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
And stop storing the Filesystem in the MountSource.
This allows us to decouple the MountSource filesystem type from the name of the
filesystem.
PiperOrigin-RevId: 247292982
Change-Id: I49cbcce3c17883b7aa918ba76203dfd6d1b03cc8
This feature allows MemoryFile to delay eviction of "optional"
allocations, such as unused cached file pages.
Note that this incidentally makes CachingInodeOperations writeback
asynchronous, in the sense that it doesn't occur until eviction; this is
necessary because between when a cached page becomes evictable and when
it's evicted, file writes (via CachingInodeOperations.Write) may dirty
the page.
As currently implemented, this feature won't meaningfully impact
steady-state memory usage or caching; the reclaimer goroutine will
schedule eviction as soon as it runs out of other work to do. Future CLs
increase caching by adding constraints on when eviction is scheduled.
PiperOrigin-RevId: 246014822
Change-Id: Ia85feb25a2de92a48359eb84434b6ec6f9bea2cb
Based on the guidelines at
https://opensource.google.com/docs/releasing/authors/.
1. $ rg -l "Google LLC" | xargs sed -i 's/Google LLC.*/The gVisor Authors./'
2. Manual fixup of "Google Inc" references.
3. Add AUTHORS file. Authors may request to be added to this file.
4. Point netstack AUTHORS to gVisor AUTHORS. Drop CONTRIBUTORS.
Fixes#209
PiperOrigin-RevId: 245823212
Change-Id: I64530b24ad021a7d683137459cafc510f5ee1de9
Maximum filename length is filesystem-dependent, and obtained via
statfs::f_namelen. This limit is usually 255 bytes (NAME_MAX), but not
always. For example, VFAT supports filenames of up to 255... UCS-2
characters, which Linux conservatively takes to mean UTF-8-encoded
bytes: fs/fat/inode.c:fat_statfs(), FAT_LFN_LEN * NLS_MAX_CHARSET_SIZE.
As a result, Linux's VFS does not enforce NAME_MAX:
$ rg --maxdepth=1 '\WNAME_MAX\W' fs/ include/linux/
fs/libfs.c
38: buf->f_namelen = NAME_MAX;
64: if (dentry->d_name.len > NAME_MAX)
include/linux/relay.h
74: char base_filename[NAME_MAX]; /* saved base filename */
include/linux/fscrypt.h
149: * filenames up to NAME_MAX bytes, since base64 encoding expands the length.
include/linux/exportfs.h
176: * understanding that it is already pointing to a a %NAME_MAX+1 sized
Remove this check from core VFS, and add it to ramfs (and by extension
tmpfs), where it is actually applicable:
mm/shmem.c:shmem_dir_inode_operations.lookup == simple_lookup *does*
enforce NAME_MAX.
PiperOrigin-RevId: 245324748
Change-Id: I17567c4324bfd60e31746a5270096e75db963fac
FD limit and file size limit is read from the host, instead
of using hard-coded defaults, given that they effect the sandbox
process. Also limit the direct cache to use no more than half
if the available FDs.
PiperOrigin-RevId: 244050323
Change-Id: I787ad0fdf07c49d589e51aebfeae477324fe26e6
RootFromContext can return a dirent with reference taken, or nil. We must call
DecRef if (and only if) a real dirent is returned.
PiperOrigin-RevId: 242965515
Change-Id: Ie2b7b4cb19ee09b6ccf788b71f3fd7efcdf35a11
DirentCache is already a savable type, and it ensures that it is empty at the
point of Save. There is no reason not to save it along with the MountSource.
This did uncover an issue where not all MountSources were properly flushed
before Save. If a mount point has an open file and is then unmounted, we save
the MountSource without flushing it first. This CL also fixes that by flushing
all MountSources for all open FDs on Save.
PiperOrigin-RevId: 242906637
Change-Id: I3acd9d52b6ce6b8c989f835a408016cb3e67018f
We construct a ramfs tree of "scaffolding" directories for all mount points, so
that a directory exists that each mount point can be mounted over.
We were creating these directories without write permissions, which meant that
they were not wribable even when underlayed under a writable filesystem. They
should be writable.
