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Index: head/libexec/rtld-elf/powerpc/reloc.c
===================================================================
--- head/libexec/rtld-elf/powerpc/reloc.c
+++ head/libexec/rtld-elf/powerpc/reloc.c
@@ -166,82 +166,84 @@
reloc_nonplt_object(Obj_Entry *obj_rtld __unused, Obj_Entry *obj,
const Elf_Rela *rela, SymCache *cache, int flags, RtldLockState *lockstate)
{
- Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
- const Elf_Sym *def;
- const Obj_Entry *defobj;
- Elf_Addr tmp;
+ const Elf_Sym *def = NULL;
+ const Obj_Entry *defobj;
+ Elf_Addr *where, symval = 0;
+ /*
+ * First, resolve symbol for relocations which
+ * reference symbols.
+ */
switch (ELF_R_TYPE(rela->r_info)) {
- case R_PPC_NONE:
- break;
-
- case R_PPC_ADDR32: /* word32 S + A */
- case R_PPC_GLOB_DAT: /* word32 S + A */
+ case R_PPC_UADDR32: /* word32 S + A */
+ case R_PPC_ADDR32:
+ case R_PPC_GLOB_DAT: /* word32 S + A */
+ case R_PPC_DTPMOD32:
+ case R_PPC_TPREL32:
+ case R_PPC_DTPREL32:
def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
flags, cache, lockstate);
if (def == NULL) {
return (-1);
}
- tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
- rela->r_addend);
-
- /* Don't issue write if unnecessary; avoid COW page fault */
- if (*where != tmp) {
- *where = tmp;
- }
- break;
-
- case R_PPC_RELATIVE: /* word32 B + A */
- tmp = (Elf_Addr)(obj->relocbase + rela->r_addend);
-
- /* As above, don't issue write unnecessarily */
- if (*where != tmp) {
- *where = tmp;
- }
- break;
-
- case R_PPC_COPY:
/*
- * These are deferred until all other relocations
- * have been done. All we do here is make sure
- * that the COPY relocation is not in a shared
- * library. They are allowed only in executable
- * files.
+ * 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 (!obj->mainprog) {
- _rtld_error("%s: Unexpected R_COPY "
- " relocation in shared library",
- obj->path);
- return (-1);
+ if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_PPC_UADDR32:
+ case R_PPC_ADDR32:
+ case R_PPC_GLOB_DAT:
+ if ((flags & SYMLOOK_IFUNC) == 0) {
+ dbg("Non-PLT reference to IFUNC found!");
+ obj->non_plt_gnu_ifunc = true;
+ return (0);
+ }
+ 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)
+ return (0);
+ symval = (Elf_Addr)defobj->relocbase +
+ def->st_value;
}
break;
+ default:
+ if ((flags & SYMLOOK_IFUNC) != 0)
+ return (0);
+ }
+ where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
- case R_PPC_JMP_SLOT:
- /*
- * These will be handled by the plt/jmpslot routines
- */
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_PPC_NONE:
break;
-
+ case R_PPC_UADDR32:
+ case R_PPC_ADDR32:
+ case R_PPC_GLOB_DAT:
+ /* Don't issue write if unnecessary; avoid COW page fault */
+ if (*where != symval + rela->r_addend) {
+ *where = symval + rela->r_addend;
+ }
+ break;
case R_PPC_DTPMOD32:
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
-
- if (def == NULL)
- return (-1);
-
*where = (Elf_Addr) defobj->tlsindex;
-
break;
-
case R_PPC_TPREL32:
- def = find_symdef(ELF_R_SYM(rela->r_info), 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
@@ -262,27 +264,52 @@
*(Elf_Addr **)where = *where * sizeof(Elf_Addr)
+ (Elf_Addr *)(def->st_value + rela->r_addend
+ defobj->tlsoffset - TLS_TP_OFFSET - TLS_TCB_SIZE);
-
break;
-
case R_PPC_DTPREL32:
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
-
- if (def == NULL)
- return (-1);
-
*where += (Elf_Addr)(def->st_value + rela->r_addend
- TLS_DTV_OFFSET);
+ break;
+ case R_PPC_RELATIVE: /* word32 B + A */
+ symval = (Elf_Addr)(obj->relocbase + rela->r_addend);
+ /* As above, don't issue write unnecessarily */
+ if (*where != symval) {
+ *where = symval;
+ }
break;
-
+ case R_PPC_COPY:
+ /*
+ * These are deferred until all other relocations
+ * have been done. All we do here is make sure
+ * that the COPY relocation is not in a shared
+ * library. They are allowed only in executable
+ * files.
