Commit graph

195 commits

Author SHA1 Message Date
Treehugger Robot
c3d30bfdff Merge "Fix GetGlobalVariableOffset with tagged pointer in aarch64" 2020-05-06 05:53:45 +00:00
Sim Sun
a7a194beb4 Fix dangling pointer issue in LocalUpdatbleMaps
Libunwindstack would remove duplicated items and update the `prev_map`
during reparsing `/proc/self/maps`. But we leave `prev_real_map`
pointing toward a MapInfo that will be deleted soon. It will cause a
dangling pointer issue.

Add new tests to cover this dangling pointer issue.

Bug: 155511785

Test: libunwindstack_test
Change-Id: I62e1b97bcb73f07e9349671f0b758f5ec9de16c0
2020-05-01 22:20:01 +00:00
Martin Stjernholm
4a27a81e4e Reland "bionic_libc_platform_headers is only available when building with Bionic".
Relanding unchanged - the build problem was due to a split topic.

Test: m checkbuild
Test: atest libunwindstack_unit_test
Test: lunch fvp-userdebug && mmm system/core/libunwindstack
Bug: 152255951
Change-Id: Ifd1ced65b840ef216630906eec1ec31233e0c5f1
2020-04-29 18:16:46 +01:00
Martin Stjernholm
87bac1a411 Revert "bionic_libc_platform_headers is only available when buil..."
Reason for revert: Breaks rvc-d1-dev-plus-aosp: http://ab/6443190
Reverted Changes:
Ide447b89a:bionic_libc_platform_headers is only available whe...
Ia93cd3ec8:bionic_libc_platform_headers is only available whe...
Icdc495588:Make bionic_platform_headers available only for Bi...
Idfd7c87dc:bionic_libc_platform_headers is only available whe...

Bug: 152255951
Bug: 155269399
Change-Id: I4e6beba5565e604fde3a51cdce5cc4041caffa4e
2020-04-29 12:18:54 +00:00
Yong Li
fbca300097 Fix GetGlobalVariableOffset with tagged pointer in aarch64
Tagged pointer for aarch64 since Android R would lead top byte to have
random values. For example of a symbol from libart.so in a hwasan
enabled device in Android R:

1490: 8800000000b094a0   144 OBJECT  GLOBAL 24 __dex_debug_descriptor

We need to mask off the top byte so that the address range comparison
would work as intended.

Test: Ran new unit test

Signed-off-by: Yong Li <yongl0722@gmail.com>
Change-Id: Ia8c638e16baff57740c569e9eaf9cfd1f5bd3fad
2020-04-27 21:07:50 +00:00
Martin Stjernholm
03082e6952 bionic_libc_platform_headers is only available when building with Bionic.
Test: m checkbuild
Test: atest libunwindstack_unit_test
Test: lunch fvp-userdebug && mmm system/core/libunwindstack
Bug: 152255951
Change-Id: Idfd7c87dc65db350730fec3ceef8c6bc64acf60b
2020-04-27 19:53:49 +01:00
Christopher Ferris
126b010f15 Merge "Create minimal remap table for symbol binary search." 2020-04-20 23:42:22 +00:00
Christopher Ferris
cec90ea2da Merge "Optimize Memory::ReadString" 2020-04-20 23:35:42 +00:00
David Srbecky
a17c2b694c Optimize Memory::ReadString
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
2020-04-16 15:03:19 -07:00
David Srbecky
af41960acb Create minimal remap table for symbol binary search.
ELF symbols are not sorted by address. Create remap table
which reshuffles the indices into sorted-by-address order.

This saves over 6x of memory (the remap table needs just
uint32_t per entry, as opposed the FuncInfo cache entry).

ART symbols are sorted.  Make use of that fact.

Bug: 110133331
Test: libunwindstack_test
Test: art/test.py -b --host -r -t 137-cfi
Change-Id: I1812d2dd3ad6a69ae93ed50ca387749c649289b9
2020-04-16 18:17:45 +01:00
Peter Collingbourne
c71e0a652c libunwindstack: Add Memory::ReadTag() function for reading memory tags.
This uses an experimental Linux kernel API for reading the tags across
processes using ptrace.

Bug: 135772972

Test: Unit tests pass.
Change-Id: Ib1a09d9219166011de80cf250b756bb8a4bcdb0a
2020-04-16 00:23:45 -07:00
Sim Sun
273d3f08aa Avoid re-mapping dex file that's in local memory.
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
2020-04-07 18:07:38 -07:00
Peter Collingbourne
a7b4c5d25a Fix off-by-one in ReadBuildIDFromMemory.
This was sometimes causing build ids to be truncated, probably because
of memory corruption in std::string. A similar off-by-one was fixed in
ReadBuildID in aosp/939619.