PiperOrigin-RevId: 242507789
Change-Id: I86645e35417560d862442ff5962da211dbe9b731
Strings are a better fit for this usage because they are immutable in Go, and
can contain arbitrary bytes. It also allows us to avoid casting bytes to string
(and the associated allocation) in the hot path when checking for overlay
whiteouts.
PiperOrigin-RevId: 242208856
Change-Id: I7699ae6302492eca71787dd0b72e0a5a217a3db2
Dirent.exists() is called in Create to check whether a child with the given
name already exists.
Dirent.exists() calls walk(), and before this CL allowed walk() to drop d.mu
while calling d.Inode.Lookup. During this existence check, a racing Rename()
can acquire d.mu and create a new child of the dirent with the same name.
(Note that the source and destination of the rename must be in the same
directory, otherwise renameMu will be taken preventing the race.) In this
case, d.exists() can return false, even though a child with the same name
actually does exist.
This CL changes d.exists() so that it does not release d.mu while walking, thus
preventing the race with Rename.
It also adds comments noting that lockForRename may not take renameMu if the
source and destination are in the same directory, as this is a bit surprising
(at least it was to me).
PiperOrigin-RevId: 241842579
Change-Id: I56524870e39dfcd18cab82054eb3088846c34813
The previous implementation revolved around runes instead of bytes, which caused
weird behavior when converting between the two. For example, peekRune would read
the byte 0xff from a buffer, convert it to a rune, then return it. As rune is an
alias of int32, 0xff was 0-padded to int32(255), which is the hex code point for
?. However, peekRune also returned the length of the byte (1). When calling
utf8.EncodeRune, we only allocated 1 byte, but tried the write the 2-byte
character ?.
tl;dr: I apparently didn't understand runes when I wrote this.
PiperOrigin-RevId: 241789081
Change-Id: I14c788af4d9754973137801500ef6af7ab8a8727
Also makes the safemem reading and writing inline, as it makes it easier to see
what locks are held.
PiperOrigin-RevId: 241775201
Change-Id: Ib1072f246773ef2d08b5b9a042eb7e9e0284175c
Also remove comments in InodeOperations that required that implementation of
some Create* operations ensure that the name does not already exist, since
these checks are all centralized in the Dirent.
PiperOrigin-RevId: 241637335
Change-Id: Id098dc6063ff7c38347af29d1369075ad1e89a58
ilist:generic_list works faster (cl/240185278) and
the code looks cleaner without type casting.
PiperOrigin-RevId: 241381175
Change-Id: I8487ab1d73637b3e9733c253c56dce9e79f0d35f
- Document fsutil.CachedFileObject.FD() requirements on access
permissions, and change gofer.inodeFileState.FD() to honor them.
Fixes#147.
- Combine gofer.inodeFileState.readonly and
gofer.inodeFileState.readthrough, and simplify handle caching logic.
- Inline gofer.cachePolicy.cacheHandles into
gofer.inodeFileState.setSharedHandles, because users with access to
gofer.inodeFileState don't necessarily have access to the fs.Inode
(predictably, this is a save/restore problem).
Before this CL:
$ docker run --runtime=runsc-d -v $(pwd)/gvisor/repro:/root/repro -it ubuntu bash
root@34d51017ed67:/# /root/repro/runsc-b147
mmap: 0x7f3c01e45000
Segmentation fault
After this CL:
$ docker run --runtime=runsc-d -v $(pwd)/gvisor/repro:/root/repro -it ubuntu bash
root@d3c3cb56bbf9:/# /root/repro/runsc-b147
mmap: 0x7f78987ec000
o
PiperOrigin-RevId: 240818413
Change-Id: I49e1d4a81a0cb9177832b0a9f31a10da722a896b
The start time is the number of clock ticks between the boot time and
application start time.
PiperOrigin-RevId: 240619475
Change-Id: Ic8bd7a73e36627ed563988864b0c551c052492a5
Memfds are simply anonymous tmpfs files with no associated
mounts. Also implementing file seals, which Linux only implements for
memfds at the moment.
