Commit graph

22 commits

Author SHA1 Message Date
Mitch Phillips
8fe5127027 Recoverable GWP-ASan: Don't tell ActivityManager
Currently, debuggerd tells the teacher that an app that received a fatal
signal. On the playground, dobbing on a process that doesn't actually
need to be killed is considered a friendship-ending move.

Because recoverable GWP-ASan is *supposed* to not crash your app,
suppress this behaviour and don't let ActivityManager know about the
crash.

Bug: N/A
Test: Run a use-after-free in an app that's using recoverable GWP-ASan,
through the 'libc.debug.gwp_asan.recoverable.<app_name>=1' and
'libc.debug.gwp_asan.process_sampling.<app_name>=1' sysprops.

Change-Id: I033ea67d577573df10936e37db7302d4f4bc0069
2023-02-07 17:06:32 -08:00
Mitch Phillips
18ce54241c Add recoverable GWP-ASan.
Recoverable GWP-ASan is a mode landed upstream in
https://reviews.llvm.org/D140173. For more information about why/what it
is, see
https://android-review.git.corp.google.com/c/platform/bionic/+/2394588.

This patch makes debuggerd call the required libc callbacks for GWP-ASan
to recover from the memory corruption. It also adds the functionality
that libart/sigchain eventually ends up calling, which dumps a GWP-ASan
report for the first error encountered.

Test: Build the platform, run sanitizer-status in recoverable mode,
asserting that it doesn't crash but we get a debuggerd report.
Bug: 247012630

Change-Id: I27212f7250844c20a8fd1e961417cdb4e5bd3626
2023-02-01 15:25:29 -08:00
Florian Mayer
bd49c387f0 Use scudo_ring_buffer_size from process_info
This is a no-op but will be used in upcoming scudo changes that allow to
change the buffer size at process startup time, and as such we will no
longer be able to call __scudo_get_ring_buffer_size in debuggerd.

Bug: 263287052
Change-Id: I350421d1fcdf22ce3b8b73780b88c1e10fa8a074
2023-01-05 15:14:56 -08:00
Alessandra Loro
7bd6dca855 Resolve ro.debuggable at build time
Test: n/a
Bug: 243645021

Change-Id: I42c4b1e81383d83c73a565c5e74ac22f17389faf
2022-09-01 13:32:36 +00:00
Peter Collingbourne
bb4b49c63c Teach debuggerd to pass the secondary ring buffer to __scudo_get_error_info().
With this change we can report memory errors involving secondary
allocations. Update the existing crasher tests to also test
UAF/overflow/underflow on allocations with sizes sufficient to trigger
the secondary allocator.

Bug: 135772972
Change-Id: Ic8925c1f18621a8f272e26d5630e5d11d6d34d38
2021-02-12 12:30:52 -08:00
Peter Collingbourne
f86225206d Add support for MTE error reports in tombstones.
Teach debuggerd to use the new scudo APIs proposed in
https://reviews.llvm.org/D77283 for extracing MTE error reports from crashed
processes, and include those reports in tombstones if possible.

Bug: 135772972
Change-Id: I082dfd0ac9d781cfed2b8c34cc73562614bb0dbb
2020-04-27 13:15:49 -07:00
Peter Collingbourne
f3d542fe9f Create a debugger_process_info data structure with the process info pointers.
Similar to r.android.com/1247247 I'll be adding more of them for MTE.

Also, change the protocol between the crasher and crash_dump to make
it easier to add new fields and change the referenced data structures
without needing to worry about versioning. The version number for
static executables is now always 1 (where the protocol will never
change), while the version number for dynamic executables is always
4 (where the protocol can change, because the linker and crash_dump
are version locked).

Bug: 135772972
Change-Id: Ib4696d0544d7c87cb429aaaa15f18c3640059e16
2020-03-24 17:23:15 -07:00
Elliott Hughes
530ab81e42 debuggerd: add an opt-out for OEMs that would rather collect core dumps.
On userdebug/eng devices, check a system property to see whether we
should create tombstones or not. OEMs that would rather have core dumps
can set this property and configure /proc/sys/kernel/core_pattern
appropriately.

Bug: https://issuetracker.google.com/149663286
Test: set the property, cause a crash
Change-Id: If894b4582a1820b64bdae819cec593b7710cb6e3
2020-02-25 09:28:24 -08:00
Mitch Phillips
e0b4bb1b2e [GWP-ASan] Add GWP-ASan information to tombstones.
GWP-ASan can provide information about a crash that it caused. Grab the
GWP-ASan regions from the globals shared by the linker for crash-handler
purpopses, pull the information from GWP-ASan, and display it.

This adds two regions:
 1. Causality tracking by GWP-ASan. We now print a cause header about
 the crash, like `Cause: [GWP-ASan]: Use After Free on a 1-byte
 allocation at 0x7365bb3ff8`
 2. Allocation and deallocation stack traces.

Bug: 135634846
Test: atest debuggerd_test

Change-Id: Id28d5400c9a9a053fcde83a4788f971e677d4643
2020-02-18 16:49:50 -08:00
Josh Gao
a48b41bcb8 debuggerd: switch to using platform headers for DEBUGGER_SIGNAL.
Test: treehugger
Change-Id: Ie9736c4a077dba1029d2352bd94d47ce07323aec
2019-12-17 16:36:05 -08:00
Narayan Kamath
a73df601b7 tombstoned: allow intercepts for java traces.
All intercept requests and crash dump requests must now specify a
dump_type, which can be one of kDebuggerdNativeBacktrace,
kDebuggerdTombstone or kDebuggerdJavaBacktrace. Each process can have
only one outstanding intercept registered at a time.

