Commit graph

534 commits

Author SHA1 Message Date
Josh Gao
7596250722 Move fdtrack APIs to LLNDK.
Test: logcat -c; fdtrack_test; logcat -d
Change-Id: Ib6f75a7c8bbc4d6efa0708dcbbfe4ad3c0641022
2020-01-30 13:55:10 -08:00
Josh Gao
97271920bf Add a tool to track down fd leaks.
Add a hook that's called upon file descriptor creation to libc, and a
library that uses it to capture backtraces for file descriptor creation,
to make it easier to hunt down file descriptor leaks.

Currently, this doesn't capture all of the ways of creating a file
descriptor, but completeness isn't required for this to be useful as
long as leaked file descriptors are created with a function that is
tracked. The primary unhandled case is binder, which receives file
descriptors as a payload in a not-trivially-parsable byte blob, but
there's a chance that the leak we're currently trying to track down
isn't of a file descriptor received over binder, so leave that for
later.

Bug: http://b/140703823
Test: manual
Change-Id: I308a14c2e234cdba4207157b634ab6b8bc539dd9
(cherry picked from commit b7eccd4b15)
2020-01-30 13:55:10 -08:00
Mitch Phillips
3b21ada5f1 Add tagged pointers to bionic.
This patch introduces tagged pointers to bionic. We add a static tag to
all pointers on arm64 compatible platforms (needs requisite
top-byte-ignore hardware feature and relevant kernel patches).

We dynamically detect TBI-compatible devices (a device with the TBI feature and
kernel support) at process start time, and insert an implementation-dependent
tag into the top byte of the pointer for all heap allocations. We then check
that the tag has not been truncated when deallocating the memory.

If an application incorrectly writes to the top byte of the pointer, we
terminate the process at time of detection. This will allow MTE-incompatible
applications to be caught early.

Bug: 135754954
Bug: 147147490

Test: cd bionic && atest .
Change-Id: Ie424325ba1e3c4443040ac265aeaa28d9e405d28
2020-01-23 10:37:24 -08:00
Nicolas Geoffray
5c9efd1d66 Merge "Revert "Add tagged pointers to bionic."" 2020-01-21 13:57:45 +00:00
Nicolas Geoffray
ce4c42e09f Revert "Add tagged pointers to bionic."
This reverts commit 43d5f9d4dd.

Bug: 135754954
Bug: 147147490

Exempt-From-Owner-Approval: clean revert

Reason for revert: Breaks ART gtest, see:
https://ci.chromium.org/p/art/builders/ci/angler-armv8-non-gen-cc/561

The crash happens on mprotect of a page, the test crashes with ENOMEM.

Change-Id: I52eea1abbfaf8d8e2226f92d30aa55aba3810528
2020-01-21 13:57:26 +00:00
Mitch Phillips
3460b6c265 Merge "Add tagged pointers to bionic." 2020-01-20 23:31:27 +00:00
Mitch Phillips
43d5f9d4dd Add tagged pointers to bionic.
This patch introduces tagged pointers to bionic. We add a static tag to
all pointers on arm64 compatible platforms (needs requisite
top-byte-ignore hardware feature and relevant kernel patches).

We dynamically detect TBI-compatible devices (a device with the TBI feature and
kernel support) at process start time, and insert an implementation-dependent
tag into the top byte of the pointer for all heap allocations. We then check
that the tag has not been truncated when deallocating the memory.

If an application incorrectly writes to the top byte of the pointer, we
terminate the process at time of detection. This will allow MTE-incompatible
applications to be caught early.

Bug: 135754954
Bug: 147147490

Test: cd bionic && atest .
Change-Id: I6e5b809fc81f55dd517f845eaf20f3c0ebd4d86e
2020-01-15 15:03:00 -08:00
Ryan Savitski
175c8867b0 allow for heapprofd's signal to be multiplexed
This patch refactors heapprofd_malloc to make it easier to reuse the
reserved signal for multiple purposes. We define a new generic signal
handler for profilers, which dispatches to more specific logic based on
the signal's payload (si_value).

The profiler signal handler is installed during libc preinit, after
malloc initialization (so races against synchronous heapprofd
initialization need not be considered). In terms of code organization, I
copied the existing approach with a loosely referenced function in
bionic_globals.h. Do tell if you'd rather a different approach here.

The profileability of a process is quite tied to the malloc
files/interfaces in bionic - in particular, it's set through
android_mallopt. I do not change that, but instead introduce a new
android_mallopt option to be able to query profileability of the
process (which is now used by the new profiler signal handler). As part
of that, gZygoteChildProfileable is moved from heapprofd_malloc to
common (alongside gZygoteChild).

I've removed the masking and reraising of the heapprofd signal when
racing against malloc_limit init. We're ok with taking a simpler
approach and dropping the heapprofd signal in such an unlikely race.

Note: this requires a corresponding change in heapprofd to use sigqueue()
instead of kill(), as the latter leaves the si_value uninitialized(?) on
the receiving side.

Bug: 144281346
Change-Id: I93bb2e82cff5870e5ca499cf86439860aca9dfa5
2020-01-15 22:55:03 +00:00
Josh Gao
5074e7d28f Move sigrtmin.h into platform headers.
Test: mma
Change-Id: Ibc97ef96fe9e32b948c245b06039b95fe4342f39
2020-01-02 14:14:15 -08:00
Josh Gao
4956c372cf Move bionic_macros.h from private to platform.
Test: treehugger
Change-Id: Ie473914f4c8924c7240b3ac22093a9daf42fc948
2020-01-02 14:09:50 -08:00
Elliott Hughes
cdb52fc147 Make private/bionic_page.h available as platform/bionic/page.h.
Bug: http://b/145825270
Test: treehugger
Change-Id: I52958f370c0df2c02cb8250e2cf0705d4e93e908
2019-12-12 15:26:14 -08:00
Christopher Ferris
6f517cd7a1 Rename iterate to malloc_iterate internally.
I have no idea why I used the iterate name internally which is
completely unlike every other function name. Change this to match
everyone else so that it's now malloc_iterate everywhere.

This is probably the last chance to change this before mainline
modules begin, so make everything consistent.

Test: Compiles, unit tests passes.
Change-Id: I56d293377fa0fe1a3dc3dd85d6432f877cc2003c
2019-11-08 11:49:14 -08:00
Christopher Ferris
7a3a5d8cd7 Merge "Fix allocations escaping malloc debug." 2019-11-06 23:31:33 +00:00
Christopher Ferris
ff88fb0d3a Fix allocations escaping malloc debug.
When using a FILE object for some malloc debug functions, calling
fprintf will trigger an allocation to be put in the object. The problem
is that these allocations were not allocated by the malloc debug
wrapper and they get freed during the fclose as if they are malloc
debug allocation. In most cases, the code will detect the bad pointer
and leak the memory, but it might also cause a crash.