PiperOrigin-RevId: 240450031
Change-Id: I31de78b950101ae8d7a13d0e93fe52d98ea06f2f
MM.insertPMAsLocked() passes vma.maxPerms to memmap.Mappable.Translate
(although it unsets AccessType.Write if the vma is private). This
somewhat simplifies handling of pmas, since it means only COW-break
needs to replace existing pmas. However, it also means that a MAP_SHARED
mapping of a file opened O_RDWR dirties the file, regardless of the
mapping's permissions and whether or not the mapping is ever actually
written to with I/O that ignores permissions (e.g.
ptrace(PTRACE_POKEDATA)).
To fix this:
- Change the pma-getting path to request only the permissions that are
required for the calling access.
- Change memmap.Mappable.Translate to take requested permissions, and
return allowed permissions. This preserves the existing behavior in the
common cases where the memmap.Mappable isn't
fsutil.CachingInodeOperations and doesn't care if the translated
platform.File pages are written to.
- Change the MM.getPMAsLocked path to support permission upgrading of
pmas outside of copy-on-write.
PiperOrigin-RevId: 240196979
Change-Id: Ie0147c62c1fbc409467a6fa16269a413f3d7d571
Also, changing queue.writeBuf from a buffer.Bytes to a [][]byte should reduce
copying and reallocating of slices.
PiperOrigin-RevId: 239713547
Change-Id: I6ee5ff19c3ee2662f1af5749cae7b73db0569e96
In the case of a rename replacing an existing destination inode, ramfs
Rename failed to first remove the replaced inode. This caused:
1. A leak of a reference to the inode (making it live indefinitely).
2. For directories, a leak of the replaced directory's .. link to the
parent. This would cause the parent's link count to incorrectly
increase.
(2) is much simpler to test than (1), so that's what I've done.
agentfs has a similar bug with link count only, so the Dirent layer
informs the Inode if this is a replacing rename.
Fixes#133
PiperOrigin-RevId: 239105698
Change-Id: I4450af2462d8ae3339def812287213d2cbeebde0
This is in preparation for improved page cache reclaim, which requires
greater integration between the page cache and page allocator.
PiperOrigin-RevId: 238444706
Change-Id: Id24141b3678d96c7d7dc24baddd9be555bffafe4
p9.Twalk.handle() with a non-empty path also stats the walked-to path
anyway, so the preceding GetAttr is completely wasted.
PiperOrigin-RevId: 238440645
Change-Id: I7fbc7536f46b8157639d0d1f491e6aaa9ab688a3
- Redefine some memmap.Mappable, platform.File, and platform.Memory
semantics in terms of File reference counts (no functional change).
- Make AddressSpace.MapFile take a platform.File instead of a raw FD,
and replace platform.File.MapInto with platform.File.FD. This allows
kvm.AddressSpace.MapFile to always use platform.File.MapInternal instead
of maintaining its own (redundant) cache of file mappings in the sentry
address space.
PiperOrigin-RevId: 238044504
Change-Id: Ib73a11e4275c0da0126d0194aa6c6017a9cef64f
Current procfs has some bugs. After executing ls twice, many dirs come
out with same name like "1" or ".". Files like "cpuinfo" disappear.
Here variable names is a slice with cap() > len(). Sort after appending
to it will not alloc a new space and impact orignal slice. Same to m.
Signed-off-by: Ruidong Cao <crdfrank@gmail.com>
Change-Id: I83e5cd1c7968c6fe28c35ea4fee497488d4f9eef
PiperOrigin-RevId: 236222270
In addition to simplifying the implementation, this fixes two bugs:
- seqfile.NewSeqFile unconditionally creates an inode with mode 0444,
but {uid,gid}_map have mode 0644.
- idMapSeqFile.Write implements fs.FileOperations.Write ... but it
doesn't implement any other fs.FileOperations methods and is never
used as fs.FileOperations. idMapSeqFile.GetFile() =>
seqfile.SeqFile.GetFile() uses seqfile.seqFileOperations instead,
which rejects all writes.
PiperOrigin-RevId: 234638212
Change-Id: I4568f741ab07929273a009d7e468c8205a8541bc
If a background process tries to read from a TTY, linux sends it a SIGTTIN
unless the signal is blocked or ignored, or the process group is an orphan, in
which case the syscall returns EIO.
See drivers/tty/n_tty.c:n_tty_read()=>job_control().
