Whereas previously MozDescribeCodeAddress would have handled demangling,
we need to explicitly do that from our new GetFunction method. The string we
generate is now more useful for the profiler to merge -- having dropped the
address in the previous patch, and the file & line number and library in this
patch.
While we're at it, try to demangle Rust symbols too.
Ideally we'd add Rust symbol handling to DemangleSymbol in
StackWalk.cpp, but that lives in mozglue, which currently cannot have
any Rust crate dependencies.
Differential Revision: https://phabricator.services.mozilla.com/D43142
--HG--
extra : moz-landing-system : lando
While mozglue continues to be the correct location for calling the affected
code in this patch, the calls requiring profiler labels will soon be
originating from firefox.exe via the launcher process.
mozglue will be supplying the launcher process with an interface that consists
of what are effectively "OnBeginDllLoad" and "OnEndDllLoad" callback
notifications; obviously an RAII class is not going to be useful for that case.
We still want to keep the RAII stuff around, however, since we still need it
for cases where we need to fall back to using the legacy DLL blocklist.
Differential Revision: https://phabricator.services.mozilla.com/D41807
--HG--
extra : moz-landing-system : lando
While mozglue continues to be the correct location for calling the affected
code in this patch, the calls requiring stackwalk suppression will soon be
originating from firefox.exe via the launcher process.
mozglue will be supplying the launcher process with an interface that consists
of what are effectively "OnBeginDllLoad" and "OnEndDllLoad" callback
notifications; obviously an RAII class is not going to be useful for that case.
We still want to keep the RAII stuff around, however, since we still need it
for cases where we need to fall back to using the legacy DLL blocklist.
Differential Revision: https://phabricator.services.mozilla.com/D41808
--HG--
extra : moz-landing-system : lando
This patch does two things:
1. We refactor the resolution of function pointer and return type so that we
may support additional calling conventions besides just __stdcall;
2. We refactor DynamicallyLinkedFunctionPtr into a base class, and create
StaticDynamicallyLinkedFunctionPtr to specifically handle the static local
use case.
Differential Revision: https://phabricator.services.mozilla.com/D40885
--HG--
extra : moz-landing-system : lando
Profilers will soon be able to set/reset entry&exit functions at different
times, but simultaneously other code may want to use AutoProfilerLabel, so we
need to make this all thread-safe.
All shared static information is now encapsulated in an RAII class that enforces
proper locking before giving access to this information.
Also added a "generation" count, so that if an AutoProfilerLabel is in-flight
when entry&exit functions are changed, the context given by the old entry
function will not be passed to a mismatched new exit function.
Differential Revision: https://phabricator.services.mozilla.com/D34807
--HG--
extra : moz-landing-system : lando
`ProfilingStack*` happens to be the information that the current Gecko Profiler
entry function wants to forward to the exit function, but AutoProfilerLabel does
not really need to know about that.
Changing it to `void*`, so that we can later use different entry/exit functions
that use different context types.
Differential Revision: https://phabricator.services.mozilla.com/D34806
--HG--
extra : moz-landing-system : lando
This patch modifies arm64 so that detours are peformed via two passes:
1. The first pass uses a null trampoline to count how many bytes are available
for patching the original function.
2. If we have >= 16 bytes to patch, we reuse existing trampoline space. If we
have less than 16 bytes to patch, we reserve trampoline space within 128MB
of the function, allowing for a 4 byte patch.
3. Then we recurse, this time using a real trampoline.
Note that we still do a single-pass on x86(-64).
Differential Revision: https://phabricator.services.mozilla.com/D32193
--HG--
extra : moz-landing-system : lando
A null trampoline is just a trampoline that is not backed by a VM reservation.
These are used for tracking the number of bytes that are needed to make a patch.
This patch also contains the changes needed to work with TrampolinePool.
Differential Revision: https://phabricator.services.mozilla.com/D32192
--HG--
extra : moz-landing-system : lando
VMSharingPolicyShared needs to become much smarter. This patch modifies that
policy to track different VM reservations and reuse them whenever possible.
We add TrampolinePools to abstract away the differences between VM policies
with respect to the caller who is making the reservation.
Differential Revision: https://phabricator.services.mozilla.com/D32191
--HG--
extra : moz-landing-system : lando
In order to support 4-byte patches on ARM64, we need to be able to reserve
trampoline space within +/- 128 MB of the beginning of a function.
These changes allow us to make such reservations using OS APIs when
available.
Differential Revision: https://phabricator.services.mozilla.com/D32190
--HG--
extra : moz-landing-system : lando
VMSharingPolicyShared needs to become much smarter. This patch modifies that
policy to track different VM reservations and reuse them whenever possible.
We add TrampolinePools to abstract away the differences between VM policies
with respect to the caller who is making the reservation.
