Get/Set pipe size and ioctl support were missing from
overlayfs. It required moving the pipe.Sizer interface
to fs so that overlay could get access.
Fixes#318
PiperOrigin-RevId: 255511125
Addresses obvious typos, in the documentation only.
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/gvisor/pull/443 from Pixep:fix/documentation-spelling 4d0688164eafaf0b3010e5f4824b35d1e7176d65
PiperOrigin-RevId: 255477779
Currently, the overlay dirCache is only used for a single logical use of
getdents. i.e., it is discard when the FD is closed or seeked back to
the beginning.
But the initial work of getting the directory contents can be quite
expensive (particularly sorting large directories), so we should keep it
as long as possible.
This is very similar to the readdirCache in fs/gofer.
Since the upper filesystem does not have to allow caching readdir
entries, the new CacheReaddir MountSourceOperations method controls this
behavior.
This caching should be trivially movable to all Inodes if desired,
though that adds an additional copy step for non-overlay Inodes.
(Overlay Inodes already do the extra copy).
PiperOrigin-RevId: 255477592
The code was wrongly assuming that only read access was
required from the lower overlay when checking for permissions.
This allowed non-writable files to be writable in the overlay.
Fixes#316
PiperOrigin-RevId: 255263686
For files with O_APPEND, a file write operation gets a file size and uses it as
offset to call an inode write operation. This means that all other operations
which can change a file size should be blocked while the write operation doesn't
complete.
PiperOrigin-RevId: 254873771
We don't have the plumbing for btime yet, so that field is left off. The
returned mask indicates that btime is absent.
Fixes#343
PiperOrigin-RevId: 254575752
This allows tasks to have distinct mount namespace, instead of all sharing the
kernel's root mount namespace.
Currently, the only way for a task to get a different mount namespace than the
kernel's root is by explicitly setting a different MountNamespace in
CreateProcessArgs, and nothing does this (yet).
In a follow-up CL, we will set CreateProcessArgs.MountNamespace when creating a
new container inside runsc.
Note that "MountNamespace" is a poor term for this thing. It's more like a
distinct VFS tree. When we get around to adding real mount namespaces, this
will need a better naem.
PiperOrigin-RevId: 254009310
Test fails because it's reading 4KB instead of the
expected 64KB. Changed the test to read pipe buffer
size instead of hardcode and added some logging in
case the reason for failure was not pipe buffer size.
PiperOrigin-RevId: 253916040
sockets, pipes and other non-seekable file descriptors don't
use file.offset, so we don't need to update it.
With this change, we will be able to call file operations
without locking the file.mu mutex. This is already used for
pipes in the splice system call.
PiperOrigin-RevId: 253746644
Parse annotations containing 'gvisor.dev/spec/mount' that gives
hints about how mounts are shared between containers inside a
pod. This information can be used to better inform how to mount
these volumes inside gVisor. For example, a volume that is shared
between containers inside a pod can be bind mounted inside the
sandbox, instead of being two independent mounts.
For now, this information is used to allow the same tmpfs mounts
to be shared between containers which wasn't possible before.
PiperOrigin-RevId: 252704037
Store enough information in the kernel socket table to distinguish
between different types of sockets. Previously we were only storing
the socket family, but this isn't enough to classify sockets. For
example, TCPv4 and UDPv4 sockets are both AF_INET, and ICMP sockets
are SOCK_DGRAM sockets with a particular protocol.
Instead of creating more sub-tables, flatten the socket table and
provide a filtering mechanism based on the socket entry.
Also generate and store a socket entry index ("sl" in linux) which
allows us to output entries in a stable order from procfs.
PiperOrigin-RevId: 252495895
Overlayfs was expecting the parent to exist when bind(2)
was called, which may not be the case. The fix is to copy
the parent directory to the upper layer before binding
the UDS.
There is not good place to add tests for it. Syscall tests
would be ideal, but it's hard to guarantee that the
directory where the socket is created hasn't been touched
before (and thus copied the parent to the upper layer).
Added it to runsc integration tests for now. If it turns
out we have lots of these kind of tests, we can consider
moving them somewhere more appropriate.
PiperOrigin-RevId: 251954156
This is necessary for implementing network diagnostic interfaces like
/proc/net/{tcp,udp,unix} and sock_diag(7).
For pass-through endpoints such as hostinet, we obtain the socket
state from the backend. For netstack, we add explicit tracking of TCP
states.
PiperOrigin-RevId: 251934850
This is required to make the shutdown visible to peers outside the
sandbox.
The readClosed / writeClosed fields were dropped, as they were
preventing a shutdown socket from reading the remainder of queued bytes.
The host syscalls will return the appropriate errors for shutdown.
The control message tests have been split out of socket_unix.cc to make
the (few) remaining tests accessible to testing inherited host UDS,
which don't support sending control messages.
Updates #273
PiperOrigin-RevId: 251763060
We don't actually support core dumps, but some applications want to
get/set dumpability, which still has an effect in procfs.
Lack of support for set-uid binaries or fs creds simplifies things a
bit.
As-is, processes started via CreateProcess (i.e., init and sentryctl
exec) have normal dumpability. I'm a bit torn on whether sentryctl exec
tasks should be dumpable, but at least since they have no parent normal
UID/GID checks should protect them.
PiperOrigin-RevId: 251712714
When pipe is created, a dirent of pipe will be
created and its initial reference is set as 0.
Cause all dirent will only be destroyed when
the reference decreased to -1, so there is already
a 'initial reference' of dirent after it created.