If a background process tries to write a TTY, set the termios, or set the
foreground process group, linux then sends a SIGTTOU. If the signal is ignored
or blocked, linux allows the write. If the process group is an orphan, the
syscall returns EIO.
See drivers/tty/tty_io.c:tty_check_change().
PiperOrigin-RevId: 234044367
Change-Id: I009461352ac4f3f11c5d42c43ac36bb0caa580f9
fs/gofer/inodeOperations.Release does some asynchronous work. Previously it
was calling fs.Async with an anonymous function, which caused the function to
be allocated on the heap. Because Release is relatively hot, this results in a
lot of small allocations and increased GC pressure, noticeable in perf profiles.
This CL adds a new function, AsyncWithContext, which is just like Async, but
passes a context to the async function. It avoids the need for an extra
anonymous function in fs/gofer/inodeOperations.Release. The Async function
itself still requires a single anonymous function.
PiperOrigin-RevId: 233141763
Change-Id: I1dce4a883a7be9a8a5b884db01e654655f16d19c
- Change proc to return envp on overwrite of argv with limitations from
upstream.
- Add unit tests
- Change layout of argv/envp on the stack so that end of argv is contiguous with
beginning of envp.
PiperOrigin-RevId: 232506107
Change-Id: I993880499ab2c1220f6dc456a922235c49304dec
Dirty should be set only when the attribute is changed in the cache
only. Instances where the change was also sent to the backing file
doesn't need to dirty the attribute.
Also remove size update during WriteOut as writing dirty page would
naturaly grow the file if needed.
RELNOTES: relnotes is needed for the parent CL.
PiperOrigin-RevId: 232068978
Change-Id: I00ba54693a2c7adc06efa9e030faf8f2e8e7f188
This changed required making fsutil.HostMappable use
a backing file to ensure the correct FD would be used
for read/write operations.
RELNOTES: relnotes is needed for the parent CL.
PiperOrigin-RevId: 231836164
Change-Id: I8ae9639715529874ea7d80a65e2c711a5b4ce254
Nothing reads them and they can simply get stale.
Generated with:
$ sed -i "s/licenses(\(.*\)).*/licenses(\1)/" **/BUILD
PiperOrigin-RevId: 231818945
Change-Id: Ibc3f9838546b7e94f13f217060d31f4ada9d4bf0
We were modifying InodeSimpleAttributes.Unstable.AccessTime without holding
the necessary lock. Luckily for us, InodeSimpleAttributes already has a
NotifyAccess method that will do the update while holding the lock.
In addition, we were holding dfo.dir.mu.Lock while setting AccessTime, which
is unnecessary, so that lock has been removed.
PiperOrigin-RevId: 231278447
Change-Id: I81ed6d3dbc0b18e3f90c1df5e5a9c06132761769
It never actually should have applied to environ (the relevant change in
Linux 4.2 is c2c0bb44620d "proc: fix PAGE_SIZE limit of
/proc/$PID/cmdline"), and we claim to be Linux 4.4 now anyway.
PiperOrigin-RevId: 231250661
Change-Id: I37f9c4280a533d1bcb3eebb7803373ac3c7b9f15
When file size changes outside the sandbox, page cache was not
refreshing file size which is required for cacheRemoteRevalidating.
In fact, cacheRemoteRevalidating should be skipping the cache
completely since it's not really benefiting from it. The cache is
cache is already bypassed for unstable attributes (see
cachePolicy.cacheUAttrs). And althought the cache is called to
map pages, they will always miss the cache and map directly from
the host.
Created a HostMappable struct that maps directly to the host and
use it for files with cacheRemoteRevalidating.
Closes#124
PiperOrigin-RevId: 230998440
Change-Id: Ic5f632eabe33b47241e05e98c95e9b2090ae08fc
Most of the entries are stubbed out at the moment, but even those were
only displayed if IPv6 support was enabled. The entries should be
displayed with IPv4-support only, and with only loopback devices.
PiperOrigin-RevId: 229946441
Change-Id: I18afaa3af386322787f91bf9d168ab66c01d5a4c
More helper structs have been added to the fsutil package to make it easier to
implement fs.InodeOperations and fs.FileOperations.
