This way, the profilers will know they have to reparse maps.
Bug: 163130539
Test: Verified updated unit tests pass.
Change-Id: I88a801ffdda12811eab5e4833dcf472f2d75c09a
This patch adds support for handling return addresses signed with
pointer authentication. It simply strips the authentication code
without verifying its correctness, and thus works with both A and B
keys and through key-change boundaries.
Additons:
* DW_CFA_AARCH64_negate_ra_state: new CFA operation.
* RA_SIGN_STATE: new pseudo register.
* Pass the arch to DwarfCfa so that the new op is only executed
on aarch64.
The stripping uses the xpaclri instruction. This is a hint space
instruction which is compatible with pre Armv8.3-A devices. For cases
where it cannot be used, a mask can be set instead.
Test: libunwindstack_test
Without this patch all UnwindTest.* testcases should fail if
compiled with Pointer Authentication.
The tests should be executed with both -mbranch-protection=pac-ret and
pac-ret+leaf flags so that either some or all functions have pointer
authentication instructions.
Change-Id: Id7c3f1d0e2fc7fccb19bd1430826264405a9df7c
This function is responsible for majority of CPU time in prefetto.
Reduce the number of memory reads (don't read strings byte-by-byte).
Update all calls of ReadString to include the third parameter to have
a max read.
Add an Elf creation benchmark since this function is on the elf
creation path.
Test: libunwindstack_unit_test
Change-Id: Ia36e1f1a5ba76c9e9f13c43fb9e3691dde7897f2
This uses an experimental Linux kernel API for reading the tags across
processes using ptrace.
Bug: 135772972
Test: Unit tests pass.
Change-Id: Ib1a09d9219166011de80cf250b756bb8a4bcdb0a
If the Dex file we're trying to examine is already within the unwinder's
address space, we don't need to load it from disk or copy it across
processes.
This avoids using up virtual address space to map in dex files, and
also should be a bit faster to read since it won't go out to the file.
Patch by Chris Sarbora
Test: Ran new unit tests.
Test: Ran 137-cfi art test.
Change-Id: I949457856f051cca11b9020e9da3a41bbf6e5c8e
GWP-ASan uses frame-pointer based unwinding internally on
allocation/deallocation to collect stack traces that are used when
crashes are reported.
This should be generic, so pull it out into libunwindstack so it can be
used by MTE as well.
Bug: 152412331
Test: atest debuggerd_test
Change-Id: I27b32263aac63446f5fe398af108676b70cd3971
We're now using it in contexts that don't have all of the registers available,
such as GWP-ASan and soon MTE, so it doesn't make sense to have it be a
member function of Regs.
Bug: 135772972
Change-Id: I18b104ea0adb78588d7e475d0624cefc701ba52c
For now this leaves the ability to cross-unwind a mips process, but we
should probably clean that up too. We need to remove the build remnants so
that we can clean up the build system itself (otherwise it sees us talking
about an architecture it doesn't know about, and assumes that something's
wrong).
Test: treehugger
Change-Id: I2862c630cec95dbdd474e34c3568d0e1a6d44b16
Recently, the maps for an elf in memory might show up looking like:
f0000-f1000 0 r-- /system/lib/libc.so
f1000-f2000 0 ---
f2000-f3000 1000 r-x /system/lib/libc.so
f3000-f4000 2000 rw- /system/lib/libc.so
The problem is that there is logic in the code that assumed that the
map before the execute map must be the read-only map. In the case
above, this is not true. Add a new prev_real_map that will point
to the previous map that is not one of these empty maps.
This will fix the backtraces that look like this:
#00 pc 0000000000050d58 /apex/com.android.runtime/lib64/bionic/libc.so!libc.so (offset 0x50000) (syscall+24) (BuildId: 5252408bf30e395d49ee270b54c77ca4)
To get rid of the !libc.so and the offset value, which is not correct.
Added new unit tests to verify this.
Added new offline test which an empty map between read-only and execute
map. Before this change, the backtraces had lines like
libc.so!libc.so (offset XXX) would be present.
