Commit Graph

542 Commits

Author SHA1 Message Date
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 7d199de8e2 Merge changes I0ff1fc5c,I7a23d3bf
* changes:
  libdebuggerd: print the build fingerprint in fallback.
  libdebuggerd: implement fallback register dumping on arm/aarch64.
2017-05-10 23:24:38 +00:00
Chenjie Luo 68c24eff77 Remove not-used dependency in crash_dump
Test: Build crash_dump.
Change-Id: I053cf53196b3e438545138ca8401a0ad01006a8c
2017-05-08 15:18:40 -07:00
Josh Gao 2bc6196faa Merge "debuggerd_handler: use syscall(__NR_get[pt]id) instead of get[pt]id." 2017-05-08 20:18:34 +00:00
Josh Gao 62f5977d4a libdebuggerd: print the build fingerprint in fallback.
Bug: http://b/37798209
Test: killall -ABRT media.codec on internal
Change-Id: I0ff1fc5ca1e0bcec2c1b2553d6af7099deebfeda
2017-05-08 13:15:19 -07:00
Josh Gao 77b00ed429 libdebuggerd: implement fallback register dumping on arm/aarch64.
Bug: http://b/35439781
Test: killall -ABRT media.codec on internal
Change-Id: I7a23d3bfcf07ad584e677b2ef5fff28436ef0972
2017-05-08 13:15:19 -07:00
Dan Willemsen a4103a85b6 Turn off debuggerd for host bionic
Bug: 31559095
Test: Attempt to build host bionic
Change-Id: Ie0b30417bdc2c59fd4793a79fd23dc9ccd398937
2017-05-07 13:22:01 -07:00
Josh Gao 2e7b8e2d1a debuggerd_handler: use syscall(__NR_get[pt]id) instead of get[pt]id.
bionic's cached values for getpid/gettid can be invalid if the crashing
process manually invoked clone to create a thread or process, which
will lead the crash_dump refusing to do anything, because it sees the
actual values.

Use the getpid/gettid syscalls directly to ensure correct values on
this end.

Bug: http://b/37769298
Test: debuggerd_test
Change-Id: I0b1e652beb1a66e564a48b88ed7fa971d61c6ff9
2017-05-05 14:58:12 -07:00
Christopher Ferris ac225780dd Move libc_logging to libasync_safe.
Move the name of the "private/libc_logging.h" header to <async_safe/log.h>.

For use of libc_malloc_debug_backtrace, remove the libc_logging library.
The library now includes the async safe log functions.

Remove the references to libc_logging.cpp in liblog, it isn't needed because
the code is already protected by a check of the __ANDROID__ define.

Test: Compiled and boot bullhead device.
Test: Run debuggerd unit tests.
Test: Run liblog unit tests on target and host.
Test: Run libmemunreachable unit tests (these tests are flaky though).
Change-Id: Ie79d7274febc31f210b610a2c4da958b5304e402
2017-05-02 18:38:46 -07:00
Josh Gao e06f2a4886 debuggerd_handler: don't assume that abort message implies fatal.
Applications can set abort messages via android_set_abort_message
without actually aborting. This leads to following non-fatal dumps
printing their output to logcat in the same format as a regular crash.

Bug: http://b/37754992
Test: debuggerd_test
Change-Id: I9c5e942984dfda36448860202b0ff1c2950bdd07
2017-04-27 17:28:05 -07:00
Josh Gao 72ca48e5cb Merge "crash_dump: during early boot, output to kmsg on userdebug." 2017-04-10 20:51:59 +00:00
Josh Gao bf2dd48241 crash_dump: during early boot, output to kmsg on userdebug.
Crashes that happen before tombstoned is running are extremely hard to
diagnose, because tombstones aren't written to disk, and the window of
opportunity to get logs via `adb logcat` is small (potentially
nonexistent).

Solve this by adding a world-writable /dev/kmsg_debug on userdebug
builds, and writing to it in addition to logcat when tombstoned hasn't
started yet.

