This replaces a single 2Gb readable memory region with a bunch of tiny
regions, and leaves the bulk of 2Gb mapped but unaccessible. This makes
it harder to defeat ASLR by probing for the CFI shadow region.
Sample CFI shadow mapping with this change:
7165151000-716541f000 ---p 00000000 00:00 0 [anon:cfi shadow]
716541f000-7165420000 r--p 00000000 00:00 0 [anon:cfi shadow]
7165420000-71654db000 ---p 00000000 00:00 0 [anon:cfi shadow]
71654db000-71654dc000 r--p 00000000 00:00 0 [anon:cfi shadow]
71654dc000-71654dd000 r--p 00000000 00:00 0 [anon:cfi shadow]
71654dd000-71654f0000 ---p 00000000 00:00 0 [anon:cfi shadow]
71654f0000-71654f1000 r--p 00000000 00:00 0 [anon:cfi shadow]
71654f1000-71e5151000 ---p 00000000 00:00 0 [anon:cfi shadow]
This change degrades CFI diagnostics for wild jumps and casts (i.e. when
the target of a CFI check is outside of any known library bounds). This
is acceptable, because CFI does not have much to tell about those cases
anyway. Such bugs will show up as SEGV_ACCERR crashes inside
__cfi_slowpath in libdl.so from now on.
Bug: 158113540
Test: bionic-unit-tests/cfi_test.*
Test: adb shell cat /proc/$PID/maps | grep cfi
Change-Id: I57cbd0d3f87eb1610ad99b48d98ffd497ba214b4
Merged-In: I57cbd0d3f87eb1610ad99b48d98ffd497ba214b4
XOM is no longer supported by the build system, so remove these
properties.
Bug: 123034666
Bug: 147300048
Test: Build succeeds.
Change-Id: I77efc98241f45b1a78b1cca5560f64eef5ef22f4
The mips/mips64 targets were never able to pass these tests, and the
supported architectures don't need any of these workarounds.
Test: treehugger
Change-Id: I640a8b7a98ae13d9d9cdb09b0fbef61d31d4c79a
When a library is present in a namespace via the secondary_namespaces
list (i.e. the executable, LD_PRELOAD, DF_1_GLOBAL, or
android_create_namespace inheritance), then we want to search that
library's symbols, but not the symbols of its dependencies. Otherwise,
we want to search the dependencies to handle cross-NS dependency.
Bug: http://b/148569846
Test: bionic unit tests
Change-Id: If798d69de28ed5c0f1a155e4ff85c7e08934e531
Test (a) that we can load the library, but also (b) that readelf thinks
it contains the relocation encoding we were expecting. Do this for all
four of RELR, ANDROID_RELR, relocation packer, and the original ELF
relocation encoding.
Bug: http://b/147452927
Test: treehugger
Change-Id: I5fab72f99d46991c1b206a1c15c76e185b7148b3
Until now we've only supported RELR with our own OS-private-use
constants. Add support for the official numbers (while maintaining
support for the historical numbers).
Add tests to ensure we continue to support both indefinitely.
We can't yet flip the build system over to using the official constants
because the old GNU binutils objcopy we still use in most cases (for the
mini-debug section) only supports the historical constants.
Bug: http://b/147452927
Test: treehugger
Change-Id: If214fce7fade4316115947e90b78ab40864b61f2
Bug: 122332847
Bug: 130734182
Test: mmm bionic/tests; same files installed before & after
Test: m cts; same files in cts before & after
Test: `objdump -x <files> | grep NEEDED` is identical
Test: `objdump -x <files> | grep RUNPATH` difference make sense
(additional lib64 entries from soong, minimal reorder)
Test: treehugger
Change-Id: I6eea4c3f9c0040efeba64e2b47c7b573767cd386
The test starts failing in the upcoming lld update. The root cause is
that no relro section is specified by the linker script, and the orphan
placement algorithm decides to place them after .text which is a
misaligned place.
Test: bionic-unit-tests
Bug: 139089152
Bug: 131328001
Change-Id: I2140d8a9fd7c712f1d31a541a3b4a10788385e98
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
Cleanup of references to 'coverage' in build files. Part of a larger
cleanup to make fuzzing work again in the Android build tree.
