We're still copy & pasting this workaround about, but the bug was supposedly fixed years ago!
Bug: http://b/34945607
Bug: http://b/33942619
Bug: http://b/34195559
Change-Id: Icf3d184d2ddb447dff7dacccea1dc903da816505
When the page_size < p_align of the ELF load segment, the loader
will end up creating extra PROT_NONE gap VMA mappings between the
LOAD segments. This problem is exacerbated by Android's zygote
model, where the number of loaded .so's can lead to ~30MB increase
in vm_area_struct unreclaimable slab memory.
Extend the LOAD segment VMA's to cover the range between the
segment's end and the start of the next segment, being careful
to avoid touching regions of the extended mapping where the offset
would overrun the size of the file. This avoids the loader
creating an additional gap VMA for each LOAD segment.
Consider a system with 4KB page size and the ELF files with 64K
alignment. e.g:
$ readelf -Wl /system/lib64/bootstrap/libc.so | grep 'Type\|LOAD'
Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x0441a8 0x0441a8 R 0x10000
LOAD 0x0441b0 0x00000000000541b0 0x00000000000541b0 0x091860 0x091860 R E 0x10000
LOAD 0x0d5a10 0x00000000000f5a10 0x00000000000f5a10 0x003d40 0x003d40 RW 0x10000
LOAD 0x0d9760 0x0000000000109760 0x0000000000109760 0x0005c0 0x459844 RW 0x10000
Before this patch:
$ cat /proc/1/maps | grep -A1 libc.so
7fa1d4a90000-7fa1d4ad5000 r--p 00000000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4ad5000-7fa1d4ae4000 ---p 00000000 00:00 0
7fa1d4ae4000-7fa1d4b76000 r-xp 00044000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4b76000-7fa1d4b85000 ---p 00000000 00:00 0
7fa1d4b85000-7fa1d4b8a000 r--p 000d5000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4b8a000-7fa1d4b99000 ---p 00000000 00:00 0
7fa1d4b99000-7fa1d4b9a000 rw-p 000d9000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4b9a000-7fa1d4feb000 rw-p 00000000 00:00 0 [anon:.bss]
3 additional PROT_NONE (---p) VMAs for gap mappings.
After this patch:
$ cat /proc/1/maps | grep -A1 libc.so
7f468f069000-7f468f0bd000 r--p 00000000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f0bd000-7f468f15e000 r-xp 00044000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f15e000-7f468f163000 r--p 000d5000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f163000-7f468f172000 rw-p 000da000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f172000-7f468f173000 rw-p 000d9000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f173000-7f468f5c4000 rw-p 00000000 00:00 0 [anon:.bss]
No additional gap VMAs. However notice there is an extra RW VMA at
offset 0x000da000. This is caused by the RO protection of the
GNU_RELRO segment, which causes the extended RW VMA to split.
The GNU_RELRO protection extension is handled in the subsequent
patch in this series.
Bug: 316403210
Bug: 300367402
Bug: 307803052
Bug: 312550202
Test: atest -c linker-unit-tests
Test: atest -c bionic-unit-tests
Change-Id: I7150ed22af0723cc0b2d326c046e4e4a8b56ad09
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
When the page_size < p_align of the ELF load segment, the loader
will end up creating extra PROT_NONE gap VMA mappings between the
LOAD segments. This problem is exacerbated by Android's zygote
model, where the number of loaded .so's can lead to ~30MB increase
in vm_area_struct unreclaimable slab memory.
Extend the LOAD segment VMA's to cover the range between the
segment's end and the start of the next segment, being careful
to avoid touching regions of the extended mapping where the offset
would overrun the size of the file. This avoids the loader
creating an additional gap VMA for each LOAD segment.