+ */
+ if (!obj->mainprog) {
+ _rtld_error("%s: Unexpected R_COPY "
+ " relocation in shared library",
+ obj->path);
+ return (-1);
+ }
+ break;
+ case R_PPC_IRELATIVE:
+ /*
+ * These will be handled by reloc_iresolve().
+ */
+ obj->irelative = true;
+ break;
+ case R_PPC_JMP_SLOT:
+ /*
+ * These will be handled by the plt/jmpslot routines
+ */
+ break;
+
default:
_rtld_error("%s: Unsupported relocation type %d"
" in non-PLT relocations\n", obj->path,
ELF_R_TYPE(rela->r_info));
return (-1);
- }
+ }
return (0);
}
@@ -300,10 +327,6 @@
SymCache *cache;
int r = -1;
- 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().
@@ -404,7 +427,6 @@
return (0);
}
-
/*
* Process the PLT relocations.
*/
@@ -420,6 +442,17 @@
relalim = (const Elf_Rela *)((const char *)obj->pltrela +
obj->pltrelasize);
for (rela = obj->pltrela; rela < relalim; rela++) {
+ if (ELF_R_TYPE(rela->r_info) == R_PPC_IRELATIVE) {
+ dbg("ABI violation - found IRELATIVE in the PLT.");
+ obj->irelative = true;
+ continue;
+ }
+
+ /*
+ * PowerPC(64) .rela.plt is composed of an array of
+ * R_PPC_JMP_SLOT relocations. Unlike other platforms,
+ * this is the ONLY relocation type that is valid here.
+ */
assert(ELF_R_TYPE(rela->r_info) == R_PPC_JMP_SLOT);
if (reloc_plt_object(obj, rela) < 0) {
@@ -438,7 +471,6 @@
return (0);
}
-
/*
* LD_BIND_NOW was set - force relocation for all jump slots
*/
@@ -455,6 +487,9 @@
relalim = (const Elf_Rela *)((const char *)obj->pltrela +
obj->pltrelasize);
for (rela = obj->pltrela; rela < relalim; rela++) {
+ /* This isn't actually a jump slot, ignore it. */
+ if (ELF_R_TYPE(rela->r_info) == R_PPC_IRELATIVE)
+ continue;
assert(ELF_R_TYPE(rela->r_info) == R_PPC_JMP_SLOT);
where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
@@ -466,15 +501,18 @@
target = (Elf_Addr)(defobj->relocbase + def->st_value);
-#if 0
- /* PG XXX */
- dbg("\"%s\" in \"%s\" --> %p in \"%s\"",
- defobj->strtab + def->st_name, basename(obj->path),
- (void *)target, basename(defobj->path));
-#endif
-
- reloc_jmpslot(where, target, defobj, obj,
- (const Elf_Rel *) rela);
+ if (def == &sym_zero) {
+ /* Zero undefined weak symbols */
+ *where = 0;
+ } else {
+ if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
+ /* LD_BIND_NOW, ifunc in shared lib.*/
+ obj->gnu_ifunc = true;
+ continue;
+ }
+ reloc_jmpslot(where, target, defobj, obj,
+ (const Elf_Rel *) rela);
+ }
}
obj->jmpslots_done = true;
@@ -484,9 +522,7 @@
/*
- * Update the value of a PLT jump slot. Branch directly to the target if
- * it is within +/- 32Mb, otherwise go indirectly via the pltcall
- * trampoline call and jump table.
+ * Update the value of a PLT jump slot.
*/
Elf_Addr
reloc_jmpslot(Elf_Addr *wherep, Elf_Addr target,
@@ -501,22 +537,32 @@
if (ld_bind_not)
goto out;
+
/*
- * At the PLT entry pointed at by `wherep', construct
- * a direct transfer to the now fully resolved function
- * address.
+ * Process Secure-PLT.
*/
- offset = target - (Elf_Addr)wherep;
-
if (obj->gotptr != NULL) {
assert(wherep >= (Elf_Word *)obj->pltgot);
assert(wherep <
(Elf_Word *)obj->pltgot + obj->pltrelasize);
- *wherep = target;
+ if (*wherep != target)
+ *wherep = target;
goto out;
}
+ /*
+ * BSS-PLT optimization:
+ * Branch directly to the target if it is within +/- 32Mb,
+ * otherwise go indirectly via the pltcall trampoline call and
+ * jump table.