Bug: http://b/36574794
Test: stop tombstoned; crasher; dmesg
Change-Id: Ib22c02a002afb602933155fb2c9b7a8abbe9ed38
2017-04-06 15:00:52 -07:00
Liu Changcheng 3492221fcf check send_signal result before further dealing
If send_signal failed, debuggerd_trigger_dump should return
instead of further dealing

Change-Id: I0a1ac4255344d1da7a21917ad559b9de4d5a4fee
Signed-off-by: Liu Changcheng <changcheng.liu@intel.com>
Signed-off-by: Jerry Liu <primerlink@gmail.com>
2017-04-06 22:47:00 +08:00
Josh Gao 8b951f5adc Merge changes Ib8369088,I743433bc
* changes:
  debuggerd_test: remove useless pipe.
  debuggerd_client: fix infinite timeouts.
2017-04-05 04:20:14 +00:00
Josh Gao 951cf70071 debuggerd_test: remove useless pipe.
Bug: http://b/36897117
Test: none
Change-Id: Ib8369088153fe44de2af9037299bdfce7b709b98
2017-04-04 14:09:04 -07:00
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 a5199a9e43 debuggerd_test: add test for process/thread names.
Make sure that we can get the process/thread names for nondumpable
processes with capabilities.

Bug: http://b/36237221
Test: /data/nativetest/debuggerd_test/debuggerd_test32
Change-Id: Iedd4eae18065c2e64abeebff15e3b9b09a630550
2017-04-03 13:18:34 -07:00
Josh Gao 352a84574d tombstoned: add tests for b/36685795.
Add some tests for edge cases which may have triggered b/36685795.

Bug: http://b/36685795
Test: debuggerd_test
Change-Id: I20670684c8dae422af157be21e44ba5d6d3214d3
2017-03-30 16:49:19 -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 807a45807b tombstoned: refactor request dequeuing a bit.
Also make it loop, so that upon failing to start a dequeued crash
request, we continue to the next one.

Bug: http://b/36685795
Test: debuggerd_test
Change-Id: I94889125f16f4681c6fa0fa9cac456302602ce01
2017-03-30 16:19:53 -07:00
Josh Gao 13078245a0 tombstoned: don't increment num_concurrent_dumps until success.
Previously, we would increment num_concurrent_dumps and fail to
decrement it if we failed to start the request. Change this to
only increment after we've successfully started the dump.

Bug: http://b/36685795
Test: debuggerd_test
Change-Id: I66169ed56ed44271e1d8fe1298d95260be7a32a3
2017-03-30 14:51:38 -07:00
Treehugger Robot 372d8a2931 Merge "debuggerd_client: properly wait for completion." 2017-03-28 03:21:39 +00:00
Josh Gao ae9d7676a5 debuggerd_client: properly wait for completion.
Use an intermediate pipe to detect and report when a requested dump has
completed.

Bug: http://b/35241370
Bug: http://b/35813071
Test: debuggerd_test
Test: manually triggered a background ANR
Change-Id: If14aedf6071288360f1a7853d5a2ee79db121759
2017-03-27 16:11:38 -07:00
Elliott Hughes f5d727f221 Merge ""Requested dump for tid XXX" message shouldn't be fatal." 2017-03-24 23:29:23 +00:00
Elliott Hughes 561da6aa82 "Requested dump for tid XXX" message shouldn't be fatal.
This just means we were asked to dump, not that something necessarily went
wrong.

Bug: http://b/36191903
Test: builds
Change-Id: I5638b38f3a13081b1e971512f43238010febb59c
2017-03-23 23:04:27 -07:00
Christopher Ferris 9642232f13 Initialize si_code in siginfo.
There was at least one failure due to si_code being unitialized
and then examined.

Test: Run the 32 bit and 64 bit version of the unit tests on angler.
Change-Id: I5455a2cd29afafcd26a49f696e61141bb48478dc
2017-03-22 18:06:57 -07:00
Christopher Ferris f5e568e653 Do not access device maps.
It's possible that a device map has memory controlled by a single entry
device driver. Thus, you can deadlock if a process is touching that
device memory and we try to unwind it and also touch that device memory.
Simply skip any attempts to step through, or get function names from
device memory maps.

Bug: 36130325

Test: Ran new unit tests, ran bionic unit tests, ran art ThreadStress.
Change-Id: Ibc62d7ec8106c619ee08968f05e04aea55d7cbfa
2017-03-22 14:55:05 -07:00
Josh Gao 7390d96ff2 Merge "crash_dump: fetch process/thread names before dropping privileges." 2017-03-16 17:45:18 +00:00
Josh Gao 57f58f8e4a crash_dump: fetch process/thread names before dropping privileges.
Processes that don't have dumpable set to 1 cannot have their
process/thread names read by processes that don't have all of their
capabilities. Fetch these names in crash_dump before dropping
privileges.

