Commit graph

352 commits

Author SHA1 Message Date
Tom Cherry
cbb09bcbb1 Merge "Always use CLOCK_MONOTONIC for pthreads and semaphores" 2017-08-18 19:59:26 +00:00
Tom Cherry
ac49cedc7e Always use CLOCK_MONOTONIC for pthreads and semaphores
pthread's and semaphore's default behavior is to use CLOCK_REALTIME,
however this behavior is essentially never intended, as that clock is
prone to change discontinuously.

What users really intend is to use CLOCK_MONOTONIC, however only
pthread_cond_timedwait() provides this as an option and even there, a
large amount of existing code does not opt into CLOCK_MONOTONIC.

We have seen numerous bugs directly attributable to this difference.
Therefore, we provide this general workaround to always use
CLOCK_MONOTONIC for waiting, regardless of what the input timespec
is.

Specifically this impacts the below APIs:
pthread_mutex_timedlock()
pthread_cond_timedwait()
pthread_rwlock_timedrdlock()
pthread_rwlock_timedwrlock()
sem_timedwait()

Test: boot bullhead, boot sailfish
Test: bionic pthread/semaphore unit tests
Test: check that pthread_cond_timedwait() timeouts are uneffected by
      CLOCK_REALTIME time changes

Bug: 64694413
Bug: 64623895
Bug: 35756266
Bug: 35678943
Change-Id: Ibba98f5d88be1c306d14e9b9366302ecbef6d534
2017-08-18 09:11:05 -07:00
Evgenii Stepanov
abb163f5f0 Revert "Revert "arm64: expand CFI shadow to cover 48-bit virtual addresses""
This reverts commit ea3df0c52b, and
increases the address limit on non-aarch64 64-bit platforms as well.

RLIMIT_AS problem fixed in a different commit.

Bug: 63141434, 64293803
Test: device boots
Change-Id: I1284c4196cc1f0c9d97c3ced97a19de328050d21
2017-08-03 14:11:28 -07:00
Elliott Hughes
c41b560f5f Implement wcwidth(3) in terms of icu4c.
Based on com.google.i18n.CharWidth by the icu-team folks.

Bug: N/A
Test: ran tests
Change-Id: Ia9d818ec4ae60f2f3978533195330d00699397c5
2017-07-27 17:08:24 -07:00
Elliott Hughes
697f42afdb Hide various mbstate implementation details.
...by inlining them.

Also fix a couple of harmless bugs in passing. I've added tests, but in
both cases I don't think it was actually possible to hit the bad behavior:
we'd hit another test and fail immediately after in an externally
indistinguishable way.

Bug: N/A
Test: readelf
Change-Id: I8466050b0bfe2b7b94c76b383cf10c1d9d28debd
2017-07-14 17:00:05 -07:00
Elliott Hughes
ea3df0c52b Revert "arm64: expand CFI shadow to cover 48-bit virtual addresses"
This reverts commit ae735163e5.

QA claims this causes:

  AndroidRuntime: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.media.MediaPlayer.setSurface(android.view.Surface)' on a null object reference
  AndroidRuntime:        at com.android.setupwizardlib....

Bug: http://b/63141434
Change-Id: I05a6849471623d4cde8b254b1020b0ccbd84b699
2017-06-29 23:48:43 +00:00
Kevin Brodsky
ae735163e5 arm64: expand CFI shadow to cover 48-bit virtual addresses
Starting from Linux 4.7, arm64's defconfig enables 48-bit VAs, see:
https://git.kernel.org/torvalds/c/211102d8

On arm64, the CFI shadow configuration currently assumes that VAs
are 39-bit long, and as expected this results in a segfault on a
(defconfig) 4.7+ kernel, when linking a CFI-enabled library.

Consequently, this change increases the max target address to
account for the new max VA size.

Change-Id: I3fb808563fa77a457c65e9663da0613117332072
2017-06-28 14:42:05 +01:00
Goran Ferenc
996f6decfa MIPS: 32/64-bit VDSO support
File libc/SYSCALLS.TXT is updated to generate bionic's system call wrappers
for clock_gettime() & gettimeofday() that will be called if kernel vdso
implementations fail to execute.
The system call wrappers are generated using a python script gensyscalls.py.

