I'm removing the TODO on the assumption that being compatible with glibc
is more useful than BSD. The new internal "bionic_page.h" header factors
out some duplication between libc and the linker.
Bug: http://b/22735893
Change-Id: I4aec4dcba5886fb6f6b9290a8f85660643261321
When dlopen-ing a library, add the caller's DT_RUNPATH to the directory search
list. This fixes dlfcn.dt_runpath in bionic-unit-tests-glibc(32|64).
Bug: 21899363
Change-Id: Ife6a7e192939292cf4dc291b7e6b95945761cde3
There is possibility of someone dlclosing a library
while dl_iterate_phdr in progress which can lead to
dl_iterate_phdr calling callback with invalid address
if it was unmapped by dlclose.
Bug: http://b/22047255
Change-Id: I3fc0d9fd2c51fb36fd34cb035f37271fa893a7be
(cherry picked from commit f7d5bf334d)
Enables running of older MIPS NDK-built apps on mips64r6.
Works with kernel supporting FRE emulation, and old kernels.
Change-Id: If5e392ed89e9910cd1ccd30e0fd5c4a5acea2c7d
Enables running of older MIPS NDK-built apps on mips64r6.
Works with kernel supporting FRE emulation, and old kernels.
Change-Id: I13923fe62cd83ad1d337f13a50f2eda2dfdd906f
Do not skip RTLD_LOCAL libraries in dlsym(RTLD_DEFAULT, ...)
if the library is opened by application with target api level <= 22
Bug: http://b/21565766
Bug: http://b/17512583
Change-Id: Ic45ed1e4f53e84cba9d74cab6b0049c0c7aa8423
(cherry picked from commit 04f7e3e955)
This change adds realpath to soinfo and
extends limit on filenames from 128 to PATH_MAX.
It also removes soinfo::name field, linker uses
dt_soname instead.
Bug: http://b/19818481
Bug: https://code.google.com/p/android/issues/detail?id=80336
Change-Id: I9cff4cb5bda3ee2bc74e1bbded9594ea7fbe2a08
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
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
DT_STRSZ Implement strtab boundary checks
DT_FLAGS_1 Warn if flags other than DF_1_NOW|DF_1_GLOBAL are set
Bug: 17552334
Change-Id: Iaad29cd52f5b2d7d2f785fb351697906dc1617d9
This reverts commit 8f61d99183
Despite the fact that static linker does all the work while linking
-Bsymbolic executables, according to the SCO doc following DT_SYMBOLIC
and DF_SYMBOLIC flags is still a requirement for the dynamic linker
as well.
(see http://www.sco.com/developers/gabi/2012-12-31/ch5.dynamic.html)
Change-Id: I23f6a5e9b662e40cdbc462b64feff912431e800c
From the elf-spec: "Symbolically bound shared objects are
identified by the .dynamic entry DT_SYMBOLIC. This tag is
informational only; the runtime linker processes symbol
lookups from these objects in the same manner as any
other object."
Change-Id: I4aae0e502ed9fac096fbf076f4d6b2e055d784f6
Symbols from libraries opened with RTLD_LOCAL (default)
should not be visible via dlsym(RLTD_DEFAULT/RTLD_NEXT, .)
Bug: 17512583
Change-Id: I1758943081a67cf3d49ba5808e061b8251a91964
There are number of changes in the way IFUNC related relocations are done:
1. IRELATIVE relocations are now supported for x86/x86_64 and arm64.
2. IFUNC relocations are now relying on static linker to generate
them in correct order - this removes necessety of additional
relocation pass for ifuncs.
3. Related to 2: rela?.dyn relocations are preformed before .plt ones.
4. Ifunc are resolved on symbol lookup this approach allowed to avoid
mprotect(PROT_WRITE) call on r-x program segments.
Bug: 17399706
Bug: 17177284
Change-Id: I414dd3e82bd47cc03442c5dfc7c279949aec51ed
This patch fixes the problem with symbol search order
for dlsym(RTLD_DEFAULT/RTLD_NEXT, .) by loading libraries
and ld_preloads in correct order.
