glibc marks various allocation functions as `throw()`. This addition
hasn't been a problem until we tried to enable C++17, where clang
started complaining that we were redeclaring functions with mismatched
exception specifications. Peculiarly, glibc declares virtually
everything we redeclare as `throw()`, but clang only complains about the
mismatches for a particular subset of functions.
The approach taken in this patch is to add another potentially defined
macro to malloc_decls.h, `NOTHROW_MALLOC_DECL`. This macro works
exactly like `MALLOC_DECL`, except that clients can define
`NOTHROW_MALLOC_DECL` to add appropriate `throw()` specifiers when
declaring functions at global scope, and thereby avoid mismatched
exception specifications.
Differential Revision: https://phabricator.services.mozilla.com/D44045
--HG--
extra : moz-landing-system : lando
In the MinGW build, calls to malloc inside mozglue were not being
redirected as defined in the .def file. We create aliases for the
redirected functions to correctly redirect them inside mozglue.
An alternate solution for this exists. Rather than creating the
importlib during the linking step for mozglue, we could have used
dlltool to create it, and then provided it during linking. This
would allow mozglue to know that it should redirect calls to malloc
to je_malloc as specified in the .def file.
Differential Revision: https://phabricator.services.mozilla.com/D38407
--HG--
extra : moz-landing-system : lando
While here, properly export StackWalk.h when building with
--enable-project=memory.
Differential Revision: https://phabricator.services.mozilla.com/D40731
--HG--
extra : moz-landing-system : lando
None of the StringTable implementations were freeing their strdup'd
strings, either.
Differential Revision: https://phabricator.services.mozilla.com/D40757
--HG--
extra : moz-landing-system : lando
The most important part is the `GetPHCAddrInfo()` function in
`exception_handler.cc`, which extracts a crash address from an
`EXCEPTION_POINTERS` object.
The commit also changes the code so that it works if MozStackWalk() returns an
empty stack trace. This happens in practice on Windows on automation sometimes,
I'm not sure why.
The rest of the commit is just plumbing and the smoothing over of minor
platform differences.
Differential Revision: https://phabricator.services.mozilla.com/D39841
--HG--
extra : moz-landing-system : lando
- On Android, we were already doing it, but using fallible allocations.
- On *nix, it probably doesn't make a difference, but can't hurt. For
most things in Gecko, operator new/delete are inlined and thus
replaced by direct calls to the underlying allocator functions
(moz_xmalloc, malloc, etc.). This may have a benefit for some third
party libraries that would otherwise go through libstdc++'s to
eventually end up back into our allocator via the zone allocator
on macOS and via the exported symbols on others.
- On Windows, because of how some CRT static libraries are, a non-inlined
operator new (thanks to some disabled STL wrapping) would end up linked
against the system malloc, causing problems.
Overall, this can only be better. This also reduces the number of places
where we define those functions.
And on Android, this means operator new within mozglue becomes infallible,
which is more consistent with everything else.
Differential Revision: https://phabricator.services.mozilla.com/D36166
--HG--
extra : moz-landing-system : lando
Bug 1147248 added the workaround for GCC 4.9, but from an attempt with
GCC 6, it seems unnecessary anymore.
Differential Revision: https://phabricator.services.mozilla.com/D36165
--HG--
extra : moz-landing-system : lando
- On Android, we were already doing it, but using fallible allocations.
- On *nix, it probably doesn't make a difference, but can't hurt. For
most things in Gecko, operator new/delete are inlined and thus
replaced by direct calls to the underlying allocator functions
(moz_xmalloc, malloc, etc.). This may have a benefit for some third
party libraries that would otherwise go through libstdc++'s to
eventually end up back into our allocator via the zone allocator
on macOS and via the exported symbols on others.
- On Windows, because of how some CRT static libraries are, a non-inlined
operator new (thanks to some disabled STL wrapping) would end up linked
against the system malloc, causing problems.
Overall, this can only be better. This also reduces the number of places
where we define those functions.
And on Android, this means operator new within mozglue becomes infallible,
which is more consistent with everything else.
Differential Revision: https://phabricator.services.mozilla.com/D36166
--HG--
extra : moz-landing-system : lando
Bug 1147248 added the workaround for GCC 4.9, but from an attempt with
GCC 6, it seems unnecessary anymore.
Differential Revision: https://phabricator.services.mozilla.com/D36165
--HG--
extra : moz-landing-system : lando
This allows freelist randomization on a per-arena basis, by supplying parameters to
arena creation.
It uses an xorshift PRNG with a 128-bit state. It is not cryptographically secure. An
attacker who can observe outputs of the RNG, or read its state, is already in a position
to bypass the randomization applied. At the same time we make its state 128 bit to prevent
a trivial bypass if one or two outputs are observed.
