Another release, another attempt to fix this bug.
This change affects pthread_detach, pthread_getcpuclockid,
pthread_getschedparam/pthread_setschedparam, pthread_join, and pthread_kill:
instead of returning ESRCH when passed an invalid pthread_t, they'll now SEGV.
Note that this doesn't change behavior as much as you might think: the old
lookup only held the global thread list lock for the duration of the lookup,
so there was still a race between that and the dereference in the caller,
given that callers actually need the tid to pass to some syscall or other,
and sometimes update fields in the pthread_internal_t struct too.
We can't check thread->tid against 0 to see whether a pthread_t is still
valid because a dead thread gets its thread struct unmapped along with its
stack, so the dereference isn't safe.
Taking the affected functions one by one:
* pthread_getcpuclockid and pthread_getschedparam/pthread_setschedparam
should be fine. Unsafe calls to those seem highly unlikely.
* Unsafe pthread_detach callers probably want to switch to
pthread_attr_setdetachstate instead, or using pthread_detach(pthread_self())
from the new thread's start routine rather than doing the detach in the
parent.
* pthread_join calls should be safe anyway, because a joinable thread won't
actually exit and unmap until it's joined. If you're joining an
unjoinable thread, the fix is to stop marking it detached. If you're
joining an already-joined thread, you need to rethink your design.
* Unsafe pthread_kill calls aren't portably fixable. (And are obviously
inherently non-portable as-is.) The best alternative on Android is to
use pthread_gettid_np at some point that you know the thread to be alive,
and then call kill/tgkill directly. That's still not completely safe
because if you're too late, the tid may have been reused, but then your
code is inherently unsafe anyway.
If we find too much code is still broken, we can come back and disable
the global thread list lookups for anything targeting >= O and then have
another go at really removing this in P...
Bug: http://b/19636317
Test: N6P boots, bionic tests pass
Change-Id: Ia92641212f509344b99ee2a9bfab5383147fcba6
Each release we're asked to investigate tombstones from code that hasn't
been allowed to run on Android since L. This is just wasting our time,
and clearly the "obviousness" of aborting rather than exiting hasn't ensured
that all app developers rebuild their old binaries. In some cases it seems
like they run them "just in case" and don't care if they fail.
Bug: http://b/34112178
Test: ran libsupervisor.so from com.ss.android.article.news
Change-Id: I8a3f196c4755601a3888281566fbb7b817f01dca
The crash happens because for static executables call to dlopen
results in crash. This change moves dlopen() == nullptr check
from static variable to a functions so that the dlopen crash only
affects tests calling dlopen but not the whole executable.
Also make static tests report crashes to debugerd
Test: run bionic-unit-tests-static (for arm 32 and 64)
Bug: http://b/34129417
Change-Id: I7c4d8caf2a43250234fe24496b1c95eab572769f
Don't allow processes to read the contents of the directory
/dev/__properties__. This is an implementation detail of the properties
system that processes shouldn't be concerned with.
Test: Device boots and no problems reading individual properties.
Test: ls -la /dev/__properties__ fails
Change-Id: I00130fe4529525935654bff91e3cc59253b86e26
For apps targeting pre-O releases print warn about
invalid dynamic section.
Bug: http://b/33842263
Test: Start an app in question and check logs for warning.
Test: Run bionic-unit-test --gtest_filter=dl*:Dl*
Change-Id: I80bd51f2133b956fc04e20a6538cccd50118c1b8
Stream-mode detection for L1 in A7-core is failing for
non cache-line-size (non 64 byte) aligned addresses.
This leads to destination data getting cached unnecessarily.
This A7 issue is confirmed by ARM
This issue is solved by aligning destination address to 64 byte before
entering the loop in memcpy routine.
Though we get lower score for micro_bench memcpy when L1 cache is bypassed,
it is desirable since it avoids unnecessary eviction of other process data
from L1 which is good for overall system performance.
Higher micro_bench memcpy numbers for < 64byte alignment shows good numbers
but this is at the cost of L1 cache pollution. During memcpy/memset,
unnecessary data is filled in L1 cache, this causes eviction of other
process data from L1.
For example during msmset(0), L1 cache gets filled with 0s which should be
avoided.
Additionally, there is another issue with cortex A7 that impacts performance
for all alignments / all Android Wear versions:
Store Buffer on A7 is 32 byte which limits the 32-byte back to back stores.
In the current implementation back to back 32bytes writes is causing CPU stalls.
This issue can be solved by interleaved Loads and Stores.
This helps in avoiding CPU stalls during memcpy by utilizing efficiently the
A7 internal load and store buffers.
Change-Id: Ie5f12f2bb5d86f627686730416279057e4f5f6d0
The followup for 4742abdcb5
Changes in this file got lost in the process of cherry-picking
the change across repositories.
Bug: http://b/29458203
Test: flash, set debug.ld.all to dlsym and check
if there are messages in logcat
Change-Id: I4613908e46e75c5d9ec66396767f10fc6d3e9777
280236537e factored the pthread types out
so that they could be in both <sys/types.h> and <pthread.h>.
Bug: N/A
Test: builds
Change-Id: Ie649c938ec8be1c59a0e4ef777f425550f8d4539
This adds CTS test for system libraries to support
workaround for http://b/24465209: some apps require
a subset of system libs to have elf-hash and not to
use packed relocations.
Bug: http://b/32917341
Bug: http://b/24465209
Test: bionic-unit-tests --gtest_filter=Dl*:dl*
Change-Id: Ia0bc28506b1f1f97d4cf902d73b0769e2815fed3
To support upcoming disk usage calculation optimizations, this change
creates a new GID for each app that will be used to mark its cached
data. We're allocating these unique GIDs so that we can use
quotactl() to track cached data on a per-app basis.
Test: builds, boots, tests pass
Bug: 27948817
Change-Id: Ic00c39ccedc23d5d43988029e9921679126f8f2d
Other C libraries don't have this, and it doesn't make sense on Android
anyway.
Bug: N/A
Test: builds
Change-Id: Iebc490698d620b5baec5f9a7ad5e1a0a1323d16c
Add dlsym option to debug.ld.all and debug.ld.app.<appname> which
enables logging of dlsym calls.
Bug: http://b/29458203
Test: flash, set debug.ld.all to dlsym and check
if there are messages in logcat
Change-Id: I9cb815a38b5b98aac9ebe3ac1540bcdedd2e8db0
This was introduced by d9e427cf41
where libdl.c android_dlwarning method implementation was
not updated.
This makes it delegate the call to ld-android.so
Bug: http://b/33530622
Test: build, flash and launch test app
Change-Id: I8a379442de94724280638db73e5f7934f2ea394e