For destroying dirent after all reference released,
the correct way is to drop the 'initial reference'
once someone hold a reference to the dirent, such
as fs.NewFile, otherwise the reference of dirent
will stay 0 all the time, and will cause memory
leak of dirent.
Except pipe, timerfd/eventfd/epoll has the same
problem
Here is a simple case to create memory leak of dirent
for pipe/timerfd/eventfd/epoll in C langange, after
run the case, pprof the runsc process, you will
find lots dirents of pipe/timerfd/eventfd/epoll not
freed:
int main(int argc, char *argv[])
{
int i;
int n;
int pipefd[2];
if (argc != 3) {
printf("Usage: %s epoll|timerfd|eventfd|pipe <iterations>\n", argv[0]);
}
n = strtol(argv[2], NULL, 10);
if (strcmp(argv[1], "epoll") == 0) {
for (i = 0; i < n; ++i)
close(epoll_create(1));
} else if (strcmp(argv[1], "timerfd") == 0) {
for (i = 0; i < n; ++i)
close(timerfd_create(CLOCK_REALTIME, 0));
} else if (strcmp(argv[1], "eventfd") == 0) {
for (i = 0; i < n; ++i)
close(eventfd(0, 0));
} else if (strcmp(argv[1], "pipe") == 0) {
for (i = 0; i < n; ++i)
if (pipe(pipefd) == 0) {
close(pipefd[0]);
close(pipefd[1]);
}
}
printf("%s %s test finished\r\n",argv[1],argv[2]);
return 0;
}
Change-Id: Ia1b8a1fb9142edb00c040e44ec644d007f81f5d2
PiperOrigin-RevId: 251531096
The io.Writer contract requires that Write writes all available
bytes and does not return short writes. This causes errors with
io.Copy, since our own Write interface does not have this same
contract.
PiperOrigin-RevId: 251368730
VmData is the size of private data segments.
It has the same meaning as in Linux.
Change-Id: Iebf1ae85940a810524a6cde9c2e767d4233ddb2a
PiperOrigin-RevId: 250593739
We don't need to model internal interfaces after the system
call interfaces (which are objectively worse and simply use a
flag to distinguish between two logically different operations).
PiperOrigin-RevId: 249916814
Change-Id: I45d02e0ec0be66b782a685b1f305ea027694cab9
sendfile can be called for a big range and it can require significant
amount of time to process it, so we need to handle task interrupts in
this system call.
PiperOrigin-RevId: 249781023
Change-Id: Ifc2ec505d74c06f5ee76f93b8d30d518ec2d4015
Initialized BUILD with license
Mount is still unimplemented and is not meant to be
part of this CL. Rest of the fs interface is implemented.
Referenced the Linux kernel appropriately when needed
PiperOrigin-RevId: 249741997
Change-Id: Id1e4c7c9e68b3f6946da39896fc6a0c3dcd7f98c
Separate MountSource from Mount. This is needed to allow
mounts to be shared by multiple containers within the same
pod.
PiperOrigin-RevId: 249617810
Change-Id: Id2944feb7e4194951f355cbe6d4944ae3c02e468
There no obvious reason to require that BlockSize and StatFS
are MountSource operations. Today they are in INodeOperations,
and they can be moved elsewhere in the future as part of a
normal refactor process.
PiperOrigin-RevId: 249549982
Change-Id: Ib832e02faeaf8253674475df4e385bcc53d780f3
This does not actually implement an efficient splice or sendfile. Rather, it
adds a generic plumbing to the file internals so that this can be added. All
file implementations use the stub fileutil.NoSplice implementation, which
causes sendfile and splice to fall back to an internal copy.
A basic splice system call interface is added, along with a test.
PiperOrigin-RevId: 249335960
Change-Id: Ic5568be2af0a505c19e7aec66d5af2480ab0939b
The backing 9p server must allow named pipe creation, which the runsc
fsgofer currently does not.
There are small changes to the overlay here. GetFile may block when
opening a named pipe, which can cause a deadlock:
1. open(O_RDONLY) -> copyMu.Lock() -> GetFile()
2. open(O_WRONLY) -> copyMu.Lock() -> Deadlock
A named pipe usable for writing must already be on the upper filesystem,
but we are still taking copyMu for write when checking for upper. That
can be changed to a read lock to fix the common case.
However, a named pipe on the lower filesystem would still deadlock in
open(O_WRONLY) when it tries to actually perform copy up (which would
simply return EINVAL). Move the copy up type check before taking copyMu
for write to avoid this.
p9 must be modified, as it was incorrectly removing the file mode when
sending messages on the wire.
PiperOrigin-RevId: 249154033
Change-Id: Id6637130e567b03758130eb6c7cdbc976384b7d6
* Creation of files, directories (and other fs objects) in a directory
should always update ctime.
* Same for removal.
* atime should not be updated on lookup, only readdir.
I've also renamed some misleading functions that update mtime and ctime.
PiperOrigin-RevId: 249115063
Change-Id: I30fa275fa7db96d01aa759ed64628c18bb3a7dc7
There is a lot of redundancy that we can simplify in the stat_times
test. This will make it easier to add new tests. However, the
simplification reveals that cached uattrs on goferfs don't properly
update ctime on rename.
PiperOrigin-RevId: 248773425
Change-Id: I52662728e1e9920981555881f9a85f9ce04041cf
Ayush Ranjan
Ian Gudger
Adin Scannell
Nicolas Lacasse
Fabricio Voznika
Michael Pratt
Andrei Vagin
Rahat Mahmood
Yong He
chris.zn
Neel Natu