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
Get dynamic flags from phdr table's correct entry rather the first
entry, so that the following DT_DEBUG entry can be set.
Also fix the undefined reference to LoadTask::deleter issue under gcc
-O0 option.
Bug: 17524778
Change-Id: I9c679af197b034761fb739d6c980e628ff2ab84c
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
Expanded test for recursive libs. Fixed bug with unnecessary
soinfo_free of already loaded library.
Change-Id: I2cc19f2650c8b12a35feeac127ef608ebba44d88
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
Enable the -std=gnu++11 flag for libstdc++ static and
dynamic libs.
ScopeGuard uses DISABLE_ macros instead of '= delete';
Change-Id: I07e21b306f95fffd49345f7fa136cfdac61e0225
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
Change lookup order during relocation so that
ld_preloads always precede caller (unless caller
is main executable).
Asan needs this change in order to intercept libc->libc
calls.
Bug: 15432753
(cherry picked from commit 05e190c093)
Change-Id: I5bfb58e18015b1ec5b77842dbb37fb122fa1fd1a
When enabling debug malloc, the snprintf calls in the linker fails to
update the buffer.
The problem is that snprintf makes a call to pthread_getspecific that
returns a valid pointer, but the data it points to is zero. This should
never happen and causes the snprintf to stop and do nothing.
Temporarily replace snprintf with a different implementation to work
around this issue.
Bug: 16874447
Bug: 17302493
(cherry pick from commit 172955a4e3)
Change-Id: Idca9d417978403d61debfd0434aaa82fd770f33b
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
Do not run symbol lookup on already visited soinfos
Not taking into account already visited libraries
dramatically slows down dlsym in cases when there
are multiple occurrences of a large library in
dependency tree.
Bug: 16977077
Change-Id: I1379f30ed8b06758dd1cc76b80833ac8589afa50
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
/system/bin/tf_daemon on Nakasi has been updated so it's
a PIE executable. We can now drop non-PIE support.
This reverts commit d81b3b275d.
Bug: 15086752
Bug: 15732002
Bug: 14566672
Change-Id: I832c4de01a8fa050754ea64da317d1639990265e
On Nakasi builds, /system/bin/tf_daemon is a pre-compiled
vendor supplied binary. When support for non-PIE executables
was removed, that daemon failed to start, which induced
a number of bugs.
* keystore is broken
* CTS runs will hang after a certain period of time
Temporarily reenable non-PIE support for 32-bit platforms
until Nakasi is fixed.
This rolls back the following commits:
Cleanup: updated comments
* 6275f20834
Cleanup: remove AARCH/ARM_COPY relocation support
* b906e13c55
And restricts the following patch to 64 bit only:
Remove support for non-PIE executables
* 2aebf5429b
Bug: 14566672
Bug: 15086752
Bug: 15732002
Change-Id: Ia2501aa14bd30feb4a6ce66bdb7c9f066dba0b5f
While introducing RTLD_NOLOAD in b648a8a5 a change in how soinfo structs are
connected was also introduced. When calling dlopen the library that is loaded
is added as a child to the soinfo from which the caller comes - i.e. building a
dependency graph.
Unfortunately this shows issues upon unloading, such as blowing the stack if
there are loops in the graph.
This change reverts that part of b648a8a5, keeping everything as a child of the
root soinfo.
Change-Id: I604ee9210613b19f693a568158e69707620a95db
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
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
Don't support the dynamic linker loading ET_EXEC executables. Only
support ET_DYN executables.
Bug: 14566672
Change-Id: Ia1f2bfffe7ea867c1cd62e67d7fd637c60c0728d
Add missing second param to soinfo_link_image in a section that's not
compiled on ARM.
Bug: 13005501
Change-Id: Id0ede8e03da4e05b25c0aeb24a840f868031d4e8
Add flags and a file descriptor to android_dlopen_ext() to allow writing
the RELRO section of the loaded library to a file after relocation
processing, and to allow mapping identical pages from the file over the
top of relocated memory in another process. Explicitly comparing the
pages is required in case a page contains a reference to a symbol
defined in another library loaded at a random base address.