The fix is to avoid using fprintf so that no allocations are made
in the object that survive and need to be freed in the fclose call.

Change the MallocXmlElem.h to use a file decsriptor not a FILE object.

Add new unit and system tests to detect this case.

Bug: 143742907

Test: Ran unit and system tests.
Test: Ran bionic unit tests.
Change-Id: I524392de822a29483aa5be8f14c680e70033eba2
2019-11-06 10:42:42 -08:00
Johan Harvyl
89b09198b9 Close descriptor in ScopeFd destructor
The underlying descriptor is supposed to be closed when the ScopedFd
goes out of scope but due to a typo in reset() that never happens.

This change was inspired by an earlier implementation of ScopedFd in:
04dc91ae7 Load library using file handle.

Issue: 143918215
Test: Manual (verify fd usage on device)
Change-Id: I5664fa82d3e732113732e34a7ae6df3ca79d3cee
2019-11-05 12:20:23 +01:00
Elliott Hughes
6cb70ad776 Add the ScopedFd that we've never quite gotten around to.
This is actually for the new change I'm working on, but let's retrofit
it first to separate any bugs in these changes from those in the new
change...

Test: treehugger
Change-Id: I890aeb61f9792810a77ad0da3f9674c9cc5db7bb
2019-10-31 21:16:18 -07:00
Peter Collingbourne
900d07d6a1 Add arm64 string.h function implementations for use with hardware supporting MTE.
As it turns out, our "generic" arm64 implementations of certain string.h
functions are not actually generic, since they will eagerly read memory
possibly outside of the bounds of an MTE granule, which may lead to a segfault
on MTE-enabled hardware. Therefore, move the implementations into a "default"
directory and use ifuncs to select between them and a new set of "mte"
implementations, conditional on whether the hardware and kernel support MTE.

The MTE implementations are currently naive implementations written in C
but will later be replaced with a set of optimized assembly implementations.

Bug: 135772972
Change-Id: Ife37c4e0e6fd60ff20a34594cc09c541af4d1dd7
2019-10-29 16:18:31 -07:00
Peter Collingbourne
e949195f64 Adopt GNU calling convention for ifunc resolvers.
In order for an ifunc resolver to detect the presence of certain CPU features,
access to getauxval(AT_HWCAP) or getauxval(AT_HWCAP2) may be required. In order
for getauxval() to work, it needs to access the pointer to the auxiliary vector
stored by the linker in the libc shared globals data structure. Accessing the
shared globals requires libc to call the __libc_shared_globals() function
exported by the linker. However, in order to call this function, libc must
be fully relocated, which is not guaranteed to be the case at the point when
ifunc resolvers are called.

glibc solves this problem by passing the values of getauxval(AT_HWCAP)
(and getauxval(AT_HWCAP2) on aarch64) as arguments to the ifunc resolver.
Since this seems to be not only the most straightforward way to solve the
problem but also improves our compatibility with glibc, we adopt their
calling convention.

This change is ABI compatible with old resolvers because the arguments are
passed in registers, so the old resolvers will simply ignore the new arguments.

Bug: 135772972
Change-Id: Ie65bd6e7067f0c878df3d348c815fda61dc12de2
2019-10-28 20:20:29 -07:00
Christopher Ferris
c5d3a4348a Make tls related header files platform accessible.
There are places in frameworks and art code that directly included
private bionic header files. Move these files to the new platform
include files.

This change also moves the __get_tls.h header file to tls.h and includes
the tls defines header so that there is a single header that platform
code can use to get __get_tls and the defines.

Also, simplify the visibility rules for platform includes.

Bug: 141560639

Test: Builds and bionic unit tests pass.
Change-Id: I9e5e9c33fe8a85260f69823468bc9d340ab7a1f9
Merged-In: I9e5e9c33fe8a85260f69823468bc9d340ab7a1f9
(cherry picked from commit 44631c919a)
2019-09-27 12:14:24 -07:00
Elliott Hughes
fa43309a59 Merge "ifuncs: start sharing." 2019-09-18 18:01:54 +00:00
Elliott Hughes
a4c7876c01 ifuncs: start sharing.
We're going to have to add ifuncs to libm, and there will be some SVE
ones for arm64 soon too, so let's start sharing the absolute minimum...

Test: builds
Change-Id: Idbb9dd9477291ed3c15dc3902f65e593b766dfb9
2019-09-17 12:44:41 -07:00
Christopher Ferris
2b0638ef29 Make bionic_malloc.h a platform header.
Instead of having platform directories directly include the
private header, create a platform header directory and export it.

Bug: 130763340

Test: Builds.
Change-Id: Ie0f092b3fe077a3de8b90266c0b28bfbc20d0dfa
Merged-In: Ie0f092b3fe077a3de8b90266c0b28bfbc20d0dfa
(cherry picked from commit 8f582ef2f8)
2019-09-16 12:27:33 -07:00
Ryan Savitski
9db3486a12 Add arm32 case to BIONIC_STOP_UNWIND to correctly stop unwinders
The arm32 case was omitted when the macro was originally added due to
clang issues (b/15469122#comment5).

Testing at ToT master, ".cfi_undefined r14" appears to compile & work as
expected. This is the same directive as used by the linker's begin.S.

Test: ran a 32 bit binary on crosshatch-userdebug, verified that
"debuggerd -b" (which uses libunwindstack) stops at __libc_init as in
the arm64 case (before it would unwind past _start_main, with an
erroneous frame at the bottom).

Test: ran unwind_reg_info tool on /system/lib/libc.so with an address
within __libc_init, confirmed that the "debug_frame" section includes
"r14 = undefine" (arm exidx still contains "r14 = [cfa - 4]", but that
looked correct to cferris@).

Bug: 140008396
Change-Id: I6eb0bc6cf516fddee2df40492350678a0547fee3
2019-08-27 22:50:21 +01:00
Peter Collingbourne
191ecdc49b Fix a few bionic test failures caused by hwasan global instrumentation.
The call to the load hook needs to be moved before the call to link_image()
because the latter calls ifunc resolvers which might access global
variables. This fixes a bunch of ifunc tests.

The dlfcn.segment_gap test is currently failing. One problem is that the name
of the .bss.end_of_gap section changes as a result of global instrumentation.
Add some wildcards in so that we match both names. The other problem seems
to be the same as b/139089152.

It turns out that we need to untag pointers in a few more places. Since we have
quite a few of these now it seems worth creating a function for it.

Test: bionic-unit-tests
Change-Id: I44e2b0904faacdda7cc0c5e844ffc09de01dea2d
2019-08-15 09:21:34 -07:00
Peter Collingbourne
6533208aaa linker: Add library load and unload hooks for HWASan.
These hooks notify the HWASan runtime library whenever a library is loaded
or unloaded so that it can update its shadow memory.

