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
* Rename syncutil to sync.
* Add aliases to sync types.
* Replace existing usage of standard library sync package.
This will make it easier to swap out synchronization primitives. For example,
this will allow us to use primitives from github.com/sasha-s/go-deadlock to
check for lock ordering violations.
Updates #1472
PiperOrigin-RevId: 289033387
Right now, we need to call ptrace(PTRACE_SYSCALL) and wait() twice to execute
one system call in a stub process. With these changes, we will need to call
ptrace + wait only once.
In addition, this allows to workaround the kernel bug when a stub process
doesn't stop on syscall-exit-stop and starts executing the next system call.
Reported-by: syzbot+37143cafa8dc3b5008ee@syzkaller.appspotmail.com
PiperOrigin-RevId: 288393029
Linux PTRACE_SYSEMU support on arm64 was merged to mainline from
V5.3, and the corresponding support in go also enabled recently.
Since the "syscall" package is locked down from go 1.4, so the ptrace
PTRACE_SYSEMU definition can't be added to package "syscall" on arm64.
According to the golang community, updates required by new systems or
versions should use the corresponding package in the golang.org/x/sys
repository instead(https://golang.org/pkg/syscall/).
Signed-off-by: Haibo Xu <haibo.xu@arm.com>
Change-Id: I2f917bb2be62f990c3e158e2bb99e094ea03f751
Before https://golang.org/cl/173160 syscall.RawSyscall would zero out
the last three register arguments to the system call. That no longer happens.
For system calls that take more than three arguments, use RawSyscall6 to
ensure that we pass zero, not random data, for the additional arguments.
PiperOrigin-RevId: 271062527
Right now, if we can't create a stub process, we will see this error:
panic: unable to activate mm: resource temporarily unavailable
It would be better to know the root cause of this "resource temporarily
unavailable".
PiperOrigin-RevId: 255656831
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
The tracee is stopped early during process exit, when registers are still
available, allowing the tracer to see where the exit occurred, whereas the
normal exit notifi? cation is done after the process is finished exiting.
Without this option, dumpAndPanic fails to get registers.
PiperOrigin-RevId: 254852917
Funcion signatures are not validated during compilation. Since
they are not exported, they can change at any time. The guard
ensures that they are verified at least on every version upgrade.
PiperOrigin-RevId: 250733742
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
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
- 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
The globalPool uses a sync.Once mechanism for initialization,
and no cleanup is strictly required. It's not really feasible
to have the platform implement a full creation -> destruction
cycle (due to the way filters are assumed to be installed), so
drop the FIXME.
PiperOrigin-RevId: 236385278
Change-Id: I98ac660ed58cc688d8a07147d16074a3e8181314
Nothing reads them and they can simply get stale.
Generated with:
$ sed -i "s/licenses(\(.*\)).*/licenses(\1)/" **/BUILD
PiperOrigin-RevId: 231818945
Change-Id: Ibc3f9838546b7e94f13f217060d31f4ada9d4bf0
arch_prctl already verified that the new FS_BASE was canonical, but
Task.Clone did not. Centralize these checks in the arch packages.
Failure to validate could cause an error in PTRACE_SET_REGS when we try
to switch to the app.
PiperOrigin-RevId: 224862398
Change-Id: Iefe63b3f9aa6c4810326b8936e501be3ec407f14
RET_KILL_THREAD doesn't work well for Go because it will
kill only the offending thread and leave the process hanging.
RET_TRAP can be masked out and it's not guaranteed to kill
the process. RET_KILL_PROCESS is available since 4.14.
For older kernel, continue to use RET_TRAP as this is the
best option (likely to kill process, easy to debug).
PiperOrigin-RevId: 222357867
Change-Id: Icc1d7d731274b16c2125b7a1ba4f7883fbdb2cbd
Pseudoterminal job control signals are meant to be received and handled by the
sandbox process, but if the ptrace stubs are running in the same process group,
they will receive the signals as well and inject then into the sentry kernel.
This can result in duplicate signals being delivered (often to the wrong
process), or a sentry panic if the ptrace stub is inactive.
This CL makes the ptrace stub run in a new session.
PiperOrigin-RevId: 218536851
Change-Id: Ie593c5687439bbfbf690ada3b2197ea71ed60a0e
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
This is a defense-in-depth measure. If the sentry is compromised, this prevents
system call injection to the stubs. There is some complexity with respect to
ptrace and seccomp interactions, so this protection is not really available
for kernel versions < 4.8; this is detected dynamically.
Note that this also solves the vsyscall emulation issue by adding in
appropriate trapping for those system calls. It does mean that a compromised
sentry could theoretically inject these into the stub (ignoring the trap and
resume, thereby allowing execution), but they are harmless.
PiperOrigin-RevId: 216647581
Change-Id: Id06c232cbac1f9489b1803ec97f83097fcba8eb8
runApp.execute -> Task.SendSignal -> sendSignalLocked -> sendSignalTimerLocked
-> pendingSignals.enqueue assumes that it owns the arch.SignalInfo returned
from platform.Context.Switch.
On the other hand, ptrace.context.Switch assumes that it owns the returned
SignalInfo and can safely reuse it on the next call to Switch. The KVM platform
always returns a unique SignalInfo.
This becomes a problem when the returned signal is not immediately delivered,
allowing a future signal in Switch to change the previous pending SignalInfo.
This is noticeable in #38 when external SIGINTs are delivered from the PTY
slave FD. Note that the ptrace stubs are in the same process group as the
sentry, so they are eligible to receive the PTY signals. This should probably
change, but is not the only possible cause of this bug.
Updates #38
Original change by newmanwang <wcs1011@gmail.com>, updated by Michael Pratt
<mpratt@google.com>.
Change-Id: I5383840272309df70a29f67b25e8221f933622cd
PiperOrigin-RevId: 213071072
We have been unnecessarily creating too many savable types implicitly.
PiperOrigin-RevId: 206334201
Change-Id: Idc5a3a14bfb7ee125c4f2bb2b1c53164e46f29a8
If the child stubs are killed by any unmaskable signal (e.g. SIGKILL), then
the parent process will similarly be killed, resulting in the death of all
other stubs.
The effect of this is that if the OOM killer selects and kills a stub, the
effect is the same as though the OOM killer selected and killed the sentry.
PiperOrigin-RevId: 202219984
Change-Id: I0b638ce7e59e0a0f4d5cde12a7d05242673049d7
Adin Scannell
Ian Gudger
Andrei Vagin
Haibo Xu
Michael Pratt
gVisor bot
Jamie Liu
Fabricio Voznika
Nicolas Lacasse
newmanwang
Zhaozhong Ni
Googler