There's only one non-trivial change in this changeset; and that is
to crash_dump. We now pass the type of dump via a command line
argument instead of inferring it from the (resent) signal, this allows
us to connect to tombstoned before we wait for the signal as the
protocol requires.

Test: debuggerd_test

Change-Id: I189b215acfecd08ac52ab29117e3465da00e3a37
2017-05-31 10:35:32 +01:00
Narayan Kamath
2d377cd688 tombstoned: Add a shared library version of libtombstoned_client...
.. for ART and the frameworks to link against. In the new stack dumping
scheme (see related bug), the Java runtime will communicate with
tombstoned in order to obtain a FD to which it can write its traces.

Also move things around to separate headers that are private
implementation details from headers that constitute the public debuggerd
API. There are currently only three such headers :

- tombstoned/tombstoned.h
- debuggerd/client.h
- debuggerd/handler.h

Bug: 32064548
Test: make

Change-Id: If1b8578550e373d84828b180bbe585f1088d1aa3
2017-05-22 16:55:21 +01:00
Narayan Kamath
922f6b22fc tombstoned: Support java trace dumps.
The changes here involve :
- Creating and opening a new socket to receive trace dump requests on. Having
  different sockets allows us to install different sets of access control rules.

- A minor refactor to allow us to share common pieces of implementation
  between the java and native dumping code. This will also allow us to
  add a unit test for all file / directory related logic.

There are two java trace specific additions here :
- We use SO_PEERCRED instead of trusting the PID written to the seocket
  because requests come in from untrusted processes.
- Java trace dumps are not interceptible.

kJavaTraceDumpsEnabled is set to false for now but the value of the flag
will be flipped in a future change.

Bug: 32064548
Test: Manual; Currently working on a unit_test for CrashType.

Change-Id: I1d62cc7a7035fd500c3e2b831704a2934d725e35
2017-05-18 12:01:14 +00:00
Josh Gao
287d50dc59 debuggerd_client: fix infinite timeouts.
Bug: http://b/36897117
Test: debuggerd_test
Test: debuggerd -b `pidof zygote`
Change-Id: I743433bc420b1c433b82ef62795abb6ea9f5d840
2017-04-04 14:08:54 -07:00
Josh Gao
460b336d6a tombstoned: fix a race between intercept and crash_dump.
Previously, there was no way to detect when tombstoned processed an
intercept request packet, making it possible for a intercept request
followed by a crash_dump being processed in the wrong order.

Add a response to intercept registration, to eliminate this race.

Test: debuggerd_test
Change-Id: If38c6d14081ebc86ff1ed0edd7afaeafc40a8381
2017-03-30 16:49:02 -07:00
Josh Gao
e1aa0ca58a debuggerd_handler: implement missing fallback functionality.
Allow the fallback implementation to dump traces and create tombstones
in seccomped processes.

Bug: http://b/35858739
Test: debuggerd -b `pidof media.codec`; killall -ABRT media.codec
Change-Id: I381b283de39a66d8900f1c320d32497d6f2b4ec4
2017-03-09 11:26:05 -08:00
Josh Gao
4decbe0d6c debuggerd_handler: add SIGSYS to the list of handled signals.
Bug: http://b/34586922
Test: kill -SYS $$
Change-Id: I31dadb9c65141d0c5556cc7256439e0a8d1519ab
2017-01-23 16:01:14 -08:00
Josh Gao
575941115e crash_dump: clear the default crash handlers.
crash_dump is a dynamic executable that gets the default crash dumping
handlers set by the linker. Turn them off to prevent crash_dump from
dumping itself.

Bug: http://b/34472671
Test: inserted an abort into crash_dump
Change-Id: Ic9d708805ad47afbb2a9ff37e2ca059f23f421de
2017-01-23 11:34:49 -08:00
Josh Gao
cbe70cb0a8 debuggerd: advance our amazing bet.
Remove debuggerd in favor of a helper process that gets execed by
crashing processes.

Bug: http://b/30705528
Test: debuggerd_test
Change-Id: I9906c69473989cbf7fe5ea6cccf9a9c563d75906
2017-01-17 13:57:57 -08:00
Josh Gao
218f7fb68e debuggerd: report crashes even when out of file descriptors.
Use nasty clone hacks to let us close random file descriptors to be
able to connect to debuggerd when the fd table is full.

Bug: http://b/32013594
Test: crasher exhaustfd-SIGSEGV
Change-Id: I47772e9a5994da4473bd935b105d9c36827c017a
2016-10-07 18:04:05 -07:00
Josh Gao
a04c80255c debuggerd: remove unnecessary arguments.
These were previously required when bionic used tgkill to reraise
signals, but now that we use rt_tgsigqueueinfo to reraise signals, they
are no longer necessary.

Change-Id: I46ba9f14039a727d0a2c4c3a9d93a3532ba8f263
2016-08-12 11:00:18 -07:00
Josh Gao
9c02dc5916 debuggerd: add libdebuggerd_client.
Bug: http://b/24414818
Change-Id: I079c534d2c952b6975bf0428eb86cc7a55525737
2016-06-17 13:11:29 -07:00