Commit graph

739 commits

Author SHA1 Message Date
Peter Collingbourne
939d074236 Fix CrasherTest.smoke in debuggerd_test.
Now that we default to sync MTE in tests, the default tagged_addr_ctrl
in this test needs to be updated.

Bug: 135772972
Change-Id: I9bf6fb29df9799d1ed8c0d8b66f4d2891f487d80
2021-02-02 19:00:48 -08:00
Evgenii Stepanov
2a55e1adbe Scale timeouts in debuggerd and llkd.
Respect ro.timeout_multiplier property. Some of these are required for
tombstone writing to work on MTE QEMU, the rest are done speculatively.

Test: add crashing code to system_server, observe the tombstone
Bug: 178231152
Change-Id: Ic86e494af571301df7af07d13a6c046a0da6bda7
2021-02-01 20:00:53 +00:00
Josh Gao
618cea3ebd Remove use of libbase logging in libdebuggerd.
libbase logging uses getprogname() to get the default tag, which breaks
for the fallback handler which is statically linked into the dynamic
linker. Switch to libasync_safe for logging.

Test: atest -c CtsSeccompHostTestCases:android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls
Change-Id: Ieeaf33fb26cff4ba7e1589d1d883ac2fcc74cf47
2021-01-27 15:52:43 -08:00
Josh Gao
76e1e30f16 Reland protobuf tombstones.
This reverts the following commits:
    e156ede145.
    eda96eddcb.
    5ec54d1e84.
    1e45d3f223.
    a50f61f8fa.

Test: treehugger
Test: atest -c CtsSeccompHostTestCases:android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls
Change-Id: Ic2b1f489ac9f1fec7d7a33c845c29891f4306bbd
2021-01-26 17:55:17 -08:00
Jerome Gaillard
e156ede145 Revert "tombstoned: switch from goto to RAII."
Revert "Let crash_dump read /proc/$PID."

Revert submission 1556807-tombstone_proto

Reason for revert: b/178455196, Broken test: android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls on git_master on cf_x86_64_phone-userdebug

Reverted Changes:
Ide6811297:tombstoned: switch from goto to RAII.
I8d285c4b4:tombstoned: make it easier to add more types of ou...
Id0f0fa285:tombstoned: support for protobuf fds.
I6be6082ab:Let crash_dump read /proc/$PID.
Id812ca390:Make protobuf vendor_ramdisk_available.
Ieeece6e6d:libdebuggerd: add protobuf implementation.

Change-Id: I8a77f6b9e1b42902ef7ee250cc3f1fd341ea0e2b
2021-01-26 12:42:09 +00:00
Jerome Gaillard
eda96eddcb Revert "tombstoned: make it easier to add more types of outputs."
Revert "Let crash_dump read /proc/$PID."

Revert submission 1556807-tombstone_proto

Reason for revert: b/178455196, Broken test: android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls on git_master on cf_x86_64_phone-userdebug

Reverted Changes:
Ide6811297:tombstoned: switch from goto to RAII.
I8d285c4b4:tombstoned: make it easier to add more types of ou...
Id0f0fa285:tombstoned: support for protobuf fds.
I6be6082ab:Let crash_dump read /proc/$PID.
Id812ca390:Make protobuf vendor_ramdisk_available.
Ieeece6e6d:libdebuggerd: add protobuf implementation.

Change-Id: Ib2403c1b61f6cf0513b76361440fbc5909d7554a
2021-01-26 12:42:03 +00:00
Jerome Gaillard
5ec54d1e84 Revert "tombstoned: support for protobuf fds."
Revert "Let crash_dump read /proc/$PID."

Revert submission 1556807-tombstone_proto

Reason for revert: b/178455196, Broken test: android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls on git_master on cf_x86_64_phone-userdebug

Reverted Changes:
Ide6811297:tombstoned: switch from goto to RAII.
I8d285c4b4:tombstoned: make it easier to add more types of ou...
Id0f0fa285:tombstoned: support for protobuf fds.
I6be6082ab:Let crash_dump read /proc/$PID.
Id812ca390:Make protobuf vendor_ramdisk_available.
Ieeece6e6d:libdebuggerd: add protobuf implementation.

Change-Id: I0c4f3a17e8b06d6c65255388c571ebf11d371dbb
2021-01-26 12:41:52 +00:00
Jerome Gaillard
1e45d3f223 Revert "libdebuggerd: add protobuf implementation."
Revert "Let crash_dump read /proc/$PID."

