glibc/sysdeps
Adhemerval Zanella 1bdda52fe9 elf: Move vDSO setup to rtld (BZ#24967)
This patch moves the vDSO setup from libc to loader code, just after
the vDSO link_map setup.  For static case the initialization
is moved to _dl_non_dynamic_init instead.

Instead of using the mangled pointer, the vDSO data is set as
attribute_relro (on _rtld_global_ro for shared or _dl_vdso_* for
static).  It is read-only even with partial relro.

It fixes BZ#24967 now that the vDSO pointer is setup earlier than
malloc interposition is called.

Also, vDSO calls should not be a problem for static dlopen as
indicated by BZ#20802.  The vDSO pointer would be zero-initialized
and the syscall will be issued instead.

Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu, s390x-linux-gnu, sparc64-linux-gnu, and
sparcv9-linux-gnu.  I also run some tests on mips.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2020-01-03 11:22:07 -03:00
..
aarch64 Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
alpha Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
arm Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
csky
generic elf: Move vDSO setup to rtld (BZ#24967) 2020-01-03 11:22:07 -03:00
gnu
hppa
htl
hurd
i386 Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
ia64 Linux: Use system call tables during build 2020-01-02 10:18:23 +01:00
ieee754 Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
init_array
m68k Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
mach
microblaze Linux: Use system call tables during build 2020-01-02 10:18:23 +01:00
mips Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
nios2
nptl
posix
powerpc elf: Move vDSO setup to rtld (BZ#24967) 2020-01-03 11:22:07 -03:00
pthread
riscv Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
s390 Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
sh
sparc Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
unix elf: Move vDSO setup to rtld (BZ#24967) 2020-01-03 11:22:07 -03:00
wordsize-32
wordsize-64
x86 Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00
x86_64 Add libm_alias_finite for _finite symbols 2020-01-03 10:02:04 -03:00