Bug: http://b/36237221
Test: debuggerd_test
Test: debuggerd -b `pidof android.hardware.bluetooth@1.0-service`
Change-Id: I174769e7b3c1ea9f11f9c8cbdff83028a4225783
2017-03-15 23:30:14 -07:00
Dan Willemsen e0cd1e043d Enable more modules on linux_bionic builds
Bug: 31559095
Test: Enable host bionic, run soong
Change-Id: Ib4ebd909322cf464b6a40040e4b60ece7d905b6f
2017-03-15 15:44:00 -07:00
Tom Cherry 5b4eb23cfd Remove extraneous .clang-format files
The .clang-format files in the base, debuggerd, adb, libprocinfo, and
fastboot subdirectories each differ slightly from the top level
.clang-format-2 and .clang-format-4, but not in a substantially
meaningful way, as the source files in those directories have not been
re-formatted with clang-format.  Therefore, let's reduce the
differences and use only the two top level clang-format files.

Secondly perform some small clean-up of the top level .clang-format
files.  AllowShortBlocksOnASingleLine is already false in the Google
style, so it can be removed.  AllowShortFunctionsOnASingleLine should
not change between the -2 and -4 versions, so leave it at the Google
default style in both, which is 'All'.

The diff stats for these changes are:

./base/
Old:
640 insertions(+), 531 deletions(-)
New:
563 insertions(+), 808 deletions(-)

./debuggerd/
Old:
910 insertions(+), 886 deletions(-)
New:
991 insertions(+), 1023 deletions(-)

./adb/
Old:
2623 insertions(+), 2886 deletions(-)
New:
2655 insertions(+), 3103 deletions(-)

./libprocinfo/
Old:
2 insertions(+), 1 deletion(-)
New:
4 insertions(+), 18 deletions(-)

./fastboot/
Old:
618 insertions(+), 743 deletions(-)
New:
726 insertions(+), 882 deletions(-)

./init/
Old:
1755 insertions(+), 1866 deletions(-)
New:
1715 insertions(+), 1952 deletions(-)

Test: Above clang-format stats
Change-Id: I3f7b8ab0660c8394c5008ba95ea15e70dd22b55b
2017-03-14 14:06:31 -07:00
Josh Gao c7fe0600cc crash_dump: fix warnings, turn on -Werror.
Test: mma
Change-Id: I0722fef7b513be976cbbe89f73e8bb7138a80442
2017-03-13 14:13:29 -07:00
Josh Gao 428daafc5b crash_dump: improve logging for when a process dies prematurely.
If a process that's getting dumped dies before crash_dump starts (e.g.
because seccomp immediately kills it after it execs crash_dump),
improve the error message to not just say "target died before we could
attach".

Bug: http://b/36077710
Test: inserted an exit in the handler, inspected output
Change-Id: I7d394c66d60d328b096b15654b3648e1ed711728
2017-03-10 14:52:34 -08:00
Josh Gao ec91809dae debuggerd_handler: restore errno.
Bug: http://b/31448909
Test: mma
Change-Id: I737d66e8bed5fb31c2558f68608d3df460fa73c9
2017-03-10 14:44:54 -08:00
Josh Gao 9eb4eb1811 libdebuggerd: add compatibility shim.
Avoid breaking internal code when AOSP automerges to internal.

This will be reverted after fixing up the uses on the other end.

Bug: http://b/35858739
Test: treehugger
Change-Id: If1ee03d8d7c218d3ad9f451cfe9a9077753dda02
2017-03-09 12:13:16 -08:00
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
Chenjie Luo 97258aad8a Define _LOG as a weak symbol.
So _LOG could be overridden by customized logging
implementations in non-Android systems.

Bug: 35919515
Test: Test on device
Change-Id: I0885c15353c0b1bf66f6f156e7f502f326b85d57
2017-03-06 15:04:32 -08:00
Treehugger Robot 56e89ade33 Merge changes Ib69a206f,If57cc175
* changes:
  tombstoned: turn off signal handlers.
  tombstoned: create tombstones with 0640 permissions.
2017-03-06 22:26:17 +00:00
Josh Gao 55f79a5953 tombstoned: turn off signal handlers.
Don't try to connect to ourselves in a signal handler (e.g. if someone
does `killall -ABRT tombstoned`).