Bug: 138159093
Test: walleye_hwasan-userdebug boots with+without https://reviews.llvm.org/D65770
Change-Id: I6caf2a6540ed2c0d94db444e806a3c7ba504cabb
2019-08-05 16:51:01 -07:00
Florian Mayer
6883b0807b Reserve signal for java heap dumps.
We will put instrumentation in ART to write out Java heap memory
information on receipt of this signal.

Bug: 136210868
Test: Flash blueline-userdebug and boot

Change-Id: I63173a4051c46b8569faaf3064e1db1dbd0ea3fe
2019-07-23 16:38:00 +01:00
Peter Collingbourne
45f0a3b642 Clear pointer tags as required for HWASAN for globals.
A future version of HWASAN will set pointer tags when taking the address of
a global. This means that we need to untag pointers in a couple of cases
where potential global pointers are passed to an interface that expects
untagged pointers:

- The WriteProtected class, whose only instances are globals, passes its
  own address to mprotect. However, our device kernels do not currently
  untag pointers passed to mprotect (the proposed upstream kernel patches
  do, however, untag these pointers), so once HWASAN starts tagging global
  pointers, this will start failing.
- The shadow_load function loads from a shadow that corresponds to the
  address space bounds of loaded binaries. Since these address space
  bounds are untagged, the pointer needs to be untagged to match.

Test: boots
Change-Id: I3f11ce6eb7261752e5ff6d039d04dd45516b236f
2019-07-16 13:38:38 -07:00
Elliott Hughes
5c6a3f9fbc libnetd_client: support hooking sendto/sendmsg/sendmmsg too.
Samsung has asked for this for KNOX.

Test: treehugger
Change-Id: Iffaace9f8cb265ce8c911472989c9829cbf91a42
2019-06-20 08:32:24 -07:00
Christopher Ferris
31fe3c637e Merge "Move all leak info functions to android_mallopt." 2019-04-23 17:45:01 +00:00
Ryan Prichard
f32e1a1f50 Merge "Comment about lock destruction and unlocking" 2019-04-22 21:09:44 +00:00
Ryan Prichard
aca110173f Comment about lock destruction and unlocking
Add a couple of comments explaining that a mutex can be freed during
the unlock call, immediately after the unlock's atomic exchange call but
before its futex wakeup call.

Bug: http://b/129744706
Test: bionic unit tests
Change-Id: I2d290ebde880f46866098d022720896039e7022e
2019-04-19 17:16:25 -07:00
Christopher Ferris
30659fd243 Move all leak info functions to android_mallopt.
Bug: 130028357

Test: malloc_hooks unit tests.
Test: Enable backtrace for mediaserver, run dumpsys media.player -m
Test: Enable backtrace for calendar, run am dumpheap -n <PID> <FILE>
Change-Id: I6774e28ccd9b3f2310127a5b39ccd15fe696a787
Merged-In: I6774e28ccd9b3f2310127a5b39ccd15fe696a787
(cherry picked from commit 3aadc5e80a)
2019-04-19 11:27:02 -07:00
Christopher Ferris
8189e77bbb Remove gMallocLeakZygoteChild.
Remove this global variable and change the setting of it to non-zero
to a call to android_mallopt.

In addition, change the initialize function to use pass a bool* instead of
int*.

Bug: 130028357

Test: Ran malloc_debug/malloc_hooks/perfetto tests.
Change-Id: I20d382bdeaaf38aac6b9dcabea5b3dfab3c945f6
Merged-In: I20d382bdeaaf38aac6b9dcabea5b3dfab3c945f6
(cherry picked from commit 5225b342f0)
2019-04-16 11:22:06 -07:00
Elliott Hughes
5493ddcaa2 Merge "Workaround potential access to unmapped stack" 2019-04-04 19:47:52 +00:00
Adrian-CJ Hung
8c1a14d4f3 Workaround potential access to unmapped stack
Issue:
Process is crashed near the end (startup_handshake_lock.unlock()) in
pthread_create().

The newly created child thread passes this handshake_lock unexpectedly
=> its stack is unmapped & its associated pthread_internal_t data
structure can’t be accessed.

Analysis:
The created child thread should be blocked by startup_handshake_lock.lock()
and enter __futex_wait_ex()

But if the parent thread is in the middle of startup_handshake_lock.unlock():

  void unlock() {
    if (atomic_exchange_explicit(&state, Unlocked, memory_order_seq_cst) == LockedWithWaiter) {  // => the state is modified to Unlocked

    // (a) if the child thread is back to running and pass the while() check in Lock::lock()
    // (b) the child thread executes its start_routine and then pthread_exit
    // (c) the stack of the child thread (where its pthread_internal_t (so the startup_handshake_lock) is located) will be unmapped

     __futex_wake_ex(&state, process_shared, 1);   // => when the parent thread is back to running
                                                   // the “state” & “process_shared” of startup_handshake_lock can’t be accessed (unmapped)
                                                   // so the process will be crashed
    }
  }

Bug: 129744706
Test: Monkey
Change-Id: I55175e8c7ebc2b3b52de8a5602def0667076b974
2019-04-03 11:50:33 +08:00
Pirama Arumuga Nainar
3e742cb613 Merge "Reserve realtime signal for libprofile-extras" 2019-03-29 15:57:32 +00:00
Pirama Arumuga Nainar
ebe1ae7747 Reserve realtime signal for libprofile-extras
Bug: http://b/128524141

This signal is used by libprofile-extras to trigger flush of gcov
coverage data.

Test: libprofile-extras in system/extras/toolchain-extras
Change-Id: I77dd5b1d67371a9cfaad54ad60254bfb2dd18ba9
2019-03-25 22:09:19 -07:00
Elliott Hughes
886370c240 Fix internal uses of _PATH_BSHELL.
We regressed on this recently: code under the upstream-* directories has
_PATH_BSHELL defined as a call to __bionic_get_shell_path(). In our own
code, we may as well just call it directly.

Bug: https://issuetracker.google.com/129030706
Test: ran tests
Change-Id: Ic2423f521272be95e67f94771772fe8072636ef0
2019-03-25 17:28:22 -07:00
Peter Collingbourne
b62888b709 Merge "Increase the size of the shadow call stack guard region to 16MB." 2019-03-19 23:29:05 +00:00
Christopher Ferris
1fc5ccfe76 Add a platform API for setting an allocation limit.
Introduce an M_SET_ALLOCATION_LIMIT enumerator for android_mallopt(),
which can be used to set an upper bound on the total size of all
allocations made using the memory allocation APIs.

This is useful for programs such as audioextractor and mediaserver
which need to set such a limit as a security mitigation. Currently
these programs are using setrlimit(RLIMIT_AS) which isn't exactly
what these programs want to control. RLIMIT_AS is also problematic
under sanitizers which allocate large amounts of address space as
shadow memory, and is especially problematic under shadow call stack,
which requires 16MB of address space per thread.

Add new unit tests for bionic.

