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| author | Szabolcs Nagy <szabolcs.nagy@arm.com> | 2022-08-30 16:00:57 +0100 |
|---|---|---|
| committer | Szabolcs Nagy <szabolcs.nagy@arm.com> | 2022-10-12 14:22:03 +0100 |
| commit | bb624b6c4376d3b3a3c4fe3ed5d1cd6366fd3ac6 (patch) | |
| tree | 68844ff5c47b52346e6ea1e18e44ea0ceb893eba | |
| parent | 8d2bab6e1795b5a2a6656a81e7419d6820a5d9cf (diff) | |
| download | glibc-bb624b6c4376d3b3a3c4fe3ed5d1cd6366fd3ac6.zip glibc-bb624b6c4376d3b3a3c4fe3ed5d1cd6366fd3ac6.tar.gz glibc-bb624b6c4376d3b3a3c4fe3ed5d1cd6366fd3ac6.tar.bz2 | |
aarch64: morello: use RW and RX capabilities for static start code
For each module there will be separate RW and RX capabilities that
cover the writable and all load segments respectively.
Prepare the relative reloc processing in static start code for such
separate capabilities.
| -rw-r--r-- | sysdeps/aarch64/morello/cheri-rel.h | 16 | ||||
| -rw-r--r-- | sysdeps/aarch64/morello/start.c | 9 |
2 files changed, 13 insertions, 12 deletions
diff --git a/sysdeps/aarch64/morello/cheri-rel.h b/sysdeps/aarch64/morello/cheri-rel.h index e5522ce..91271f4 100644 --- a/sysdeps/aarch64/morello/cheri-rel.h +++ b/sysdeps/aarch64/morello/cheri-rel.h @@ -3,9 +3,8 @@ #include <cheri_perms.h> static inline uintptr_t -morello_relative (uintptr_t base, - const ElfW(Rela) *reloc, - void *reloc_addr) +morello_relative (uint64_t base, uintptr_t cap_rx, uintptr_t cap_rw, + const ElfW(Rela) *reloc, void *reloc_addr) { uint64_t *__attribute__((may_alias)) u64_reloc_addr = reloc_addr; @@ -16,7 +15,12 @@ morello_relative (uintptr_t base, unsigned long perm = u64_reloc_addr[1] >> 56; uintptr_t value; - value = base + loc; + /* Permissions field is encoded as: + 4 = executable, 2 = read/write, 1 = read-only. */ + if (perm == 2) + value = __builtin_cheri_address_set (cap_rw, base + loc); + else + value = __builtin_cheri_address_set (cap_rx, base + loc); value = __builtin_cheri_bounds_set_exact (value, len); @@ -24,10 +28,6 @@ morello_relative (uintptr_t base, if (perm == 1) value = __builtin_cheri_perms_and (value, CAP_PERM_MASK_R); - if (perm == 2) - value = __builtin_cheri_perms_and (value, CAP_PERM_MASK_RW); - if (perm == 4) - value = __builtin_cheri_perms_and (value, CAP_PERM_MASK_RX); /* Seal executable capabilities with MORELLO_RB. */ if (perm == 4) diff --git a/sysdeps/aarch64/morello/start.c b/sysdeps/aarch64/morello/start.c index dda9adb..fbc9512 100644 --- a/sysdeps/aarch64/morello/start.c +++ b/sysdeps/aarch64/morello/start.c @@ -124,13 +124,14 @@ get_base (void) } static void -apply_rel (uintptr_t base, uintptr_t start, uintptr_t end) +apply_rel (uintptr_t cap_rx, uintptr_t cap_rw, uintptr_t start, uintptr_t end) { const ElfW(Rela) *r; for (r = (const ElfW(Rela) *)start; r != (void *)end; r++) { - uintptr_t *reloc_addr = base + r->r_offset; - uintptr_t value = morello_relative (base, r, reloc_addr); + uintptr_t *reloc_addr = + (uintptr_t *) __builtin_cheri_address_set (cap_rw, r->r_offset); + uintptr_t value = morello_relative (0, cap_rx, cap_rw, r, reloc_addr); *reloc_addr = value; } } @@ -151,7 +152,7 @@ __real_start (void rtld_fini (void), uintptr_t *sp) uintptr_t start = get_rela_dyn_start (); uintptr_t end = get_rela_dyn_end (); uintptr_t base = get_base (); - apply_rel (base, start, end); + apply_rel (base, base, start, end); rtld_fini = 0; } /* Compiler barrier after relocs are processed. */ |