Also fixed a test issue with emulated TLS with the new changes, and
removed libc.so fuzzer support until a linked bug is fixed
(b/132640749).
Bug: 121042685
Test: With all patches in the bug merged: mmma bionic
Change-Id: I592352fe9210ff811a2660a88cbbfe48d70a1e57
Merged-In: I592352fe9210ff811a2660a88cbbfe48d70a1e57
It's possible and sometimes beneficial for a library to have disjoint mappings
and for other libraries to be mapped into the gap between the mappings using
ANDROID_DLEXT_RESERVED_ADDRESS. See for example the proposal for partitioning
in lld [1].
Because the find_containing_library and do_dl_unwind_find_exidx functions use
a simple bounds check to figure out whether a pointer belongs to a library
they will, given a pointer into a library mapped into the gap of a library
with disjoint mappings, return a pointer to the soinfo for the outer library
instead of the inner one, because the outer library will appear before the
inner one in the solist.
From a user perspective this means that we won't be able to unwind the inner
library's frames on 32-bit ARM with libgcc, dladdr() will return information
for the outer library given a pointer to the inner one and dlopen() et al will
use the linker namespace of the outer library when called from the inner one
(although they will usually be the same).
To make this work correctly, make it so that once find_containing_library
sees a match for the bounds check, it examines the library's PT_LOADs to
make sure that there is a mapping for the given address. This is similar
to how libgcc and libunwind_llvm already handle finding the PT_GNU_EH_FRAME
on non-ARM32 platforms [2,3]. do_dl_unwind_find_exidx is reimplemented in
terms of find_containing_library.
[1] http://lists.llvm.org/pipermail/llvm-dev/2019-February/130583.html
[2] e739ac0e25/libunwind/src/AddressSpace.hpp (L523)
[3] https://android.googlesource.com/toolchain/gcc/+/master/gcc-4.9/libgcc/unwind-dw2-fde-dip.c#294
Test: /data/nativetest{,64}/bionic-unit-tests/bionic-unit-tests on walleye-userdebug
Change-Id: I368fe6ad3c470b3dff80f7d9b04253566d63a7d2
Introduce a new flag ANDROID_DLEXT_RESERVED_ADDRESS_RECURSIVE which
instructs the linker to use the reserved address space to load all of
the newly-loaded libraries required by a dlopen() call instead of only
the main library. They will be loaded consecutively into that region if
they fit. The RELRO sections of all the loaded libraries will also be
considered for reading/writing shared RELRO data.
This will allow the WebView implementation to potentially consist of
more than one .so file while still benefiting from the RELRO sharing
optimisation, which would otherwise only apply to the "root" .so file.
Test: bionic-unit-tests (existing and newly added)
Bug: 110790153
Change-Id: I61da775c29fd5017d9a1e2b6b3757c3d20a355b3
LIB is now expanded to either lib or lib64. Add a new lib
libtest_dt_runpath_y which is under lib or lib64 directory to the tests.
Test: run bionic-unit-tests
Merged-In: Ib051d8cae4d50b452759d594c87126b45bc9e959
Change-Id: Ib051d8cae4d50b452759d594c87126b45bc9e959
The dlext.ns_anonymous test copies the loaded segments of this shared
object into a new mapping, so every segment must be readable. Turn off
eXecute-Only-Memory.
Bug: http://b/123034666
Test: bionic-unit-tests --gtest_filter=dlext.ns_anonymous
Change-Id: I2d427feb81d353e0403c7ef251a55afb4d8729b4
* Add explicit to conversion constructors/operators
Bug: 28341362
Test: make with WITH_TIDY=1 DEFAULT_GLOBAL_TIDY_CHECKS=-*,google-explicit-constructor
Change-Id: Id1ad0327c1b8c6f094bcbb3ae599bc1f716b3f2f
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
* HWASan report invalid use of the allocator api (like alignment not
being power of two, or allocation size too large) in a way tests do not
expect.
* Code in .preinit_array runs before HWASan shadow is initialized and
needs to be excluded from instrumentation.
* It looks that mm system calls (mmap/mprotect/etc) will not allow
tagged pointers. In fact, the use of mprotect on malloc()ed memory is
doubtful - one can imagine some kind of speculative load from such
memory, as compiler knows that it is addressable.