Add new unit tests for malloc debug that verify that when the limit
is enabled, malloc debug still functions for nearly every allocation
function.

Bug: 118642754
Test: Ran bionic-unit-tests/bionic-unit-tests-static.
Test: Ran malloc debug tests and perfetto integration tests.
Change-Id: I735403c4d2c87f00fb2cdef81d00af0af446b2bb
2019-03-15 10:54:55 -07:00
Christopher Ferris
6c619a0da3 Refactor the malloc_info code.
malloc_info needs to be per native allocator, but the code treated it
like a global function that doesn't depend on the native memory allocator.

Update malloc debug to dump the actual pointers that it has been tracking.

Test: bionic-unit-tests pass.
Test: malloc debug tests pass.
Test: malloc hook tests pass.
Change-Id: I3b0d4d748489dd84c16d16933479dc8b8d79013e
Merged-In: I3b0d4d748489dd84c16d16933479dc8b8d79013e
(cherry picked from commit a3656a98b1)
2019-03-07 08:39:55 -08:00
Ryan Prichard
808d176e7e Merge "Fix linker self-exec detection" 2019-02-08 22:33:11 +00:00
Ryan Prichard
1990ba5601 Fix linker self-exec detection
When the linker is invoked on itself, (`linker64 /system/bin/linker64`),
the linker prints an error, because self-invocation isn't allowed. The
current method for detecting self-invocation fails because the second
linker instance can crash in a constructor function before reaching
__linker_init.

Fix the problem by moving the error check into a constructor function,
which finishes initializing libc sufficiently to call async_safe_fatal.
The only important thing missing is __libc_sysinfo on 32-bit x86. The aux
vector isn't readily accessible, so use the fallback int 0x80.

Bug: http://b/123637025
Test: bionic unit tests (32-bit x86)
Change-Id: I8be6369e8be3938906628ae1f82be13e6c510119
2019-02-07 21:48:42 -08:00
Christopher Ferris
62e1e2c7e3 Modify malloc common function pointers.
Instead of every function being its own atomic, have a single
pointer that can be used to flip all pointers at once. This avoid cases
where the set of pointers can be in an partial switched state.

Also fix a few inconsistent naming of functions in the file.

Test: Ran unit tests (malloc debug, malloc hooks, perfetto).
Change-Id: I3f66da395414586a3fa87874d80dcdf5f702ed39
Merged-In: I3f66da395414586a3fa87874d80dcdf5f702ed39
(cherry picked from commit 77184aedaf)
2019-02-07 14:48:34 -08:00
Peter Collingbourne
f1ed31ffe1 Increase the size of the shadow call stack guard region to 16MB.
Increasing the size of the guard region helps with the security of SCS,
but it's blocked on landing [1], which in turn is blocked on landing
[2]. Once those two CLs land we will be able to land this one.

[1] https://android-review.googlesource.com/c/platform/frameworks/av/+/837745
[2] https://android-review.googlesource.com/c/platform/bionic/+/818973

Bug: 118642754
Change-Id: I35409cbb6bfcd77e632567dd755376e345cfe67b
2019-01-31 14:37:34 -08:00
Ryan Prichard
ecdc451ccf Merge changes I3c9b1292,I05c28d6a,I788c4a95,If8cd798f,I1c8d1cd7, ...
* changes:
  Implement dynamic TLS accesses and allocation
  Implement TLS_DTPMOD and TLS_DTPREL relocations
  Ignore DT_TLSDESC_GOT / DT_TLSDESC_PLT
  Disable the dlfcn.dlopen_library_with_ELF_TLS test
  Add BionicAllocator::memalign
  Move the linker allocator into libc
  Replace some of linker_allocator's header includes
2019-01-28 19:32:59 +00:00
Florian Mayer
543b4013e7 Merge "Allow to reset malloc hooks." 2019-01-28 18:14:48 +00:00
Florian Mayer
db59b891ca Allow to reset malloc hooks.
This is used to prevent the additional indirection even after heap
profiling has finished, preventing any performance impact on processes
that are not currently being profiled.

Test: m
Test: flash sailfish
Test: try tearing down & re-enabling hooks

Bug: 120186127

Change-Id: Idc5988111a47870d2c093fd6a017b47e65f5616b
2019-01-28 15:01:50 +00:00
Ryan Prichard
16455b5100 Implement dynamic TLS accesses and allocation
Initialize a thread's DTV to an empty zeroed DTV. Allocate the DTV and
any ELF module's TLS segment on-demand in __tls_get_addr. Use a generation
counter, incremented in the linker, to signal when threads should
update/reallocate their DTV objects.

A generation count of 0 always indicates the constant zero DTV.

Once a DTV is allocated, it isn't freed until the thread exits, because
a signal handler could interrupt the fast path of __tls_get_addr between
accessing the DTV slot and reading a field of the DTV. Bionic keeps a
linked list of DTV objects so it can free them at thread-exit.

Dynamic TLS memory is allocated using a BionicAllocator instance in
libc_shared_globals. For async-signal safety, access to the
linker/libc-shared state is protected by first blocking signals, then by
acquiring the reader-writer lock, TlsModules::rwlock. A write lock is
needed to allocate or free memory.

In pthread_exit, unconditionally block signals before freeing dynamic
TLS memory or freeing the shadow call stack.

ndk_cruft.cpp: Avoid including pthread_internal.h inside an extern "C".
(The header now includes a C++ template that doesn't compile inside
extern "C".)

Bug: http://b/78026329
Bug: http://b/123094171
Test: bionic unit tests
Change-Id: I3c9b12921c9e68b33dcc1d1dd276bff364eff5d7
2019-01-25 17:53:01 -08:00
Ryan Prichard
96773a2daf Add BionicAllocator::memalign
Bionic needs this functionality to allocate a TLS segment with greater
than 16-byte alignment. For simplicity, this allocator only supports up
to one page of alignment.

The memory layout changes slightly when allocating an object of exactly
PAGE_SIZE alignment. Instead of allocating the page_info header at the
start of the page containing the pointer, it is allocated at the start
of the preceding page.

Bug: http://b/78026329
Test: linker-unit-tests{32,64}
Change-Id: I1c8d1cd7ca72d113bced5ee15ba8d831426b0081
2019-01-25 15:31:35 -08:00
Ryan Prichard
083d850b30 Move the linker allocator into libc
Rename LinkerMemoryAllocator -> BionicAllocator
Rename LinkerSmallObjectAllocator -> BionicSmallObjectAllocator

libc and the linker need to share an instance of the allocator for
allocating and freeing dynamic ELF TLS memory (DTVs and segments). The
linker also continues to use this allocator.