Bug: https://code.google.com/p/android/issues/detail?id=74255
Change-Id: If1ba5c807322409faa914e27ecb675e2c4541f0d
Attempt: 2
This patch fixes the problem with symbol search order
for dlsym(RTLD_DEFAULT/RTLD_NEXT, .) by loading libraries
and ld_preloads in correct order.
Bug: https://code.google.com/p/android/issues/detail?id=74255
Change-Id: I4cf84c70dbaabe99310230dfda12385ae5401859
This includes:
1. Placing has_ifunc after fields with version = 0
2. Switch to has_min_version(v) function.
3. Minor soinfo initialization refactoring (placement new + ctor)
Change-Id: I1bf5fde4d930914012ce5f3ad5acb48217da9b2d
ifuncs now work in i386 and x86_64 when called in the same library as
well as in a different library.
Bug:6657325
Change-Id: Ic0c48b1b0a76cb90f36c20c79f68294cc3fd44a1
dlsym(3) with handle != RTLD_DEFAULT|RTLD_NEXT performs
breadth first search through the dependency tree.
Bug: 16653281
Change-Id: I017a6975d1a62abb0218a7eb59ae4deba458e324
Linker is now able to resolve symlinked libraries correctly.
soinfo is extended to save the graph of dependencies during
load/unload. Dependencies are used only in CallConstructor.
Bug: 9741592
Change-Id: Id9c48a74c46aa89bcdf3d54ec2f8ba3d398130b1
Add a function "android_dlopen_ext()", defined in <android/dlext.h>.
This is an extended version of dlopen() which takes a struct for passing
additional parameters for Android-specific functionality. This will be
used to support RELRO section sharing between separate processes.
Bug: 13005501
Change-Id: I9c99b2f2a02ee329dedaeba09ef3a1113b17b2d6
Remove the linker's reliance on BSD cruft and use the glibc-style
ElfW macro. (Other code too, but the linker contains the majority
of the code that needs to work for Elf32 and Elf64.)
All platforms need dl_iterate_phdr_static, so it doesn't make sense
to have that part of the per-architecture configuration.
Bug: 12476126
Change-Id: I1d7f918f1303a392794a6cd8b3512ff56bd6e487
Also move some of the stuff that should be in <link.h> out of the
private "linker.h", to make it clearer that these are public API
known to gdb that we can't change.
Bug: 12554197
Change-Id: I830e1260d3d8b833ed99bc1518f1c6b6102be8af
Some system functions like munmap expect soinfo's size to be size_t, but currently
it is unsigned. Change it to size_t to fit 64bit's portability.
Change-Id: I0bf6d522b38b0cd9bf1db05b004b5326217412a2
Signed-off-by: Weiwu Chen <weiwu.chen@intel.com>
Signed-off-by: Qiming Shi <qiming.shi@intel.com>
We're not going to have init(1) set LD_LIBRARY_PATH globally on 64-bit.
This patch makes it possible for libnativehelper to set LD_LIBRARY_PATH
in each Java VM (to support System.loadLibrary) without also hard-coding
the default search path there.
Change-Id: If13961fae976e06dd80d5ef522f31e8b7eb01154
We don't need our own architecture macros; the standard ones will do.
This patch also fixes some __x86_64__ tests to be USE_RELA tests instead,
because they're not actually x86_64-specific.
I've cleaned up architecture-specific code slightly so where possible
all the code corresponding to a particular architecture is together.
This patch also fixes a bug in LP64 DT_PLTGOT handling, which should be
an error rather than falling through into DT_DEBUG! There was another #ifdef
bug where we'd only report unexpected DT_ entries on MIPS.
Change-Id: Id1d04e372611f641c1aa278a18e379f28af9eaf5
This matches glibc and makes life easier for developers who want to
sometimes preload a library from init (which has no conditionals); they
can simply move/remove the library to disable.
Change-Id: I579b8633f958235af6e46bb53b378b9e363afb1f
This adds __libc_fatal, cleans up the internal logging code a bit more,
and switches suitable callers over to __libc_fatal. In addition to logging,
__libc_fatal stashes the message somewhere that the debuggerd signal handler
can find it before calling abort.
