Add code to support loading shared libraries directly from within
APK files.
Extends the linker's handling of LD_LIBRARY_PATH, DT_RUNPATH, etc
to allow elements to be either directories as normal, or ZIP
format files. For ZIP, the ZIP subdirectory string is separated
from the path to file by '!'.
For example, if DT_NEEDED is libchrome.so and Chrome.apk is the
Android ARM APK then the path element
/system/app/Chrome.apk!lib/armeabi-v7a
would cause the linker to load lib/armeabi-v7a/libchrome.so
directly from inside Chrome.apk. For loading to succeed,
libchrome.so must be 'stored' and not compressed in Chrome.apk,
and must be page aligned within the file.
Motivation:
Chromium tracking issue:
https://code.google.com/p/chromium/issues/detail?id=390618
Bug: 8076853
Change-Id: Ic49046600b1417eae3ee8f37ee98c8ac1ecc19e7
Add basic general purpose memory allocator to
linker in order to enable usage of other libraries
like libziparchive.
Change-Id: I4a680ebb36ed5ba67c61249f81dba9f567808434
Kindle app relies on soinfo's sysv hash
fields while linking native libraries.
This change allows to keep sysv hash fields
intact for the libraries linked with --hash-style=both.
Bug: 19059885
Change-Id: I12528652955638f1a6586bda99e111bb1c8aa7a3
When the kernel executes a program which is setuid, setgid, has
file capabilities, or causes an SELinux domain transition, the
AT_SECURE flag is set. This flag instructs the dynamic linker to
prune any dangerous environment variables passed across security
boundaries.
For SELinux in particular, whether this flag is set depends on the
the "noatsecure" process permission. If that permission does not
exist, then AT_SECURE=1 whenever a domain transition occurs.
In https://android-review.googlesource.com/129971 , Android stopped
using noatsecure when executing init services. In
https://android-review.googlesource.com/130610 , init was flipped
back into SELinux enforcing mode, making ag/129971 active. The
combination of those two changes ensured that AT_SECURE=1 was
set when executing init spawned services.
In particular, AT_SECURE=1 is set when init executes zygote. Due to
the forking nature of zygote, AT_SECURE remains untouched when
executing zygote's children.
This causes problems for the code added in
https://android-review.googlesource.com/48409 . Specifically, if
AT_SECURE=1, an attempt to call android_update_LD_LIBRARY_PATH()
is silently ignored. This causes problems when art tries to adjust
the LD_LIBRARY_PATH for Android apps. Ultimately, apps are unable
to find shared libraries they depend on.
As discussed in bug 7896159, there's no security reason for
preventing an application from updating it's own LD_LIBRARY_PATH.
We only need to prune LD_LIBRARY_PATH when transitioning across
security boundaries, but not when we're entirely within a security
boundary.
Remove the AT_SECURE check within do_android_update_LD_LIBRARY_PATH().
It's unneeded and prevents an application from modifying it's own
LD_LIBRARY_PATH. This allows an application to specify a location
where it's dlopen()ed shared libraries should be loaded from.
There is no change to AT_SECURE handling in
__sanitize_environment_variables(). We continue to honor it there
to prevent using security sensitive environment variables across
an exec boundary.
Bug: 19559835
Change-Id: If4af2ee8e84265aaa0c93de8b281208b20d7942a
load_bias is the delta between a symbols address in memory and the value
contained in the symbol table.
Change-Id: I35c87b69025b64f7e4a1418ca766618f4533fb3e
Implement refcounter based data protection guard
to avoid unnecessary calls to mprotect when dlopen/dlclose
is called from a constructor.
Bug: 19124318
Big: 7941716
Change-Id: Id221b84ce75443094f99756dc9950b0a1dc87222
Handy when looking at strace output for seeing "where does my code start?",
though you'll need to set LD_DEBUG=1 (or greater) and constructors will
already have run (but you can set LD_DEBUG to a higher value to track that).
Change-Id: I82d53a7123b39febf5b2a956de83c8a30f229651
Position Independent Executables cannot communicate with GDB using DT_MIPS_RLD_TAG.
Hence a new tag DT_MIPS_RLD_MAP2 got introduced to fix the issue.
Change-Id: I77ce3faf1ef2e121003b804ecd291abb25cfbb56
Signed-off-by: Nikola Veljkovic<Nikola.Veljkovic@imgtec.com>
1. Take into consideration that the local_group_root_
is not set for all of not linked libraries.
2. We need to check visited list earlier to avoid double
soinfo_free.
Change-Id: Iabc0a06a97c63f7e6bd4641731f50bb1466fed4f
Count references on the group level to avoid
partially unloading function that might be
referenced by other libraries in the local_group
Bonus: with this change we can correctly unload recursively
linked libraries. is_recursive check is removed.
Also dynamic executables (not .so) with 0 DT_NEEDED libraries
are now correctly linked.
Change-Id: Idfa83baef402840599b93a875f2881d9f020dbcd
Relocate symbol against DF_1_GLOBAL shared libraries
loaded before this shared library. This includes
main executable, ld_preloads and other libraries
that have DF_1_GLOBAL flag set.
Bug: 2643900
Bug: 15432753
Change-Id: Ia788748be59b739d1c7e62b978e7e255f9e65c7b
The local group is a sequence of libraries in default (breadth-first)
order. It allows RTLD_LOCALLY loaded library to correctly relocate
symbols within its group (see test-cases).
Local group lookup is performed after main executable and ld_preloads.
Bug: 2643900
Bug: 15432753
Change-Id: I9bb013b46d17dbb5cbdfb8fef26f552748385541
replace lseek() and use pread() instead
add test for library_fd_offset > file_size case
Bug: 17762003
Change-Id: I4555f0be635124efe849c1f226985bcba72ffcbd