PiperOrigin-RevId: 229305982
Change-Id: Ib6f8d3862f4216745116857913dbfa351530223b
overlayFileOperations.Readdir was holding overlay.copyMu while calling
DirentReaddir, which then attempts to take take the corresponding Dirent.mu,
causing a lock order violation. (See lock order documentation in
fs/copy_up.go.)
We only actually need to hold copyMu during readdirEntries(), so holding the
lock is moved in there, thus avoiding the lock order violation.
A new lock was added to protect overlayFileOperations.dirCache. We were
inadvertently relying on copyMu to protect this. There is no reason it should
not have its own lock.
PiperOrigin-RevId: 228542473
Change-Id: I03c3a368c8cbc0b5a79d50cc486fc94adaddc1c2
epoll_wait acquires EventPoll.listsMu (in EventPoll.ReadEvents) and
then calls Inotify.Readiness which tries to acquire Inotify.evMu.
getdents acquires Inotify.evMu (in Inotify.queueEvent) and then calls
readyCallback.Callback which tries to acquire EventPoll.listsMu.
The fix is to release Inotify.evMu before calling Queue.Notify. Queue
is thread-safe and doesn't require Inotify.evMu to be held.
Closes#121
PiperOrigin-RevId: 227066695
Change-Id: Id29364bb940d1727f33a5dff9a3c52f390c15761
The code that matches the event being published with events watchers
was wronly matching all watchers in case any of the control event bits
were set.
Issue #121
PiperOrigin-RevId: 226521230
Change-Id: Ie2c42bc4366faaf59fbf80a74e9297499bd93f9e
We must wait for all lazy resources to be released before closing the rootFile.
PiperOrigin-RevId: 226419499
Change-Id: I1d4d961a92b3816e02690cf3eaf0a88944d730cc
The old overlayBoundEndpoint assumed that the lower is not an overlay. It
should check if the lower is an overlay and handle that case.
PiperOrigin-RevId: 225882303
Change-Id: I60660c587d91db2826e0719da0983ec8ad024cb8
Platform objects are not savable, storing references to them in
filesystem datastructures would cause save to fail if someone actually
passed in a Platform.
Current implementations work because everywhere a Platform is
expected, we currently pass in a Kernel object which embeds Platform
and thus satisfies the interface.
Eliminate this indirection and save pointers to Kernel directly.
PiperOrigin-RevId: 225288336
Change-Id: Ica399ff43f425e15bc150a0d7102196c3d54a2ab
MSG_WAITALL requests that recv family calls do not perform short reads. It only
has an effect for SOCK_STREAM sockets, other types ignore it.
PiperOrigin-RevId: 224918540
Change-Id: Id97fbf972f1f7cbd4e08eec0138f8cbdf1c94fe7
By Walking before checking that the directory is writable and
executable, MayDelete may return the Walk error (e.g., ENOENT) which
would normally be masked by a permission error (EACCES).
PiperOrigin-RevId: 224222453
Change-Id: I108a7f730e6bdaa7f277eaddb776267c00805475
The number of symbolic links that are allowed to be followed
are for a full path and not just a chain of symbolic links.
PiperOrigin-RevId: 224047321
Change-Id: I5e3c4caf66a93c17eeddcc7f046d1e8bb9434a40
Replaces the WaitGroup with a RWMutex. Calls to Async hold the mutex for
reading, while AsyncBarrier takes the lock for writing. This ensures that all
executing Async work finishes before AsyncBarrier returns.
Also pushes the Async() call from Inode.Release into
gofer/InodeOperations.Release(). This removes a recursive Async call which
should not have been allowed in the first place. The gofer Release call is the
slow one (since it may make RPCs to the gofer), so putting the Async call there
makes sense.
PiperOrigin-RevId: 223093067
Change-Id: I116da7b20fce5ebab8d99c2ab0f27db7c89d890e
Create syscall stubs for missing syscalls upto Linux 4.4 and advertise
a kernel version of 4.4.
PiperOrigin-RevId: 220667680
Change-Id: Idbdccde538faabf16debc22f492dd053a8af0ba7
https://github.com/containerd/containerd/blob/master/oci/spec.go#L206, the mode=755
didn't match the pattern modeRegexp = regexp.MustCompile("0[0-7][0-7][0-7]").
