NewSCMCredentials previously resolved the specified PID into a thread group with separate calls to ThreadGroupWithID() and PIDNamespacedIDs().
Both of these functions separately take and release the TaskSet lock.
This causes a race condition where between the two function calls, the thread group might get reaped, leading to the panic() being reached.
This commit addresses this issue by moving the thread group resolution/PID namespace map creation into a single critical section.
A regression syscall test is also included.
Reported-by: [email protected]
Previously, scmCredentials stored a *kernel.Task, from which the peer
pid could be looked up when getsockopt() was called with SO_PEERCRED.
However, if the peer had since died, the lookup would fail and the
returned pid would be 0.
Instead, we should store a snapshot of the *pid*, not the Task pointer.
The lookup should happen at open time, not at getsockopt() time.
This does mean that the returned pid may be stale, but this happens on
Linux too, so userspace should know to avoid racy behavior with the
returned PID.
Other things changed:
- Since the cred is a PID, not a TID, use the task group ID instead of
task ID
- Add a test for SO_PEERCRED across a different PID namespace
This is needed so that connectioned endpoint in the transport package can use
this endpoint to implement host FD based binded endpoints.
I had to simplify some other dependencies to make this possible.
- Removed uniqueid's dependency on transport package completely.
- Removed SCMConnectedEndpoint and HostConnectedEndpoint's dependency on
control package so they could be moved to transport. control already depends
on transport.
- scmRights struct from fsimpl/host/control.go had to be moved into transport
so that HostConnectedEndpoint could be implemented. But scmRights.Fill()
could not be moved because it inherently depends on making
vfs.FileDescriptions which depends on vfs which in turn depends on transport.
So now that scmRights -> vfs.FD conversion happens in the syscall package.
PiperOrigin-RevId: 413839350
Change marshal.Marshallable method signatures to return the remaining buffer.
This makes it easier to implement these method manually. Without this, we would
have to manually do buffer shifting which is error prone.
tools/go_marshal/test:benchmark test does not show change in performance.
Additionally fixed some marshalling bugs in fsimpl/fuse.
Updated multiple callpoints to get rid of redundant slice indexing work and
simplified code using this new signature.
Updates #6450
PiperOrigin-RevId: 407857019
Update all instances of the above errors to the faster linuxerr implementation.
With the temporary linuxerr.Equals(), no logical changes are made.
PiperOrigin-RevId: 382306655
Remove three syserror entries duplicated in linuxerr. Because of the
linuxerr.Equals method, this is a mere change of return values from
syserror to linuxerr definitions.
Done with only these three errnos as CLs removing all grow to a significantly
large size.
PiperOrigin-RevId: 382173835
Split usermem package to help remove syserror dependency in go_marshal.
New hostarch package contains code not dependent on syserror.
PiperOrigin-RevId: 365651233
There are surprisingly few syscall tests that run with hostinet. For example
running the following command only returns two results:
`bazel query test/syscalls:all | grep hostnet`
I think as a result, as our control messages evolved, hostinet was left
behind. Update it to support all control messages netstack supports.
This change also updates sentry's control message parsing logic to make it up to
date with all the control messages we support.
PiperOrigin-RevId: 347508892
tcpip.ControlMessages can not contain Linux specific structures which makes it
painful to convert back and forth from Linux to tcpip back to Linux when passing
around control messages in hostinet and raw sockets.
Now we convert to the Linux version of the control message as soon as we are
out of tcpip.
PiperOrigin-RevId: 347027065
Inode number consistency checks are now skipped in save/restore tests for
reasons described in greatest detail in StatTest.StateDoesntChangeAfterRename.
They pass in VFS1 due to the bug described in new test case
SimpleStatTest.DifferentFilesHaveDifferentDeviceInodeNumberPairs.
Fixes#1663
PiperOrigin-RevId: 338776148
Added the ability to get/set the IP_RECVTCLASS socket option on UDP endpoints.
If enabled, traffic class from the incoming Network Header passed as ancillary
data in the ControlMessages.
Adding Get/SetSockOptBool to decrease the overhead of getting/setting simple
options. (This was absorbed in a CL that will be landing before this one).
Test:
* Added unit test to udp_test.go that tests getting/setting as well as
verifying that we receive expected TOS from incoming packet.
* Added a syscall test for verifying getting/setting
* Removed test skip for existing syscall test to enable end to end test.
PiperOrigin-RevId: 295840218
Because the abi will depend on the core types for marshalling (usermem,
context, safemem, safecopy), these need to be flattened from the sentry
directory. These packages contain no sentry-specific details.
PiperOrigin-RevId: 291811289
Added the ability to get/set the IP_RECVTOS socket option on UDP endpoints. If
enabled, TOS from the incoming Network Header passed as ancillary data in the
ControlMessages.
Test:
* Added unit test to udp_test.go that tests getting/setting as well as
verifying that we receive expected TOS from incoming packet.
* Added a syscall test
PiperOrigin-RevId: 287029703
There are two potential ways of sending a TOS byte with outgoing packets:
including a control message in sendmsg, or setting the IP_TOS/IPV6_TCLASS
socket options (for IPV4 and IPV6 respectively). This change lets hostinet
support the former.
PiperOrigin-RevId: 283346737
This involves allowing getsockopt/setsockopt for the corresponding socket
options, as well as allowing hostinet to process control messages received from
the actual recvmsg syscall.
PiperOrigin-RevId: 282851425
This renames FDMap to FDTable and drops the kernel.FD type, which had an entire
package to itself and didn't serve much use (it was freely cast between types,
and served as more of an annoyance than providing any protection.)
Based on BenchmarkFDLookupAndDecRef-12, we can expect 5-10 ns per lookup
operation, and 10-15 ns per concurrent lookup operation of savings.
This also fixes two tangential usage issues with the FDMap. Namely, non-atomic
use of NewFDFrom and associated calls to Remove (that are both racy and fail to
drop the reference on the underlying file.)
PiperOrigin-RevId: 256285890
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
Nothing reads them and they can simply get stale.
Generated with:
$ sed -i "s/licenses(\(.*\)).*/licenses(\1)/" **/BUILD
PiperOrigin-RevId: 231818945
Change-Id: Ibc3f9838546b7e94f13f217060d31f4ada9d4bf0
Ryan El Kochta