Revert submission 1556807-tombstone_proto

Reason for revert: b/178455196, Broken test: android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls on git_master on cf_x86_64_phone-userdebug

Reverted Changes:
Ide6811297:tombstoned: switch from goto to RAII.
I8d285c4b4:tombstoned: make it easier to add more types of ou...
Id0f0fa285:tombstoned: support for protobuf fds.
I6be6082ab:Let crash_dump read /proc/$PID.
Id812ca390:Make protobuf vendor_ramdisk_available.
Ieeece6e6d:libdebuggerd: add protobuf implementation.

Change-Id: Ia0a1ee57e7630e01c495dc166218f665340aad7f
2021-01-26 12:41:20 +00:00
Jerome Gaillard
a50f61f8fa Revert "Fix build breakage."
This reverts commit 675cb30f05.

Reason for revert: b/178455196, Broken test: android.seccomp.cts.SeccompHostJUnit4DeviceTest#testAppZygoteSyscalls on git_master on cf_x86_64_phone-userdebug

Change-Id: I82d228f2bc3e6b426d4703732e1c8766815ccc97
2021-01-26 12:40:51 +00:00
Josh Gao
675cb30f05 Fix build breakage.
Test: mma
Test: treehugger
Change-Id: I2d08c9b6e7776e69ca1e7f0d83838830f3c9b15c
2021-01-25 15:11:49 -08:00
Josh Gao
6bf6a9fc61 Merge changes from topic "tombstone_proto"
* changes:
  libdebuggerd: add protobuf implementation.
  tombstoned: support for protobuf fds.
  tombstoned: make it easier to add more types of outputs.
  tombstoned: switch from goto to RAII.
2021-01-25 22:18:48 +00:00
Mitch Phillips
1d792bf90a Merge "[MTE] Cleanup tagged si_addr refs to fix mappings OOB bug." 2021-01-25 17:20:40 +00:00
Mitch Phillips
e4adff0721 [MTE] Cleanup tagged si_addr refs to fix mappings OOB bug.
Currently, all MTE failures end up displaying 'Fault address falls at
0x<addr> after any mapped regions'. Clearly when scanning, we should use
the untagged address to figure out which ranges it's in.

I've taken the liberty of removing all si_addr parsing and moving it
into the common ProcessInfo, as well as making it really explicit
whether you want the (possibly tagged) original si_addr, or whether you
want the untagged variant (for scanning /proc/maps or whatever).

This is not particularly easily testable, as ReadCrashInfo isn't easily
injectable and `dump_all_maps` should already be passed the untagged
pointer to scan for. I've tested this locally on FVP under SYNC MTE with
a simple UaF binary and noted the problem is fixed. Given that this is
making the code more clear, I'm hoping the owners see no need for a
regression test :).

Bug: 135772972
Test: On FVP, run 'adb shell MEMTAG_OPTIONS=sync sanitizer-status' and
      check that the use-after-free test ends up with the /proc/maps
      desription in the right place.
Change-Id: I220e4200c75a72474a95a67e5bbc36173a438dd2
2021-01-21 20:49:06 -08:00
Josh Gao
92317d82c9 libdebuggerd: add protobuf implementation.
This commit implements protobuf output for tombstones, along with a
translator that should emit bytewise identical output to the existing
tombstone dumping code, except for ancillary data from GWP-ASan and
Scudo, which haven't been implemented yet.

Test: setprop debug.debuggerd.translate.translate_proto_to_text 1 &&
        /data/nativetest64/debuggerd_test/debuggerd_test
Test: for TOMBSTONE in /data/tombstones/tombstone_??; do
        pbtombstone $TOMBSTONE.pb | diff $TOMBSTONE -
      done
Change-Id: Ieeece6e6d1c26eb608b00ec24e2e725e161c8c92
2021-01-21 15:40:23 -08:00
Elliott Hughes
d8af5b5e4f Remove unnecessary #includes.
Sadly, it looks like we do still really use libcutils for some of the
socket functions.