Consider a system with 4KB page size and the ELF files with 64K
alignment. e.g:
$ readelf -Wl /system/lib64/bootstrap/libc.so | grep 'Type\|LOAD'
Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x0441a8 0x0441a8 R 0x10000
LOAD 0x0441b0 0x00000000000541b0 0x00000000000541b0 0x091860 0x091860 R E 0x10000
LOAD 0x0d5a10 0x00000000000f5a10 0x00000000000f5a10 0x003d40 0x003d40 RW 0x10000
LOAD 0x0d9760 0x0000000000109760 0x0000000000109760 0x0005c0 0x459844 RW 0x10000
Before this patch:
$ cat /proc/1/maps | grep -A1 libc.so
7fa1d4a90000-7fa1d4ad5000 r--p 00000000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4ad5000-7fa1d4ae4000 ---p 00000000 00:00 0
7fa1d4ae4000-7fa1d4b76000 r-xp 00044000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4b76000-7fa1d4b85000 ---p 00000000 00:00 0
7fa1d4b85000-7fa1d4b8a000 r--p 000d5000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4b8a000-7fa1d4b99000 ---p 00000000 00:00 0
7fa1d4b99000-7fa1d4b9a000 rw-p 000d9000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7fa1d4b9a000-7fa1d4feb000 rw-p 00000000 00:00 0 [anon:.bss]
3 additional PROT_NONE (---p) VMAs for gap mappings.
After this patch:
$ cat /proc/1/maps | grep -A1 libc.so
7f468f069000-7f468f0bd000 r--p 00000000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f0bd000-7f468f15e000 r-xp 00044000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f15e000-7f468f163000 r--p 000d5000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f163000-7f468f172000 rw-p 000da000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f172000-7f468f173000 rw-p 000d9000 fe:09 20635520 /system/lib64/bootstrap/libc.so
7f468f173000-7f468f5c4000 rw-p 00000000 00:00 0 [anon:.bss]
No additional gap VMAs. However notice there is an extra RW VMA at
offset 0x000da000. This is caused by the RO protection of the
GNU_RELRO segment, which causes the extended RW VMA to split.
The GNU_RELRO protection extension is handled in the subsequent
patch in this series.
Bug: 316403210
Bug: 300367402
Bug: 307803052
Bug: 312550202
Test: atest -c linker-unit-tests [Later patch]
Test: atest -c bionic-unit-tests
Change-Id: I3363172c02d5a4e2b2a39c44809e433a4716bc45
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Instead of the hardcoded PAGE_SIZE 4096 macro, use the
real system page-size as queried from the auxillary vector.
Bug: 277272383
Bug: 300367402
Test: atest -c bionic-unit-tests
Change-Id: I2f1ad1b431e36ef45e9f53f713ced6b06e0d4f70
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
The close_range() test in particular has been confusing a lot of
partners. I think the sys_epoll_test.cpp idiom is the clearest of the
ones in use, so let's use that everywhere. (I haven't actually touched
the SysV IPC tests, because if we do touch them, _deleting_ them --
since all those syscalls are not allowed on Android -- is probably the
change to be made!)
I'm on the fence about factoring this idiom out into a macro. There
should never be too many of these, and we should probably be removing
them? Is anyone still running the current bionic tests on 4.3 kernels
without membarrier(2), and if they are --- why?!
For now though, I haven't removed any of our existing tests; I've just
moved them over to the sys_epoll_test.cpp style.
Test: treehugger
Change-Id: Ie69a0bb8f416c79957188e187610ff8a3c4d1e8f
Use cc_genrules to create the dlext test zips needed by the bionic
tests. The genrules aren't visible to Make, and so don't work with
the `required` property. Move all of the dependencies to `data_bins`,
`data_libs` or `data` for helper binaries, shared libraries or
genrule zip files respectively. The `data*` properties copy the
files into the same directory as a test, respecting the
`bionic-loader-test-libs` relative path specified by each, but
does not put each helper binary in its own subdirectory, so update
the paths in each of the tests.
Bug: 200872604
Test: atest CtsBionicTestCases
Test: atest bionic-unit-tests
Test: cts-tradefed run commandAndExit cts -m CtsBionicTestCases
Test: adb push $OUT/data/nativetest/bionic-unit-tests /data/nativetest/ && adb shell /data/nativetest/bionic-unit-tests/bionic-unit-tests
Change-Id: Ic4257cb4104ff558326df2363730acd20464b051
This flag is required to filter out shared VMAs when compacting memory
using process_madvise.
Test: atest bionic-unit-tests-static
Bug: 173258203
Change-Id: I01fc0cc614b03128a5a9b0a6c8c5c2d829b701f9
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
This reverts commit 01fb8d7120.
Reason for revert: Re-land the test after fixing b/156397945
Bug: 156397945
Change-Id: Ie9ec5fef7a308e28d512c6438c5c06758bdbcf06
Change the location set in the linker
Bug: 130219528
Bug: 138994281
Test: atest CtsBionicTestCases
Test: atest CtsJniTestCases
Change-Id: I215a8e023ccc4d5ffdd7df884c809f8d12050c8f
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
Historically we've made a few mistakes where they haven't matched the
right number. And most non-Googlers are much more familiar with the
numbers, so it seems to make sense to rely more on them. Especially in
header files, which we actually expect real people to have to read from
time to time.