Bug: 13005501
Change-Id: Ibb5b2d384edfaa5acf3e97a5f8b6115c10497a1e
Add flags and parameters to android_dlopen_ext() to allow loading a
library at an already-reserved fixed address. If the library to be
loaded will not fit within the space reserved, then the linker will
either fail, or allocate its own address space as usual, according to
which flag has been specified. This behaviour only applies to the
specific library requested; any other libraries loaded as dependencies
will be loaded in the normal fashion.
There is a new gtest included to cover the functionality added.
Bug: 13005501
Change-Id: I5d1810375b20fc51ba6a9b3191a25f9792c687f1
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
When bionic's dynamic linker processes the .dynamic section of a MIPS ELF binary and encounters the DT_MIPS_RLD_MAP dynamic array tag, it calculates the address of where to write a pointer to the _r_debug structure. The current implementation simply reads the value given in the d_ptr field and writes the pointer address to that location. However, this value has to be adjusted to reflect the real load address of the binary. Otherwise the linker will write to a faulty location possibly resulting in a crash when linking a MIPS binary that includes DT_MIPS_RLD_MAP. This change corrects that problem.
Change-Id: I1a91874f7ab47289001fe72d9016660c14c70362
Signed-off-by: Benjamin Adolphi <b.adolphi@gmail.com>
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
If the linker can't resolve its own internal references to symbols,
we currently exit silently (albeit with EXIT_FAILURE). Not very helpful.
Change-Id: I1614fc970dee4560b38832ede1987b65a8e53a1e
Addition of support for AArch64 in the linker64 target.
Change-Id: I8dfd9711278f6706063e91f626b6007ea7a3dd6e
Signed-off-by: Marcus Oakland <marcus.oakland@arm.com>
Under valgrind ehdr_vdso is null and causing segfault.
Adding debug info for vdso producing plenty of issues on debugging
through gdbserver, removing it. It doesn't seem it should be here.
Unwinding through vdso test still works.
Change-Id: I1a7e233c493f2268d725fa8d7279822d07decc49
Signed-off-by: Pavel Chupin <pavel.v.chupin@intel.com>
Integration of kernel VDSO into internal bionic data structures using
common functions.
Fix for dl_iterate_phdr function: the function provides incorrect
address of object in case of nonzero virtual and base addresses.
Location in address space of a particular program header should be
calculated using the formula: addr = base_addr + virtual_addr.
Signed-off-by: Sergey Melnikov <sergey.melnikov@intel.com>
Change-Id: Ie2ab4257fd456242aab8afed0bd5bd6b29e81d6d
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
The x86_64 build was failing because clone.S had a call to __thread_entry which
was being added to a different intermediate .a on the way to making libc.so,
and the linker couldn't guarantee statically that such a relocation would be
possible.
ld: error: out/target/product/generic_x86_64/obj/STATIC_LIBRARIES/libc_common_intermediates/libc_common.a(clone.o): requires dynamic R_X86_64_PC32 reloc against '__thread_entry' which may overflow at runtime; recompile with -fPIC
This patch addresses that by ensuring that the caller and callee end up in the
same intermediate .a. While I'm here, I've tried to clean up some of the mess
that led to this situation too. In particular, this removes libc/private/ from
the default include path (except for the DNS code), and splits out the DNS
code into its own library (since it's a weird special case of upstream NetBSD
code that's diverged so heavily it's unlikely ever to get back in sync).
There's more cleanup of the DNS situation possible, but this is definitely a
step in the right direction, and it's more than enough to get x86_64 building
cleanly.
Change-Id: I00425a7245b7a2573df16cc38798187d0729e7c4
Kernel provides virtual DSO for stack unwinding/exception handlind info for
signal usage case. Stack unwinding routines use 'dl_iterate_phdr' function
for additional DWARF info gathering from DSOs. Patch enables virtual DSO
enumeration via dl_iterate_phdr function.