Test: treehugger
Change-Id: Ic71f97507c89b10d2f3b7a2971064a9e6b1d349d
2021-01-19 09:21:52 -08:00
Elliott Hughes
03b283a65f Move debuggerd_test over to mallopt().
Bug: http://b/135772972
Test: treehugger
Change-Id: I178f2a753b5608d9e72cee8874524ad4faf701d7
2021-01-15 11:34:26 -08:00
Josh Gao
1091d24c16 tombstoned: support for protobuf fds.
Test: debuggerd_test
Change-Id: Id0f0fa2856e4b8e57d7dc0e1495134e943b289da
2021-01-13 13:35:45 -08:00
Josh Gao
e2aa621c83 tombstoned: make it easier to add more types of outputs.
While we're at it, switch to unlinkat.

Test: debuggerd_test
Change-Id: I8d285c4b4e94effa1acb8f69ac3af4ff8c37defb
2021-01-13 13:35:45 -08:00
Josh Gao
9a61f685d8 tombstoned: switch from goto to RAII.
Test: debuggerd_test
Change-Id: Ide6811297bf59776619aac6ed96653ae5cc84040
2021-01-13 13:35:45 -08:00
Peter Collingbourne
cd27807bfe Remove ANDROID_EXPERIMENTAL_MTE.
Now that the feature guarded by this flag has landed in Linux 5.10
we no longer need the flag, so we can remove it.

Bug: 135772972
Change-Id: I02fa50848cbd0486c23c8a229bb8f1ab5dd5a56f
2021-01-11 10:55:51 -08:00
Christopher Ferris
6ddc2c56c9 Update for v5.10 kernel headers.
Test: Builds.
Change-Id: I6c4b04751df026ef7cbb91627174188c5e6d137c
2020-12-14 22:36:37 -08:00
David Srbecky
8efcd6325c Adjust to MapInfo to new api.
Change-Id: Ic3818a8b001657e6b54ba6fcbf68f8c1d7ef2683
2020-11-24 17:27:05 +00:00
Peter Collingbourne
48c35f0cf6 Merge "Change the android_mallopt(M_SET_HEAP_TAGGING_LEVEL) API." 2020-11-18 20:57:36 +00:00
Peter Collingbourne
71ad49554f Change the android_mallopt(M_SET_HEAP_TAGGING_LEVEL) API.
- Make it apply to every thread, and thus remove the restriction
  that it must be called while the program is single threaded.
- Make it change TCF0 itself (on all threads), instead of requiring
  callers to do it themselves, which can be error prone.

And update all of the call sites.

Change the implementation of
android_mallopt(M_DISABLE_MEMORY_MITIGATIONS) to call
android_mallopt(M_SET_HEAP_TAGGING_LEVEL) internally. This avoids
crashes during startup that were observed when the two mallopts
updated TCF0 unaware of each other.

I wouldn't expect there to be any out-of-tree callers at this point,
but it's worth noting that the new interface is backwards compatible
with the old one because it strictly expands the set of situations in
which the API can be used (i.e. situations where there are multiple
threads running or where TCF0 hadn't been updated beforehand).

Bug: 135772972
Change-Id: I7746707898ff31ef2e0af01c4f55ba90b72bef51
2020-11-18 10:24:29 -08:00
Peter Collingbourne
ebc78cc852 Switch to the new kernel API for obtaining fault address tag bits.
The discussion on LKML is converging on v16 of the fault address tag
bits patch [1]. In this version of the patch the presence of the tag
bits in si_addr is controlled by a sa_flags bit, and a protocol is
introduced to allow userspace to detect kernel support for sa_flags
bits. Update the tombstone signal handler to use this API to read
the tag bits, update the interceptors in libsigchain to implement
the flag support detection protocol and hide the tag bits in si_addr
from chained signal handlers that did not request them to match the
kernel behavior.

[1] https://lore.kernel.org/linux-arm-kernel/cover.1605235762.git.pcc@google.com/

Change-Id: I57f24c07c01ceb3e5b81cfc15edf559ef7dfc740
2020-11-13 16:08:27 -08:00
Treehugger Robot
485505c06d Merge "Fix the expected tagged_addr_ctrl in a test." 2020-11-03 03:12:02 +00:00
Peter Collingbourne
2b6764a625 Fix the expected tagged_addr_ctrl in a test.
It turns out that I had originally written the test with a local
patch applied that forces TCF0 to SYNC, so it was testing for the
wrong tagged_addr_ctrl value. Fix it.