+ */
+ offset = target - (Elf_Addr)wherep;
if (abs((int)offset) < 32*1024*1024) { /* inside 32MB? */
+ /*
+ * At the PLT entry pointed at by `wherep', construct
+ * a direct transfer to the now fully resolved function
+ * address.
+ */
/* b value # branch directly */
*wherep = 0x48000000 | (offset & 0x03fffffc);
__syncicache(wherep, 4);
@@ -557,11 +603,52 @@
}
int
-reloc_iresolve(Obj_Entry *obj __unused,
- struct Struct_RtldLockState *lockstate __unused)
+reloc_iresolve(Obj_Entry *obj,
+ struct Struct_RtldLockState *lockstate)
{
+ /*
+ * Since PLT slots on PowerPC are always R_PPC_JMP_SLOT,
+ * R_PPC_IRELATIVE is in RELA.
+ */
+ 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 *)((const char *)obj->rela + obj->relasize);
+ for (rela = obj->rela; rela < relalim; rela++) {
+ if (ELF_R_TYPE(rela->r_info) == R_PPC_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;
+ }
+ }
+ /*
+ * XXX Remove me when lld is fixed!
+ * LLD currently makes illegal relocations in the PLT.
+ */
+ relalim = (const Elf_Rela *)((const char *)obj->pltrela + obj->pltrelasize);
+ for (rela = obj->pltrela; rela < relalim; rela++) {
+ if (ELF_R_TYPE(rela->r_info) == R_PPC_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);
}
@@ -569,8 +656,32 @@
reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused,
struct Struct_RtldLockState *lockstate __unused)
{
+ 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 *)((const char *)obj->pltrela + obj->pltrelasize);
+ for (rela = obj->pltrela; rela < relalim; rela++) {
+ if (ELF_R_TYPE(rela->r_info) == R_PPC_JMP_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);
}
@@ -662,6 +773,27 @@
* The icache will be sync'd in reloc_plt, which is called
* after all the slots have been updated
*/
+}
+
+/*
+ * 32 bit cpu feature flag fields.
+ */
+u_long cpu_features;
+u_long cpu_features2;
+
+void
+powerpc_abi_variant_hook(Elf_Auxinfo** aux_info)
+{
+ /*
+ * Since aux_info[] is easier to work with than aux, go ahead and
+ * initialize cpu_features / cpu_features2.
+ */
+ cpu_features = -1UL;
+ cpu_features2 = -1UL;
+ if (aux_info[AT_HWCAP] != NULL)
+ cpu_features = aux_info[AT_HWCAP]->a_un.a_val;
+ if (aux_info[AT_HWCAP2] != NULL)
+ cpu_features2 = aux_info[AT_HWCAP2]->a_un.a_val;
}
void
Index: head/libexec/rtld-elf/powerpc/rtld_machdep.h
===================================================================
--- head/libexec/rtld-elf/powerpc/rtld_machdep.h
+++ head/libexec/rtld-elf/powerpc/rtld_machdep.h
@@ -53,8 +53,13 @@
#define call_init_pointer(obj, target) \
(((InitArrFunc)(target))(main_argc, main_argv, environ))
+extern u_long cpu_features; /* r3 */
+extern u_long cpu_features2; /* r4 */
+/* r5-10: ifunc resolver parameters reserved for future assignment. */
#define call_ifunc_resolver(ptr) \
- (((Elf_Addr (*)(void))ptr)())
+ (((Elf_Addr (*)(uint32_t, uint32_t, uint32_t, uint32_t, uint32_t, \
+ uint32_t, uint32_t, uint32_t))ptr)((uint32_t)cpu_features, \
+ (uint32_t)cpu_features2, 0, 0, 0, 0, 0, 0))
/*
* PLT functions. Not really correct prototypes, but the
@@ -91,6 +96,7 @@
#define RTLD_DEFAULT_STACK_PF_EXEC PF_X
#define RTLD_DEFAULT_STACK_EXEC PROT_EXEC
-#define md_abi_variant_hook(x)
+extern void powerpc_abi_variant_hook(Elf_Auxinfo **);
+#define md_abi_variant_hook(x) powerpc_abi_variant_hook(x)
#endif

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