Since all architectures support vdso now, there is no more need for conditional
statements regarding supported architectures in libc/bionic/vdso.cpp &
libc/private/bionic_vdso.h files.

Test: builds
Change-Id: I7213f29c179a7929851499d78a72900638ae861a
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
2017-06-01 08:50:57 -07:00
Christopher Ferris
a1c0d2fd4c Add support for modifying decay timer.
Add the mallopt function, and only a single option so far.

Bug: 36401135

Test: Built and booted bullhead.
Test: Ran jemalloc unit tests.
Test: Ran bionic unit tests.
Test: Ran a test that allocated and free'd a large piece of memory,
Test: and verified that after changing the parameter, the PSS
Test: sticks around (decay timer set to 1), the PSS is purged (decay
Test: timer set to 0).
Change-Id: I6927929b0c539c1023d34772d9e26bb6a8a45877
2017-05-15 16:59:16 -07:00
Christopher Ferris
7a3681e5b6 Move libc_log code into libasync_safe.
This library is used by a number of different libraries in the system.
Make it easy for platform libraries to use this library and create
an actual exported include file.

Change the names of the functions to reflect the new name of the library.

Run clang_format on the async_safe_log.cpp file since the formatting is
all over the place.

Bug: 31919199

Test: Compiled for angler/bullhead, and booted.
Test: Ran bionic unit tests.
Test: Ran the malloc debug tests.
Change-Id: I8071bf690c17b0ea3bc8dc5749cdd5b6ad58478a
2017-05-03 08:50:43 -07:00
Elliott Hughes
e4ddb3c587 Move bionic_systrace.cpp over to CachedProperty.
This is the last bionic caller that was manually trying to cache
property values.

Bug: N/A
Test: builds and boots
Change-Id: Id66c0a05d8448f08c39dbf7189241e75615d44b4
2017-04-17 14:12:25 -07:00
Treehugger Robot
ff82ce8746 Merge "Remove the useless lock from CachedProperty." 2017-04-12 05:59:57 +00:00
Elliott Hughes
a98aa56f33 Remove the useless lock from CachedProperty.
Also document that the caller should provide locking at an
appropriate scope.

Bug: N/A
Test: ran tests
Change-Id: Ib84802fd8b9dbe69f98feab80edef05549a3f73e
2017-04-11 17:23:37 -07:00
Tom Cherry
c40af334c7 Merge "Move scopeguard into android::base" 2017-04-06 22:41:02 +00:00
Elliott Hughes
9e27e58faa Add support for disabling the greylist.
Useful for testing whether apps have actually stopped using greylisted
libraries even if they still have references to them in their apk to support
old Android releases but also haven't bumped their targetSdkVersion yet.

Since we already have two expensive __system_property_get calls and this
would add a third, optimize two (but leave the third since it's not
obviously amenable to optimization). None of this matters for user builds,
but I don't want userdebug/eng to have distractingly different performance.

(cherrypick of 7933bec2872aa1c3430149c7649726333c0ac9d8.)

Bug: http://b/36106661
Test: ran "can you escape 5" with and without this property
Change-Id: Id9a804695c1dca9b4be2ebd0e72f01817bb13cba
2017-04-06 10:59:24 -07:00
Tom Cherry
b8ab61804c Move scopeguard into android::base
Test: boot bullhead, bionic unit tests
Change-Id: I223249684867655ecb53713b10da41d3014f96ae
2017-04-05 16:37:07 -07:00
Josh Gao
1c864b630f Merge "Break android_set_abort_message out of libc_logging." 2017-04-04 00:40:40 +00:00
Josh Gao
10ec9286ae Break android_set_abort_message out of libc_logging.
libc_logging is getting statically linked into the crash handler
library, resulting in two copies of the abort message code existing in
processes, one in the linker, and one in the crash handler.

Move android_set_abort_message to its own file to solve this.

