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2021-05-11Merge "Add cc_defaults for hugepage alignment of shared libraries"Collin Fijalkovich
2021-05-06Bionic: Mark PMD aligned text segments huge page eligibleCollin Fijalkovich
To take advantage of file-backed huge pages for the text segments of key shared libraries (go/android-hugepages), the dynamic linker must load candidate ELF files at an appropriately aligned address and mark executable segments with MADV_HUGEPAGE. This patches uses segments' p_align values to determine when a file is PMD aligned (2MB alignment), and performs load operations accordingly. Bug: 158135888 Test: Verified PMD aligned libraries are backed with huge pages on supporting kernel versions. Change-Id: Ia2367fd5652f663d50103e18f7695c59dc31c7b9
2021-04-29Add cc_defaults for hugepage alignment of shared librariesCollin Fijalkovich
Introduces a cc_defaults category hugepage_aligned that passes the requisite linker flags to produce shared object files with 2MB-aligned sections. This enables supporting platforms to back the text segments of these libraries with hugepages. Bug: 158135888 Test: Built and confirmed ELF layout Change-Id: I5c8ce35d8f8bf6647ec19d58398740bd494cc89c
2021-03-19bp2build: remove some bp2build_available props, use package_allowlist instead.Jingwen Chen
Test: build/bazel/scripts/milestone-2/demo.sh full Test: bazel query //bionic/... Change-Id: I737574766be898279d8bf6f3f0adb43dcc40c220
2021-03-11Merge "Teach debuggerd to pass the secondary ring buffer to ↵Peter Collingbourne
__scudo_get_error_info()."
2021-03-09Merge "Add some slack at the end of large allocations when target SDK level ↵Peter Collingbourne
< S."
2021-03-05Add some slack at the end of large allocations when target SDK level < S.Peter Collingbourne
This works around buggy applications that read a few bytes past the end of their allocation, which would otherwise cause a segfault with the concurrent Scudo change that aligns large allocations to the right. Because the implementation of android_set_application_target_sdk_version() lives in the linker, we need to introduce a hook so that libc is notified when the target SDK version changes. Bug: 181344545 Change-Id: Id4be6645b94fad3f64ae48afd16c0154f1de448f
2021-03-02Ignore LD_LIBRARY_PATH when determining file type in ldd.Pete Bentley
Otherwise if a 32bit copy of a library used by Toybox exists on LD_LIBRARY_PATH then file(1) will fail. Bug: 181666541 Test: Manually copied to device and verified correct behaviour Change-Id: I7d729927b1b433ec953c266920489613fc096e03
2021-02-19Add LOCAL_LICENSE_KINDS to bionicBob Badour
Added SPDX-license-identifier-Apache-2.0 to: apex/Android.bp libdl/Android.bp tools/Android.bp tools/versioner/Android.bp tools/versioner/src/Android.bp Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD to: benchmarks/Android.bp benchmarks/linker_relocation/gen/Android.bp libc/malloc_debug/Android.bp libc/system_properties/Android.bp tests/Android.bp tests/libs/Android.bp tests/libs/Android.build.dlext_testzip.mk tests/make_fortify_compile_test.mk Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD SPDX-license-identifier-ISC SPDX-license-identifier-MIT legacy_notice legacy_unencumbered to: libc/Android.bp Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD SPDX-license-identifier-MIT legacy_unencumbered to: libm/Android.bp Added SPDX-license-identifier-Apache-2.0 legacy_unencumbered to: libc/tools/Android.bp Added SPDX-license-identifier-BSD to: benchmarks/linker_relocation/Android.bp benchmarks/spawn/Android.bp libc/async_safe/Android.bp libc/malloc_hooks/Android.bp libfdtrack/Android.bp linker/Android.bp tests/headers/Android.bp tests/headers/posix/Android.bp Bug: 68860345 Bug: 151177513 Bug: 151953481 Test: m all Exempt-From-Owner-Approval: janitorial work Change-Id: Ib05bcaa276b3aa71a7654ccbe8e67e1f16aec9f3
2021-02-18Rename ldd input file to ldd.sh to make Bazel conversion easier.Rupert Shuttleworth