Test: treehugger
Change-Id: I0d4a97454ee108de1d32f21df285315c5488d886
The executable flag might not be present for the executable segment
if the code is being handled by native bridge implementation. Old
heuristics for this case was to assume first segment is executable.
This doesn't stand any more. Instead, look for segment that contains
the function test is going to call.
Test: bionic-unit-tests --gtest_filter=dlext.ns_anonymous
Change-Id: I960bebba86e225d739b73f6d093e145fff17b4a8
This change makes it easier to diagnose mistakes in linker
configuration that result in a library being accidentally loaded in
multiple namespaces without its dependencies available everywhere.
Test: manually tested the error message
Test: bionic-unit-tests
Change-Id: I03a20507f8fc902c2445a7fbbf59767ffffd5ebf
Scudo creates a large map on 64 bit which can cause a slow down trying
to get the usage stats for all maps. Since the test only really cares
about a small subset of maps, only get the usage stats for those maps.
Test: Ran unit tests on scudo and jemalloc based systems.
Change-Id: Iba3cff1487ca304083aac323a3971b9f939f5c11
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
These are old enough now that the latest devices will have kernels that
support them.
Also add basic doc comments to <sys/mman.h>.
Test: treehugger
Change-Id: I1b5ff5db0b6270f5c374287cac1d6a751a0259f5
ANDROID_DLEXT_WRITE_RELRO was inadvertently writing out the RELRO
section of all libraries loaded during a given dlopen() call instead of
only the main library; since the other libraries are loaded at
unpredictable addresses this additional data is rarely useful.
Fix this to only happen when the
ANDROID_DLEXT_RESERVED_ADDRESS_RECURSIVE flag is being used.
Bug: 128623590
Test: DlExtRelroSharingTest.CheckRelroSizes
Change-Id: I05e8651d06ce2de77b8c85fe2b6238f9c09691ad
ANDROID_DLEXT_WRITE_RELRO was causing the GNU RELRO sections of
libraries to become corrupted if more than one library was being loaded
at once (i.e. if the root library has DT_NEEDED entries for libraries
that weren't already loaded). The file offset was not being correctly
propagated between calls, so after writing out the (correct) RELRO data
to the file, it was mapping the data at file offset 0 for all libraries,
which corrupted the data for all but one of the libraries.
Fix this by passing file_offset as a pointer the same way that
phdr_table_map_gnu_relro does.
Bug: 128623590
Test: tbd
Change-Id: I196cd336bd5a67454e89fd85487356b1c7856871
When built with clang-r353983, the ReservedRecursiveTooSmall test fail
due to the reserved memory is now large enough for android_dlopen_ext.
Reduce the reserved memory size to agree with ReservedTooSmall test.
Test: bionic-unit-tests
Bug: 126457671
Change-Id: I3e311a3f35b0de5d028fa1b9b3681d5ec32faee8
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
This reverts commit 1906e77665
and fixes dlopen(nullptr)
It's enabled for the following .so libraries
libicuuc.so
libicui18n.so
This CL does not move the .so files into a APEX.
Thus, no visible effect before moving .so files.
Bug: 121248172
Test: dlfcn#dlopen_from_nullptr
Test: Perform the following test after moving libicuuc to /apex
dlopen("/system/lib64/libicuuc.so") for targetSdkVersion < Q
Change-Id: Ia310ea566485fe00ca28e2203f4bffbd92243638
Use a global gtest isolation runner rather than the custom one in
bionic.
Test: Ran all unit tests and verified same behavior before and after.
Change-Id: I24a7cf17cf8e018d0f51969c64b53ce9059cc779
This check was not necessary since it is perfectly fine for a dso to
have any number of PT_LOAD segments, given that the number is > 0.
Bug: http://b/109747297
Test: make
Change-Id: I0e3b400fddf05ed7b9342bacbfffd3b578f26cf3
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
There were a bunch more unreasonable/incorrect ones, but these ones
seemed legit. Nothing very interesting, though.
Bug: N/A
Test: ran tests, benchmarks
Change-Id: If66971194d4a7b4bf6d0251bedb88e8cdc88a76f
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