Bug: http://b/36862204
Test: /data/nativetest/debuggerd_test/debuggerd_test32
Change-Id: Ie198c5a3bb07645aa43296915c9a6752693f14a9
2017-04-03 16:00:10 -07:00
Josh Gao
6367f5ee55 Merge changes I826756d9,I00e2edb2
* changes:
  libc_logging: mention that they're async signal safe.
  linker: update dependencies.
2017-04-03 20:33:18 +00:00
Dimitry Ivanov
2a4a5e72f1 Add end() method to bionic's ScopedTrace class
Bug: http://b/27195126
Test: make
Change-Id: I8243629200606ca87b11cbd479ca093add42eb56
2017-03-20 12:45:55 -07:00
Josh Gao
c17e5a4650 libc_logging: mention that they're async signal safe.
Test: none
Change-Id: I826756d9338e80f1dd16bd650eb89892bcbbb850
2017-03-08 21:31:48 -08:00
Dimitry Ivanov
6391e1a44d libc: __system_property_set uses writev to write atomically
__system_property_set sometimes produces broken_pipe error
when trying to write a property.

This change improves error messages and uses writev() instead
of sequence of send() calls.

Bug: http://b/35381074
Test: bionic-unit-tests --gtest_filter=prop*
Change-Id: I7a5b169c015db4e6b720370e58662de8206d1086
2017-02-24 14:00:04 -08:00
Josh Gao
5e2285d3cc Allocate thread local buffers in __init_tls.
Thread local buffers were using pthread_setspecific for storage with
lazy initialization. pthread_setspecific shares TLS slots between the
linker and libc.so, so thread local buffers being initialized in a
different order between libc.so and the linker meant that bad things
would happen (manifesting as snprintf not working because the
locale was mangled)

Bug: http://b/20464031
Test: /data/nativetest64/bionic-unit-tests/bionic-unit-tests
      everything passes
Test: /data/nativetest/bionic-unit-tests/bionic-unit-tests
      thread_local tests are failing both before and after (KUSER_HELPERS?)
Test: /data/nativetest64/bionic-unit-tests-static/bionic-unit-tests-static
      no additional failures
Change-Id: I9f445a77c6e86979f3fa49c4a5feecf6ec2b0c3f
2017-02-22 16:05:03 -08:00
Josh Gao
273991cead Add __libc_format_buffer_va_list.
Bug: http://b/35367169
Test: m
Change-Id: I133f231d3b93bdef56d06497679320a89c7188a9
2017-02-15 16:10:37 -08:00
Evgenii Stepanov
0a3637d3eb Runtime support for CFI
Control Flow Integrity support in bionic.

General design:
http://clang.llvm.org/docs/ControlFlowIntegrityDesign.html#shared-library-support

This CL implements subsections "CFI Shadow" and "CFI_SlowPath" in the above document.

Bug: 22033465
Test: bionic device tests
Change-Id: I14dfea630de468eb5620e7f55f92b1397ba06217
2017-01-18 13:13:52 -08:00
Elliott Hughes
722d01a991 Fix icu4c calling on x86.
Some of the function pointer types were wrong, and x86 cares if you
say `int` when you meant `int8_t` (because it feels at liberty to
leave the top bits dirty and ignore them, both sides need to agree
which they're dealing with).

Also slightly improve the wcstoimax and wcstoumax tests, since my
investigation started there.

Bug: http://b/33451822
Test: tests pass on x86, arm, and arm64
Change-Id: I553193962f0cb993666f9f8e415990bba5b669e1
2016-12-08 15:16:37 -08:00
Josh Gao
585fc3e554 Add __libc_arc4random_unlimited_entropy.
Let the caller know when libc has an entropy source and arc4random is safe.
This is useful for the callers that want entropy, but don't absolutely need it.

Bug: http://b/27729263
Test: booted angler-userdebug w/ safestack
Change-Id: Iab3050bd19f23518e1676629573eebc656ba1090
2016-11-29 15:26:08 -08:00
Elliott Hughes
a57ca0da69 Use icu4c to implement <wctype.h>.
Pretty useless, because the POSIX APIs are useless for actually
internationalization, but it lets us put this to bed for good.

Bug: http://b/18492914
Test: bionic tests
Change-Id: I4dd0aff66c44b5547039be3ffea806c865b9014a
2016-11-29 19:19:30 +00:00
Josh Gao
a170d9bfc5 Revert "Revert "Attempt to use arc4random where getauxval(AT_RANDOM) is used.""
This reverts commit 60d052dda6.