In the debuggerd signal handler, we pass this address to debuggerd so that
it can come back with ptrace to read the message and present it to the user.
Bug: 8531731
Change-Id: I416ec1da38a8a1b0d0a582ccd7c8aaa681ed4a29
We only need one logging API, and I prefer the one that does no
allocation and is thus safe to use in any context.
Also use O_CLOEXEC when opening the /dev/log files.
Move everything logging-related into one header file.
Change-Id: Ic1e3ea8e9b910dc29df351bff6c0aa4db26fbb58
Still chipping away at the situation where every variable in the
linker was of type 'unsigned'. This patch switches counts over to
being size_t and adds an explicit type for init/fini function pointers
and arrays of function pointers.
Also improve logging from CallArray.
Also remove trailing "\n"s from log messages.
Change-Id: Ie036d2622caac50f4d29f0570888bb527661d77e
Replace a kernel header file dependency with files from NetBSD.
They're more complete, and ELF is ELF, whether you're on Linux or a BSD.
Bug: 7973611
Change-Id: I83ee719e7efdf432ec2ddbe8be271d05b2f558d7
We'll need a lot more refactoring of this code before we can reduce
the granularity, but this is a step forward.
Change-Id: I07061720e734b571a8399c1d5b4f2f35cd681307
Request memory from the system when needed instead of having a fixed
array for soinfo structs. Note that malloc() et al can't be used in
linker, so use mmap() instead.
Change-Id: I4b495995931d7752b0e8c944e64d1fe41b9f7144
If an executable contain copy relocations, other references
to the symbol it points to should be preempted and made to
point to the copy instead.
Also, the linker should make sure the target area has
sufficient space to contain the copy. It also checks
whether the library that supplies the symbol is built
with -Bsymbolic, and errors out if this is the case.
Change-Id: If135c83590092741cfd8f82f54816f363a4a4a3b
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@gmail.com>
I still want to break linker_format out into its own library so we can reuse
it for malloc debugging and so forth. (There are many similar pieces of code
in bionic, but the linker's one seems to be the most complete/functional.)
Change-Id: If3721853d28937c8e821ca1d23cf200e228a409a
This header is used on bionic build and should be propagated into
sysroot on toolchain rebuild. Discussion re. this header is here:
http://gcc.gnu.org/ml/gcc-patches/2012-08/msg00936.html
It is available already in mips NDK platforms:
development/ndk/platforms/android-9/arch-mips/include/link.h
Change-Id: I39ff467cdac9f448e31c11ee3e14a6200e82ab57
Signed-off-by: Pavel Chupin <pavel.v.chupin@intel.com>
The linker only needs to mark the text segment as
writable iff the file has text relocations. Unnecessarily
calling mprotect when it isn't necessary is slow, and some
security enhanced kernels don't like it. Pages which are
simultaneously writable and executable are considered a no-no.
The vast majority of executables / shared libraries on Android
do NOT have text relocations.
Change-Id: Ic38ce30a99b7e33ecf21efd9c108547a58eafa35
Also make the errors more readable, since none of us seemed to know
what they actually meant. The new style is still as verbose as the
old, but that's probably necessary in the absence of chained exceptions
in C. Here's what you'd see if you try to boot after removing
libsurfaceflinger.so:
32267 32267 E AndroidRuntime: java.lang.UnsatisfiedLinkError: Cannot load library: (linker.c:1629, pid 32259) soinfo_link_image: could not load library "libsystem_server.so" needed by "libandroid_servers.so"; caused by (linker.c:1629, pid 32259) soinfo_link_image: could not load library "libsurfaceflinger.so" needed by "libsystem_server.so"; caused by (linker.c:709, pid 32259) load_library: library "libsurfaceflinger.so" not found
This patch also fixes almost all of the compiler warnings.
Change-Id: I64bb59aed6d4e039c15ea45be2367f319ef879f8
Use the functions in linker_phdr.c to load the PT_LOAD segments
in memory, and toggle their mapping's writable protection bit
as needed. In particular:
- when loading a library, load the segments then unprotected
them to allow relocations to work.
- when relocating the linker of the executable, unprotect
the segments loaded by the kernel to make relocations work
too.