Test: killall -ABRT tombstoned
Change-Id: Ib69a206f741acb523c9f2883d474c940b6ebfab2
2017-03-06 12:30:25 -08:00
Josh Gao 8830c95def tombstoned: create tombstones with 0640 permissions.
Make tombstones group readable to allow them to be picked up by the
dropbox service.

Bug: http://b/35979630
Test: killall -ABRT rild; dumpsys dropbox
Change-Id: If57cc17563c80d5b5c4887b0937905bffef6b231
2017-03-06 12:30:25 -08:00
Elliott Hughes 12b7129406 Small debuggerd improvements.
Include the ABI in seccomp causes.

Slightly improved command-line usage information.

Fix crasher for seccomp failures.

Bug: N/A
Test: crasher
Change-Id: Ie419ecfe72ee4f5ccf49c927be18350a58a66a90
2017-03-02 19:01:20 -08:00
Josh Gao b038995d29 Merge "debuggerd: remove obsolete dumpable check." 2017-03-01 22:59:01 +00:00
Josh Gao 981761bbb2 debuggerd: remove obsolete dumpable check.
PR_SET_DUMPABLE is ignored now.

Bug: http://b/35872161
Test: debuggerd -b `pidof surfaceflinger`
Change-Id: Iefd090f2b762d454d1e6ce8061ff5f992974267c
2017-03-01 11:55:16 -08:00
Elliott Hughes b7788fd454 There's no longer a limit to property names.
Bug: http://b/33926793
Test: boots
Change-Id: I8554d7af74e064c114cf817f5a2ba1247fa2a2db
2017-02-28 14:12:54 -08:00
Treehugger Robot 94aabe47db Merge "debuggerd_test: add capability test." 2017-02-17 21:20:11 +00:00
Josh Gao 502cfd22ba debuggerd_test: add capability test.
Also, remove the dependency on crasher.

Bug: http://b/35100921
Bug: http://b/35241370
Test: /data/nativetest/debuggerd_test/debuggerd_test32
Test: /data/nativetest64/debuggerd_test/debuggerd_test64
Change-Id: I318f6de764d435251417953bf175ba321b59981f
2017-02-17 11:22:21 -08:00
Elliott Hughes da9e3958d6 Add crasher check for passing a bad pthread_t to pthread_join.
Bug: http://b/35455349
Test: manual
Change-Id: If09454c7104a1e6de7c0edb50ee52118b7ca5eaa
2017-02-17 10:26:48 -08:00
Josh Gao 5ad965bf41 crash_dump: fix overflow.
`1 << 32` overflows, resulting in bogus PR_CAP_AMBIENT_RAISE attempts,
and breaking dumping for processes with capabilities in the top 32 bits.

Bug: http://b/35241370
Test: debuggerd -b `pidof com.android.bluetooth`
Change-Id: I29c45a8bd36bdeb3492c9f74599993c139821088
2017-02-16 20:16:58 -08:00
Josh Gao 2a18b822d5 crash_dump: remove unneeded/faulty checks.
We already check our /proc/`getppid()` fd every time we attach a thread, so
these were unneeded at best. The one that happened after dropping
capabilities was actively wrong, though, because /proc/pid access
checks happen on every operation. (only on some kernels?)

Also, add a check that getppid() doesn't change after opening
/proc/getppid().

Bug: http://b/35241370
Test: debuggerd -b `pidof com.android.bluetooth`
Change-Id: I807439d8c2afd027f3c382face50167a8a7946c4
2017-02-16 19:26:09 -08:00
Josh Gao c7cd48af58 Merge "libdebuggerd_handler: in-process crash dumping for seccomped processes." 2017-02-16 23:11:52 +00:00
Josh Gao a70f11331f Merge "crash_dump: make output fd O_APPEND." 2017-02-16 22:43:59 +00:00
Josh Gao e73c932373 libdebuggerd_handler: in-process crash dumping for seccomped processes.
Do an in-process unwind for processes that have PR_SET_NO_NEW_PRIVS
enabled.

