As sandboxed pointers are now default-enabled when the sandbox is
enabled, it is no longer possible to deactivate the sandbox at runtime.
This CL therefore removes all the logic that was required to support a
sandbox that could be disabled at runtime, moves the initialization of
the sandbox into V8::Initialize, and deprecates V8::InitializeSandbox.
This change also makes the sandbox initialization deterministic if
FLAG_random_seed is supplied.
Bug: v8:10391
Change-Id: Ibd49f7c251b7c58c642f18a551ecc2c391740970
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3762583
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81746}
As sandboxed pointers assume a constant sandbox size (they are
essentially n-bit offsets), it is no longer useful to be able to create
smaller sandboxes. This CL simplifies the sandbox initialization logic
accordingly and adds CHECKS to ensure a fixed-size sandbox is created.
Bug: v8:10391
Change-Id: I6541ab769001e60c0256d3a719f926128a0a20b0
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647684
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81720}
This CL does the following:
- It enables (i.e. allocates and initializes) the per-Isolate
ExternalPointerTable when the sandbox is enabled.
- It refactors the list of external pointer tags to mark them as
"sandboxed" or "unsandboxed". An unsandboxed external pointer has a
null tag.
- It changes V8_SANDBOXED_EXTERNAL_POINTERS to now essentially just
enable sandboxing for all available tags.
- It modifies all low-level external pointer accessors to perform the
ExternalPointerLookup only if the tag is non-zero and otherwise treat
the slot as containing a raw pointer.
This now allows rolling out external pointer sandboxing incrementally
(separately for each external pointer type), which will in turn allow
for more precise performance measurements of the impact of the sandbox.
Note: when an external pointer tag is now marked as sandboxed (and
V8_SANDBOXED_EXTERNAL_POINTERS is not enabled), the underlying slots are
still 64-bits in size. This simplifies the implementation as we would
otherwise need to deal with variably-sized external pointer slots. Local
benchmarking suggests that the benefits from 32-bit external pointer
slots are insignificant on typical benchmarks, so this should be ok.
Drive-by: rename kExternalPointerSize to kExternalPointerSlotSize to
make it more clear what it refers to (the on-heap storage size). Also
delete CodeStubAssembler::InitializeExternalPointerField as it is not
currently used and the implementation is fairly inefficient.
Bug: v8:10391
Change-Id: I7c38729c7e9048d737a1a8ced84749f5b1f7feab
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3736447
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81636}
The ExternalPointerTags are assumed to be compile-time constants in most
cases, so turning them into template parameters enforces that. As
decisions such as whether to use the per-isolate or the shared external
pointer table are encoded into the tag values, forcing those to be
compile-time constants guarantees that the compiler will be able to
inline the correct logic when accessing an external pointer.
With this, there are now two (high-level) ways of accessing external pointer fields from C++: the Read/WriteExternalPointerField methods
which require the ExternalPointerTag to be a template parameter, and the
ExternalPointerSlot class which takes the tag as an argument. The latter
is for example used for snapshot deserialization and by the garbage
collector (more generally, by the ObjectVisitor::VisitExternalPointer
method), where the tag is not a compile-time constant.
Finally, this CL also introduces a new ExternalPointerHandle type which
represents the (opaque) on-heap representation of a reference to an
entry in an ExternalPointerTable when sandboxing is enabled. Making this
its own type makes the code a bit more readable.
Bug: v8:10391
Change-Id: I867b8ce41d15d485f1dc66786f233c710c56afcb
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3720641
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81402}
- Change definition to macro-style to be able to assert that masks/tags
are correct.
- Split definition of shared/non-shared tags.
- Use bit 62 (for now) to indicate tags are shared.
Bug: v8:10391
Change-Id: Ia3ad6294cf5e6fd0c4dc2a328f976f295da762f5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3726009
Reviewed-by: Samuel Groß <saelo@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81400}
The waiter queue node of JS Atomics.Mutex is now stored in the shared
external pointer table.
Bug: v8:12547
Change-Id: I2f4ce1c705d5e710b49872942702f60edf6c4043
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3721696
Reviewed-by: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81380}
To be able to share external strings, we need to share the external
pointer table in sandbox builds.
To avoid branches at runtime all pointers for external strings are
stored in the shared external pointer table.
