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Index: head/libexec/rtld-elf/aarch64/reloc.c
===================================================================
--- head/libexec/rtld-elf/aarch64/reloc.c
+++ head/libexec/rtld-elf/aarch64/reloc.c
@@ -218,6 +218,9 @@
case R_AARCH64_TLSDESC:
reloc_tlsdesc(obj, rela, where);
break;
+ case R_AARCH64_IRELATIVE:
+ obj->irelative = true;
+ break;
default:
_rtld_error("Unknown relocation type %u in PLT",
(unsigned int)ELF_R_TYPE(rela->r_info));
@@ -242,19 +245,22 @@
relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
for (rela = obj->pltrela; rela < relalim; rela++) {
- Elf_Addr *where;
+ Elf_Addr *where, target;
where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
switch(ELF_R_TYPE(rela->r_info)) {
case R_AARCH64_JUMP_SLOT:
def = find_symdef(ELF_R_SYM(rela->r_info), obj,
&defobj, SYMLOOK_IN_PLT | flags, NULL, lockstate);
- if (def == NULL) {
- dbg("reloc_jmpslots: sym not found");
+ if (def == NULL)
return (-1);
+ if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
+ obj->gnu_ifunc = true;
+ continue;
}
-
- *where = (Elf_Addr)(defobj->relocbase + def->st_value);
+ target = (Elf_Addr)(defobj->relocbase + def->st_value);
+ reloc_jmpslot(where, target, defobj, obj,
+ (const Elf_Rel *)rela);
break;
case R_AARCH64_TLSDESC:
if (ELF_R_SYM(rela->r_info) != 0) {
@@ -277,8 +283,24 @@
int
reloc_iresolve(Obj_Entry *obj, struct Struct_RtldLockState *lockstate)
{
+ const Elf_Rela *relalim;
+ const Elf_Rela *rela;
+ Elf_Addr *where, target, *ptr;
- /* XXX not implemented */
+ if (!obj->irelative)
+ return (0);
+ relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
+ for (rela = obj->pltrela; rela < relalim; rela++) {
+ if (ELF_R_TYPE(rela->r_info) == R_AARCH64_IRELATIVE) {
+ ptr = (Elf_Addr *)(obj->relocbase + rela->r_addend);
+ where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
+ lock_release(rtld_bind_lock, lockstate);
+ target = call_ifunc_resolver(ptr);
+ wlock_acquire(rtld_bind_lock, lockstate);
+ *where = target;
+ }
+ }
+ obj->irelative = false;
return (0);
}
@@ -286,8 +308,32 @@
reloc_gnu_ifunc(Obj_Entry *obj, int flags,
struct Struct_RtldLockState *lockstate)
{
+ const Elf_Rela *relalim;
+ const Elf_Rela *rela;
+ Elf_Addr *where, target;
+ const Elf_Sym *def;
+ const Obj_Entry *defobj;
- /* XXX not implemented */
+ if (!obj->gnu_ifunc)
+ return (0);
+ relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
+ for (rela = obj->pltrela; rela < relalim; rela++) {
+ if (ELF_R_TYPE(rela->r_info) == R_AARCH64_JUMP_SLOT) {
+ where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
+ def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
+ SYMLOOK_IN_PLT | flags, NULL, lockstate);
+ if (def == NULL)
+ return (-1);
+ if (ELF_ST_TYPE(def->st_info) != STT_GNU_IFUNC)
+ continue;
+ lock_release(rtld_bind_lock, lockstate);
+ target = (Elf_Addr)rtld_resolve_ifunc(defobj, def);
+ wlock_acquire(rtld_bind_lock, lockstate);
+ reloc_jmpslot(where, target, defobj, obj,
+ (const Elf_Rel *)rela);
+ }
+ }
+ obj->gnu_ifunc = false;
return (0);
}
@@ -296,7 +342,8 @@
const Obj_Entry *obj, const Elf_Rel *rel)
{
- assert(ELF_R_TYPE(rel->r_info) == R_AARCH64_JUMP_SLOT);
+ assert(ELF_R_TYPE(rel->r_info) == R_AARCH64_JUMP_SLOT ||
+ ELF_R_TYPE(rel->r_info) == R_AARCH64_IRELATIVE);
if (*where != target && !ld_bind_not)
*where = target;
@@ -327,13 +374,8 @@
const Elf_Rela *rela;
const Elf_Sym *def;
SymCache *cache;
- Elf_Addr *where;
- unsigned long symnum;
+ Elf_Addr *where, symval;
- if ((flags & SYMLOOK_IFUNC) != 0)
- /* XXX not implemented */
- return (0);
-
/*
* The dynamic loader may be called from a thread, we have
* limited amounts of stack available so we cannot use alloca().