Bug: http://b/78026329
Test: /data/nativetest/bionic-unit-tests-static
Test: /data/nativetest64/bionic-unit-tests-static
Test: /data/nativetest/linker-unit-tests/linker-unit-tests32
Test: /data/nativetest64/linker-unit-tests/linker-unit-tests64
Change-Id: I2da037006ddf8041a75f3eba2071a8fcdcc223ce
2019-01-25 15:31:35 -08:00
Ryan Prichard
3ce06c7b0a Merge "Reassign TLS slot 2 to TLS_SLOT_APP." 2019-01-24 18:53:28 +00:00
Ryan Prichard
a0834d805c Reassign TLS slot 2 to TLS_SLOT_APP.
Bug: http://b/78026329
Bug: http://b/118381796
Test: mmma bionic
Change-Id: I1c50d3293206e59d54fbbfe9c9e3d6fd54dded3e
2019-01-23 18:48:48 -08:00
Ryan Savitski
f77928de32 android_mallopt: opcode preprocess define + missing header
Addressing Elliott's remaining comments on the android_mallopt change.
Intending to let this get merged in normally (should be clean).

Test: blueline-userdebug still builds.
Change-Id: I4f00191091b8af367f84d087432a5af5f83036ee
2019-01-23 18:40:17 +00:00
Ryan Savitski
ecc37e3877 conditional zygote child heap profiling + android_internal_mallopt
On user builds, heapprofd should only be allowed to profile apps that
are either debuggable, or profileable (according to the manifest). This
change exposes extra zygote-specific knowledge to bionic, and makes the
dedicated signal handler check for the special case of being in a zygote child.

With this & the corresponding framework change, we should now be
handling the 4 combinations of:
  {java, native} x {profile_at_runtime, profile_at_startup}.

See internal go/heapprofd-java-trigger for further context.

Test: on-device unit tests (shared & static) on blueline-userdebug.
Test: flashed blueline-userdebug, confirmed that java profiling activates from startup and at runtime.
Bug: 120409382
Change-Id: Ic251afeca4324dc650ac1d4f46976b526eae692a
(cherry picked from commit 998792e2b6)
Merged-In: Ic251afeca4324dc650ac1d4f46976b526eae692a
2019-01-23 18:30:54 +00:00
Ryan Prichard
fb8730d495 Handle R_GENERIC_TLS_TPREL relocations
This relocation is used for static TLS's initial-exec (IE) accesses.

A TLS symbol's value is its offset from the start of the ELF module's
TLS segment. It doesn't make sense to add the load_bias to this value,
so skip the call to soinfo::resolve_symbol_address.

Allow TLS relocations to refer to an unresolved weak symbol. In that case,
sym will be non-zero, but lsi will be nullptr. The dynamic linker resolves
the TPREL relocation to 0, making &missing_weak_symbol equal the thread
pointer.

Recognize Gold-style relocations to STB_LOCAL TLS symbols/sections and
issue an error.

Remove the "case R_AARCH64_TLS_TPREL64", because the R_GENERIC_TLS_TPREL
case handles it.

Remove the no-op R_AARCH64_TLSDESC handler. It's better to issue an error.
dlopen_library_with_ELF_TLS now fails with a consistent error about an
unimplemented dynamic TLS relocation.

Bug: http://b/78026329
Test: bionic unit tests (elftls tests are added in a later CL)
Change-Id: Ia08e1b5c8098117e12143d3b4ebb4dfaa5ca46ec
2019-01-17 00:45:55 -08:00
Ryan Prichard
1988350d1c Avoid a dlopen abort on an invalid TLS alignment
If the alignment of a TLS segment in a shared object is invalid, return
an error through dlerror() rather than aborting the process.

Bug: http://b/78026329
Test: bionic unit tests
Change-Id: I60e589ddd8ca897f485d55af089f08bd3ff5b1fa
2019-01-16 23:19:40 -08:00
Ryan Prichard
361c1b4a3b Initialize static TLS memory using module list
This implementation simply iterates over each static TLS module and
copies its initialization image into a new thread's static TLS block.

Bug: http://b/78026329
Test: bionic unit tests
Change-Id: Ib7edb665271a07010bc68e306feb5df422f2f9e6
2019-01-16 16:52:47 -08:00
Ryan Prichard
e5e69e0912 Record TLS modules and layout static TLS memory
Bug: http://b/78026329
Test: bionic unit tests
Change-Id: Ibf1bf5ec864c7830e4cd1cb882842b644e6182ae
2019-01-16 16:52:47 -08:00
Ryan Prichard
977e47d018 StaticTlsLayout: add exe/tcb and solib layout
Replace reserve_tcb with reserve_exe_segment_and_tcb, which lays out both
the TCB and the executable's TLS segment, accounting for the difference in
layout between variant 1 and variant 2 targets.

The function isn't actually called with a non-null TlsSegment* yet.

Bug: http://b/78026329
Test: bionic unit tests
Change-Id: Ibd6238577423a7d0451f36da7e64912046959796
2019-01-16 15:54:52 -08:00
Ryan Prichard
4809755c0f Add a __bionic_get_tls_segment function
The function searches for a TLS segment in a ElfXX_Phdr table.

Bug: http://b/78026329
Test: bionic unit tests
Change-Id: I221b13420d1a2da33fc2174b7dd256589f6ecfdb
2019-01-16 01:11:26 -08:00
Ryan Prichard
c86576c1fb Factor out ScopedRWLock into its own header
Bug: http://b/78026329
Test: bionic unit tests
Change-Id: I1d1276da835bc8ecac7a7abb714d639a1ee58007
2019-01-16 01:11:26 -08:00
Ryan Prichard
2e724175ac Remove TLS_SLOT_TSAN(8)
As of the switch to clang-r346389c, it has been replaced with
TLS_SLOT_SANITIZER(6). lld reserves 8 words beyond the TP on arm/arm64, so
Bionic can't use anything beyond 7.

The DTV and bionic_tls slots on x86 haven't been part of a release yet,
and they should be strictly internal to Bionic anyway, so shift them down.

Bug: http://b/78026329
Test: bionic unit tests
Change-Id: Ifb3b2d8d85efe1417ee9a10b657b665ec6f2fd3d
2019-01-16 01:11:26 -08:00
Ryan Prichard
45d1349c63 Reorganize static TLS memory for ELF TLS
For ELF TLS "local-exec" accesses, the static linker assumes that an
executable's TLS segment is located at a statically-known offset from the
thread pointer (i.e. "variant 1" for ARM and "variant 2" for x86).
Because these layouts are incompatible, Bionic generally needs to allocate
its TLS slots differently between different architectures.

To allow per-architecture TLS slots:
 - Replace the TLS_SLOT_xxx enumerators with macros. New ARM slots are
   generally negative, while new x86 slots are generally positive.
 - Define a bionic_tcb struct that provides two things:
    - a void* raw_slots_storage[BIONIC_TLS_SLOTS] field
    - an inline accessor function: void*& tls_slot(size_t tpindex);

For ELF TLS, it's necessary to allocate a temporary TCB (i.e. TLS slots),
because the runtime linker doesn't know how large the static TLS area is
until after it has loaded all of the initial solibs.

