From 4deaee41ce96e7666613ccffcc2499d6f2a8ae98 Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Fri, 21 Oct 2022 09:52:47 +0100 Subject: TODO(uapi): cheri: start: restrict auxv capability permissions TODO: not needed with full pcuabi --- elf/dl-support.c | 2 ++ elf/rtld.c | 2 ++ sysdeps/aarch64/morello/dl-machine.h | 2 ++ sysdeps/aarch64/morello/start.c | 2 ++ 4 files changed, 8 insertions(+) diff --git a/elf/dl-support.c b/elf/dl-support.c index ffc1d8d01b..f2f0bdbaf4 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -258,7 +258,9 @@ _dl_aux_init (ElfW(auxv_t) *av) # ifdef __CHERI_PURE_CAPABILITY__ _dl_main_map.l_map_start = auxv_values[AT_CHERI_EXEC_RX_CAP]; + _dl_main_map.l_map_start = __builtin_cheri_perms_and (_dl_main_map.l_map_start, CAP_PERM_MASK_RX); _dl_main_map.l_rw_start = auxv_values[AT_CHERI_EXEC_RW_CAP]; + _dl_main_map.l_rw_start = __builtin_cheri_perms_and (_dl_main_map.l_rw_start, CAP_PERM_MASK_RW); # endif } #endif diff --git a/elf/rtld.c b/elf/rtld.c index 41ffb297e5..7eeb5c174b 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -1724,9 +1724,11 @@ dl_main (const ElfW(Phdr) *phdr, { case AT_CHERI_EXEC_RX_CAP: main_map->l_map_start = av->a_un.a_val; + main_map->l_map_start = __builtin_cheri_perms_and (main_map->l_map_start, CAP_PERM_MASK_RX); break; case AT_CHERI_EXEC_RW_CAP: main_map->l_rw_start = av->a_un.a_val; + main_map->l_rw_start = __builtin_cheri_perms_and (main_map->l_rw_start, CAP_PERM_MASK_RW); break; } #endif diff --git a/sysdeps/aarch64/morello/dl-machine.h b/sysdeps/aarch64/morello/dl-machine.h index 0f681b1925..7da7c5bfc0 100644 --- a/sysdeps/aarch64/morello/dl-machine.h +++ b/sysdeps/aarch64/morello/dl-machine.h @@ -152,6 +152,8 @@ elf_machine_rtld_base_setup (struct link_map *map, void *args) cap_rw = cap_exe_rw; ldso_base = cap_rx; /* Assume load segments start at vaddr 0. */ } + cap_rx = __builtin_cheri_perms_and (cap_rx, CAP_PERM_MASK_RX); + cap_rw = __builtin_cheri_perms_and (cap_rw, CAP_PERM_MASK_RW); map->l_addr = ldso_base; map->l_map_start = cap_rx; map->l_rw_start = cap_rw; diff --git a/sysdeps/aarch64/morello/start.c b/sysdeps/aarch64/morello/start.c index de7aeab4c9..5d413ae78e 100644 --- a/sysdeps/aarch64/morello/start.c +++ b/sysdeps/aarch64/morello/start.c @@ -124,9 +124,11 @@ get_caps (uintptr_t *cap_rx, uintptr_t *cap_rw, const uintptr_t *auxv) return; case AT_CHERI_EXEC_RX_CAP: *cap_rx = auxv[1]; + *cap_rx = __builtin_cheri_perms_and (*cap_rx, CAP_PERM_MASK_RX); break; case AT_CHERI_EXEC_RW_CAP: *cap_rw = auxv[1]; + *cap_rw = __builtin_cheri_perms_and (*cap_rw, CAP_PERM_MASK_RW); break; } auxv += 2; -- cgit 1.4.1