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  1. 11 Jul, 2022 1 commit
    • Samuel Groß's avatar
      [sandbox] Prepare ExternalPointerTable rollout · 8a59678b
      Samuel Groß authored 
      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/+/3736447Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarAndreas Haas <ahaas@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: 's avatarNico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81636}
      8a59678b
  3. 27 Jun, 2022 1 commit
    • Samuel Groß's avatar
      [sandbox] Turn ExternalPointerTag into a template parameter · 8ca93205
      Samuel Groß authored 
      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/+/3720641Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81402}
      8ca93205
  5. 21 Jun, 2022 1 commit
  7. 09 Jun, 2022 1 commit
  9. 03 May, 2022 1 commit
  11. 23 Mar, 2022 1 commit
  13. 22 Feb, 2022 1 commit
  15. 31 Jan, 2022 1 commit
  17. 18 Jan, 2022 1 commit
  19. 15 Dec, 2021 1 commit
    • Samuel Groß's avatar
      V8 Sandbox rebranding · 277fdd1d
      Samuel Groß authored 
      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/+/3322981Reviewed-by: 's avatarHannes Payer <hpayer@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarMichael Achenbach <machenbach@chromium.org>
Reviewed-by: 's avatarToon Verwaest <verwaest@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78384}
      277fdd1d
  21. 15 Nov, 2021 1 commit
  23. 27 Oct, 2021 1 commit
  25. 24 Aug, 2021 1 commit
    • Dan Elphick's avatar
      Reland "[include] Split out v8.h" · ec06bb6c
      Dan Elphick authored 
      This is a reland of d1b27019

Fixes include:
Adding missing file to bazel build
Forward-declaring classing before friend-classing them to fix win/gcc
Add missing v8-isolate.h include for vtune builds

Original change's description:
> [include] Split out v8.h
>
> This moves every single class/function out of include/v8.h into a
> separate header in include/, which v8.h then includes so that
> externally nothing appears to have changed.
>
> Every include of v8.h from inside v8 has been changed to a more
> fine-grained include.
>
> Previously inline functions defined at the bottom of v8.h would call
> private non-inline functions in the V8 class. Since that class is now
> in v8-initialization.h and is rarely included (as that would create
> dependency cycles), this is not possible and so those methods have been
> moved out of the V8 class into the namespace v8::api_internal.
>
> None of the previous files in include/ now #include v8.h, which means
> if embedders were relying on this transitive dependency then it will
> give compile failures.
>
> v8-inspector.h does depend on v8-scripts.h for the time being to ensure
> that Chrome continue to compile but that change will be reverted once
> those transitive #includes in chrome are changed to include it directly.
>
> Full design:
> https://docs.google.com/document/d/1rTD--I8hCAr-Rho1WTumZzFKaDpEp0IJ8ejZtk4nJdA/edit?usp=sharing
>
> Bug: v8:11965
> Change-Id: I53b84b29581632710edc80eb11f819c2097a2877
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3097448
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dan Elphick <delphick@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#76424}

Cq-Include-Trybots: luci.v8.try:v8_linux_vtunejit
Bug: v8:11965
Change-Id: I99f5d3a73bf8fe25b650adfaf9567dc4e44a09e6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3113629Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarCamillo Bruni <cbruni@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Reviewed-by: 's avatarSimon Zünd <szuend@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76460}
      ec06bb6c
  27. 23 Aug, 2021 2 commits
    • Dan Elphick's avatar
      Revert "[include] Split out v8.h" · 44fe02ce
      Dan Elphick authored 
      This reverts commit d1b27019.

Reason for revert: Broke vtune build, tsan build and possibly others

Original change's description:
> [include] Split out v8.h
>
> This moves every single class/function out of include/v8.h into a
> separate header in include/, which v8.h then includes so that
> externally nothing appears to have changed.
>
> Every include of v8.h from inside v8 has been changed to a more
> fine-grained include.
>
> Previously inline functions defined at the bottom of v8.h would call
> private non-inline functions in the V8 class. Since that class is now
> in v8-initialization.h and is rarely included (as that would create
> dependency cycles), this is not possible and so those methods have been
> moved out of the V8 class into the namespace v8::api_internal.
>
> None of the previous files in include/ now #include v8.h, which means
> if embedders were relying on this transitive dependency then it will
> give compile failures.
>
> v8-inspector.h does depend on v8-scripts.h for the time being to ensure
> that Chrome continue to compile but that change will be reverted once
> those transitive #includes in chrome are changed to include it directly.
>
> Full design:
> https://docs.google.com/document/d/1rTD--I8hCAr-Rho1WTumZzFKaDpEp0IJ8ejZtk4nJdA/edit?usp=sharing
>
> Bug: v8:11965
> Change-Id: I53b84b29581632710edc80eb11f819c2097a2877
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3097448
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dan Elphick <delphick@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#76424}

Bug: v8:11965
Change-Id: Id57313ae992e720c8b19abc975cd69729e1344aa
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3113627
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Owners-Override: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76428}
      44fe02ce
    • Dan Elphick's avatar
      [include] Split out v8.h · d1b27019
      Dan Elphick authored 
      This moves every single class/function out of include/v8.h into a
separate header in include/, which v8.h then includes so that
externally nothing appears to have changed.

Every include of v8.h from inside v8 has been changed to a more
fine-grained include.

Previously inline functions defined at the bottom of v8.h would call
private non-inline functions in the V8 class. Since that class is now
in v8-initialization.h and is rarely included (as that would create
dependency cycles), this is not possible and so those methods have been
moved out of the V8 class into the namespace v8::api_internal.

None of the previous files in include/ now #include v8.h, which means
if embedders were relying on this transitive dependency then it will
give compile failures.

v8-inspector.h does depend on v8-scripts.h for the time being to ensure
that Chrome continue to compile but that change will be reverted once
those transitive #includes in chrome are changed to include it directly.

Full design:
https://docs.google.com/document/d/1rTD--I8hCAr-Rho1WTumZzFKaDpEp0IJ8ejZtk4nJdA/edit?usp=sharing

Bug: v8:11965
Change-Id: I53b84b29581632710edc80eb11f819c2097a2877
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3097448Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Reviewed-by: 's avatarCamillo Bruni <cbruni@chromium.org>
Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76424}
      d1b27019