@@ -346,19 +388,62 @@
relalim = (const Elf_Rela *)((caddr_t)obj->rela + obj->relasize);
for (rela = obj->rela; rela < relalim; rela++) {
- where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
- symnum = ELF_R_SYM(rela->r_info);
-
+ /*
+ * First, resolve symbol for relocations which
+ * reference symbols.
+ */
switch (ELF_R_TYPE(rela->r_info)) {
case R_AARCH64_ABS64:
case R_AARCH64_GLOB_DAT:
- def = find_symdef(symnum, obj, &defobj, flags, cache,
- lockstate);
+ case R_AARCH64_TLS_TPREL64:
+ def = find_symdef(ELF_R_SYM(rela->r_info), obj,
+ &defobj, flags, cache, lockstate);
if (def == NULL)
return (-1);
+ /*
+ * If symbol is IFUNC, only perform relocation
+ * when caller allowed it by passing
+ * SYMLOOK_IFUNC flag. Skip the relocations
+ * otherwise.
+ *
+ * Also error out in case IFUNC relocations
+ * are specified for TLS, which cannot be
+ * usefully interpreted.
+ */
+ if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_AARCH64_ABS64:
+ case R_AARCH64_GLOB_DAT:
+ if ((flags & SYMLOOK_IFUNC) == 0) {
+ obj->non_plt_gnu_ifunc = true;
+ continue;
+ }
+ symval = (Elf_Addr)rtld_resolve_ifunc(
+ defobj, def);
+ break;
+ default:
+ _rtld_error("%s: IFUNC for TLS reloc",
+ obj->path);
+ return (-1);
+ }
+ } else {
+ if ((flags & SYMLOOK_IFUNC) != 0)
+ continue;
+ symval = (Elf_Addr)defobj->relocbase +
+ def->st_value;
+ }
+ break;
+ default:
+ if ((flags & SYMLOOK_IFUNC) != 0)
+ continue;
+ }
- *where = (Elf_Addr)defobj->relocbase + def->st_value +
- rela->r_addend;
+ where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
+
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_AARCH64_ABS64:
+ case R_AARCH64_GLOB_DAT:
+ *where = symval + rela->r_addend;
break;
case R_AARCH64_COPY:
/*
@@ -377,11 +462,6 @@
reloc_tlsdesc(obj, rela, where);
break;
case R_AARCH64_TLS_TPREL64:
- def = find_symdef(symnum, obj, &defobj, flags, cache,
- lockstate);
- if (def == NULL)
- return (-1);
-
/*
* We lazily allocate offsets for static TLS as we
* see the first relocation that references the
Index: head/libexec/rtld-elf/aarch64/rtld_machdep.h
===================================================================
--- head/libexec/rtld-elf/aarch64/rtld_machdep.h
+++ head/libexec/rtld-elf/aarch64/rtld_machdep.h
@@ -59,8 +59,16 @@
#define call_init_pointer(obj, target) \
(((InitArrFunc)(target))(main_argc, main_argv, environ))
+/*
+ * Pass zeros into the ifunc resolver so we can change them later. The first
+ * 8 arguments on arm64 are passed in registers so make them known values
+ * if we decide to use them later. Because of this ifunc resolvers can assume
+ * no arguments are passeed in, and if this changes later will be able to
+ * compare the argument with 0 to see if it is set.
+ */
#define call_ifunc_resolver(ptr) \
- (((Elf_Addr (*)(void))ptr)())
+ (((Elf_Addr (*)(uint64_t, uint64_t, uint64_t, uint64_t, uint64_t, \
+ uint64_t, uint64_t, uint64_t))ptr)(0, 0, 0, 0, 0, 0, 0, 0))
#define round(size, align) \
(((size) + (align) - 1) & ~((align) - 1))

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