Bug: 135772972
Change-Id: Ibb9b25e5f5635372ad5de7825c31d7264ff02590
2020-11-02 16:00:08 -08:00
Yifan Hong
2ec92cfc28 libdebuggerd_handler_fallback: make vendor_ramdisk_available.
Test: builds
Bug: 156098440
Change-Id: I11466de73bbb3a30c10a7a9088954e37772b7a00
2020-10-28 10:57:51 -07:00
Josh Gao
81c94cdce6 Start tombstoned early in post-fs-data.
Bug: http://b/169659307
Test: manual
Change-Id: Ie19de31e7e2b6cd43402cfd3a2e9274728e9e6b4
2020-10-01 14:25:36 -07:00
Treehugger Robot
d0642a373d Merge "Improve error message in debuggerd fallback handler." 2020-10-01 21:00:16 +00:00
Josh Gao
68083003b8 Improve error message in debuggerd fallback handler.
Bug: http://b/164014625
Test: none
Change-Id: I4f1e61be93c511676e66b909a15735bba963eff0
2020-09-25 13:51:02 -07:00
Christopher Ferris
b05c472421 Add arch member into Unwinder object.
This simplifies some of the logic and removes the need to pass an
Arch value to functions that should already know about the arch
it is operating on.

Includes fixes for debuggerd/libbacktrace.

Added new unit tests to cover new cases.

Test: All unit tests pass.
Test: Faked unwinder failing to verify debuggerd error messages display
Test: properly in backtrace and tombstone.
Change-Id: I439fcae0695befcfb1cb4c0a786cc74949d33425
2020-09-24 18:46:23 -07:00
Peter Collingbourne
864f15dd6d Dump the per-thread TAGGED_ADDR_CTRL value if available.
This value indicates whether memory tagging is enabled on a thread,
the mode (sync or async) and the set of excluded tags. This information
can sometimes be important for understanding an MTE related crash,
so include it in the per-thread tombstone output.

Bug: 135772972
Change-Id: I25a16e10ac7fbb2b1ab2a961a5279f787039000b
2020-09-15 21:32:36 -07:00
Elliott Hughes
713ec25103 libdebuggerd: do a to-do.
Until 77fdb22cf6, logd started as
AID_ROOT and then dropped its privileges. Since then, there's been no
reason to use string comparisons rather than checking the uid.

Test: pkill -SEGV logd
Test: treehugger
Change-Id: Ia709f8f59cb0ab9abac7df84c96c701b5d0a83ea
2020-08-03 18:56:35 +00:00
Jeff Sharkey
7b21637782 Update language to comply with Android's inclusive language guidance
See https://source.android.com/setup/contribute/respectful-code for reference

Bug: 161896447
Change-Id: Iafcccbdbdf3ff1078e87000e2ce560ff09b43f68
2020-07-31 16:36:06 -06:00
Elliott Hughes
ba1bd64ca2 Merge "debuggerd: use One True timestamp function." 2020-07-24 15:47:03 +00:00
Elliott Hughes
a660cb3f13 debuggerd: use One True timestamp function.
An OEM asks for sub-second granularity, and that's most easily done if
we only have one timestamp generator. I'm not convinced sub-second
granularity is particularly useful myself, and I definitely don't think
that nanosecond resolution is meaningful but I do like this cleanup, and
if I'm going to use sub-second precision I may as well use the maximum
precision available to me.

Also reduce some duplication of code reading cmdline/comm.

Bug: https://issuetracker.google.com/161860597
Test: head /data/tombstones/*
Change-Id: I035ecfd4a3338ccd84dae0ef973a998a7c7c5056
2020-07-23 16:33:53 -07:00
Peter Collingbourne
fe8997aff8 Include memory tags in memory dump output.
Tags appear in the addresses printed in the memory dump, which seems
like a reasonable place to put them because tagged addresses will
also appear in other places in the tombstone, such as registers and
the fault address.

Bug: 135772972
Change-Id: I52da338347ff6b7503cf5ac80763c540695dc061
2020-07-21 19:05:16 -07:00
Peter Collingbourne
b1fcedb928 Adjust conditions for dumping the memory around a register.
Previously, we would do a simple bounds check before deciding
whether to dump the memory around a register. On 64-bit platforms,
the register's value was required to be less than (4 << 60). However,
after stripping tags on AArch64 as part of r.android.com/1365229, all
pointer values became less than (4 << 60), so the check became useless
for filtering out invalid pointers. As a result, we would attempt to
dump memory for all registers, which for a register not containing
a valid pointer would typically consist of 16 lines of dashes.