To accommodate Golang, it's necessary to allocate the pthread keys at a
fixed, small, positive offset from the thread pointer.

This CL moves the pthread keys into bionic_tls, then allocates a single
mapping per thread that looks like so:
 - stack guard
 - stack [omitted for main thread and with pthread_attr_setstack]
 - static TLS:
    - bionic_tcb [exec TLS will either precede or succeed the TCB]
    - bionic_tls [prefixed by the pthread keys]
    - [solib TLS segments will be placed here]
 - guard page

As before, if the new mapping includes a stack, the pthread_internal_t
is allocated on it.

At startup, Bionic allocates a temporary bionic_tcb object on the stack,
then allocates a temporary bionic_tls object using mmap. This mmap is
delayed because the linker can't currently call async_safe_fatal() before
relocating itself.

Later, Bionic allocates a stack-less thread mapping for the main thread,
and copies slots from the temporary TCB to the new TCB.
(See *::copy_from_bootstrap methods.)

Bug: http://b/78026329
Test: bionic unit tests
Test: verify that a Golang app still works
Test: verify that a Golang app crashes if bionic_{tls,tcb} are swapped
Merged-In: I6543063752f4ec8ef6dc9c7f2a06ce2a18fc5af3
Change-Id: I6543063752f4ec8ef6dc9c7f2a06ce2a18fc5af3
(cherry picked from commit 1e660b70da)
2019-01-11 15:34:22 -08:00
Ryan Prichard
0b0ee0c634 libc_shared_globals: add a constexpr ctor
Having a constexpr constructor should guarantee that the static
`globals` variable in __libc_shared_globals is initialized statically
(as opposed to dynamically), which is important because
__libc_shared_globals is called very early (before the linker has
relocated itself). With the constructor, though, the fields can safely
have in-line default initializers.

Bug: none
Test: bionic unit tests
Change-Id: Icde821557369625734a4d85d7ff55428bad5c247
2019-01-03 17:11:27 -08:00
Chih-Hung Hsieh
770032ddfa Fix/suppress bionic google-explicit-constructor warnings
* Add explicit to conversion constructors/operators

Bug: 28341362
Test: make with WITH_TIDY=1 DEFAULT_GLOBAL_TIDY_CHECKS=-*,google-explicit-constructor
Change-Id: Id1ad0327c1b8c6f094bcbb3ae599bc1f716b3f2f
2019-01-02 11:04:05 -08:00
Ryan Prichard
4825c6d814 Reserve TLS_SLOT_SANITIZER with value 6.
This slot will replace TLS_SLOT_TSAN, which needs to be removed for ELF
TLS compatibility. The platform has both slots reserved until compiler-rt
can be updated. See:
 - https://reviews.llvm.org/D53906
 - discussion on AOSP change Idf25d2ee457a5d26d0bdd6281cee72c345c8b755

Bug: http://b/78026329
Test: m
Change-Id: Ifd5aeb5711dc88266e7350cb022146dd87cfd7be
2018-12-11 13:02:56 -08:00
Ryan Prichard
37754cdef6 Move errno to a pthread_internal_t field.
This change is intended to allow native-bridge to use independent
TLS memory for host and guest environments, while still sharing a
thread-local errno between the two.

Bug: http://b/78026329
Test: bionic unit tests
Change-Id: I838cd321e159add60760bc12a8aa7e9ddc960c33
Merged-In: I838cd321e159add60760bc12a8aa7e9ddc960c33
(cherry picked from commit a9c7c55462)
2018-12-11 12:59:23 -08:00
Elliott Hughes
34583c1089 Move dlerror out of a TLS slot and into a pthread_internal_t member.
Bug: N/A
Test: boots, tests pass.
Change-Id: Idf25d2ee457a5d26d0bdd6281cee72c345c8b755
2018-12-06 05:19:57 +00:00
Ryan Prichard
07440a8773 Replace TLS_SLOT_BIONIC_PREINIT w/ shared globals
Instead of passing the address of a KernelArgumentBlock to libc.so for
initialization, use __loader_shared_globals() to initialize globals.

Most of the work happened in the previous CLs. This CL switches a few
KernelArgumentBlock::getauxval calls to [__bionic_]getauxval and stops
routing the KernelArgumentBlock address through the libc init functions.

Bug: none
Test: bionic unit tests
Change-Id: I96c7b02c21d55c454558b7a5a9243c682782f2dd
Merged-In: I96c7b02c21d55c454558b7a5a9243c682782f2dd
(cherry picked from commit 746ad15912)
2018-12-04 13:51:56 -08:00
Ryan Prichard
5a66490e3b Use shared globals so getauxval works earlier
Make getauxval() work in .preinit_array. It still won't be usable for
ifuncs unless we can guarantee that the __loader_shared_globals relocation
is resolved before the ifunc calls [__bionic_]getauxval.

Define __bionic_getauxval for use in replacing calls to
KernelArgumentBlock::getauxval, which doesn't (and sometimes isn't allowed
to) access TLS variables like errno.

Bug: http://b/25751302
Test: bionic unit tests
Change-Id: I461feeaed7f43cfa2a2b6c34147194f0df82b516
Merged-In: I461feeaed7f43cfa2a2b6c34147194f0df82b516
(cherry picked from commit bdab4a2b97)
2018-12-04 13:51:46 -08:00
Ryan Prichard
9cfca866ce Split main thread init into early+late functions
Split __libc_init_main_thread into __libc_init_main_thread_early and
__libc_init_main_thread_late. The early function is called very early in
the startup of the dynamic linker and static executables. It initializes
the global auxv pointer and enough TLS memory to do system calls, access
errno, and run -fstack-protector code (but with a zero cookie because the
code for generating a cookie is complex).

After the linker is relocated, __libc_init_main_thread_late finishes
thread initialization.

Bug: none
Test: bionic unit tests
Change-Id: I6fcd8d7587a380f8bd649c817b40a3a6cc1d2ee0
Merged-In: I6fcd8d7587a380f8bd649c817b40a3a6cc1d2ee0
(cherry picked from commit 39bc44bb0e)
2018-12-04 13:51:36 -08:00
Ryan Prichard
48b1159bb8 Use shared globals to init __progname + environ
Initialize the __progname and environ global variables using
libc_shared_globals rather than KernelArgumentBlock.

Also: suppose the linker is invoked on an executable:

    linker prog [args...]

The first argument passed to main() and constructor functions is "prog"
rather than "linker". For consistency, this CL changes the BSD
__progname global from "linker" to "prog".