Bug: http://b/34684590
Test: debuggerd_test, killall -ABRT media.codec
Change-Id: I62562ec2c419d6643970100ab1cc0288982a1eed
2017-02-15 17:03:44 -08:00
Josh Gao f6ad5851e6 crash_dump: fix typos in error messages.
Bug: http://b/34760032
Bug: http://b/35367169
Test: mm
Change-Id: I45fa002d4ca616a41524583228987ab1197a125e
2017-02-15 17:03:30 -08:00
Josh Gao 8a7e703912 crash_dump: make output fd O_APPEND.
Bug: http://b/35209835
Test: mma
Change-Id: I447e3cfa3361f9c8b4b3335d0abccd1fe4c98e0f
2017-02-15 16:25:27 -08:00
Josh Gao 60515bf9f1 debuggerd_handler: don't use snprintf in handler.
snprintf isn't safe to call in the linker after initialization, because
it uses MB_CUR_MAX which is implemented via pthread_getspecific, which
uses TLS slots shared with libc. If the TLS slots are assigned in a
different order between libc.so and the linker, MB_CUR_MAX will
evaluate to an incorrect value, and lead to snprintf doing bad things.

Switch to __libc_format_buffer.

Bug: http://b/35367169
Test: debuggerd -b `pidof zygote`
Change-Id: I9d315cf63e5f3fd2f4545d6e3f707cdbe94ec606
2017-02-15 12:24:09 -08:00
Josh Gao 2f11a25a48 debuggerd_handler: set PR_SET_DUMPABLE before running crash_dump.
Set and restore PR_SET_DUMPABLE when performing a dump, so that
processes that have it implicitly cleared (e.g. services that acquire
filesystem capabilities) still get crash dumps.

Bug: http://b/35174939
Test: debuggerd -b `pidof surfaceflinger`
Change-Id: Ife933c10086e546726dec12a7efa3f9cedfeea60
2017-02-14 21:19:38 -08:00
Josh Gao d2069632bd debuggerd_handler: raise capabilities before running crash_dump.
Raise CapInh and CapAmb after forking to exec crash_dump, so that it
can ptrace us.

Bug: http://b/35174939
Test: debuggerd -b `pidof surfaceflinger`
Change-Id: I32567010a3603cfa494aae9dc0e3ce73fb86b590
2017-02-14 14:40:47 -08:00
Josh Gao 91ad653c82 crasher: add a case that uses PR_SET_NO_NEW_PRIVS.
Bug: http://b/34684590
Test: crasher no_new_privs
Change-Id: I400d599116e3f3c27f5ea46d260e288cf900e156
2017-02-14 14:40:47 -08:00
Josh Gao c3c8c029ec debuggerd_handler: don't use waitpid(..., __WCLONE).
waitpid(..., __WCLONE) fails with ECHILD when passed an explicit PID to
wait for. __WALL and __WCLONE don't seem to be necessary when waiting
for a specific pid, so just pass 0 in the flags instead.

Bug: http://b/35327712
Test: /data/nativetest/debuggerd_test/debuggerd_test32 --gtest_filter="*zombie*"
Change-Id: I3dd7a1bdf7ff35fdfbf631429c089ef4e3172855
2017-02-13 17:01:24 -08:00
Josh Gao c24cc8a9e5 crash_dump: collect open files before dropping caps.
/proc/<pid>/fd is also limited by ptrace_may_access.

Test: manual inspection of "debuggerd -b `pidof zygote`"
Change-Id: I1a28c21c0438fe8729bd8e041c6b418d6a84c586
2017-02-07 13:36:08 -08:00
Josh Gao 7a0ee64f9d debuggerd_test: improve error when crasher fails to exec.
Bug: http://b/35100742
Test: rm /system/bin/crasher && /data/nativetest/debugerd_test/debuggerd_test32
Change-Id: I02faec3b7f7ef62bb8a2ac2af730506e3d28e03e
2017-02-07 13:36:08 -08:00
Josh Gao a7d7eb6d2a debuggerd_test: fix crasher path.
https://android-review.googlesource.com/#/c/331200 moved crasher to
using soong, which changed its location from /system/xbin/crasher to
/system/bin/crasher.