Bug: 148075852
Test: Ran unit tests.
Change-Id: Ie04bfc96b8f91ed885cb1e655cf1e346efe48a45
The function StepIfSignalHandler assumed that the rel_pc passed
to it was actually an elf offset. A new version of clang created a libc.so
that has a load bias, so tests unwinding through a signal handler
would fail on arm. On other ABIs, there is unwind information that could
be used instead, so the unwind still worked.
The fix is to subtract the load bias from the rel_pc to get an elf
offset to pass to the Register StepIfSignalHandler functions. Change all
of the Register funtions to make it clear what the first parameter means.
Add a unit test for this new code. Also, add an offline test for
this case.
Bug: 145683525
Test: Ran unit tests using the new clang and the old clang.
Change-Id: I3e249653b79bcad6d3a56411a7911fde4888e9d6
The code was not properly getting the variable addresses and using
the offset and address fields of the .data section.
Fix all of that, and update the tests.
Bug: 145162678
Test: Unit tests pass.
Test: ./art/test/run-test --dex2oat-jobs 4 --host --prebuild --compact-dex-level fast --jit --no-relocate --runtime-option -Xcheck:jni 137-cfi
Test: ./art/test/testrunner/testrunner.py -t 137 --host
Change-Id: Ic61c4487334fd2273cda9c56eb1a3b525a03edb7
No longer require that NO_LIBDEXFILE_SUPPORT be defined or not
defined when including the header files. Move all of the different
behavior to the implementation, and keep all of the classes the
exact same whether dexfiles are supported or not.
Bug: 144470551
Test: Ran libunwindstack unit tests, libbacktrace unit tests, and
Test: debuggerd unit tests.
Test: Ran host art 137-cfi tests.
Change-Id: I4a04cfbc5d4f1bf765ef154881046c85057006c8
A thread's PSTATE can sometimes be critical for understanding a crash,
especially with MTE and other new features that store per-thread state
in PSTATE.
Bug: 135772972
Change-Id: I1bee25bffe7eea395f04b6449dc9227298cf866e
Due to a bug, an elf can have FDEs with a length of zero, while still
having another FDE for the same pc with a non-zero length. The
eh_frame_hdr can sometimes point to the zero length FDE, but it should
have pointed to the non-zero length FDE. In order to fix this, if the
eh_frame_hdr points at the zero length FDE then try and find the real FDE
directly from eh_frame.
The change cleans up and removes unused variables from DwarfEhFrameWithHdr
and changes the objects so that all of the DwarfSection objects and
DwarfEhFrameWithHdr object inherit from the same class.
Add new unit tests to verify this functionality.
Bug: 142483624
Test: Unit tests all pass.
Change-Id: I128a916e3ba378931de7d44ee15e57e24d4073df
The original code assumed that the load bias in the program headers
would be exactly the same as in eh_frame/eh_frame_hdr/debug_frame.
This isn't guaranteed, so add a section bias for use when creating
a DwarfSection. In addtion, make the load bias and section bias
a signed value. There is no reason that this value needs to be positive,
so don't force it to be.
Add a new offline test that has a different load bias in eh_frame than
in the executable load.
Add additional unit tests to verify the load bias values are set properly.
Clean up the tests in ElfInterfaceTest, making all tests names follow the
same convention.
Bug: 141888859
Bug: 142094469
Test: New units and old unit tests pass on host and taimen.
Change-Id: Ib878123ab5545f0f315c749cfe0d27b012d873ee
Avoid accessing nullptr of already deleted entry.
Add new unit tests that pass with the fix and fail without.
Test: fixes unwinding in ART gcstress tests
Test: All unit tests pass.
Change-Id: Ideb00e2adc899904dd6aeb5dad3fb6fad150322d
Add a specific test that __libc_init is the last frame in a stack
when run on device. In addition, it verifies that the return address
register is marked as undefined given the unwind.
Bug: 140008396
Test: New unit test passes on arm/arm64 (taimen device).
Test: New unit test passes on x86 (cuttlefish).