Bug: v8:12957
Change-Id: Iaa6be7839a2f5e50f80fd58c5b33fb9c6af61057
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695263
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81324}
Previously it was implemented in api.cc, therefore requiring an additional
function call when accessing external pointer fields from embedder code with
the sandbox enabled. Now ReadExternalPointerField can be inlined.
Bug: v8:10391
Change-Id: Ia8cb2df148ac96f979fd3e22989b0ff6177abcec
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3714245
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Samuel Groß <saelo@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81271}
... to avoid additional indirection on every access.
Drive-by: given that AccessorInfo class now has a custom body visitor
it's no longer necessary to encode flags field as Smi.
Bug: v8:12949
Change-Id: I30eabee3cbc5ded2bf3f050dfe22208713a764bf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3701590
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81237}
It should be V8_TARGET_OS_ANDROID instead of V8_OS_ANDROID.
Bug: chromium:1218005
Change-Id: I4b92977c5d8b70ca5023e30a966508965ea9f0fe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3706618
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81175}
Drive-by-fix: Reduce one branch in the type compairison since
JS_OBJECT_TYPE and JS_FIRST_API_INSTANCE_TYPE are adjacent.
Bug: v8:11476
Change-Id: I621ef2df4da2858cb1652276f800ccedba4e3015
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695562
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81051}
https://crrev.com/c/3471854 already disabled the RecordWrite builtin
specifically for incremental marking. Since this didn't regress performance as expected, we can now remove those versions of the
builtin.
This will simplify the barrier implementation a bit, but is also
required for the shared heap write barrier. Unlike the generational barrier, the shared heap barrier can't be elided for map values.
Bug: v8:11708
Change-Id: I44bc6ee79006a5be8c1b593dee7fc30c3b9cfa85
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3683341
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Simon Zünd <szuend@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80966}
This is a reland of commit ea9a1f1cbe
Changes since revert:
- Make the state field uintptr-aligned since arm64 faults on
atomic accesses to non-naturally aligned addresses.
Original change's description:
> [shared-struct] Add Atomics.Mutex
>
> This CL adds a moving GC-safe, JS-exposed mutex behind the
> --harmony-struct flag. It uses a ParkingLot-inspired algorithm and
> each mutex manages its own waiter queue.
>
> For more details, please see the design doc: https://docs.google.com/document/d/1QHkmiTF770GKxtoP-VQ1eKF42MpedLUeqiQPfCqus0Y/edit?usp=sharing
>
> Bug: v8:12547
> Change-Id: Ic58f8750d2e14ecd573173d17d5235a136bedef9
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3595460
> Commit-Queue: Shu-yu Guo <syg@chromium.org>
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Reviewed-by: Adam Klein <adamk@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80789}
Bug: v8:12547
Change-Id: I776cbf6ea860dcc6cb0ac51694a9b584b53d255c
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_mac_arm64_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3673354
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80875}
This CL adds a moving GC-safe, JS-exposed mutex behind the
--harmony-struct flag. It uses a ParkingLot-inspired algorithm and
each mutex manages its own waiter queue.
For more details, please see the design doc: https://docs.google.com/document/d/1QHkmiTF770GKxtoP-VQ1eKF42MpedLUeqiQPfCqus0Y/edit?usp=sharing
Bug: v8:12547
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
Change-Id: Ic58f8750d2e14ecd573173d17d5235a136bedef9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3595460
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80789}
The majority of 64-bit Android devices appear to be using a 40-bit
address space, i.e. 512GB for userspace. Allocating a 256GB sandbox
(plus 2x 32GB guard regions) may take too much of the address space and
cause the creation of other address space reservations (e.g. the cppgc
caged heap), which are created per worker, to fail later on.
In general, we should try to limit the sandbox size to less than 1/4 of
the address space, so this CL shinks the sandbox on Android to 128GB.
Bug: chromium:1327131
Change-Id: Ib48b45506ad6a7a5e15b95115c7642bf62a68fa1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3652783
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80636}
This is more consistent with similar features, for example
V8_ENABLE_WEBASSEMBLY or V8_ENABLE_MAGLEV.
Drive-by: remove V8_SANDBOX_IS_AVAILABLE as it's no longer needed.
Bug: v8:10391
Change-Id: I8658c5b0c331a4c73892737083b2c2f9b8f84056
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3647355
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Samuel Groß <saelo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80530}
Remove PENDING state as handles were always immediately transitioned
into FREE or NEAR_DEATH state.