Bug: http://b/27729263
Change-Id: I7f32dc9f9a1f21fda3213f10da940821e1bdd63f
2016-11-10 17:02:45 -08:00
Dimitry Ivanov
e6ee960aef Replace .align with .balign for clarity
Test: run bionic-unit-tests
Change-Id: Icb43cc47e41d58fe3cb71986e05b3134022f895c
2016-10-27 05:11:56 -07:00
Josh Gao
b36efa4343 Fix instances of '#if __LP64__'.
Triggers -Wundef, which is on in -Weverything.

Bug: http://b/31496165
Change-Id: Ib06107073f7dd1d584c19c222d0430da9d35630b
2016-09-15 14:21:28 -07:00
Josh Gao
60d052dda6 Revert "Attempt to use arc4random where getauxval(AT_RANDOM) is used."
This reverts commit 78a52f19bb.

Change-Id: Ia72501ad0b81e894d67e5ce59b597397c11acfa5
2016-09-02 05:48:11 +00:00
Josh Gao
78a52f19bb Attempt to use arc4random where getauxval(AT_RANDOM) is used.
When arc4random can get entropy (which is true for basically everyone
but init on kernels that don't support getrandom), use it instead of
AT_RANDOM.

Bug: http://b/29622562
Change-Id: I6932803af2c477e65562ff531bd959f199fad1df
2016-08-31 18:01:05 -07:00
Elliott Hughes
1291e50173 Remove bionic's now-unused UniquePtr.
Change-Id: Id77dbdd6d4255ae8317449725ef093be9422407f
2016-07-22 19:52:46 -07:00
Treehugger Robot
4f62c5b311 Merge changes I7718b1ba,I648adc35
* changes:
  Only initialize the global stack protector once.
  Make getpid work before TLS has been initialized.
2016-07-22 19:20:58 +00:00
Evgenii Stepanov
d13e9a603f Align-up and randomize shared libraries.
This change implements the following property:
  Any 2**N aligned memory region on size 2**N contains no more than one DSO.

The value N can be configured, with 16 or 18 looking like a good choice.
Additionally, DSOs are loaded at random page-aligned address inside these large
regions.

This change has dual purpose:
1. Larger values of N allow a lot more compact CFI shadow implementation.
   See change I14dfea630de468eb5620e7f55f92b1397ba06217.
   For example, CFI shadow for the system_server process has the following size (RSS, KB):
   152 for N = 12, 32 for N = 16, 16 for N = 18.
2. Extra randomization is good for security.

This change does not result in extra RAM usage, because everything is still page-aligned.
It does result in a bit more VM fragmentation because of the gaps between shared libraries.
As it turns out, this fragmentation is barely noticeable because the kernel creates new mapping
at the highest possible address, and we do enough small mappings to almost completely fill the
gaps (ex. in the Zygote the gaps are filled with .ttf file mappings and thread stacks).

I've measured VM fragmentation as the sum of all VM gaps (unmapped regions) that are larger
than 1MB according to /proc/$PID/maps. On aosp_angler-userdebug, the numbers are (in GB):

                |   N = 12  |  N = 18
system_server   |   521.9   |  521.1
zygote64        |   522.1   |  521.3
zygote32        |   2.55    |  2.55
mediaserver     |   4.00    |  4.00

Change-Id: Ia6df840dd409c82837efd1f263be420d9723c84a
2016-07-19 18:18:22 -07:00
Elliott Hughes
4ce902c30e Support 32-bit ARM vdso.
Linux 4.1 added this.

Bug: http://b/19198045
Change-Id: I28be802ff403a61dd6733a001411b3ff05fef5a5
2016-07-12 13:55:51 -07:00
Elliott Hughes
53420fb21e x86-64's va_list is not a pointer type.
Change-Id: I680feeb641d5411ac481daaae6fa1580e74c5563
2016-06-30 13:47:16 -07:00
Josh Gao
b6453c52ac Only initialize the global stack protector once.
Before, dynamic executables would initialize the global stack protector
twice, once for the linker, and once for the executable. This worked
because the result was the same for both initializations, because it
used getauxval(AT_RANDOM), which won't be the case once arc4random gets
used for it.

Bug: http://b/29622562
Change-Id: I7718b1ba8ee8fac7127ab2360cb1088e510fef5c
Test: ran the stack protector tests on angler (32/64bit, static/dynamic)
2016-06-30 12:58:32 -07:00
Elliott Hughes
8ed118db61 Apparently mips and x86's va_list is a pointer type.
And clang won't let you have a function declaration where some arguments
have nullability specifiers and others don't.

