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/time.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'sysdeps/unix/sysv/linux/time.c') diff --git a/sysdeps/unix/sysv/linux/time.c b/sysdeps/unix/sysv/linux/time.c index 2dc4cbe786..9d8e573c0a 100644 --- a/sysdeps/unix/sysv/linux/time.c +++ b/sysdeps/unix/sysv/linux/time.c @@ -24,6 +24,7 @@ #ifdef SHARED # include +# include static time_t time_syscall (time_t *t) @@ -33,7 +34,7 @@ time_syscall (time_t *t) # undef INIT_ARCH # define INIT_ARCH() \ - void *vdso_time = get_vdso_symbol (HAVE_TIME_VSYSCALL); + void *vdso_time = dl_vdso_vsym (HAVE_TIME_VSYSCALL); libc_ifunc (time, vdso_time ? VDSO_IFUNC_RET (vdso_time) : (void *) time_syscall); -- cgit v1.2.3-70-g09d2