Bug: http://b/35100742
Test: /data/nativetest/debuggerd_test/debuggerd_test32
Test: /data/nativetest64/debuggerd_test/debuggerd_test64
Change-Id: I16a2050b257277023773cc0c960b5ab36e0c7cd4
2017-02-07 13:13:48 -08:00
Josh Gao 347164cc59 crash_dump: read /proc/<pid>/maps before dropping capabilities.
Reading /proc/<pid>/maps does a ptrace_may_access check, which will
fail if we have fewer capabilities than the target, even if we've
already ptraced it.

Bug: http://b/35070339
Test: debuggerd -b `pidof zygote`
Change-Id: I984a061022bd945a7950b88f6d579e1bd735e893
2017-02-07 12:35:51 -08:00
Josh Gao 54ef57d0b8 debuggerd_handler: fix prctl return value check.
Fixed this when I tested on internal, but failed to copy the fix over
when submitting to AOSP.

Bug: http://b/35070339
Test: `adb bugreport` on angler
Change-Id: Ib84d212e5f890958cd21f5c018fbc6f368138d1e
2017-02-06 21:10:48 -08:00
Josh Gao 279cb8b39a Merge changes from topic 'debuggerd_ambient'
* changes:
  debuggerd_handler: don't use clone(..., SIGCHLD, ...)
  crash_dump: drop capabilities after we ptrace attach.
  crash_dump: use /proc/<pid> fd to check tid process membership.
  debuggerd_handler: raise ambient capset before execing.
  Revert "Give crash_dump CAP_SYS_PTRACE."
2017-02-06 18:37:55 +00:00
Josh Gao b3ee52e4d0 debuggerd_handler: don't use clone(..., SIGCHLD, ...)
Processes that handle SIGCHLD can race with the crash handler to wait
on the crash_dump process. Use clone flags that cause the forked
child's death to not be reported via SIGCHLD, and don't bail out of
dumping when waitpid returns ECHILD (in case another thread is already
in a waitpid(..., __WALL))

Note that the use of waitid was switched to waitpid, because waitid
doesn't support __WCLONE until kernel version 4.7.

Bug: none
Test: "debuggerd -b `pidof zygote64`" a few times (failed roughly 50%
      of the time previously)
Change-Id: Ia41a26a61f13c6f9aa85c4c2f88aef8d279d35ad
2017-02-02 13:54:39 -08:00
Josh Gao 85bcaf68d3 crash_dump: drop capabilities after we ptrace attach.
Bug: http://b/34853272
Test: debuggerd -b `pidof system_server`
Test: debuggerd -b `pidof zygote`
Change-Id: Ic1e1a4b0eb1f561621800cd4cc9a5b848fc5ffd8
2017-02-02 13:54:38 -08:00
Josh Gao fe90276aee crash_dump: use /proc/<pid> fd to check tid process membership.
Bug: http://b/34759490
Test: /data/nativetest/debuggerd_test/debuggerd_test32
Test: debuggerd -b `pidof system_server`
Test: debuggerd -b `pidof zygote`
Change-Id: I627692b44977335a9568cd765ad28205f0a61327
2017-02-02 13:54:38 -08:00
Josh Gao 7ae426c731 debuggerd_handler: raise ambient capset before execing.
Raise the ambient capability set to match CapEff so that crash_dump can
inherit all of the capabilities of the dumped process to be able to
ptrace. Note that selinux will prevent crash_dump from actually use
any of the capabilities.

Bug: http://b/34853272
Test: debuggerd -b `pidof system_server`
Test: debuggerd -b `pidof zygote`
Change-Id: I1fe69eff54c1c0a5b3ec63f6fa504b2681c47a88
2017-02-02 13:54:38 -08:00
Elliott Hughes f4ae6203a9 Merge "Better seccomp/kuser_helper diagnostics from debuggerd." 2017-02-02 17:37:25 +00:00
Elliott Hughes 0ba535976f Better seccomp/kuser_helper diagnostics from debuggerd.
Also switch to Android.bp for crasher.