Bug: 114279110
Test: bionic-unit-tests with hwasan
Change-Id: I6ba4b46a0d554de77c923ad134cf156ce4ddba1b
This reverts commit 8e462d411a.
Reason for revert: this lld bug has been fixed upstream and in AOSP prebuilts
Bug: 80109858
Change-Id: Ied600324201e1a014a1d4e6742767e2ddd94999a
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
The tls_nodelete state should apply to load_group not
isolated soinfo. This actually also means that multiple
soinfos may have tls_counter on their dso_handles.
This change replaces TLS_NODELETE flag with secondary counter.
Note that access to the secondary counter (located inside soinfo)
is pretty expensive because it requires soinfo lookup by dso_handle
whereas dso_handle counter is much faster. This is why it is updated
only when dso_handle counter starts or hits 0.
Bug: http://b/80278285
Test: bionic-unit-tests --gtest_filter=dl*
Change-Id: I535583f6714e45fa2a7eaf7bb3126da20ee7cba9
vdso should be available in all namespaces when present. This
bug went undetected because the way libc currently uses vdso (it
does all the lookups itself). This makes it available for the
programs that want to take advantage by dlopening it.
Bug: http://b/73105445
Bug: http://b/79561555
Test: adb shell /data/nativetest/arm/bionic-unit-tests/bionic-unit-tests --gtest_filter=dl.exec_with_ld_config_file
Test: adb shell /data/nativetest/bionic-unit-tests/bionic-unit-tests --gtest_filter=dl*
Change-Id: I8eae0c9848f256190d1c9ec85d10dc6ce383a8bc
(cherry picked from commit 69c68c46ac)
* Since Android does not have __tls_get_addr yet,
-fno-emulated-tls is only a test of compiler.
Lld is correct to reject this at link time.
But if the purpose of this test is to check at run-time,
allow_undefined-symbols is the trick to get the linked library.
Bug: http://b/74361956
Test: build and compare linked file
Change-Id: Ibcdc8b50aeeaec9d7d308b66df2a6997ce3c1a4f
Other build rules create and use a test config file in the intermediate
directory containing $(LOCAL_BUILT_MODULE). Currently, this makefile
deletes $(dir $(LOCAL_BUILT_MODULE)) (aka $(dir $@)), so it can delete
the config file after it's created and before it's used. Avoid this
issue by using $(dir $@)/zipdir as the working directory for
constructing a zip file.
Bug: b/74524170
Test: mmma bionic
Test: run Bionic unit tests
Change-Id: Icee4d7bc72ba1c136385a0cb2c28491649598e7c
This commit allows users to create a link without soname filters between
two linker namespaces.
The motivation is to establish one-way shared library isolation. For
example, assume that there are two linker namespaces `default` and
`vndk`. We would like to limit the shared libraries that can be used by
the `default` namespace. In the meanwhile, we would like to allow the
`vndk` namespace to use shared libs from the `default` namespace if the
soname cannot be find in the search path or loaded sonames of the `vndk`
namespace.
shared_libs = %VNDK_CORE_LIBRARIES%
shared_libs += %VNDK_SAMEPROCESS_LIBRARIES%
vndk <-------------------------------------------- default
\_______________________________________________/^
allow_all_shared_libs = true
android_link_namespaces_all_libs() is added to libdl, but it is
versioned as LIBC_PRIVATE. android_link_namespaces_all_libs() is only
for unit tests.
Bug: 69824336
Test: adb shell /data/nativetest/linker-unit-tests/linker-unit-tests32
Test: adb shell /data/nativetest64/linker-unit-tests/linker-unit-tests64
Test: adb shell /data/nativetest/bionic-unit-tests/bionic-unit-tests
Test: adb shell /data/nativetest64/bionic-unit-tests/bionic-unit-tests
Test: Update /system/etc/ld.config*.txt and check whether the vndk
linker namespace of the vendor process can access the shared libs from
the default linker namespace.
Change-Id: I2879f0c5f5af60c7e56f8f743ebd2872e552286b
Introduce new flag to mark soinfo as TLS_NODELETE when
there are thread_local dtors associated with dso_handle
belonging to it.