Bug: 129873279
Change-Id: I401fe7f991dbd135f5b4836381b48ea3c6a2243f
2020-03-31 10:29:38 -07:00
Christopher Ferris
a010ddbb88 Merge "Fix memory leak of DexFile handle after release" 2020-03-23 18:20:00 +00:00
Yong Li
489c3a8b35 Fix memory leak of DexFile handle after release
The DexFile handle is allocated from heap in OpenFromFd/OpenFromMemory.
After releasing the unique_ptr, the DexFile handle itself is no longer
managed by the smart pointer. However, the DexFile handle is not freed
in the constructor of DexFileFromFile/DexFileFromMemory.

This change uses get() method to get the DexFile pointer while allowing
it to be managed by smart pointer so that it can be freed after method
end.

Added new unit tests to detect leaks.

Bug: 151966190

Test: Unwinding can still retrieve dex frame information during crash.
Test: Ran new unit tests before change and verified they fail, ran them
Test: after the change and verified they don't fail.

Signed-off-by: Yong Li <yongl0722@gmail.com>
Change-Id: I0627e1e255eb6644aba51e940c1a79ff78d568d7
2020-03-20 16:46:11 -07:00
Peter Collingbourne
5ac3927878 Make GetPcAdjustment a free function.
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
2020-03-19 17:51:20 -07:00
David Srbecky
a6617cb179 Rewrite DwarfSectionImpl::InsertFde
Simplify and fix the algorithm.

For consecutive functions (eg [10,20] [20,30]) without
padding in between, the old algorithm would drop FDEs.

Test: libunwindstack_test
Change-Id: Ie886922bec262fb64d4b2ecf01c2961d0652dcdb
2020-02-22 11:45:42 -08:00
Ryan Savitski
92237bad6a unwindstack: RegsArm64: fix harmless off by 1 + iterate GPRs contiguously
The memcpy should be for 31 GPRs, [x0, x30]. Currently it (accidentally)
also copies over the SP register (which ends up being harmless, as the
layouts match, and the value is reassigned again anyway).

Separately, I'm including an optional change for the iteration order,
since LR is the x30 GPR, it makes slightly more sense to print it
immediately after x29. However, this is a change in behaviour, so I can
undo the change if you think it's not worth it.

Tested: atest libunwindstack_unit_test
Change-Id: Ib6b81f8ee3a9a526bfabe4b09b327f083c855fb8
2020-01-24 19:50:45 +00:00
Christopher Ferris
0f40a05309 Properly handle empty map after read-only map.
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
2020-01-22 18:30:12 -08:00
Christopher Ferris
de5cd8ccd4 Fix global finding logic.
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

That empty map was confusing the logic when looking for a global
variable. Now this case is handled properly.

New unit test added for this case.

Bug: 147910661

Test: Ran unit tests.
Test: Ran original failing test 137-cfi.
Change-Id: Ida2e96d1da5e1bf61f41646949fe5a2d405c0d61
2020-01-21 18:00:57 -08:00
Christopher Ferris
8726d3a448 Fix handling of possible bad gnu_debugdata_size.
Rather than use a std::vector for backing memory, allocate the memory
using a new with nothrow, and in MemoryBuffer use realloc. Since
the size field is coming from the elf, it could be corrupted or
intentionally crafted to cause problems.

In addition, add some other protections to make sure that overflows
don't occur.

Bug: 146215949

Test: Ran unit tests with jemalloc and scudo to verify that they
Test: both behave the same way.
Change-Id: If14243ce382ba5403a6bacd0ec673452c6b7c3be
2019-12-19 16:48:15 -08:00
Treehugger Robot
b773897b01 Merge "Add a name for all test suites" 2019-12-12 02:44:26 +00:00
Haibo Huang
0c01bb6edf Add a name for all test suites
(for the new googletest

Test: run tests
Change-Id: I3856a4a8f3ed23bcfcc59bec7624595e91740be0
2019-12-11 12:46:20 -08:00
Christopher Ferris
f0c82e7bad Use elf offset in signal step check.
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
2019-12-04 22:29:59 +00:00
Christopher Ferris
df683b7439 Fix support finding global variables.
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
2019-12-03 17:35:00 -08:00
Treehugger Robot
ba5351692e Merge "Include PSTATE in tombstones on arm64." 2019-11-19 14:07:37 +00:00
Peter Collingbourne
bb2f941f57 Include PSTATE in tombstones on arm64.
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
2019-11-18 17:57:37 -08:00
Haibo Huang
cf8a5b0e0e Fix build with new googletest
The new googletest requires prefix to be non-empty.