Bug: http://b/34629282 (seccomp)
Bug: http://b/34705831 (seccomp)
Bug: http://b/34884086 (kuser_helpers)
Test: manual
Change-Id: I8ee79c635518faeba751742919af69a505b5e3e1
2017-02-01 18:43:03 -08:00
Josh Gao 6462bb41e0 debuggerd_handler: add and use fatal_errno.
Bug: none
Test: mma
Change-Id: I24d913abdbe74f9463feda78f7817ca8b92af9cc
2017-01-31 14:59:05 -08:00
Josh Gao 1e4afb52c5 debuggerd: fix `debuggerd <pid>`
Bug: none
Test: `debuggerd mediaserver`
Change-Id: Ibd7bbddb92a99ce49622c0ecc9329a3723f2085d
2017-01-30 17:58:04 -08:00
Josh Gao b53f903cf1 debuggerd: fix `debuggerd -b <pid>`
Dump all of the threads when using `debuggerd -b`.

Bug: http://b/34719257
Test: `debuggerd -b mediaserver`
Change-Id: I2f57100985e5b0c2bf019482ba9feff31921692f
2017-01-30 17:58:04 -08:00
Josh Gao 4ed00c8d73 debuggerd_handler: improve nonfatal signal message.
"Fatal signal 35 (???)" -> "Requested dump for"

Bug: http://b/34809044
Test: debuggerd -b $$
Change-Id: I9ece0ee1117203d30142b843973ed7e5435e21da
2017-01-30 17:58:04 -08:00
Josh Gao e5288f292a debuggerd_handler: remove PR_SET_DUMPABLE check.
crash_dump has CAP_SYS_PTRACE and this was never obeyed by debuggerd.

Change-Id: Ifee5e94b97b1f6440ad0be79758f0db2d2aaba2e
2017-01-26 15:08:18 -08:00
Josh Gao 7e14d020f1 debuggerd_handler: don't dump PR_NO_NEW_PRIVS processes.
We can't do an selinux transition when this is on.

Bug: http://b/34472671
Test: logcat -c; debuggerd `pidof media.codec`; logcat
Change-Id: Ie6c1832ab838df48879c32a86126862de9a15420
2017-01-25 11:16:03 -08:00
Josh Gao 529b3066d5 debuggerd_handler: don't resend nonfatal signals when not dumping.
Bug: http://b/34516140
Test: debuggerd -b `pidof surfaceflinger`
Change-Id: I0275ffca24bf4840e264eaa4b79611e2404edfb0
2017-01-25 11:15:01 -08:00
Josh Gao 0a37901b9f crash_dump: properly dump when we can't talk to tombstoned.
Bug: http://b/32466479
Test: stop tombstoned; logcat -c; crasher; logcat
Change-Id: I16c010cc1865b4e1db8d2b85c904a2e074f28f1f
2017-01-24 15:22:43 -08:00
Vijay Venkatraman 5fe1cebe7c Merge "Replaced include log/logger.h with log/log.h in debuggerd" 2017-01-24 19:07:30 +00:00
Vijay Venkatraman a95acea5bf Replaced include log/logger.h with log/log.h in debuggerd
Test: Compile debuggerd
Change-Id: I33d12708993bd6818907b8cbb0a7a40672ad320d
2017-01-23 20:11:51 -08:00
Josh Gao 8498016b81 tombstoned: silence spurious error messages.
Bug: none
Test: booted after deleting /data/tombstones/*
Test: crasher creates a tombstone
Change-Id: I8b3e8a3b521952412ebc955b2437bf8150220c16
2017-01-23 16:01:14 -08:00
Josh Gao 0ad5107e51 Actually don't start tombstoned until /data is mounted.
Bug: http://b/34461270
Test: boot is actually faster
Test: tombstoned still started by init
Change-Id: I4976abef108bbb6fad264f9b68cbc1fba711085b
2017-01-23 16:01:14 -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 fca7ca3585 debuggerd_handler: properly crash when PR_GET_DUMPABLE is 0.
Actually exit when receiving a signal via kill(2) or raise(2) and
PR_GET_DUMPABLE is 0.

Bug: none
Test: /data/nativetest/debuggerd_test/debuggerd_test32
Test: /data/nativetest64/bionic-unit-tests/bionic-unit-tests --gtest_filter=pthread_DeathTest.pthread_mutex_lock_null_64
Change-Id: I833a2a34238129237bd9f953959ebda51d8d04d7
2017-01-23 14:13:36 -08:00
Josh Gao 7c6e3133f5 crash_dump: set a watchdog timer.
PTRACE_DETACH is only necessary if the process is in group-stop state,
the tracer exiting is sufficient to detach and resume tracees.

