From 13f3263aec09eeca6d77d15299b7f0fadac94f06 Mon Sep 17 00:00:00 2001 From: kib Date: Thu, 19 Jan 2017 06:48:03 +0000 Subject: [PATCH] MFC r311984: For the main binary, postpone enforcing relro read-only protection until copy relocations are done. git-svn-id: svn://svn.freebsd.org/base/stable/10@312402 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- libexec/rtld-elf/rtld.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c index f5b43dbfa..2ca08ef37 100644 --- a/libexec/rtld-elf/rtld.c +++ b/libexec/rtld-elf/rtld.c @@ -104,6 +104,7 @@ static int load_needed_objects(Obj_Entry *, int); static int load_preload_objects(void); static Obj_Entry *load_object(const char *, int fd, const Obj_Entry *, int); static void map_stacks_exec(RtldLockState *); +static int obj_enforce_relro(Obj_Entry *); static Obj_Entry *obj_from_addr(const void *); static void objlist_call_fini(Objlist *, Obj_Entry *, RtldLockState *); static void objlist_call_init(Objlist *, RtldLockState *); @@ -609,6 +610,10 @@ _rtld(Elf_Addr *sp, func_ptr_type *exit_proc, Obj_Entry **objp) if (do_copy_relocations(obj_main) == -1) rtld_die(); + dbg("enforcing main obj relro"); + if (obj_enforce_relro(obj_main) == -1) + rtld_die(); + if (getenv(LD_ "DUMP_REL_POST") != NULL) { dump_relocations(obj_main); exit (0); @@ -2691,14 +2696,8 @@ relocate_object(Obj_Entry *obj, bool bind_now, Obj_Entry *rtldobj, reloc_non_plt(obj, rtldobj, flags | SYMLOOK_IFUNC, lockstate)) return (-1); - if (obj->relro_size > 0) { - if (mprotect(obj->relro_page, obj->relro_size, - PROT_READ) == -1) { - _rtld_error("%s: Cannot enforce relro protection: %s", - obj->path, rtld_strerror(errno)); - return (-1); - } - } + if (!obj->mainprog && obj_enforce_relro(obj) == -1) + return (-1); /* * Set up the magic number and version in the Obj_Entry. These @@ -4986,6 +4985,19 @@ _rtld_is_dlopened(void *arg) return (res); } +int +obj_enforce_relro(Obj_Entry *obj) +{ + + if (obj->relro_size > 0 && mprotect(obj->relro_page, obj->relro_size, + PROT_READ) == -1) { + _rtld_error("%s: Cannot enforce relro protection: %s", + obj->path, rtld_strerror(errno)); + return (-1); + } + return (0); +} + static void map_stacks_exec(RtldLockState *lockstate) { -- 2.42.0