Test: m and bp2build write; bazel build ... Change-Id: Ic8a4ad6ac81f034ac8b9736d99a322c48598619e
2021-02-17Merge "Fix/update notices."Elliott Hughes
2021-02-17Merge "Revert "[LSC] Add LOCAL_LICENSE_KINDS to bionic""Bob Badour
2021-02-16Fix/update notices.Elliott Hughes
Auto-generate NOTICE files for all the directories, and for each one individually rather than mixing libc and libm together. Test: N/A Change-Id: I7e251194a8805c4ca78fcc5675c3321bcd5abf0a
2021-02-16Revert "[LSC] Add LOCAL_LICENSE_KINDS to bionic"Elliott Hughes
This reverts commit 48d43034d7b5a419ba56f052856696d53a7bd979. Reason for revert: bionic is multiple projects, not just one. Change-Id: Ib31e1bb8888cc85c6e7736c4e2a1d4652fd23935
2021-02-16Mark ldd as executable for Bazel builds to work.Rupert Shuttleworth
Test: bazel build ... Change-Id: I15f23804ab1ef44cc0a68b66c408dd88366f8098
2021-02-12[LSC] Add LOCAL_LICENSE_KINDS to bionicBob Badour
Added SPDX-license-identifier-Apache-2.0 to: libdl/Android.bp tools/versioner/src/Android.bp Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD to: benchmarks/Android.bp libc/malloc_debug/Android.bp libc/system_properties/Android.bp linker/Android.bp tests/Android.bp tests/libs/Android.bp tests/libs/Android.build.dlext_testzip.mk tests/make_fortify_compile_test.mk Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD SPDX-license-identifier-ISC SPDX-license-identifier-MIT legacy_notice legacy_unencumbered to: Android.bp libc/Android.bp Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD SPDX-license-identifier-ISC SPDX-license-identifier-MIT legacy_unencumbered to: tools/Android.bp tools/versioner/Android.bp Added SPDX-license-identifier-Apache-2.0 SPDX-license-identifier-BSD SPDX-license-identifier-MIT legacy_unencumbered to: libm/Android.bp Added SPDX-license-identifier-Apache-2.0 legacy_unencumbered to: libc/tools/Android.bp Added SPDX-license-identifier-BSD to: benchmarks/linker_relocation/Android.bp benchmarks/spawn/Android.bp libc/async_safe/Android.bp libc/malloc_hooks/Android.bp libfdtrack/Android.bp tests/headers/Android.bp tests/headers/posix/Android.bp Added legacy_notice to: apex/Android.bp benchmarks/linker_relocation/gen/Android.bp Bug: 68860345 Bug: 151177513 Bug: 151953481 Test: m all Exempt-From-Owner-Approval: janitorial work Change-Id: I76cad00578b9b99180ee5dd1e04b4646d5c5fedf
2021-02-12Teach debuggerd to pass the secondary ring buffer to __scudo_get_error_info().Peter Collingbourne
With this change we can report memory errors involving secondary allocations. Update the existing crasher tests to also test UAF/overflow/underflow on allocations with sizes sufficient to trigger the secondary allocator. Bug: 135772972 Change-Id: Ic8925c1f18621a8f272e26d5630e5d11d6d34d38
2021-02-09Mark sh_binary target as being bp2build_available.Rupert Shuttleworth
Test: build/bazel/scripts/bp2build-sync.sh write. Change-Id: I8e8c3c95aa2c7ff6d7db3d92291f224bdf7cf255
2021-01-28Fix -Wl,--exclude-libs typo: x86->i686Ryan Prichard
These lines shouldn't actually matter, because the DSOs are using version scripts to allow-list exported symbols. Bug: none Test: bionic unit tests Change-Id: I39d3df8c4f8053624f862b3c6994e30c693e928c
2021-01-22Ensure same order of global group members in all NS'sRyan Prichard
During "step 1" of find_libraries, the linker finds the transitive closure of dependencies, in BFS order. As it finds each library, it adds the library to its primary namespace (so that, if some other library also depends on it, find_loaded_library_by_soname can find the library in the process of being loaded). LD_PRELOAD libraries are automatically marked DF_1_GLOBAL, and any DF_1_GLOBAL library is added to every linker namespace. Previously, this secondary namespace registration happened after step 1. The result is that across different namespaces, the order of libraries could vary. In general, a namespace's primary members will all appear before secondary members. This is undesirable for libsigchain.so, which we