Signed-off-by: Sergey Melnikov <sergey.melnikov@intel.com>
Change-Id: Ic2882b28f40b456a088bc1e63c50cbfda7e4a102
Text relocations unnecessarily mark pages as dirty, preventing them
from being swapped out, wasting memory. Also, text relocations
prevent the code from running on certain hardened systems.
Print a message in logcat and stderr when we see a text relocation,
to encourage developers to fix their code.
Change-Id: I6051a7463911e090ae5727a355397d539669d5b9
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
The GNU dynamic linker silently ignores a DT_PREINIT_ARRAY section
in a shared library. We had ineffectual code that tried to report
an error, which I tried to fix but got wrong --- my version still
wouldn't report the error to the caller, but would prevent us from
continuing to call constructors.
Bug: 8825226
Change-Id: I4fd8450ecc44d8767a1cb808aeecfbfbfc77c070
get_AT_SECURE() was getting called before linker_env_init() had
been called, and returning the default value ("true"). This was
causing us to reopen closed stdin, stdout, and stderr for ALL
processes, not just privileged (setuid) processes.
Calling path:
- __linker_init
- soinfo_link_image
- get_AT_SECURE
- __linker_init_post_relocation
- linker_env_init
This change restores the intended behavior of only re-opening
stdin, stdout, and stderr for privileged processes.
Change-Id: I8b085ea6597710ac4c1a3c93f1bf8b81eecb08c0
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
There's now only one place where we deal with this stuff, it only needs to
be parsed once by the dynamic linker (rather than by each recipient), and it's
now easier for us to get hold of auxv data early on.
Change-Id: I6314224257c736547aac2e2a650e66f2ea53bef5
We had two copies of the backtrace code, and two copies of the
libcorkscrew /proc/pid/maps code. This patch gets us down to one.
We also had hacks so we could log in the malloc debugging code.
This patch pulls the non-allocating "printf" code out of the
dynamic linker so everyone can share.
This patch also makes the leak diagnostics easier to read, and
makes it possible to paste them directly into the 'stack' tool (by
using relative PCs).
This patch also fixes the stdio standard stream leak that was
causing a leak warning every time tf_daemon ran.
Bug: 7291287
Change-Id: I66e4083ac2c5606c8d2737cb45c8ac8a32c7cfe8
The AT_RANDOM changes broke setuid / setgid executables
such as "ping". When the linker executes a setuid program,
it cleans the environment, removing any invalid environment
entries, and adding "NULL"s to the end of the environment
array for each removed variable. Later on, we try to determine
the location of the aux environment variable, and get tripped
up by these extra NULLs.
Reverting this patch will get setuid executables working again,
but getauxval() is still broken for setuid programs because of
this bug.
This reverts commit e3a49a8661.
Change-Id: I05c58a896b1fe32cfb5d95d43b096045cda0aa4a
Populate the stack canaries from the kernel supplied
AT_RANDOM value, which doesn't involve any system calls.
This is slightly faster (6 fewer syscalls) and avoids
unnecessarily reading /dev/urandom, which depletes entropy.
Bug: 7959813
Change-Id: If2b43100a2a9929666df3de56b6139fed969e0f1
This is primarily for MIPS exutables that do not have a
DT_MIPS_RLD_MAP entry.
Change-Id: I4c221d92debcfed961eeee2515123f3fb21ec8e6
Signed-off-by: Chris Dearman <chris@mips.com>
If you need to build your own linker to get debugging, the debugging
is never available when you need it.
Change-Id: I5ff7e55753459d49a2990f25d9aa155e0b8602e0
According ELF spec re. DT_SYMBOLIC:
This element's presence in a shared object library alters the dynamic
linker's symbol resolution algorithm for references within the library.
Instead of starting a symbol search with the executable file, the
dynamic linker starts from the shared object itself. If the shared
object fails to supply the referenced symbol, the dynamic linker then
searches the executable file and other shared objects as usual.
This change implements the last part.
Change-Id: Iae95d53d455313a4306f11733941bcd3596ac85f
Signed-off-by: Pavel Chupin <pavel.v.chupin@intel.com>
NVIDIA binary blobs construct strings to pass to dlopen(3) that
contain '/' but require that we fall back to LD_LIBRARY_PATH.
