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