The way a run selects masks to check has not been modified, so the randomization is limited
to at most 32 bits in the current mask being tested. It should be noted that while allocations
from the same run may now be non deterministic (up to the maximum entropy as previously
stated), an attacker who can perform multiple allocations will still be able to allocate
a targeted free region (for example while exploiting a use after free vulnerability in the
DOM). Non deterministic allocations will only impede an attacker who has less control over
how they allocate a targeted free region, and may provide some benefit during exploitation
of a heap based buffer overflow vulnerability where the attacker wishes to construct a
precise layout of regions pre overflow.
Differential Revision: https://phabricator.services.mozilla.com/D32219
--HG--
extra : moz-landing-system : lando
`jemalloc_replace_dynamic()` is badly broken. If you install a malloc table
other than the default at startup (e.g. DMD's or PHC's), when you call
`jemalloc_replace_dynamic()` it installs a new allocator that wraps the
*default* allocator, and then when you call `jemalloc_replace_dynamic(nullptr)`
it switches back to the *default* allocator.
This commits makes numerous improvements.
- It removes the "flip-flopping" between malloc tables, which didn't really
work and isn't necessary.
- `jemalloc_replace_dynamic()` now switches between the *original* malloc table
and the new one, rather than the *default* malloc table and the new one.
- It renames various things, to make the names shorter and clearer.
- It clearly documents the dangers and limitations of
`jemalloc_replace_dynamic()`.
- It removes and inlines `profiler::Init()`, because there was only one call
site.
- It rearranges `install_memory_counter()` so the control flow is simpler.
Differential Revision: https://phabricator.services.mozilla.com/D34266
--HG--
extra : moz-landing-system : lando
This makes it less mozjemalloc-specific, which is helpful for PHC. No non-test
code uses the extra detail anyway.
Differential Revision: https://phabricator.services.mozilla.com/D34441
--HG--
extra : moz-landing-system : lando
The current situation is suboptimal, where we have the same goop
repeated in multiple files, and where things kinda sorta work out fine
thanks to the linker for files that would have been forbidden, except
when the linker doesn't do its job, which apparently happen on
mingwclang builds.
This change only really covers C++ code using operator new/delete, and
not things that would be using malloc/free, because it's easier.
malloc/free is left for a followup.
Differential Revision: https://phabricator.services.mozilla.com/D32119
--HG--
extra : moz-landing-system : lando
MALLOC_STATIC_PAGESIZE is only set on some platforms. Specifically, it's
not set on ia64 and sparc. Which means the case MALLOC_STATIC_PAGESIZE
&& (sparc || ia64) never happens, and gPageSize is never 8 KiB.
Differential Revision: https://phabricator.services.mozilla.com/D31965
--HG--
extra : moz-landing-system : lando
In D25711, I added an arenaId member to `jemalloc_ptr_info_t` when `MOZ_DEBUG`
is defined. This modifies the GTest for `jemalloc_ptr_info()` to ensure that
the new member returns the correct value.
Differential Revision: https://phabricator.services.mozilla.com/D30087
--HG--
extra : moz-landing-system : lando
To ensure that any new JSString has its char buffer allocated in the new arena,
it is useful to be able to query a pointer and assert that it is in the
correct arena (at-least in Debug Build).
This adds the required functionality to mozjemalloc, and JSString can use it
for its new assertion in a later change.
Differential Revision: https://phabricator.services.mozilla.com/D25711
--HG--
extra : moz-landing-system : lando
Changes:
- added comments for tests being disabled
- disabled two additional tests in order to green the run
Differential Revision: https://phabricator.services.mozilla.com/D28085
--HG--
extra : moz-landing-system : lando
To ensure that any new JSString has its char buffer allocated in the new arena,
it is useful to be able to query a pointer and assert that it is in the
correct arena (at-least in Debug Build).
This adds the required functionality to mozjemalloc, and JSString can use it
for its new assertion in a later change.
Differential Revision: https://phabricator.services.mozilla.com/D25711
Changes:
- most tests are skipped using `moz.build` configuration file.
- `MultiWriterQueue` had to be skipped with `define` clauses in the test file due to build bustages when its `moz.build` file was used.
Differential Revision: https://phabricator.services.mozilla.com/D27944
--HG--
extra : moz-landing-system : lando
The jemalloc tests leave behind minidumps. Disable for now, for a green run.
Differential Revision: https://phabricator.services.mozilla.com/D27014
--HG--
extra : moz-landing-system : lando
Christian Holler
Sylvestre Ledru
Nathan Froyd
Tom Ritter
Nicholas Nethercote
Mike Hommey
Cameron McCormack
Mihai Alexandru Michis
Gian-Carlo Pascutto
Jed Davis
Csoregi Natalia
Victor Porof
Nick Thomas
Andreea Pavel
Mike Hommey
Chris Martin
Edwin Gao
Narcis Beleuzu
Geoff Brown
Petr Sumbera
Gurzau Raul