vsock: handle short read in muxer") to solve a crash when a connection
disconnected without sending any data, but it introduced a problem of
its own: because the socket is non-blocking, read_exact() may read
some data, then return ErrorKind::WouldBlock. In that case, the data
it read will be discarded. So for example if it read "CONNECT ",
and then nothing else was available to read yet, "CONNECT " would be
discarded, and so the next time this function was called, when epoll
triggered again for the socket, only the following data would end up
in command.buf, causing an error due to just a port number being an
invalid command.
Contrary to that commit message, this code was actually designed to
handle short reads just fine — in the case of a short read, it stores
the data it has read in command, and returns
Error::UnixRead(ErrorKind::WouldBlock), which is ignored by the
caller, and the function gets called again when there is more data to
read, building up command potentially over the course of several
reads. The only thing it didn't handle correctly, as far as I can
tell, was a 0-byte read, which happens when a client disconnects from
the socket without writing anything. All that's needed to fix this is
to avoid an invalid subtraction in that case, so this change reverts
82ac114b8, fixing the issue with partial commands being discarded, and
instead handles the 0-byte read by using slice::get, and treating an
empty command as an incomplete command, which of course it is.
Fixes: 82ac114b8 ("virtio-devices: vsock: handle short read in muxer")
Signed-off-by: Alyssa Ross <hi@alyssa.is>
This was caught by the nightly compiler during cargo fuzz build.
error: lifetime flowing from input to output with different syntax can be confusing
--> /home/runner/work/cloud-hypervisor/cloud-hypervisor/hypervisor/src/arch/x86/emulator/mod.rs:493:26
|
493 | pub fn new(platform: &mut dyn PlatformEmulator<CpuState = T>) -> Emulator<T> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ----------- the lifetime gets resolved as `'_`
| |
| this lifetime flows to the output
|
= note: `-D mismatched-lifetime-syntaxes` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(mismatched_lifetime_syntaxes)]`
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
|
493 | pub fn new(platform: &mut dyn PlatformEmulator<CpuState = T>) -> Emulator<'_, T> {
Signed-off-by: Jinank Jain <jinankjain@microsoft.com>
This streamlines the code base to follow best practices for
error handling in Rust: Each error struct implements
std::error::Error (most due via thiserror::Error derive macro)
and sets its source accordingly.
This allows future work that nicely prints the error chains,
for example.
So far, the convention is that each error prints its
sub error as part of its Display::fmt() impl.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
Instead of reinventing this mock infrastructure in the upcoming fuzzer,
reuse the one that is already available.
However this change makes Clippy complain that TestBackend and
TestContext don't implement Default. This is just test code, we can
suppress Clippy in this case.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Asserting on .is_ok()/.is_err() leads to hard to debug failures (as if
the test fails, it will only say "assertion failed: false". We replace
these with `.unwrap()`, which also prints the exact error variant that
was unexpectedly encountered (we can to this these days thanks to
efforts to implement Display and Debug for our error types). If the
assert!((...).is_ok()) was followed by an .unwrap() anyway, we just drop
the assert.
Inspired by and quoted from @roypat.
Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>
By introducing `imports_granularity="Module"` format strategy,
effectively groups imports from the same module into one line or block,
improving maintainability and readability.
Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>
Historically the Cloud Hypervisor coding style has been to ensure that
all imports are ordered and placed in a single group. Unfortunately
cargo fmt has no support for ensuring that all imports are in a single
group so if whitespace lines were added as part of the import statements
then they would only be odered correctly in the group.
By adopting "group_imports="StdExternalCrate" we can enforce a style
where imports are placed in at most three groups for std, external
crates and the crate itself. Choosing a style enforceable by the tooling
reduces the reviewer burden.
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
An example warning output is:
error: first doc comment paragraph is too long
--> virtio-devices/src/lib.rs:158:1
|
158 | / /// Convert an absolute address into an address space (GuestMemory)
159 | | /// to a host pointer and verify that the provided size define a valid
160 | | /// range within a single memory region.
161 | | /// Return None if it is out of bounds or if addr+size overlaps a single region.
| |_
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#too_long_first_doc_paragraph
= note: `-D clippy::too-long-first-doc-paragraph` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::too_long_first_doc_paragraph)]`
Signed-off-by: Bo Chen <chen.bo@intel.com>
The mem_size field is not needed in TestContext. Drop it.