Test: New unit test passes on x86_64 (modified bionic/tests/run-on-host.sh)
Change-Id: Iefc151a7dbf52ab083c2bb78bad3d38b4e9e1254
There are many subclasses of the Memory class and the overwhelming
majority of them don't need to be exposed externally. We move all of
them to internal headers except MemoryOfflineBuffer, which moves to a
separate header. This dramatically reduces the exposed API surface and
makes the code more modular.
Also, remove the Offline code from libbacktrace. It's not used any where.
Test: Unit tests pass, clean tree still builds
Change-Id: I55dacdf080daba0bfe65c1ad53a4b326bb482e83
Modify the unwinder library to indicate that at least one of the stack
frames contains an elf file that is unreadable.
Modify debuggerd to display a note about the unreadable frame and a possible
way to fix it.
Bug: 129769339
Test: New unit tests pass.
Test: Ran an app that crashes and has an unreadable file and verified the
Test: message is displayed. Then setenforce 0 and verify the message is
Test: not displayed.
Change-Id: Ibc4fe1d117e9b5840290454e90914ddc698d3cc2
This refactors the step function slightly to split it up into
distinct pieces since the code needs to handle a signal handler
versus normal step slightly differently.
Add a new error for an invalid elf.
Modify libbacktrace code to handle new error code.
Bug: 130302288
Test: libbacktrace/libunwindstack unit tests.
Change-Id: I3fb9b00c02d2cf2cc5911541bba0346c6f39b8e6
Update the entries only when the list is modified by the runtime.
Check that the list wasn't concurrently modified when being read.
Bug: 124287208
Test: libunwindstack_test
Test: art/test.py -b --host -r -t 137-cfi
Change-Id: I87ba70322053a01b3d5be1fdf6310e1dc21bb084
Update debuggerd to print BuildId information by default.
Bug: 120975492
Test: New unit tests pass.
Test: debuggerd -b <PID> shows build id information.
Test: tombstones include build id information.
Change-Id: I019b031113d0b77385516223c63455b868924440
Changes:
- Change GetSoname to always returns a std::string.
- Added new unit tests for the soname printing.
- Modify the GetElf() function to save the same elf when we see rosegment
linkers that split the read-only and read-write across a map. This
avoids creating multiple elf objects for each map.
- Fixed a few offline unwind tests.
Bug: 29218999
Test: Unit tests pass.
Change-Id: Iad7c38b5c2957a8c5fd4ba94ebec335bafcad57d
Currently, moving or copying a Maps object leads to double free of MapInfo.
Even moving a Maps object did not prevent this, as after a move
the object only has to be in an "unspecified but valid state", which can
be the original state for a vector of raw pointers (but not for a vector
of unique_ptrs).
Changing to unique_ptrs is the most failsafe way to make sure we never
accidentally destruct MapInfo.
Test: atest libuwindstack_test
Failed LocalUnwinderTest#unwind_after_dlopen which also fails at master.
Change-Id: Id1c9739b334da5c1ba532fd55366e115940a66d3
The GetBuildID() function returns the raw build id data, so add a function
to get the printable hex version of the data.
Bug: 120606663
Test: New unit tests pass.
Change-Id: Ia5aefc97457efb08bbd30ea96cbb2d47ae59f954
Actually make the destructor virtual so that objects in
UnwinderFromPid get freed.
Also, explicitly make the DexFiles and JitDebug destructors virtual.
Bug: 123099840
Test: Ran UnwindTest.local_from_pid thousands of times.
Change-Id: I8bf11c0eb3587fa82f5f14f4723ea5c91da0fd46
Change the GetBuildID function to return a std::string.
Added benchmark to check how long it takes to get the build id from
a file versus an elf object.
Added a way to get an elf without passing in a valid process_memory and
added tests for this.
Test: New unit tests.
Change-Id: I3029019767e0181c758d611fe635bc1bf72d6e8e
This object is able to be easily used from other code and can be used
to replace the libbacktrace calls in other parts of the platform.
Also, demangle the function names when calling FormatFrame.