Change-Id: Iad831899986baace6962f4b335eeb288250a1e22
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
Also ensure that dlopen(3) errors always include the name of the library we
failed to open.
Also fix a bug where we'd fall back to searching LD_LIBRARY_PATH and the
built-in paths for names that include slashes.
Bug: http://code.google.com/p/android/issues/detail?id=38479
Change-Id: Ib2c009ed083344a7a012749d58f8679db2f26c78
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
I gave up trying to use the usual thread-local buffer idiom; calls to
calloc(3) and free(3) from any of the "dl" functions -- which live in
the dynamic linker -- end up resolving to the dynamic linker's stubs.
I tried to work around that, but was just making things more complicated.
This alternative costs us a well-known TLS slot (instead of the
dynamically-allocated TLS slot we'd have used otherwise, so no difference
there), plus an extra buffer inside every pthread_internal_t.
Bug: 5404023
Change-Id: Ie9614edd05b6d1eeaf7bf9172792d616c6361767
Add unit tests for dlerror(3) in various situations. I think We're at least
as good as glibc now.
Also factor out the ScopedPthreadMutexLock and use it here too.
Bug: http://code.google.com/p/android/issues/detail?id=38398
Change-Id: I040938b4366ab836e3df46d1d8055b92f4ea6ed8
Currently, linker doesn't update the map->l_addr for execution.
Which could break the Unwind_Backtrace with PT_GNU_EH_FRAME enabled
in new toolchain.
Change-Id: Ifbd853134da64a962f7e4c4105e56a3f20def1b2
Author: Fengwei Yin <fengwei.yin@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Author-tracking-BZ: 57077
Lose the pid, only show the name of the function (not its whole signature),
and include the name of the library we failed to load. (I hadn't noticed
that the library name was missing before because in Java we add that into
the UnsatisfiedLinkError detail message.)
The new output looks like this:
Cannot load library: soinfo_relocate(linker.cpp:968): cannot locate symbol "__libc_malloc_default_dispatch" referenced by "libc_malloc_debug_leak.so"...
Change-Id: I3bb5c9780d9aaf3a9e4418ea55bc98122a81f80f
Per http://infocenter.arm.com/help/topic/com.arm.doc.ihi0044d/IHI0044D_aaelf.pdf
Section 4.7.1.10, ARM_R_COPY relocations are only suppose to reference shared
libraries, not the executable itself. When resolving an R_ARM_COPY symbol,
ensure we don't look in our own symbol.
This partially addresses
http://code.google.com/p/android/issues/detail?id=28598 . After this
patch, the printfs generated by the test program are:
global = 0x42 (0x401c7000)
global = 0x42 (0x11000)
before, the output was:
global = 0x42 (0x40071000)
global = 0x0 (0x11000)
I'm still not very happy with this patch, but I think it's an improvement
over where we were at before.
This change was modeled after https://android-review.googlesource.com/38871
Change-Id: Id7ad921e58395e76a36875bcc742ec5eeba53f08
This patch removes the DT_NEEDED hack which stores pointers
to soinfo structs in the .dynamic section of the library
being loaded.
Instead, it caches the soinfo struct pointers on the stack
during relocation time. After relocation time, i.e. when
calling constructors and destructors of the shared library
and its dependencies, uncached access is used instead,
doing lookups using the string table entries pointed to by
the DT_NEEDED entries.
By removing this hack, it is no longer needed to undo the
PT_GNURELRO protection, i.e., all non-writable mappings
can remain non-writable during their entire lifespan.
Even though, strictly speaking, the algorithmic complexity
has increased somewhat, the real-world adverse effect
is negligible on the systems I have tested.
Change-Id: I2361502560b96b5878f7f94a8e8a215350d70d64
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@gmail.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
Otherwise gdb will print a spurious warning each time gdb is used:
warning: .dynamic section for "/system/bin/linker" is not at the expected
address (wrong library or version mismatch?)
BUG:6946614
Change-Id: Ib21b8db0615751189c1601140deb43bc089289b6
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