Exempt-From-Owner-Approval: fix test
Change-Id: Ic039cb657b455919e429a3ec2107893b1734e8a1
2019-11-10 04:08:25 +00:00
Christopher Ferris
4ca98e18a4 Fix potential bad info in eh_frame_hdr.
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
2019-10-29 18:39:30 -07:00
Christopher Ferris
5838e53b97 Fix handling of PT_GNU_EH_FRAME.
The bias for the PT_GNU_EH_FRAME was using the paddr instead of vaddr.
This doesn't match the way the load bias is calculated, which always
use vaddr - offset, so change to use vaddr.

Found on an old x86 device that has a vdso that sets vaddr differently
from paddr.

Add a new offline test to catch this case and update the elf interface
unit tests.

Also, fix a small bug in the unwind_for_offline tool.

Bug: 142365899

Test: Unit tests pass.
Change-Id: I5f0bf062dd8ee45aa8553189ba493ec962e0b059
2019-10-21 19:11:22 -07:00
Christopher Ferris
baf058bbf7 Replace MOCK_METHODN with MOCK_METHOD macro.
Test: Builds and unit tests pass.
Change-Id: I64e0034359c213f37c098d1c97be260bd955ca0f
2019-10-11 14:30:18 -07:00
Christopher Ferris
819f13116e Handle when bias is different in elf headers.
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
2019-10-08 17:36:06 +00:00
Christopher Ferris
6c8ac56296 Fix static GetLoadBias function.
The load bias value set in ReadProgramHeaders is out of sync with the
algorithm used in the static GetLoadBias function.

Sync the two and add tests to verify that they stay in sync.

Test: Unit tests pass.
Change-Id: I20ac0104970a22a92a5314a41dcadad0c9c22e64
2019-10-02 17:53:46 -07:00
David Srbecky
f1932fd107 Fix LocalUpdatableMaps
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
2019-09-16 18:28:38 -07:00
Christopher Ferris
7aba5142e9 Add test mapping to run the libunwind tests.
Created a special target, libunwindstack_unit_test, that doesn't
include the test that dlopen's a shared library. It appears atest
doesn't understand how to handle the require keyword.

Also, move the shared library into the libunwindstack_test directory
itself.

Test: Ran atest libunwindstack_unit_test.
Change-Id: I967919b1d74a08669b61d0363d80861685725609
2019-09-03 13:32:51 -07:00
Christopher Ferris
7138232f57 Add test of undefined return address.
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
2019-08-30 23:29:34 -07:00
Christopher Ferris
604ccb147c Merge "Move to isolated testing." 2019-07-18 19:00:46 +00:00
Christopher Ferris
ea8e7d10d7 Move to isolated testing.
Modify the MapInfoCreateMemoryTest to work in the isolated mode.

Test: Ran unit tests on host/target.
Change-Id: I84e01d96e852acd813e0f203b4a207cfaf8ca556
2019-07-17 18:08:32 -07:00
Christopher Ferris
a74aae8033 Move to the libc++ demangler.
The previous versions of the libc++ demangler crashed on bad input.
However, the new version passes a fuzzer and has a lot of tests. Since
it's more complete than the local demangler, use it instead.

Modified the expected output of an offline test since the new demangler
handles a case that didn't work before.

Verified that the time it takes for the check_for_leak tests did not
change after this.

Bug: 136138882

Test: Ran the unit tests.
Test: Verified the __cxa_demangle function passes the fuzzer when run for
Test: hours. Both the 32 bit and 64 bit version of __cxa_demangle were
Test: fuzzed using external/libcxxabi/fuzz.
Change-Id: I10c06b589d57c36d89dbecba020b1ef2da69634a
2019-07-17 13:49:37 -07:00
Florian Mayer
249c90ff17 Fix missing load bias.
There are binaries that have non-executable LOAD with p_offset=0.