Bug: none
Test: bionic unit tests
Change-Id: I376d76953c9436706dbc53911ef6585c1acc1c31
2018-11-28 14:26:14 -08:00
Ryan Prichard
7752bcb234 Move the abort message to libc_shared_globals
__libc_shared_globals() is available in dynamic modules as soon as
relocation has finished (i.e. after ifuncs run). Before ifuncs have run,
the android_set_abort_message() function already doesn't work because it
calls public APIs via the PLT. (If this matters, we can use a static
bool variable to enable android_set_abort_message after libc
initialization).

__libc_shared_globals() is hidden, so it's available in the linker
immediately (i.e. before relocation). TLS memory (e.g. errno) currently
isn't accessible until after relocation, but a later patch fixes that.

Bug: none
Test: bionic unit tests
Change-Id: Ied4433758ed2da9ee404c6158e319cf502d05a53
2018-11-28 14:26:14 -08:00
Ryan Prichard
abf736a780 Expose libc_shared_globals to libc.so with symbol
Previously, the address of the global variable was communicated from the
dynamic linker to libc.so using a field of KernelArgumentBlock, which is
communicated using the TLS_SLOT_BIONIC_PREINIT slot.

As long as this function isn't called during relocations (i.e. while
executing an ifunc), it always return a non-NULL value. If it's called
before its PLT entry is relocated, I expect a crash.

I removed the __libc_init_shared_globals function. It's currently empty,
and I don't think there's one point in libc's initialization where
shared globals should be initialized.

Bug: http://b/25751302
Test: bionic unit tests
Change-Id: I614d25e7ef5e0d2ccc40d5c821dee10f1ec61c2e
2018-11-28 14:26:14 -08:00
Luke Huang
f47e89f29b Merge "Replace android_open_proxy with dns_open_proxy" 2018-11-28 12:21:33 +00:00
Peter Collingbourne
8d849ffbad Merge "Allocate a small guard region around the shadow call stack." 2018-11-19 20:44:03 +00:00
Luke Huang
e3ed892faa Replace android_open_proxy with dns_open_proxy
remove android_open_proxy and use dns_open_proxy instead of it.
dns_open_proxy is in libnetd_client and
it does the same thing as android_open_proxy except return value.
It returns fd directly now.

Test: build, dns works fine
Change-Id: I984743fb50b23eeb9a7d24e9fc347832acfe2afe
2018-11-19 18:00:37 +08:00
Peter Collingbourne
734beec3d4 Allocate a small guard region around the shadow call stack.
This lets us do two things:

1) Make setjmp and longjmp compatible with shadow call stack.
   To avoid leaking the shadow call stack address into memory, only the
   lower log2(SCS_SIZE) bits of x18 are stored to jmp_buf. This requires
   allocating an additional guard page so that we're guaranteed to be
   able to allocate a sufficiently aligned SCS.

2) SCS overflow detection. Overflows now result in a SIGSEGV instead
   of corrupting the allocation that comes after it.

Change-Id: I04d6634f96162bf625684672a87fba8b402b7fd1
Test: bionic-unit-tests
2018-11-16 14:37:08 -08:00
Elliott Hughes
c0f4656452 Make android_get_application_target_sdk_version available to the NDK.
Also move this and android_get_device_api_level into <android/api-level.h>
so that they're always available.

This involves cleaning up <sys/cdefs.h> slightly.

Bug: N/A
Test: builds
Change-Id: I25435c55f3549cd0d827a7581bee75ea8228028b
2018-11-15 11:07:30 -08:00
Elliott Hughes
ff1428a48e Move API levels from uint32_t to int.
(cherrypick of a6c71a09670ca636cca5cfea9d74b03a951e2b5e.)

Bug: N/A
Test: builds
Change-Id: I9c414e30e3c4fe2a4e16a2fe4ce18eae85fe4844
2018-11-13 21:25:07 -08:00
Elliott Hughes
5e62b34c0d Clean up bionic_macros.h a bit.
Use <android-base/macros.h> instead where possible, and move the bionic
macros out of the way of the libbase ones. Yes, there are folks who manage
to end up with both included at once (thanks OpenGL!), and cleaning that
up doesn't seem nearly as practical as just making this change.

Bug: N/A
Test: builds
Change-Id: I23fc544f39d5addf81dc61471771a5438778895b
2018-10-25 11:00:00 -07:00
Florian Mayer
f7f71e3c7b Add RT signal to load heapprofd library.
Tests: Ran malloc_debug_unit_tests
Tests: Flashed to walleye, sent signal, observed
  "Unable to open shared library: heapprofd.so".

Change-Id: Ia8ce216837e29e3edbda8789ca28023d53fa1fda
2018-10-18 21:38:06 +01:00
Elliott Hughes
92a9116100 strerror: add missing ERFKILL and EHWPOISON.
There's little value to having strings for these, but we may as well
for consistency. There's no ELASTERRNO constant we can use to check
whether we've fallen behind again, but these were added in 2009 and
2011 respectively, so we're not likely to have to deal with any more
new errno values any time soon...

Bug: http://b/117755069
Test: ran tests
Change-Id: I5b7155c22cad92c2fe03a0b4c7cae415c37fa186
2018-10-15 13:12:19 -07:00
Treehugger Robot
391af2cefe Merge "Allow invoking the linker on an executable." 2018-10-11 01:04:57 +00:00
Ryan Prichard
8f639a4096 Allow invoking the linker on an executable.
The executable can be inside a zip file using the same syntax used for
shared objects: path.zip!/libentry.so.

The linker currently requires an absolute path. This restriction could be
loosened, but it didn't seem important? If it allowed non-absolute paths,
we'd need to decide how to handle:
 - foo/bar      (relative to CWD?)
 - foo          (search PATH / LD_LIBRARY_PATH, or also relative to CWD?)
 - foo.zip!/bar (normalize_path() requires an absolute path)

The linker adjusts the argc/argv passed to main() and to constructor
functions to hide the initial linker argument, but doesn't adjust the auxv
vector or files like /proc/self/{exe,cmdline,auxv,stat}. Those files will
report that the kernel loaded the linker as an executable.

I think the linker_logger.cpp change guarding against (g_argv == NULL)
isn't actually necessary, but it seemed like a good idea given that I'm
delaying initialization of g_argv until after C++ constructors have run.

Bug: http://b/112050209
Test: bionic unit tests
Change-Id: I846faf98b16fd34218946f6167e8b451897debe5
2018-10-10 14:31:06 -07:00
Josh Gao
baf20fc912 Block TIMER_SIGNAL in sigprocmask(SIG_SETMASK, ...).
Previously, we were zeroing out the reserved signals, when we actually
wanted to have TIMER_SIGNAL always be blocked, and the other signals
always be unblocked. This resulted in process termination when a
SIGEV_THREAD timer callback calls sigprocmask(SIG_SETMASK, ...) with
any signal mask value, and then subsequently fails to complete its
callback and reach the sigtimedwait in bionic before the next timer
iteration triggers.

Add a how argument to filter_reserved_signals to appropriately
block/unblock our reserved signals.