want to have appear before any other non-preloaded library. Instead, when an soinfo is added to its primary namespace, immediately add it to all the other namespaces, too. This ensures that the order of soinfo objects is the same across namespaces. Expand the dl.exec_with_ld_config_file_with_ld_preload and dl.exec_with_ld_config_file tests to cover the new behavior. Mark lib1.so DF_1_GLOBAL and use a "foo" symbol to mimic the behavior of a signal API interposed by (e.g.) libsigchain.so and a ASAN preload. Test: bionic unit tests Bug: http://b/143219447 Change-Id: I9fd90f6f0d14caf1aca6d414b3e9aab77deca3ff
2021-01-20Merge "Switch libc.so and linker to prebuilt LLVM libunwind"Ryan Prichard
2021-01-19Inline call_array for clearer stack traces.Elliott Hughes
No-one seems to understand that a crash in a random .so from call_array() in the linker isn't a linker bug. They _seem_ to understand (or at least claim to) when we explain that this is just the linker calling their ELF constructors --- despite the fact that the caller of call_array() is call_constructors(). One experiment we can try though is to inline call_array() to elide that frame from the crash dumps. I do also wonder whether renaming call_constructors() to call_elf_constructors() would help/hinder/make no difference. For now I'm leaning toward "hinder" because I suspect most people don't understand "ELF constructor" and C++ folks at least will probably be influenced in a not wholly incorrect direction when they hear "constructor" (whereas "ELF constructor" might mislead them back in the direction of "strange linker magic, not my fault" again)... (The reformatting is clang-format's decision, not mine.) Test: treehugger Change-Id: I65ab95ceb2e988fd053c48c66f51afba17ccfa61
2021-01-14Switch libc.so and linker to prebuilt LLVM libunwindRyan Prichard
For libc.so, use a special build of libunwind.a whose symbols aren't hidden ("libunwind-exported"), because libc.so exports the _Unwind_* APIs. Bug: http://b/153025717 Test: bionic unit tests Change-Id: I7435e076ec8cc4410e3e6086d3cf5d2c6011c80c
2021-01-13Delay setting linker soname until post-reloc and post-ctorRyan Prichard
Setting the linker's soname ("ld-android.so") can allocate heap memory now that the name uses an std::string, and it's probably a good idea to defer doing this until after the linker has relocated itself (and after it has called C++ constructors for global variables.) Bug: none Test: bionic unit tests Test: verify that dlopen("ld-android.so", RTLD_NOLOAD) works Change-Id: I6b9bd7552c3ae9b77e3ee9e2a98b069b8eef25ca
2021-01-11Store soname as a std::string.Elliott Hughes
Once upon a time (and, indeed, to this very day if you're on LP32) the soinfo struct used a fixed-length buffer for the soname. This caused some issues, mainly with app developers who accidentally included a full Windows "C:\My Computer\...\libfoo.so" style path. To avoid all this we switched to just pointing into the ELF file itself, where the DT_SONAME is already stored as a NUL-terminated string. And all was well for many years. Now though, we've seen a bunch of slow startup traces from dogfood where `dlopen("libnativebridge.so")` in a cold start takes 125-200ms on a recent device, despite no IO contention. Even though libnativebridge.so is only 20KiB. Measurement showed that every library whose soname we check required pulling in a whole page just for the (usually) very short string. Worse, there's readahead. In one trace we saw 18 pages of libhwui.so pulled in just for `"libhwui.so\0"`. In fact, there were 3306 pages (~13MiB) added to the page cache during `dlopen("libnativebridge.so")`. 13MiB for a 20KiB shared library! This is the obvious change to use a std::string to copy the sonames instead. This will dirty slightly more memory, but massively improve locality. Testing with the same pathological setup took `dlopen("libnativebridge.so")` down from 192ms to 819us. Bug: http://b/177102905 Test: tested with a pathologically modified kernel Change-Id: I33837f4706adc25f93c6fa6013e8ba970911dfb9