Change-Id: I450b0221a3f7f068d5fe971dfbc0ba91d25710e8
2016-06-30 12:46:21 -07:00
Elliott Hughes
9eb3ae122f Remove __nonnull (in favor of _Nonnull).
It's a dangerous pain in the ass, and we're only using it in one place, and
that's a mistake too.

Change-Id: Ida1d1286aaa1343bdee95fa092fcb45ff3258f77
2016-06-30 10:37:03 -07:00
Josh Gao
c80ffece02 Defer registration of the arc4random fork-detect handler.
Previously, arc4random would register a fork-detecting pthread_atfork
handler to not have to call getpid() after a fork. pthread_atfork uses
pthread_mutex_lock, which requires the current thread to be initialized,
preventing the use of arc4random for initializing the global stack guard,
which needs to happen before the main thread has been initialized.

Extract the arc4random fork-detection flag and use the existing
arc4random fork handler to set it.

Bug: http://b/29622562
Change-Id: I98c9329fa0e489c3f78cad52747eaaf2f5226b80
2016-06-28 15:52:59 -07:00
Elliott Hughes
b0da5760dc Move the IEEE fp header out of the public headers.
Bug: http://b/28519060
Change-Id: I9f1a1a9ac1f22462bf86991b57c51824cb42eefd
2016-05-02 12:44:41 -07:00
Josh Gao
26bc9c64d5 Move <sys/_sigdefs.h> and <sys/_errdefs.h> to private.
Bug: http://b/28067717
Change-Id: I02f78ad7293a15ff45e35e9c20f60d3d023931eb
2016-04-13 17:45:39 -07:00
Elliott Hughes
5db4b6e5de Make it harder to use a broken legacy function by accident.
This function only exists for backwards compatibility, so leave it as it was.

Bug: http://b/26944282
Change-Id: I31973d1402660933103ee2d815649ab9569e4dfc
2016-04-04 16:15:37 -07:00
Mingwei Shi
be91052932 libc: implement kernel vdso syscalls for i386
This patch uses __kernel_vsyscall instead of "int 0x80"
as the syscall entry point. AT_SYSINFO points to
an adapter to mask the arch specific difference and gives a
performance boost on i386 architecture.

Change-ID: Ib340c604d02c6c25714a95793737e3cfdc3fc5d7
Signed-off-by: Mingwei Shi <mingwei.shi@intel.com>
2016-03-25 14:10:05 -07:00
Elliott Hughes
fc69a8ad5f Improve and fix the stack-protector tests.
Bug: http://b/26888853
Change-Id: I505dbf7d5934f7247fb639f55dd6a9341df3947b
2016-03-09 14:50:03 -08:00
Elliott Hughes
b83d6747fa Improve FORTIFY failure diagnostics.
Our FORTIFY _chk functions' implementations were very repetitive and verbose
but not very helpful. We'd also screwed up and put the SSIZE_MAX checks where
they would never fire unless you actually had a buffer as large as half your
address space, which probably doesn't happen very often.

Factor out the duplication and take the opportunity to actually show details
like how big the overrun buffer was, or by how much it was overrun.

Also remove the obsolete FORTIFY event logging.

Also remove the unused __libc_fatal_no_abort.

This change doesn't improve the diagnostics from the optimized assembler
implementations.

Change-Id: I176a90701395404d50975b547a00bd2c654e1252
2016-02-26 22:06:17 -08:00
Colin Cross
2c75991359 Add backtrace_string and export to libmemunreachable
Add backtrace_string to convert a malloc_debug backtrace to a string.
Also move the backtrace functions to libc_malloc_debug_backtrace so that
libmemunreachable can reuse them.

Change-Id: I5ad67001c0b4d184903c762863a8588181d4873b
2016-02-18 16:09:17 -08:00
Colin Cross
869691c6f7 Export malloc_iterate and friends
Export malloc_iterate, malloc_enable, and malloc_disable to be used by
libmemunreachable.

Change-Id: I08a50349af82a95d096b6b4cbac37ababe4b9b06
2016-02-18 15:05:38 -08:00