From 1bdda52fe92fd01b424cd6fbb63e3df96a95015c Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Fri, 29 Nov 2019 10:44:59 -0300 Subject: 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 --- sysdeps/unix/sysv/linux/sysdep-vdso.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'sysdeps/unix/sysv/linux/sysdep-vdso.h') diff --git a/sysdeps/unix/sysv/linux/sysdep-vdso.h b/sysdeps/unix/sysv/linux/sysdep-vdso.h index f0cc384d78..dc6eaddbbf 100644 --- a/sysdeps/unix/sysv/linux/sysdep-vdso.h +++ b/sysdeps/unix/sysv/linux/sysdep-vdso.h @@ -19,8 +19,7 @@ #ifndef SYSDEP_VDSO_LINUX_H # define SYSDEP_VDSO_LINUX_H -#include -#include +#include #ifndef INTERNAL_VSYSCALL_CALL # define INTERNAL_VSYSCALL_CALL(funcptr, err, nr, args...) \ @@ -34,8 +33,7 @@ INTERNAL_SYSCALL_DECL (sc_err); \ long int sc_ret; \ \ - __typeof (__vdso_##name) vdsop = __vdso_##name; \ - PTR_DEMANGLE (vdsop); \ + __typeof (GLRO(dl_vdso_##name)) vdsop = GLRO(dl_vdso_##name); \ if (vdsop != NULL) \ { \ sc_ret = INTERNAL_VSYSCALL_CALL (vdsop, sc_err, nr, ##args); \ -- cgit v1.2.3-70-g09d2