Bug: v8:12672
Change-Id: I9a9d40b573e862282d41d7a4a3f9c8c8ed21b9e4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3599473
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80119}
.. since they are the same as eager deopts (% an unused counter).
Fixed: v8:12765
Change-Id: I2be6210e476ead4ac6629a49259f28321e965867
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3565717
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Jakob Linke <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79729}
This CL removes:
- Dynamic map checks aka minimorphic property loads (TF support,
builtins).
- "Bailout" deopts (= drop to the interpreter once, but don't
throw out optimized code).
- "EagerWithResume" deopts (= part of dynamic map check
functionality, we call a builtin for the deopt check and deopt
or resume based on the result).
Fixed: v8:12552
Change-Id: I492cf1667e0f54586690b2f72a65ea804224b840
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3401585
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79544}
In text, we should use the properly capitalized "Wasm" instead of
"WASM". In particular for frame output, other frames typically use
CamelCase (like "JsToWasmFrame", "ExitFrame", "InternalFrame"), so Wasm
should do the same.
The "0xa" comment in some assemblers is also outdated, the current tag
we emit for StackFrame::WASM is 0x8 (0x4 shifted by one).
R=jkummerow@chromium.org
Bug: v8:12425
Change-Id: Ic3e00c401b219c28b5424c82efb0f1a9df51690f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3525195
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79498}
This method now handles external pointers in HeapObjects during
serialization by encoding the representation of the external pointer
(sandboxed, raw), the origin (internal, api) and potentially the
external pointer tag. It is currently only used to handle
JSExternalObjects but could, in the future, be extended to handle all
external pointers that need special handling during
serialization/deserialization.
Bug: v8:12700
Change-Id: Ib0747d765ddc632e4ca4ee94521616d0271be0bc
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3521904
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79496}
Instead of implementing ExternalObjects as plain JSObjects with a single
EmbedderDataSlot pointing to a Foreign containing the actual raw
pointer, this CL now creates a new JSExternalObject type that directly
contains the external pointer.
As a side-effect of this refactoring, nullptr values are now no longer
valid for ExternalObjects.
Change-Id: Ic8ff334681c966e823ca70f34dd1efaaa21a0789
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3513234
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79459}
This guarantees that they are smaller than the maximum external pointer
table index when shifted to the right on load.
Bug: v8:10391
Change-Id: I601f37fbb9640ee4b5215958afcc474c5e0eb9af
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3359631
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78873}
When sandboxed external pointers are enabled, external pointers now only
require 32 bits of storage space in a HeapObject. This CL does not shrink
the size of EmbedderDataSlots, which will happen in a follow-up CL.
Bug: v8:10391
Change-Id: I3cf8b68c3b985cf806a45183717f50462a88c281
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3359629
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78754}
The external pointer table is now managed by the GC, which marks entries
that are alive during major GC, then sweeps the table afterwards to free
all dead entries and build a free list from them. For now, only major GCs
are supported, Scavenger GCs do not interact with the external pointer table.
In more detail, garbage collection of the external pointer table works
as follows:
1. The external pointer table now reserves a large region of virtual
address space for its backing buffer and is then never reallocated,
only grown in place until the maximum size is reached.
2. When the GC's marking visitor marks a HeapObject with an external
pointer as alive, it also marks the corresponding external pointer
table entry as alive. This can happen on a background thread.
3. For that, it uses the MSB of each entry in the table to indicate
whether the entry has been marked or not. This works because the MSB
is always cleared during the AND-based type check performed when
accessing an external pointer.
4. After marking, the external pointer table is swept while the mutator
is stopped. This builds an inline, singly-linked freelist of all
newly-dead and previously-free entries.
5. When allocating an entry from the table, the first entry on the
freelist is used. If the freelist is empty, the table grows,
populating the freelist with the new entries.
6. Every newly-allocated entry is marked as alive, and every store to an
existing entry also automatically marks that entry as alive (by also
setting the MSB). This simplifies the design of the table GC with
regards to concurrency (See ExternalPointerTable::Mark).
Bug: v8:10391
Change-Id: I8877fdf5576af3761bde65298951bb09e601bd14
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3359625
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78708}
Report young generation GC statistics to the Recorder API.
These will be used by Blink to populate UMA histograms.