Make sure guest_evvq is read once. Clippy cannot figured out that it was
used.
While at it, add an extra assert for the spurious rxvq event test, too.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
With the nightly toolchain (2024-02-18) cargo check will flag up
redundant imports either because they are pulled in by the prelude on
earlier match.
Remove those redundant imports.
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
The VIRTIO specification[1] says:
> The upper 32 bits of the CID are reserved and zeroed.
We should therefore not allow the user to supply a VSOCK CID with
those bits set. To accomplish this, limit the public API of the
virtio-vsock device to only accept 32-bit CIDs, while still using
64-bit CIDs internally since that's how virtio-vsock works.
[1]: https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-4400004
Signed-off-by: Alyssa Ross <hi@alyssa.is>
The socket is nonblocking, so it's not guaranteed that it will be
possible to read the whole connect command in a single iteration of
the event loop. To reproduce:
(echo -n 'CONNECT '; sleep 1; echo 1234; cat) | socat STDIO UNIX-CONNECT:vsock.sock
This would produce the error:
cloud-hypervisor: 5.509209s: <_vsock4> INFO:virtio-devices/src/vsock/unix/muxer.rs:446 -- vsock: error adding local-init connection: UnixRead(Os { code: 11, kind: WouldBlock, message: "Resource temporarily unavailable" })
To fix this, if we only get a partial command, we need to save it for
future iterations of the event loop, and only proceed once we've read
a complete command.
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Since kernel v6.3 the vsock packet is not split over two descriptors
and is instead included in a single one.
This change is based on the discovery and fix identified by Stefano
Garzarella for the vm-virtio vsock implementation and adapted for our
very different codebase.
Fixes: #5691
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
warning: usage of `Arc<T>` where `T` is not `Send` or `Sync`
--> virtio-devices/src/vsock/device.rs:376:22
|
376 | backend: Arc::new(RwLock::new(backend)),
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: consider using `Rc<T>` instead or wrapping `T` in a std::sync type like `Mutex<T>`
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#arc_with_non_send_sync
= note: `#[warn(clippy::arc_with_non_send_sync)]` on by default
The vsock backend may be shared between threads, so the type `B` in
`Vsock` should be `VsockBackend` and `Sync`.
Considering that `api_receiver` and `gdb_receiver` are only used in vmm
threads, the `Arc` can be replaced by `Rc`.
Signed-off-by: Yu Li <liyu.yukiteru@bytedance.com>
warning: useless use of `vec!`
--> test_infra/src/lib.rs:111:30
|
111 | let mut events = vec![epoll::Event::new(epoll::Events::empty(), 0); 1];
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: you can use an array directly: `[epoll::Event::new(epoll::Events::empty(), 0); 1]`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_vec
= note: `#[warn(clippy::useless_vec)]` on by default
Signed-off-by: Yu Li <liyu.yukiteru@bytedance.com>
warning: casting raw pointers to the same type and constness is unnecessary (`*const protocol::MemoryRange` -> `*const protocol::MemoryRange`)
--> vm-migration/src/protocol.rs:280:17
|
280 | self.data.as_ptr() as *const MemoryRange as *const u8,
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `self.data.as_ptr()`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_cast
= note: `#[warn(clippy::unnecessary_cast)]` on by default
Signed-off-by: Yu Li <liyu.yukiteru@bytedance.com>
Doc comments are Markdown, and can include HTML tags. Anything in
angle brackets will therefore be inserted as an HTML tag into
rustdoc's output. If that's not intentional, the left angle bracket
needs to be escaped.
I haven't fixed the doc comments in src/main.rs, because argh doesn't
understand the escaping, so the backslashes would show up in the
--help output. I've opened https://github.com/google/argh/issues/159
about that.
Signed-off-by: Alyssa Ross <hi@alyssa.is>
These need to be //! comments, because they apply to the module as a
whole, not to whatever directly follows the comment. Using ///
comments here resulted in documentation being attached to the wrong
thing, or not rendered at all.
I've also checked the Markdown formatting of these comments as
rendered by rustdoc, and fixed it where appropriate.
Signed-off-by: Alyssa Ross <hi@alyssa.is>
