The Linux kernel provides an AT_SECURE auxv flag to inform userspace
whether or not a security transition has occurred. This is more reliable
than directly checking the uid/gid against the euid/egid, because it covers
not only setuid/setgid but also file capabilities, SELinux, and AppArmor
security transitions. It is also a more efficient test since it does
not require any additional system calls.
Change-Id: I9752a4f6da452273258d2876d13b05e402fb0409
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
android linker doesn't check machine type, it may load some
libraries which it doesn't support sometimes.
Author: Zhenghua Wang <zhenghua.wang@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
The computation of si->base assumed that the first entry in the
program header table is a PT_PHDR. This results in the dynamic
linker crashing with a SIGSEGV/MAPERR when trying to load some
of the NDK unit test programs, which happen to have an EXIDX
header first, followed byu a PHDR one.
This patch fixes the computation by parsing the program header
table, looking explicitely for the PHDR entry. This fixes the
load of the NDK unit test programs, and doesn't affect system
libraries.
Change-Id: Id18ea6037dbe950b5abbbce816c2960321f0b81d
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
Use LOCAL_NO_CRT to prevent linking against crtbegin.o, rather than
messing with build rules. This also prevents linking against crtend.o,
which isn't needed for the linker.
Change-Id: I0c5b9999be7e8676560fe145c1c033ffce8db4d1
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
Modify the dynamic linker so that executables can be loaded
at locations other than 0x00000000.
Modify crtbegin* so that non-PIC compilant "thumb interwork
veneers" are not created by the linker.
Bug: 5323301
Change-Id: Iece0272e2b708c79034f302c20160e1fe9029588
In 48527c3f74, we modified the soinfo
structure to remove an unnecessary variable. However, third party
programs seem to be relying on the structure not changing.
Add a dummy variable back into place to preserve structure.
Bug: 5064106
Change-Id: I3014dda1a46e624644b09e156c3e9381ba3729bd
This patch allows the debugging of constructors in shared
libraries and executables. It does so by ensuring that the
corresponding binary is visible to gdb before running the
constructors.
Change-Id: I0a3df726a04ad109944c834dcbba672b85d3991e
When a fatal signal is received, we now write a message to the log
that looks like this:
F/libc ( 1540): Fatal signal 11 (SIGSEGV) at 0xdeadd00d (code=1)
This is useful for debugging fatal signals that turn out not to be
fatal. This also changes the signal reset from SIG_IGN to SIG_DFL,
so that future non-fatal fatal signals are fatal.
The code that blocked SIGUSR1 to avoid being interrupted by the GC
has been removed.
Also, fix minor issues in format_buffer().
Bug 5035703
Change-Id: I8940af47297b5dcf3cf33537e3483ca5334ed565
Currently, the Android linker is placing shared libraries into
a well-known spot in memory. This is interfering with the kernel's
ASLR support.
This change stops forcing non-prelinked libraries into a particular
address space.
Also, get rid of FLAG_PRELINKED. As best I can tell, this flag
is never used.
Change-Id: I527af12fb54f821c2b5ca7693dbf63d022f8f4ae
Prelinked libraries must be mapped to a fixed address. MAP_FIXED is ignored
for non-prelinked libraries (si->base==0)
Signed-off-by: Raghu Gandham <raghu@mips.com>
* commit '962dcb22218a1a6d4ebd05e4fc4a69875d037234':
libc: Fix PTHREAD_RWLOCK_INITIALIZER
Proxy getnameinfo through netd
Updated gcc 4.4.3 IA toolchain doesn't require the .ctors list
Convert cname lenght before use
system_server loads up 87 shared libraries upon start. Running under
valgrind pushes this just over the edge of 96. Increase SO_MAX to 128 to
give us some more headroom.
Change-Id: Iadceb14ab6d9621bdccd292570d50867828057d9
The linker_env_get() method that is used to match an environment
variable was failing due to an incorrect equality check.
This was introduced in git change
be5755969d.
The bug was causing the linker to ignore environment variables such
as LD_LIBRARY_PATH. This issue also affects the linker_env_secure()
path that removes unsafe environment variables, since it would
not match any in the unsecure variable list.
Change-Id: I14228df9252010e9fb4c1862bed5735f23e97aec
The linker_env_get() method that is used to match an environment
variable was failing due to an incorrect equality check.
This was introduced in git change
be5755969d.
The bug was causing the linker to ignore environment variables such
as LD_LIBRARY_PATH. This issue also affects the linker_env_secure()
path that removes unsafe environment variables, since it would
not match any in the unsecure variable list.
Change-Id: I169024de4a005321e768accd38246fc1d717271b
This removes several unsecure environment variables from the
environment block when the program being loaded is setuid. The
list of env. variables is the same than what GLibc uses at this
point.
Change-Id: I456d3ea0880fe0d4de0d3c5dd51871dd36e87fd6
The LD_PRELOAD environment variable allows the user to specify a list of
libraries which should be unconditionally loaded before any others. This
makes possible some useful tricks, such as library interposers.
Change-Id: I433d775ab08ef63a5fbe7b21f87a5642954fc32f
The previous implementation of this flag was broken--it behaved identically
to RTLD_DEFAULT. This adds a proper implementation, which examines the address
of the calling function, and uses it to determine which library to use to begin
the symbol search process.
Change-Id: I2ad2b46363f68932af63a3828a22f9c7987eea67