Test: bionic-unit-tests --gtest_filter=dl*
Test: bionic-unit-tests-glibc --gtest_filter=dl*
Bug: https://github.com/android-ndk/ndk/issues/360
Change-Id: I724ef89fc899788f95c47e6372c38b3313f18fed
This change addresses multiple problems introduced by
02586a2a34
1. In the case of unsuccessful dlopen the failure guard is triggered
for two namespaces which leads to double unload.
2. In the case where load_tasks includes libraries from 3 and more
namespaces it results in incorrect linking of libraries shared between
second and third/forth and so on namespaces.
The root cause of these problems was recursive call to find_libraries.
It does not do what it is expected to do. It does not form new load_tasks
list and immediately jumps to linking local_group. Not only this skips
reference counting it also will include unlinked but accessible library
from third (and fourth and fifth) namespaces in invalid local group. The
best case scenario here is that for 3 or more namesapces this will
fail to link. The worse case scenario it will link the library
incorrectly with will lead to very hard to catch bugs.
This change removes recursive call and replaces it with explicit list of
local_groups which should be linked. It also revisits the way we do
reference counting - with this change the reference counts are updated after
after libraries are successfully loaded.
Also update soinfo_free to abort in case when linker tries to free same
soinfo for the second time - this makes linker behavior less undefined.
Test: bionic-unit-tests
Bug: http://b/69787209
Change-Id: Iea25ced181a98c6503cce6e2b832c91d697342d5
This reverts commit 58554ccb8a.
causes /vendor/bin/qseecomd to hit the new abort:
[ 8.983301] c5 603 DEBUG: Abort message: 'soinfo=0x7147894cd0 is not in soinfo_list (double unload?)'
Bug: http://b/69909887
Bug: http://b/69787209
Change-Id: Ied38f797e0a071a1acc5ed41adf1b45e855143c7
In the case of unsuccessful dlopen the failure guard is triggered
for two namespaces which leads to double unload.
Also update soinfo_free to abort in case when linker tries to free same
soinfo for the second time - this makes linker behavior less undefined.
Test: bionic-unit-tests
Bug: http://b/69787209
Change-Id: I886787ee021b050667f967bce7aa2708390886ea
there's no use case for prepending/appending to bool, and string
properties within module struct. Declearing "*bool" and "*string" almost
cover everything user need.
Test: m -j checkbuild
Bug: b/68853585
Change-Id: I8342d4a43fb81f2842532ddb38fba414767ac82a
Using fclose to get the same address for the test assertion because
Samsung already uses LD_PRELOAD to intercept `close`.
Bug: http://b/67978141
Bug: http://b/68855476
Test: ran tests
Change-Id: I2da463e8b27e0db5cb1ba370d30f0402d7531396
Signed-off-by: Raj Mamadgi <r.mamadgi@samsung.com>
Added a test to make sure linker produces correct error message
when user attempts to load a library in a linked namespace and fails.
Bug: http://b/67866190
Bug: http://b/64950640
Bug: http://b/64888291
Test: bionic-unit-test --gtest_filter=dlext*
Change-Id: I5b5c2070d1388eff123118350b2b5c8fc7571a29
libdl is part of system_shared_libs now. -ldl -lpthread -lm are now defaults
for host_ldlibs on Linux and Darwin. -lrt is a default for host_ldlibs on
Linux.
Test: m host
Test: mmma bionic
Change-Id: I966e2f88c24fba5e412bee6b6382045a2026a8e4
With ld.config.txt, we now have multiple built-in namespaces other than
the default namespace. Libs (and their dependents) listed in LD_PRELOAD
must be visible to those additional namespaces as well.
This also adds a debugging only feature: path to the linker config file
can be customized via LD_CONFIG_FILE environment variable. This works
only for debuggable builds.
Bug: 38114603
Bug: 62815515
Test: 1. ./external/compiler-rt/lib/asan/scripts/asan_device_setup --lib
prebuilts/clang/host/linux-x86/clang-stable/lib64/clang/5.0/lib/linux
2. enable talkback shortcut
3. in the home screen, hold vol-up/down together
4. device does not reboots and talkback shortcut is toggled
Test: bionic-unit-tests and linker-unit-tests successful
Change-Id: I9a03591053f4a9caea82f0dcb23e7a3d324bb9bd
