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 --- malloc/tst-interpose-aux.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'malloc') diff --git a/malloc/tst-interpose-aux.c b/malloc/tst-interpose-aux.c index 52696e92d3..a0ab2e5903 100644 --- a/malloc/tst-interpose-aux.c +++ b/malloc/tst-interpose-aux.c @@ -28,6 +28,7 @@ #include #include #include +#include #if INTERPOSE_THREADS #include @@ -96,6 +97,7 @@ struct __attribute__ ((aligned (__alignof__ (max_align_t)))) allocation_header { size_t allocation_index; size_t allocation_size; + struct timespec ts; }; /* Array of known allocations, to track invalid frees. */ @@ -166,6 +168,9 @@ malloc_internal (size_t size) .allocation_index = index, .allocation_size = allocation_size }; + /* BZ#24967: Check if calling a symbol which may use the vDSO does not fail. + The CLOCK_REALTIME should be supported on all systems. */ + clock_gettime (CLOCK_REALTIME, &allocations[index]->ts); return allocations[index] + 1; } -- cgit 1.4.1