One possible fix may be to replace the constant (4 << 60) with the
process's actual address space limit (known as TASK_SIZE inside the
kernel; typically 39 bits on AArch64 and 48 bits on x86_64), but the
kernel provides no API for retrieving a process's TASK_SIZE value. We
could guess it by looking at for example the highest bit set in the
value of getauxval(AT_EXECFN), which points to an address on the stack
which typically is mapped at the end of the address space on program
startup, but at least on AArch64 it is possible to dynamically extend
TASK_SIZE at runtime by providing a hint to mmap(), so this is not
always sufficient.

Instead, it seems best to remove most of the early bounds check, and
simply issue ptrace() calls for each register value, bailing out of
the entire output if none of the calls ended up succeeding. This also
has the nice side effect of avoiding 16 lines of noise per register
whose value looks like a pointer but actually points to unmapped
memory. We still retain part of the bounds check in order to avoid
integer overflow during the dump (including overflows into the tag
part of the address on architectures that support tagging).

Bug: 154272452
Change-Id: I94e4b7124b7735b92fd83a49c80ebded3483cd4e
2020-07-21 16:59:24 -07:00
Peter Collingbourne
d00a577c97 Statically link libminijail to debuggerd_test.
We do not install a 32-bit version of libminijail to 64/32 devices,
which means that "atest -a debuggerd_test" always fails on 32-bit.
Fix it by statically linking libminijail.

Change-Id: I1e5610d1353b4f5b718c1259825421c0c07d7c24
2020-07-21 16:59:24 -07:00
Peter Collingbourne
10e428dd77 Fix dumping of heap memory.
After r.android.com/1288984 we started failing to dump memory contents
for heap addresses because the tag started causing any addresses to
fail this bounds check. Add an untag_address() call to the bounds check
so that the tag is ignored.

Bug: 154272452
Change-Id: I3a6d1a078b21871bd93164150a123549f83289f6
2020-07-17 17:35:49 -07:00
Peter Collingbourne
bbe6905d7e Add stack trace coverage to MTE tests.
It's impractical to test the contents of the stack trace, but we
should at least test that *a* stack trace is present, which would
have caught the bug fixed by r.android.com/1306754 .

Bug: 135772972
Change-Id: Ic5e0b997caa53c7eeec4e5185df5c043c9d4fe3d
2020-05-08 10:14:47 -07:00
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
Tom Cherry
c5c6d7d326 Don't include log/log_read.h in log/log.h
log/log.h primarily concerns itself with writing logs.  The few users
who read logs should directly include log/log_read.h.

Bug: 78370064
Test: build
Change-Id: Ie95c55ea2ffc76fc95768323d445ada6ad4f2520
2020-04-17 15:31:34 -07:00
Josh Gao
c40a7515eb debuggerd: don't leave a zombie child if crash_dump is killed.
If crash_dump dies before it gets a chance to write to the pipe we use
to let the debugged-process know that it successfully started, we
weren't cleaning up the child we fork to start it, leaving a zombie
child.

Bug: http://b/152119184
Test: debuggerd_test
Change-Id: Id01cc05f693995e9998941774f74ab8e3d8b4d8a
2020-04-10 10:09:39 -07:00
Peter Collingbourne
cd63cae6b2 Merge "Read fault address on arm64 using proposed kernel API." 2020-03-30 21:40:58 +00:00
Peter Collingbourne
5677803cb7 Merge "Create a debugger_process_info data structure with the process info pointers." 2020-03-30 21:36:41 +00:00
Peter Collingbourne
e2b76c5b00 Merge "Move crash_dump into the runtime APEX." 2020-03-30 19:03:41 +00:00
Peter Collingbourne
f03af8844a Read fault address on arm64 using proposed kernel API.
On aarch64, the top 8 bits of the address (i.e. the tag bits) of
the fault address in si_addr are always clear. This isn't ideal for
MTE which will require these bits in order to correctly diagnose
tag mismatches.

A proposed kernel patch [1] exposes the full fault address including
the tag bits as part of the ucontext. Change debuggerd to read this
fault address if available.

[1] https://patchwork.kernel.org/patch/11435077/

Bug: 135772972
Change-Id: Ia05be574113860f4e9ecc36a310c4b740e0c4afb
2020-03-27 20:00:06 -07:00
Mitch Phillips
b9c072c551 Move PC-only unwind frame generation to libunwindstack.
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
2020-03-26 13:39:05 -07:00