Bug: http://b/116783733
Test: bionic-unit-tests32/64
Change-Id: Ie5339682cdeb914711cd4089cd26ee395704d0df
2018-10-09 16:27:22 -07:00
Josh Gao
f5693c688d Generalize abort's inline_tgkill, use it in fdsan.
Convert abort's inline_tgkill to do the equivalent of
pthread_sigqueue(pthread_self(), ...), so that we can use it in fdsan
as well.

Test: bionic-unit-tests
Test: debuggerd_test32
Test: debuggerd_test64
Change-Id: I92a7b84e2f00ce021b4043ed8a3bd8683d77fe9c
2018-08-31 16:39:23 -07:00
Elliott Hughes
99d54656bd Add PR_SET_VMA and PR_SET_VMA_ANON_NAME to <sys/prctl.h>.
We've copied & pasted these to too many places. And if we're going to
have another go at upstreaming these, that's probably yet another reason
to have the *values* in just one place. (Even if upstream wants different
names, we'll likely keep the legacy names around for a while for source
compatibility.)

Bug: http://b/111903542
Test: ran tests
Change-Id: I8ccc557453d69530e5b74f865cbe0b458c84e3ba
2018-08-22 10:36:23 -07:00
George Burgess IV
fa5410fdb7 libc: enable -Wimplicit-fallthrough
libc had some -Wimplicit-fallthrough warnings. They all seem to be
benign. We're trying to enable this flag globally, so we need to
annotate these breaks here.

Bug: 112564944
Test: Builds
Change-Id: I5afae694cc4cf26ad1a61e2c8ae91f00cda7c733
2018-08-15 10:11:08 -07:00
Josh Gao
e6dab7b55f fdsan: minor refactoring.
Make it easier for other code to parse the fdsan table themselves by
making it so that they can include the bionic_fdsan.h header to get a
struct definition with the layout without bringing in other
dependencies.

Test: treehugger
Change-Id: I3583ef113991234aa83cd193a4eb139ad06737c7
2018-08-06 18:47:29 -07:00
Yi Kong
32bc0fcf69 Modernize codebase by replacing NULL with nullptr
Fixes -Wzero-as-null-pointer-constant warning.

Test: m
Bug: 68236239
Change-Id: I5b4123bc6709641315120a191e36cc57541349b2
2018-08-02 18:09:44 -07:00
Josh Gao
f6e5b58260 Introduce api to track fd ownership in libc.
Add two functions to allow objects that own a file descriptor to
enforce that only they can close their file descriptor.

Use them in FILE* and DIR*.

Bug: http://b/110100358
Test: bionic_unit_tests
Test: aosp/master boots without errors
Test: treehugger
Change-Id: Iecd6e8b26c62217271e0822dc3d2d7888b091a45
2018-07-19 14:28:54 -07:00
Elliott Hughes
468efc80da Reimplement popen(3)/pclose(3).
pclose(3) is now an alias for fclose(3). We could add a FORTIFY check
that you use pclose(3) if and only if you used popen(3), but there seems
little value to that when we can just do the right thing.

This patch also adds the missing locking to _fwalk --- we need to lock
both the global list of FILE*s and also each FILE* we touch. POSIX says
that "The popen() function shall ensure that any streams from previous
popen() calls that remain open in the parent process are closed in the
new child process", which we implement via _fwalk(fclose) in the child,
but we might want to just make *all* popen(3) file descriptors O_CLOEXEC
in all cases.

Ignore fewer errors in popen(3) failure cases.

Improve popen(3) test coverage.

Bug: http://b/72470344
Test: ran tests
Change-Id: Ic937594bf28ec88b375f7e5825b9c05f500af438
2018-07-11 12:15:26 -07:00
Adhemerval Zanella
37d4e67bb0 Set __bionic_asm_align to 16 for arm64
As for others targets, it is better to align function text by minimim
cacheline size.  This patch changes arm __bionic_asm_align to 16.

Test: bionic tests on aarch64.
Change-Id: Ib121663c65493d33d6803e2c5139d247a8cae858
2018-06-26 15:58:52 -03:00
Elliott Hughes
95bca3f7d4 Remove valgrind workarounds.
Bug: http://b/77856586
Test: ran 32-bit x86 tests on host
Change-Id: I98f6262bb1363ed5c8dd533b1f89b59b2b188525
2018-06-12 15:29:36 -07:00
Ryan Prichard
27475b5105 Initialize __libc_sysinfo early on.
__libc_sysinfo is hidden, so accessing it doesn't require a relocated GOT.
It is important not to have a relocatable initializer on __libc_sysinfo,
because if it did have one, and if we initialized it before relocating the
linker, then on 32-bit x86 (which uses REL rather than RELA), the
relocation step would calculate the wrong addend and overwrite
__libc_sysinfo with garbage.

Asides:

 * It'd be simpler to keep the __libc_sysinfo initializer for static
   executables, but the loader pulls in libc_init_static (even though it
   uses almost none of the code in that file, like __libc_init).

 * The loader has called __libc_init_sysinfo three times by the time it
   has relocated itself. A static executable calls it twice, while libc.so
   calls it only once.

Bug: none
Test: lunch aosp_x86-userdebug ; emulator
Test: adb shell /data/nativetest/bionic-unit-tests/bionic-unit-tests
Test: adb shell /data/nativetest/bionic-unit-tests-static/bionic-unit-tests-static
Change-Id: I5944f57847db7191608f4f83dde22b49e279e6cb
2018-05-30 16:44:23 -07:00
Tom Cherry
c2b9fec50b Require vendor users and groups to start with vendor_
Require that users and groups found in /vendor/etc/{passwd,group}
start with vendor_.  This is needed to compliance with Treble as
without this prefix, it is possible for a new system image to create a
user/group name that a vendor has already used, causing a collision.

Bug: 79528966
Test: new unit test
Change-Id: I07500641e165f41526a8101592d83fa174e7a711
2018-05-15 14:10:21 -07:00
Narayan Kamath
38e960b7aa bionic_fortify: clarify error message for an out of bounds FD.
It seems clearer to include FD_SETSIZE in the message. set_size
is sizeof(fd_set) so there's an extra mental hoop to jump if that's
in the error message.

Test: make
Change-Id: I5cdb62465b658ac0eaeccbfb826d135820cf613a
2018-03-14 12:37:25 +00:00
Elliott Hughes
71ba5899ae Rewrite system(3) to use posix_spawn(3).
We saw crashes from pthread_exit+debuggerd on LP32
(https://issuetracker.google.com/72291624), and it seems like the
equivalent problem should exist with system(3). I fixed posix_spawn(3)
as part of that bug, so the easiest fix is probably to reuse that.

Bug: http://b/72470344
Test: ran tests
Change-Id: I05f838706f2b4a14ac3ee21292833e6c8579b0d4
2018-03-05 17:20:12 -08:00