Bug: 120606663
Test: Unit tests pass, debuggerd using this code directly passes unit
Test: tests.
Change-Id: Ifd8cf9bdd89174c1736810711d20e9f37f29b1bf
This reverts commit 444e23d2fc.
The rest of the topic doesn't need to be reverted.
Reason for revert: Breaks renderscript on marlin and sailfish.
Test: Manual repro of http://b/121110092#comment1 on reported branch
Test: "atest CtsRenderscriptTestCases" on that branch
Test: mmma system/core/{libunwindstack,libbacktrace}, run host gtests
Test: Make image, flash, and reboot device.
Bug: 121110092, 119632407
Change-Id: If1976b19ce386c95bc5bd4fd6d523745c167de18
The linker was modified so that a shared library has a read-only
map, then a read-execute map to represent the whole shared library.
When backtraces are created, then the offsets are set incorrectly
for backtraces. For example, all backtraces wind up with an offset now,
and a shared library loaded out of an apk shows the wrong offset.
Changes:
- Fix the FormatFrame function which was putting the offset before the
map name.
- Refactor the Maps and MapInfo classes to keep track of the previous map
instead of all maps. This was the only map that was ever needed.
- Modify the unwind_for_offline tool to capture both the read-only and
read-execute map when using the read-only segment option.
Bug: 120981155
Test: Updated unit tests pass.
Test: Unwinds on device don't show the offsets everywhere any more.
Change-Id: I75b3727221be9c20316dfdcd7a1c6d242d7ce948
When a shared library is loaded directly from an apk, the new way the
linker splits a shared library into a read-only and execute segment
broke unwinding. Modify the code to handle this case.
Other changes:
- Modify the algorithm for finding read-only map entries. Before, the code
would search the entire map for the closest offset. Now it simply looks
at the previous map. I did this because the old code was too lenient and
might still work even if the linker changes. I want this to break if the
linker behavior changes so that I can analyze the change.
- Update the tools to use PTRACE_SEIZE instead of PTRACE_ATTACH since
PTRACE_ATTACH doesn't work in all cases.
- Small refactor of the GetFileMemory function.
- Add new unit test cases and new offline unwind test cases.
Bug: 120618231
Test: Ran new unit tests, ran original failing test.
Change-Id: I4bade55cf33220d52f1d5e9b0cbbbcc8419669d4
This will be used by heapprofd to allow us to correlate build ids with
memory leaks in libraries and binaries.
Test: m
Test: host libunwindstack_test
Test: run unwind_info against my phone's libc.so (32/64) and compare
to readelf Build ID output.
Bug: 120186412
Change-Id: I3cefd6cce9a8733509bf35b7175eb0f967783477
To avoid a case where a malicious app might try and trick the system to
create an elf and register object that mismatches, always verify that they
are the same arch.
Test: Ran unit tests.
Change-Id: I66978e9e02f8e4f396856912e7019528ead4838e
Every real call always sets the value to true to init the gnu_debugdata
interface, so remove this parameter.
Test: Builds, unit tests pass.
Change-Id: I07fb3adbbd5b65b51c0dc7608561e820a5095051
If multiple threads are unwinding at the same time, new maps that contain
the global variables for dex files and jit information are created. This
leads to threads creating more new maps that then get searched, then
more maps, then more searching until virtual address space exhaustion.
Fix this so that we only search maps that have a corresponding rw map that
could contain the global memory.
Small refactor to combine the code to search for global variables into
one class that both classes inherit from.
Modify unit tests for the new pattern checking.
Bug: 117761427
Test: Ran unit tests for libunwindstack/libbacktrace/simpleperf.
Test: Ran art 004-ThreadStress that used to fail.
Change-Id: I837ca6b9d0383100079de090bc7d019598e0cdfe
The function should have returned a bool, so now it does.
Also use a different lighter weight function for validating the elf
in one place that didn't need to keep the max size value.
Test: Unit tests pass.
Change-Id: Ibde674e608091ba04abf22fad2fdc4dbdb2c6e73
Josh Gao