2021-01-06Use ELF notes to set the desired memory tagging level.Evgenii Stepanov
Use a note in executables to specify (none|sync|async) heap tagging level. To be extended with (heap x stack x globals) in the future. A missing note disables all tagging. Bug: b/135772972 Test: bionic-unit-tests (in a future change) Change-Id: Iab145a922c7abe24cdce17323f9e0c1063cc1321
2020-12-09linker: Enable PGOYi Kong
linker-reloc-bench shows 1.2% improvement on flame. PGO No PGO BM_linker_relocation/ real_time_mean 52215 us 52916 us Test: linker-reloc-bench --benchmark_repetitions=25 Bug: 175205560 Change-Id: I6abbbd51912f86fcf8112c024d1cf2519056bea7
2020-11-06linker: add ld.config.txt parse time to systrace.Elliott Hughes
Bug: http://b/172640358 Test: treehugger Change-Id: I9d6b7c1e200d2effb737508d3c282063edefa888
2020-10-29Merge "Make vendor_ramdisk_available."Yifan Hong
2020-10-27Make vendor_ramdisk_available.Yifan Hong
Test: pass Bug: 156098440 Change-Id: I8fe2deb8fa3b24c227202be02d8af648629cffeb
2020-10-01No global ThinLTO for linkerYi Kong
Previous CL aosp/1432874 missed one project to exclude. Test: make Change-Id: Ib39e6a86c410e35141cba17948a0f30e197ea9a3
2020-09-29No global ThinLTO for bionicYi Kong
There are multiple build breakages with bionic when we enable ThinLTO globally. Opt bionic out of ThinLTO for now. #global-thinlto-opt-out Test: TreeHugger Bug: 169004486 Change-Id: I546a8074f9c3e0ddbd01d3b7cd730e215e3c0c49
2020-09-23Enable BTI in bionic linkerTamas Petz
This patch adds support to load BTI-enabled objects. According to the ABI, BTI is recorded in the .note.gnu.property section. The new parser evaluates the property section, if exists. It searches for .note section with NT_GNU_PROPERTY_TYPE_0. Once found it tries to find GNU_PROPERTY_AARCH64_FEATURE_1_AND. The results are cached. The main change in linker is when protection of loaded ranges gets applied. When BTI is requested and the platform also supports it the prot flags have to be amended with PROT_BTI for executable ranges. Failing to add PROT_BTI flag would disable BTI protection. Moreover, adding the new PROT flag for shared objects without BTI compatibility would break applications. Kernel does not add PROT_BTI to a loaded ELF which has interpreter. Linker handles this case too. Test: 1. Flame boots 2. Tested on FVP with BTI enabled Change-Id: Iafdf223b74c6e75d9f17ca90500e6fe42c4c1218
2020-09-22Add arm64 source to linker_wrapperJiyong Park
As we enable arm64-based Bionic host target (linux_bionic_arm64), linker_wrapper is added with the corresponding source. Bug: 159685774 Test: HOST_CROSS_OS=linux_bionic HOST_CROSS_ARCH=arm64 m Test: copy out/soong/host/linux_bionic_arm64/ to an ARM64 emulator running Linux and execute the binaries Change-Id: I4f367a349f7e0015318352cb7f2870fc856eab05
2020-08-11Add a thread-properties APIVy Nguyen
(Based on proposal at https://sourceware.org/glibc/wiki/ThreadPropertiesAPI) This includes API to: - locate static and dynamic TLS - register thread-exit and dynamic TLS creation/destruction callbacks Change-Id: Icd9d29a5b2f47495395645e19d3b2c96826f19c8
2020-08-03Rename linker greylist to exempt-listRyan Prichard
Update a comment in android-changes-for-ndk-developers.md about the removed debug.ld.greylist_disabled system property. Update language to comply with Android's inclusive language guidance #inclusivefixit See https://source.android.com/setup/contribute/respectful-code for reference Bug: http://b/162536543 Test: bionic-unit-tests Change-Id: I760ee14bce14d9d799926c43d2c14fd8ffbc6968
2020-08-02Merge "linker: Cleanup for Android's inclusive language guidance"Treehugger Robot
2020-07-31linker: Cleanup for Android's inclusive language guidanceLuke Huang