- after all relocations are done, re-protect the segments,
and apply GNU RELRO protection if needed.
- just before calling the destructors, undo the GNU RELRO
protection.
Change-Id: I50e709f03958204b8d6140c0f51ebe24fe089a1b
This patch changes the definition of the 'load_offset' field
in struct soinfo. The field is renamed because it is not the
basic load bias to add to every p_vaddr value read from the ELF
file to get the corresponding memory address.
This also slightly simplifies the relocation code.
+ Fix for proper load_bias computation for relocatable executables.
Change-Id: I72502c75a70751cba324deee7d313ae61f96609e
This patch introduces two new source files containing a set of functions
to manage the program header table in an ELF binary, including the ability
to load PT_LOAD segments, and apply PT_GNU_RELRO protection.
Note: the files are not used currently, this will appear in a series
of future patches that will gradually modify linker.c to use
the phdr_table_xxx functions properly.
Change-Id: Ia3d4c1ff5fc3e265d8258b64b492f4e643f51bdc
This patch adds to make the linker a little bit easier to understand
by making all functions that acts on a sofino object with a soinfo_
prefix.
This is to more easily distinguish functions that operate on global
state, and those that operate on individual libraries.
This should be purely stylistic, i.e. no feature/behaviour change.
Change-Id: Ie510d13d743aa4317644caefa9910b8af7e84f44
Before changing mmap() permission to PROT_NONE in alloc_mem_region(),
such libraries once worked with a bug that uses mmap'ed region outside of
memory region allocated by alloc_mem_region(). This possibly incurs
SIGSEGV because it can overwrite memory region of previously loaded
library, but it sometimes worked, depending on loading order.
After PROT_NONE, this caused SIGSEGV earlier during calculation of
si->phdr in load_library(), but this was fixed by:
75917c84d1 Use mmap to read an ...
Now the behaviour is the same as before applying PROT_NONE in
alloc_mem_region().
This CL fixed the original issue, supporting shared libraries that have
non-zero p_vaddr in first (= with lowest p_vaddr) PT_LOAD segment.
Bug: 6561258
Change-Id: Ib6176dd3e44c4d99a340eb1cbd16fb037586b0bc
Add support for PT_GNU_RELRO. This allows the static linker to
indicate that certain regions of memory should be marked as
"read-only" after dynamic linking is complete.
See:
* http://www.akkadia.org/drepper/nonselsec.pdf (section 6)
* http://tk-blog.blogspot.com/2009/02/relro-not-so-well-known-memory.html
Note that this change has no effect on Android right now, because
we don't compile our code with relro enabled.
Change-Id: I6541f8775367e8558b4388f7d105b1ae6e8f046b
We don't have a toolchain anymore, we don't have working original
kernel headers, and nobody is maintaining this so there is really
no point in keeping this here. Details of the patch:
- removed code paths from Android.mk files related to the SuperH
architecture ("sh")
- removed libc/arch-sh, linker/arch-sh, libc/kernel/arch-sh
- simplified libc/SYSCALLS.TXT
- simplified the scripts in libc/tools/ and libc/kernel/tools
Change-Id: I26b0e1422bdc347489e4573e2fbec0e402f75560
Signed-off-by: David 'Digit' Turner <digit@android.com>
This change makes linker handling of .preinit_array compliant with the
System V ABI:
"These [pre-initialization] functions are executed after the dynamic linker has
built the process image and performed relocations but before any shared object
initialization functions."
http://www.sco.com/developers/gabi/latest/ch5.dynamic.html#init_fini
Change-Id: Iebfee22bb1ebe1d7c7e69cb4686e4ebae0dfc4bb
Previously, the linker always loaded itself into the same
location in memory, which inhibited the effectiveness of Android's
ASLR implementation. Modify the linker code so it can be relocatable
and link itself at runtime.
Change-Id: Ia80273d7a00ff648b4da545f4b69debee6343968
Previously, the linker always loaded itself into the same
location in memory, which inhibited the effectiveness of Android's
ASLR implementation. Modify the linker code so it can be relocatable
and link itself at runtime.
Change-Id: I90d064743abdd29450ac0482ed28752b2196286c