Closes#112
Signed-off-by: Juan <xionghuan.cn@gmail.com>
Change-Id: I469e0a68160a1278e34c9e1dbe4b7784c6f97e5a
PiperOrigin-RevId: 219672525
Previously this code used the tcpip error space. Since it is no longer part of
netstack, it can use the sentry's error space (except for a few cases where
there is still some shared code. This reduces the number of error space
conversions required for hot Unix socket operations.
PiperOrigin-RevId: 218541611
Change-Id: I3d13047006a8245b5dfda73364d37b8a453784bb
This change also adds extensive testing to the p9 package via mocks. The sanity
checks and type checks are moved from the gofer into the core package, where
they can be more easily validated.
PiperOrigin-RevId: 218296768
Change-Id: I4fc3c326e7bf1e0e140a454cbacbcc6fd617ab55
Added events for *ctl syscalls that may have multiple different commands.
For runsc, each syscall event is only logged once. For *ctl syscalls, use
the cmd as identifier, not only the syscall number.
PiperOrigin-RevId: 218015941
Change-Id: Ie3c19131ae36124861e9b492a7dbe1765d9e5e59
* Integrate recvMsg and sendMsg functions into Recv and Send respectively as
they are no longer shared.
* Clean up partial read/write error handling code.
* Re-order code to make sense given that there is no longer a host.endpoint
type.
PiperOrigin-RevId: 217255072
Change-Id: Ib43fe9286452f813b8309d969be11f5fa40694cd
host.endpoint contained duplicated logic from the sockerpair implementation and
host.ConnectedEndpoint. Remove host.endpoint in favor of a
host.ConnectedEndpoint wrapped in a socketpair end.
PiperOrigin-RevId: 217240096
Change-Id: I4a3d51e3fe82bdf30e2d0152458b8499ab4c987c
- Change Dirent.Busy => Dirent.isMountPoint. The function body is unchanged,
and it is no longer exported.
- fs.MayDelete now checks that the victim is not the process root. This aligns
with Linux's namei.c:may_delete().
- Fix "is-ancestor" checks to actually compare all ancestors, not just the
parents.
- Fix handling of paths that end in dots, which are handled differently in
Rename vs. Unlink.
PiperOrigin-RevId: 217239274
Change-Id: I7a0eb768e70a1b2915017ce54f7f95cbf8edf1fb
Currently, in the face of FileMem fragmentation and a large sendmsg or
recvmsg call, host sockets may pass > 1024 iovecs to the host, which
will immediately cause the host to return EMSGSIZE.
When we detect this case, use a single intermediate buffer to pass to
the kernel, copying to/from the src/dst buffer.
To avoid creating unbounded intermediate buffers, enforce message size
checks and truncation w.r.t. the send buffer size. The same
functionality is added to netstack unix sockets for feature parity.
PiperOrigin-RevId: 216590198
Change-Id: I719a32e71c7b1098d5097f35e6daf7dd5190eff7
Terminal support in runsc relies on host tty file descriptors that are imported
into the sandbox. Application tty ioctls are sent directly to the host fd.
However, those host tty ioctls are associated in the host kernel with a host
process (in this case runsc), and the host kernel intercepts job control
characters like ^C and send signals to the host process. Thus, typing ^C into a
"runsc exec" shell will send a SIGINT to the runsc process.
This change makes "runsc exec" handle all signals, and forward them into the
sandbox via the "ContainerSignal" urpc method. Since the "runsc exec" is
associated with a particular container process in the sandbox, the signal must
be associated with the same container process.
One big difficulty is that the signal should not necessarily be sent to the
sandbox process started by "exec", but instead must be sent to the foreground
process group for the tty. For example, we may exec "bash", and from bash call
"sleep 100". A ^C at this point should SIGINT sleep, not bash.
To handle this, tty files inside the sandbox must keep track of their
foreground process group, which is set/get via ioctls. When an incoming
ContainerSignal urpc comes in, we look up the foreground process group via the
tty file. Unfortunately, this means we have to expose and cache the tty file in
the Loader.
Note that "runsc exec" now handles signals properly, but "runs run" does not.
That will come in a later CL, as this one is complex enough already.