1. Cleanup for #inclusivefixit. (whitelisted -> allowed_libs) 2. Support the old term for backwards compatibility. (Also update test.) 3. Fix the formatting errors found by clang-format. See https://source.android.com/setup/contribute/respectful-code for reference. Bug: 161896447 Test: atest linker-unit-tests linker-benchmarks Change-Id: I19dbed27a6d874ac0049cb7b67d2cb0f75369c1b
2020-07-30Remove debug.ld.greylist_disabled propertyRyan Prichard
This property provided a way to disable the greylist, for testing whether an app targeting < 24 still works. Instead of turning off the greylist, though, an app developer should simply target a newer API. (If app developers really need this property for testing, they can still use it on versions of Android between N and R, inclusive.) Update language to comply with Android's inclusive language guidance See https://source.android.com/setup/contribute/respectful-code for reference #inclusivefixit Bug: http://b/162536543 Test: bionic-unit-tests Change-Id: Id1eb2807fbb7436dc9ed7fe47e15b7d165a26789
2020-07-21Changes for #inclusivefixit.Elliott Hughes
Test: treehugger Change-Id: I7ff0496c5c2792a41781e74634247f55b0548213
2020-07-16Pagetable-friendly shared library address randomization.Evgenii Stepanov
Add inaccessible gaps between shared libraries to make it harder for the attackers to defeat ASLR by random probing. To avoid excessive page table bloat, only do this when a library is about to cross a huge page boundary, effectively allowing several smaller libraries to be lumped together. Bug: 158113540 Test: look at /proc/$$/maps Change-Id: I39c0100b81f72447e8b3c6faafa561111492bf8c
2020-07-06Merge "Revert "Add randomized padding around shared library mappings.""Evgenii Stepanov
2020-07-06Revert "Add randomized padding around shared library mappings."Evgenii Stepanov
This reverts commit a8cf3fef2aa2201014c35c3487da222ccfedfc1c. Reason for revert: memory regression due to the fragmentation of the page tables Bug: 159810641 Bug: 158113540 Change-Id: I6212c623ff440c7f6889f0a1e82cf7a96200a411
2020-06-30Disable warning message for missing linker config in some casesKiyoung Kim
There are some special cases - such as init process - when linker configuration is not expected to exist. This change disables warning message that generated linker configuration does not exist in those cases. Bug: 158800902 Test: Tested from cuttlefish that warning message is not generated from init Change-Id: Ie2fbb5210175cf1e6f2b7e638f57c3b74d395368
2020-06-17Add randomized padding around shared library mappings.Evgenii Stepanov
Improve ASLR by increasing the randomly sized gaps between shared library mappings, and keep them mapped PROT_NONE. Bug: 158113540 Test: look at /proc/$$/maps Change-Id: Ie72c84047fb624fe2ac8b7744b2a2d0d255ea974
2020-06-12Use PROT_NONE on the unused parts of CFI shadow.Evgenii Stepanov
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
2020-06-10linker: CHECK() or async_safe_fatal() rather than abort().Elliott Hughes
In particular, add the strerror() output if mprotect() fails. Fix the CHECK macro so that you can make assertions involving operator% without that being confused for a printf format specifier. Bug: https://issuetracker.google.com/158645318 Test: treehugger Change-Id: I6817f8ca5f094c52dc2c9067bfac90385a8743f5
2020-06-02Make .whitelisted property "append"-ableJooyung Han
.whitelisted is a list of sonames seperated by ":" just like .shared_libs and .paths properties. It makes sense to make it appendable using += as well ass .shared_libs and .paths. Bug: n/a Test: atest linker-unit-tests Change-Id: If61cc553c8080e8a58de8a3a6051c1853f7bfe5f
2020-05-19Refactor translateSystemPathToApexPathVictor Khimenko
This is more efficient and easier to read. Test: bionic-unit-tests --gtest_filter=*icu* Change-Id: Iddeed7cd4a1d48d8968f97951a9af004ccce52e8
2020-05-15Allow native_bridge linker to use different APEX from native oneVictor Khimenko
Bug: http://b/156397945 Test: dlfcn.dlopen_system_libicuuc_android_api_level_28 with native_bridge Change-Id: I3ecd929a0c31dda8cd424795f21f6ef472776557
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-03 08:46:29 +0000