Using this, set a 5 second timer with alarm(2) that just kills us, to
avoid leaving processes stopped.

Bug: http://b/34472671
Test: debuggerd_test
Test: crasher + manually inserting a 10 second sleep into crash_dump
Change-Id: Iacaa796f79037aa1585f3f2159abe45ef0069311
2017-01-23 11:39:31 -08:00
Josh Gao 122479f4a0 crash_dump: switch to PTRACE_SEIZE.
ptrace(PTRACE_ATTACH) does not immediately put the traced process in a
stopped state. If we manage to call PTRACE_CONT on it before it
finishes, we'll fail. Switch to using PTRACE_SEIZE and PTRACE_INTERRUPT
to guarantee that the target stops immediately.

This also has the advantage of never putting the process in group-stop
state, which means if we exit prematurely (e.g. if we crash during
stack unwinding), the target process will be resumed without any
intervention needed.

Bug: http://b/34472671
Test: while true; do debuggerd -b `pidof audioserver`; done
Change-Id: I7549f67489646cf300b8c9aa8c735e5e897806ef
2017-01-23 11:34:49 -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 d20d687de5 crash_dump: remove extra log.
We're already aborting via LOG(FATAL), there's no reason to log again.

Bug: none
Test: mma
Change-Id: I96cb09b716b19381d6a6931048827ef45f87170b
2017-01-23 11:34:49 -08:00
Josh Gao b64dd85c94 debuggerd_handler: actually wait for pseudothread to exit.
Occasionally, the pseudothread wouldn't exit in time after unlocking
the mutex to get crash_dump to proceed, resulting in spurious error
messages. Instead of using a mutex to emulate pthread_join, just
implement it correctly.

Bug: http://b/34472671
Test: debuggerd_test
Change-Id: I5c2658a84e9407ed8cc0ef2ad0fb648c388b7ad1
2017-01-23 11:34:49 -08:00
Treehugger Robot b479a5002e Merge "init: don't start tombstoned until /data is mounted." 2017-01-20 22:13:38 +00:00
Josh Gao 42a0fed78b init: don't start tombstoned until /data is mounted.
When vold mounts the encrypted /data partition, it first checks for and
kills processes that have open fds to the tmpfs placeholder at /data.
This resulted in a 20 second boot-time regression (vold's timeout period)
when tombstoned was started before vold.

Bug: http://b/34461270
Test: boot is faster, no messages from vold in console spew
Test: tombstoned still started by init
Change-Id: Ib5e9ddb05f40c9da852f00e103861c6ff2d94888
2017-01-20 13:18:51 -08:00
Josh Gao ac0403b1e5 Merge "crash_dump: don't abort if we fail to attach a sibling." 2017-01-20 21:02:30 +00:00
Josh Gao 42fd74bd1f crash_dump: don't abort if we fail to attach a sibling.
A TOCTOU race can occur between listing threads and attaching them.
Don't abort and leave the process in a stopped state when this happens.

Bug: http://b/34472671
Test: while true; do debuggerd -b `pidof audioserver`; done
Change-Id: Ib1632c3423fddf506b5c7874223c82fada78a85e
2017-01-20 12:55:07 -08:00
George Burgess IV 7008c8484d Fix a call to openat with incorrect arguments
Caught by running clang-FORTIFY over Android.

Bug: None
Test: Builds
Change-Id: If138c4bbb7f5fb40bbb20e24adbb25a6ef1286ac
2017-01-19 13:33:52 -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
Mark Salyzyn 51c33b7011 liblog: use log/log.h for ALOG macros
Test: compile
Bug: 34250038
Change-Id: I0f56c563871f377c03380498cd867b916892f1dc
2017-01-12 15:44:06 -08:00
Mark Salyzyn 30f991f251 liblog: use log/log.h when utilizing ALOG macros
Test: compile
Bug: 30465923
Change-Id: Id6d76510819ebd88c3f5003d00d73a0dbe85e943
2017-01-11 09:31:15 -08:00
Elliott Hughes 400628aeac Improve crasher.
Make it behave better in our typical use cases and support more of the kinds
of crash we want to document.

Bug: http://b/28746168
Test: crasher
Change-Id: Ifbc3dfb042f6055568244c921f4abe1ea554cec4
2016-12-14 17:33:46 -08:00