Existing UMA reporting in V8 remains as is for now and will be removed
in a followup.
With this CL, minor mark-compaction statistics are reported as part
of V8.GC.Cycle.*.Young. Also V8.GCScavengeReason is migrated to
V8.GC.Cycle.Reason.Young.
This CL goes together with:
https://chromium-review.googlesource.com/c/chromium/src/+/3320388
Bug: chromium:1154636
Change-Id: Ia1030c80d4bc75ac6e176ed60f838929ddb9b20f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3320430
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78416}
This CL renames a number of things related to the V8 sandbox.
Mainly, what used to be under V8_HEAP_SANDBOX is now under
V8_SANDBOXED_EXTERNAL_POINTERS, while the previous V8 VirtualMemoryCage
is now simply the V8 Sandbox:
V8_VIRTUAL_MEMORY_CAGE => V8_SANDBOX
V8_HEAP_SANDBOX => V8_SANDBOXED_EXTERNAL_POINTERS
V8_CAGED_POINTERS => V8_SANDBOXED_POINTERS
V8VirtualMemoryCage => Sandbox
CagedPointer => SandboxedPointer
fake cage => partially reserved sandbox
src/security => src/sandbox
This naming scheme should simplify things: the sandbox is now the large
region of virtual address space inside which V8 mainly operates and
which should be considered untrusted. Mechanisms like sandboxed pointers
are then used to attempt to prevent escapes from the sandbox (i.e.
corruption of memory outside of it). Furthermore, the new naming scheme
avoids the confusion with the various other "cages" in V8, in
particular, the VirtualMemoryCage class, by dropping that name entirely.
Future sandbox features are developed under their own V8_SANDBOX_X flag,
and will, once final, be merged into V8_SANDBOX. Current future features
are sandboxed external pointers (using the external pointer table), and
sandboxed pointers (pointers guaranteed to point into the sandbox, e.g.
because they are encoded as offsets). This CL then also introduces a new
build flag, v8_enable_sandbox_future, which enables all future features.
Bug: v8:10391
Change-Id: I5174ea8f5ab40fb96a04af10853da735ad775c96
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3322981
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78384}
Rename StringShape::full_representation_tag to
StringShape::representation_and_encoding_tag, since the full
representation tag now includes the shared bit.
There are no users of the new method in this CL; this is split out to
make subsequent shared string CLs smaller.
Bug: v8:12007
Change-Id: Ic4ac0241fd9846241e85b4a094dfee6d201ba42b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3313428
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Patrick Thier <pthier@chromium.org>
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78253}
This CL turns references to ArrayBuffer backing stores from
JSArrayBuffers, JSTypedArrays, and JSDataViews into CagedPointers
when those are enabled.
CagedPointers cannot generally represent nullptr, as NULL usually lies
outside the cage. As such, nullptr backing stores are replaced with a
special empty backing store value, which, in the current implementation,
points to the end of the cage, right in front of the trailing guard
regions. Due to this, it is no longer correct to compare a backing store
pointer against nullptr.
Bug: chromium:1218005
Change-Id: I4a6c7a82aabb4debcb6bb2babe4035ba2da8e79f
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3244419
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78218}
The is_shared bit bumps the number of reserved bits for Strings'
InstanceType from 6 to 7. This has the side effect of shuffling the
InstanceType enum values.
There are no users of this bit yet. This is steps 1-2 from the following
design doc [1], in preparation for sharing internalized and
in-place-internalizable strings.
[1] https://docs.google.com/document/d/1c5i8f2EfKIQygGZ23hNiGxouvRISjUMnJjNsOodj6z0/edit?usp=sharing
Bug: v8:12007
Change-Id: Idf11a6035305f0375b4f824ffd32a64f6b5b043b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3266017
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77831}
A CagedPointer is guaranteed to point into the Virtual Memory Cage and
will for example be used for ArrayBuffer backing stores when the heap
sandbox is enabled. In the current implementation, CagedPointers are
stored as offsets from the cage base, shifted to the left. Because the
cage base address is usually available in a register, accessing a
CagedPointer is very efficient, requiring only an additional shift and
add operation.
Bug: chromium:1218005
Change-Id: Ifc8c088e3862400672051a8c52840514dee2911f
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3123417
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77614}
This function tries to determine the number of virtual address bits
available on the current CPU and with that the maximum size of the
userspace address space. On x64, it can be implemented through CPUID.