E.g.,

Program Headers:
  Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
  PHDR           0x000040 0x0000000000400040 0x0000000000400040 0x0002a0 0x0002a0 R   0x8
  INTERP         0x0002e0 0x00000000004002e0 0x00000000004002e0 0x00001c 0x00001c R   0x1
      [Requesting program interpreter: /lib64/ld-linux-x86-64.so.2]
  LOAD           0x000000 0x0000000000400000 0x0000000000400000 0x0059e0 0x0059e0 R   0x1000
  LOAD           0x006000 0x0000000000406000 0x0000000000406000 0x10f2b05 0x10f2b05 R E 0x1000
  LOAD           0x10f9000 0x00000000014f9000 0x00000000014f9000 0x70f634 0x70f634 R   0x1000
  LOAD           0x1808f18 0x0000000001c09f18 0x0000000001c09f18 0x089fc8 0x0a7ab8 RW  0x1000
  DYNAMIC        0x1864ce0 0x0000000001c65ce0 0x0000000001c65ce0 0x000240 0x000240 RW  0x8
  NOTE           0x0002fc 0x00000000004002fc 0x00000000004002fc 0x000020 0x000020 R   0x4
  TLS            0x1808f18 0x0000000001c09f18 0x0000000001c09f18 0x000010 0x000010 R   0x8
  GNU_EH_FRAME   0x11abde8 0x00000000015abde8 0x00000000015abde8 0x14484c 0x14484c R   0x4
  GNU_STACK      0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x000000 RWE 0x10
  GNU_RELRO      0x1808f18 0x0000000001c09f18 0x0000000001c09f18 0x05c0e8 0x05c0e8 R   0x1

Test: host libunwindstack_test passes.
Test: Modified unit tests and new offline test.

Change-Id: I3992f712be238c7d4109556580b5dcc71175fe19
2019-07-09 10:22:36 -07:00
Christopher Ferris
7e21eba5b7 Switch case to suite to follow new gtest naming.
Bug: 135528735

Test: All unit tests pass.
Change-Id: I1f3dc6fe381ec557b6b7bc5cb1c58d210efa63da
2019-06-20 16:18:57 -07:00
Casey Dahlin
6b95a0e999 Internalize subclasses of Memory
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
2019-06-11 12:09:18 -07:00
Christopher Ferris
d49499d5c9 Set elf_start_offset for invalid elf maps.
Add new unit tests to cover this case.

Bug: 133495043

Test: New unit tests pass.
Change-Id: I9ded5732c3c40197ebfddee3dcacc4aa07541ac0
2019-06-10 18:39:38 -07:00
Christopher Ferris
a4bdb984f9 Display offsets for dex frames.
When adding a dex frame, no offset is ever printed even if the dex data
is coming from a non-zero offset map. Fixed so an offset is printed
in this case.

Previous the line looked like this:

  #17 pc 0000000000500d7a  /product/app/GoogleCamera/GoogleCamera.apk (com.google.android.libraries.camera.async.AndroidPriorityThread.run+10)

Now looks like:

  #17 pc 0000000000500d7a  /product/app/GoogleCamera/GoogleCamera.apk (offset 0x11d0000) (com.google.android.libraries.camera.async.AndroidPriorityThread.run+10)

Add new unit test for this case.

Bug: 134420076

Test: Wrote new unit test, and verified a non-zero offset for dex file
Test: data results in a frame with a non-zero offset.
Change-Id: I58c134fda4fad5456ca0f1723192667a1ca5d509
2019-06-04 12:07:05 -07:00
Christopher Ferris
98aaf4cf08 Ignore memory from elf on /memfd:
In ART, some of the maps are /memfd:/jit-cache and it triggers the warning
about unreadable elf files. Do not set the elf from memory not file
flag in this case.

Bug: 131909548

Test: New unit tests pass.
Test: No warnings dumping stacks with this change done.
Change-Id: Ifba5e65da609525ded75430da173c614f6e4801e
2019-05-03 11:13:17 -07:00
Christopher Ferris
4ae266ccbd Add indicator that an elf is memory backed.
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
2019-04-18 15:37:52 -07:00
Christopher Ferris
d11ed86d65 Fix pc/function name for signal handler frame.
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
2019-04-12 17:23:18 -07:00
Treehugger Robot
b626177d63 Merge "Revert "Check for data races when reading JIT/DEX entries."" 2019-04-06 17:09:10 +00:00
David Srbecky
b9cc4fbb26 Revert "Check for data races when reading JIT/DEX entries."
This reverts commit 85b5fecec9.

Reason for revert: Breaks ART tests, reverting to investigate.

Change-Id: I1bb905407e87cbd4f832646651133a9caf6fcfc8
2019-04-05 18:23:32 +00:00
Christopher Ferris
1760b45709 Fix off by one reading build id.
Update unit tests and add new build id displaying in offline unwinds.

Bug: 129873279

Test: All unit tests pass.
Test: Verify that debuggerd displays build id properly.
Change-Id: I97f4a204842447a20c812f535a458155b937d5e1
2019-04-03 14:51:51 -07:00