Example:
root@:/usr/local/apache2# sleep 100
^C
root@:/usr/local/apache2# sleep 100
^Z
[1]+ Stopped sleep 100
root@:/usr/local/apache2# fg
sleep 100
^C
root@:/usr/local/apache2#
PiperOrigin-RevId: 215334554
Change-Id: I53cdce39653027908510a5ba8d08c49f9cf24f39
host.endpoint already has the check, but it is missing from
host.ConnectedEndpoint.
PiperOrigin-RevId: 214962762
Change-Id: I88bb13a5c5871775e4e7bf2608433df8a3d348e6
We already forward TCSETS and TCSETSW. TCSETSF is roughly equivalent but
discards pending input.
The filters were relaxed to allow host ioctls with TCSETSF argument.
This fixes programs like "passwd" that prevent user input from being displayed
on the terminal.
Before:
root@b8a0240fc836:/# passwd
Enter new UNIX password: 123
Retype new UNIX password: 123
passwd: password updated successfully
After:
root@ae6f5dabe402:/# passwd
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
PiperOrigin-RevId: 214869788
Change-Id: I31b4d1373c1388f7b51d0f2f45ce40aa8e8b0b58
If we have an overlay file whose corresponding Dirent is frozen, then we should
not bother calling Readdir on the upper or lower files, since DirentReaddir
will calculate children based on the frozen Dirent tree.
A test was added that fails without this change.
PiperOrigin-RevId: 213531215
Change-Id: I4d6c98f1416541a476a34418f664ba58f936a81d
Linux permits hard-linking if the target is owned by the user OR the target has
Read+Write permission.
PiperOrigin-RevId: 213024613
Change-Id: If642066317b568b99084edd33ee4e8822ec9cbb3
We must use a context.Context with a Root Dirent that corresponds to the
container's chroot. Previously we were using the root context, which does not
have a chroot.
Getting the correct context required refactoring some of the path-lookup code.
We can't lookup the path without a context.Context, which requires
kernel.CreateProcArgs, which we only get inside control.Execute. So we have to
do the path lookup much later than we previously were.
PiperOrigin-RevId: 212064734
Change-Id: I84a5cfadacb21fd9c3ab9c393f7e308a40b9b537
Furthermore, allow for the specification of an ElementMapper. This allows a
single "Element" type to exist on multiple inline lists, and work without
having to embed the entry type.
This is a requisite change for supporting a per-Inode list of Dirents.
PiperOrigin-RevId: 211467497
Change-Id: If2768999b43e03fdaecf8ed15f435fe37518d163
From //pkg/sentry/context/context.go:
// - It is *not safe* to retain a Context passed to a function beyond the scope
// of that function call.
Passing a stored kernel.Task as a context.Context to
fs.FileOwnerFromContext violates this requirement.
PiperOrigin-RevId: 211143021
Change-Id: I4c5b02bd941407be4c9cfdbcbdfe5a26acaec037
dirent.walk() takes renameMu, but is often called with renameMu already held,
which can lead to a deadlock.
Fix this by requiring renameMu to be held for reading when dirent.walk() is
called. This causes walks and existence checks to block while a rename
operation takes place, but that is what we were already trying to enforce by
taking renameMu in walk() anyways.
PiperOrigin-RevId: 210760780
Change-Id: Id61018e6e4adbeac53b9c1b3aa24ab77f75d8a54
dirent.go:Rename() walks to the file being replaced and defers
replaced.DecRef(). After the rename, the reference is dropped, triggering a
writeout and SettAttr call to the gofer. Because of lazyOpenForWrite, the gofer
opens the replaced file BY ITS OLD NAME and calls ftruncate on it.
This CL changes Remove to drop the reference on replaced (and thus trigger
writeout) before the actual rename call.
PiperOrigin-RevId: 210756097
Change-Id: I01ea09a5ee6c2e2d464560362f09943641638e0f
Michael Pratt
Yong He
Andrei Vagin
Nicolas Lacasse
chris.zn
Adin Scannell
Ayush Ranjan
Fabricio Voznika
Neel Natu
Jamie Liu
Ian Gudger
Kevin Krakauer
Shiva Prasanth
Wei Zhang
Googler
Rahat Mahmood
Ruidong Cao
Zach Koopmans
Zhaozhong Ni
Adin Scannell
Brian Geffon
Juan