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/riscv/flush-icache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'sysdeps/unix/sysv/linux/riscv/flush-icache.c') diff --git a/sysdeps/unix/sysv/linux/riscv/flush-icache.c b/sysdeps/unix/sysv/linux/riscv/flush-icache.c index f1565ab2dd..72caeb190f 100644 --- a/sysdeps/unix/sysv/linux/riscv/flush-icache.c +++ b/sysdeps/unix/sysv/linux/riscv/flush-icache.c @@ -39,7 +39,7 @@ __riscv_flush_icache_syscall (void *start, void *end, unsigned long int flags) static func_type __lookup_riscv_flush_icache (void) { - func_type func = get_vdso_symbol ("__vdso_flush_icache"); + func_type func = dl_vdso_vsym ("__vdso_flush_icache"); /* If there is no vDSO entry then call the system call directly. All Linux versions provide the vDSO entry, but QEMU's user-mode emulation doesn't -- cgit v1.2.3-70-g09d2