Differential Revision: https://phabricator.services.mozilla.com/D32191
--HG--
extra : moz-landing-system : lando
In order to support 4-byte patches on ARM64, we need to be able to reserve
trampoline space within +/- 128 MB of the beginning of a function.
These changes allow us to make such reservations using OS APIs when
available.
Differential Revision: https://phabricator.services.mozilla.com/D32190
--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
* CreateFileW will return INVALID_HANDLE_VALUE (-1) on failure, not NULL (0).
* MapViewOfFile will map the entire section if the size is 0. No explicit size
is required.
* If SEC_IMAGE is specified, the mapped image size may be different from the
file size on the storage.
Differential Revision: https://phabricator.services.mozilla.com/D32563
--HG--
extra : moz-landing-system : lando
This patch fixes a static destructor order dependency between WindowsDllInterceptor and VMSharingPolicyUnique by telling VMSharingPolicyShared not to access the VMSharingPolicyUnique at destruction. This means that the behavior of intercepted functions is no longer restored in the given process at policy shutdown time.
Differential Revision: https://phabricator.services.mozilla.com/D28764
--HG--
extra : moz-landing-system : lando
TrampolineCollection iterates over an array of Trampolines that it has set 'write' permissions for. If this happens in a process whose sandbox forbids dynamic code then these permissions cannot be set. This patch detects that condition and returns an empty TrampolineCollection in that case. We ASSERT if we fail to set permissions for any other reason.
Differential Revision: https://phabricator.services.mozilla.com/D28613
--HG--
extra : moz-landing-system : lando
Bug 1533808 introduced code to intercept DLL methods that the Chromium sandbox had already intercepted. That patch did not store the the pointer to the intercepted function in the trampoline data, as is done when intercepting other methods.
Differential Revision: https://phabricator.services.mozilla.com/D28612
--HG--
extra : moz-landing-system : lando
This patch fixes a static destructor order dependency between WindowsDllInterceptor and VMSharingPolicyUnique by telling VMSharingPolicyShared not to access the VMSharingPolicyUnique at destruction. See the bug for details of the order dependency.
Differential Revision: https://phabricator.services.mozilla.com/D28764
--HG--
extra : moz-landing-system : lando
This way we don't have to go through a bunch of printf nonsense, and we
ought to be able to arrive at optimized routines that take advantage of
constant radices, etc.
Differential Revision: https://phabricator.services.mozilla.com/D25141
--HG--
extra : moz-landing-system : lando
Due to coming changes involving the IOInterposer, the WindowsDllInterceptor may be set up later than the sandbox. The sandbox hooks some of the same functions, so the Interceptor is running into its hooks instead of the original implementations it anticipated. This patch allows it to recognize and efficiently patch those hooks when that happens.
Differential Revision: https://phabricator.services.mozilla.com/D24654
--HG--
extra : moz-landing-system : lando
In the tree we have two copies of printf_stderr() with the comment,
"Ideally this should be shared". This moves the function to a new exported
header which can be the basis for other similar debugging utility functions.
To include it,
#include "mozilla/glue/Debug.h"
A small concern with this is that printf_stderr() is in the global namespace,
and could conflict if it's inadvertently included along with, for example,
nsDebug.h which also defines this function. The warning in the comment at the
top of the file attempts to mitigate this.
Differential Revision: https://phabricator.services.mozilla.com/D13196
--HG--
extra : moz-landing-system : lando
This patch doesn't cover all possible functions for which we currently
instantiate interceptors inside Firefox/Gecko. Rather than asserting, we just
fail in those cases (at least until we have full coverage of existing uses).
This is okay, as for the upcoming milestone 2 of aarch64 builds, we are most
concerned with successfully being able to hook the following functions:
ntdll!LdrLoadDll
ntdll!LdrUnloadDll
ntdll!LdrResolveDelayLoadedAPI
user32!GetWindowInfo
So, within that context, the aarch64 implementation is fairly simple:
Each instruction is 4-bytes wide. We iterate down each instruction, and if the
current instruction is *not* PC-relative, we just copy it verbatim. If we
encounter an instruction that *is* PC-relative, we either decode it and
rewrite it inside the trampoline, or we fail. For the purposes of milestone 2,
the only instruction that is essential to decode is ADRP.
In bug 1526016 I modify TestDllInterceptor to exclude functions that are not
yet supported by this patch.
Differential Revision: https://phabricator.services.mozilla.com/D19446
--HG--
extra : moz-landing-system : lando
FramePointerStackWalk can trip ASAN when walking the stack and reading outside
of ASAN-protected objects.
Differential Revision: https://phabricator.services.mozilla.com/D20208
--HG--
extra : moz-landing-system : lando
The actual subcategories will be added in later patches, so that there are no
unused categories.
Differential Revision: https://phabricator.services.mozilla.com/D11334
--HG--
extra : moz-landing-system : lando