The result of this function is now used in two ways: first, it limits
the maximum size of the virtual memory cage, currently to a quarter of
the address space. Second, it influences the placement of fake cages,
which are attempted to be placed into the lower half of the address
space so that they are followed by large amounts of (hopefully) unused
but addressable virtual memory in which pages can be allocated.
Bug: chromium:1218005
Change-Id: I0edc5d241d899f16dbc47492fa1534b6aaa4aa13
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3220348
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77393}
This is a reland of 1ea76c1397
Disabled the failing test on Fuchsia until its PageAllocator
respects allocation hints.
Original change's description:
> Implement a fake virtual memory cage mechanism
>
> On operating systems where reserving virtual address space is expensive,
> notably Windows pre 8.1, it is not possible to create a proper virtual
> memory cage. In order to still be able to reference caged objects
> through offsets from the cage base on these systems, this CL introduces
> a fake cage mechanism. When the fake cage is used, most of the virtual
> memory for the cage is not actually reserved. Instead, the cage's page
> allocator simply relies on hints to the OS to obtain pages inside the
> cage. This does, however, not provide the same security benefits as a
> real cage as unrelated allocations might end up inside the cage.
>
> Bug: chromium:1218005
> Change-Id: Ie5314be23966ed0042a017917b63595481b5e7e3
> Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3217200
> Commit-Queue: Samuel Groß <saelo@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#77367}
Bug: chromium:1218005
Change-Id: I2ed95d121db164679c38085115e8fa92690c057e
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3220151
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77378}
This reverts commit 1ea76c1397.
Reason for revert: The unit test added fails on the Fuchsia bot https://ci.chromium.org/p/v8/builders/ci/V8%20Fuchsia/25976?
Original change's description:
> Implement a fake virtual memory cage mechanism
>
> On operating systems where reserving virtual address space is expensive,
> notably Windows pre 8.1, it is not possible to create a proper virtual
> memory cage. In order to still be able to reference caged objects
> through offsets from the cage base on these systems, this CL introduces
> a fake cage mechanism. When the fake cage is used, most of the virtual
> memory for the cage is not actually reserved. Instead, the cage's page
> allocator simply relies on hints to the OS to obtain pages inside the
> cage. This does, however, not provide the same security benefits as a
> real cage as unrelated allocations might end up inside the cage.
>
> Bug: chromium:1218005
> Change-Id: Ie5314be23966ed0042a017917b63595481b5e7e3
> Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3217200
> Commit-Queue: Samuel Groß <saelo@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#77367}
Bug: chromium:1218005
Change-Id: I541bb9656ab2a6a080c2a30d372226fcc5c95391
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3219086
Auto-Submit: Deepti Gandluri <gdeepti@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Owners-Override: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77368}
On operating systems where reserving virtual address space is expensive,
notably Windows pre 8.1, it is not possible to create a proper virtual
memory cage. In order to still be able to reference caged objects
through offsets from the cage base on these systems, this CL introduces
a fake cage mechanism. When the fake cage is used, most of the virtual
memory for the cage is not actually reserved. Instead, the cage's page
allocator simply relies on hints to the OS to obtain pages inside the
cage. This does, however, not provide the same security benefits as a
real cage as unrelated allocations might end up inside the cage.
Bug: chromium:1218005
Change-Id: Ie5314be23966ed0042a017917b63595481b5e7e3
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng,v8_linux_arm64_sim_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3217200
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77367}
At least for the initial rollout, we will gracefully handle cage
reservation failures by shrinking the size of the cage until the
reservation succeeds or the size drops below the mimimum cage size. This
will allow collecting statistics on how often cage reservation failures
occur in practice for different cage sizes, which will in turn influence
the decision on how to handle them in the future.
Bug: chromium:1218005
Change-Id: Ica58951ba51ac01bc2c387b34dfc8d9051ed4d75
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3168347
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76948}
.. for more efficient access to builtins from generated code.
Root-relative accesses tend to be faster and produce more compact
code when the root-relative offset is small. IsolateData contains
a few large tables (roots, external references, builtins), resulting
in very large offsets in general.
This CL starts by splitting the builtin table into tiers: tier 0
is a minimal set of perf-critical builtins that should be cheap to
access. The offset to tier 0 builtins is guaranteed to be small.
The full builtin table also remains in IsolateData for occasions in
which we need to lookup builtins by index.
In future work, we can also split external references and roots into
tiers.
On x64, this reduces deopt exit sizes from 7 to 4 bytes and from 12
to 9 bytes (dynamic map checks / EagerWithResume deopts).
Bug: v8:12203,v8:8661
Change-Id: I5a9ed22b0e00682aca1abcf15892ae1458dbdd70
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3162142
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76947}
Instead of explicitely splitting the cage into two separate regions, we
now just create a single BoundedPageAllocator to manage the entire
address range of the cage, then allocate the first 4GB for the pointer
compression cage.
Bug: chromium:1218005
Change-Id: I02c53ca8b6dda9074ae6caccc74c32bd6271d4d2
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3162044
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76900}
Refactor TryCopyAndConvertArrayToCppBuffer to avoid using a CTypeInfo*
pointer as template argument. Use instead a uint32 encoded value
sufficient to reconstruct the CTypeInfo.
Bug: v8:11739
Change-Id: I74052e59b3fa5ebed00cdb938504ba1947d959d7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3138832
Commit-Queue: Paolo Severini <paolosev@microsoft.com>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76887}
In a follow-up CL, the backing stores will, when the sandbox is enabled,
be referenced from V8 objects through offsets rather than raw pointers.
For that to work, all backing stores must be located inside the virtual
memory cage. This CL prepares for that.
Bug: chromium:1218005
Change-Id: Ibb989626ed7094bd4f02ca15464539f4e2bda90f
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3114136
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76486}
ArrayBuffer backing stores will instead use the virtual memory cage and
be referenced through offsets rather than pointers when the sandbox is
enabled. This will be implemented in an independent CL.
Bug: v8:10391
Change-Id: Icc9781003e53c76dbbf4c84ee165151e4182da4b
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3086458
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76348}
When this is enabled, v8 reserves a large region of virtual address
space during initialization, at the start of which it will place its 4GB
pointer compression cage. The remainder of the cage is used to store
ArrayBuffer backing stores and WASM memory buffers. This will later
allow referencing these buffers from inside V8 through offsets from the
cage base rather than through raw pointers.
Bug: chromium:1218005
Change-Id: I300094b07f64985217104b14c320cc019f8438af
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3010195
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Samuel Groß <saelo@google.com>
Cr-Commit-Position: refs/heads/master@{#76234}
Rather than depending on slow signature checks, receiver type checks are
performed using fast numeric instance type checks.
This CL adds a instance type range for embedders to assign values and
uses these to perform type checks.
Bug: v8:11476
Change-Id: Ie8236ae47ca0ba93ae76a7e690b81aa0a2b0f3e2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2883623
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76162}
Rename CopyAndConvertArrayToCppBuffer as
TryCopyAndConvertArrayToCppBuffer and implement type specialization for
int32_t and double in order to speed up V8 bindings with sequences.
This API is used by Blink code, for example see
https://chromium-review.googlesource.com/c/chromium/src/+/3027405.
Bug: v8:11739
Change-Id: I026a7f5e7833fb1afcc2ea9c296b66c7f733cbb1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3036407
Commit-Queue: Paolo Severini <paolosev@microsoft.com>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76016}
... behind the v8_enable_external_code_space build flag.
This is a first CL in a row of CLs that will make CodeDataContainer
the only type of objects that could contain references to Code objects
(besides the Code objects embedded into the generated code).
Eventually these changes will allow us to move Code space out of the V8
heap cage.
This CL adds |code| field to ensure that CodeDataContainer keeps the
respective Code object alive and |code_entry_point| field that contains
cached value of the code().InstructionStart().
Bug: v8:11880
Change-Id: Ie7ce75667d8da306797d203691b429671bc4530d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2964093
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75179}
This change turns the previously used XOR-based type checks for external
pointers into AND-based type checks. With those, the type tag is ORed
into the top bits of an external pointer when it is written, and the
type check performed on every load is done by ANDing the value with the
inverted tag. This will later allow type checking and masking off the GC
marking bits of external pointers in a single operation.
Bug: v8:10391
Change-Id: I89f2b22588b3f7467c79c7916c11f25cd9bcc82d
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2850639
Commit-Queue: Samuel Groß <saelo@google.com>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74464}
