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-rw-r--r--libexec/rtld-elf/powerpc/reloc.c842
1 files changed, 842 insertions, 0 deletions
diff --git a/libexec/rtld-elf/powerpc/reloc.c b/libexec/rtld-elf/powerpc/reloc.c
new file mode 100644
index 000000000000..8932c2c21278
--- /dev/null
+++ b/libexec/rtld-elf/powerpc/reloc.c
@@ -0,0 +1,842 @@
+/* $NetBSD: ppc_reloc.c,v 1.10 2001/09/10 06:09:41 mycroft Exp $ */
+
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (C) 1998 Tsubai Masanari
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/param.h>
+#include <sys/mman.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <machine/cpu.h>
+#include <machine/atomic.h>
+#include <machine/md_var.h>
+
+#include "debug.h"
+#include "rtld.h"
+
+#define _ppc_ha(x) ((((u_int32_t)(x) & 0x8000) ? \
+ ((u_int32_t)(x) + 0x10000) : (u_int32_t)(x)) >> 16)
+#define _ppc_la(x) ((u_int32_t)(x) & 0xffff)
+
+#define min(a,b) (((a) < (b)) ? (a) : (b))
+#define max(a,b) (((a) > (b)) ? (a) : (b))
+
+#define PLT_EXTENDED_BEGIN (1 << 13)
+#define JMPTAB_BASE(N) (18 + N*2 + ((N > PLT_EXTENDED_BEGIN) ? \
+ (N - PLT_EXTENDED_BEGIN)*2 : 0))
+
+void _rtld_bind_secureplt_start(void);
+
+bool
+arch_digest_dynamic(struct Struct_Obj_Entry *obj, const Elf_Dyn *dynp)
+{
+ if (dynp->d_tag == DT_PPC_GOT) {
+ obj->gotptr = (Elf_Addr *)(obj->relocbase + dynp->d_un.d_ptr);
+ return (true);
+ }
+
+ return (false);
+}
+
+/*
+ * Process the R_PPC_COPY relocations
+ */
+int
+do_copy_relocations(Obj_Entry *dstobj)
+{
+ const Elf_Rela *relalim;
+ const Elf_Rela *rela;
+
+ /*
+ * COPY relocs are invalid outside of the main program
+ */
+ assert(dstobj->mainprog);
+
+ relalim = (const Elf_Rela *)((const char *) dstobj->rela +
+ dstobj->relasize);
+ for (rela = dstobj->rela; rela < relalim; rela++) {
+ void *dstaddr;
+ const Elf_Sym *dstsym;
+ const char *name;
+ size_t size;
+ const void *srcaddr;
+ const Elf_Sym *srcsym = NULL;
+ const Obj_Entry *srcobj, *defobj;
+ SymLook req;
+ int res;
+
+ if (ELF_R_TYPE(rela->r_info) != R_PPC_COPY) {
+ continue;
+ }
+
+ dstaddr = (void *)(dstobj->relocbase + rela->r_offset);
+ dstsym = dstobj->symtab + ELF_R_SYM(rela->r_info);
+ name = dstobj->strtab + dstsym->st_name;
+ size = dstsym->st_size;
+ symlook_init(&req, name);
+ req.ventry = fetch_ventry(dstobj, ELF_R_SYM(rela->r_info));
+ req.flags = SYMLOOK_EARLY;
+
+ for (srcobj = globallist_next(dstobj); srcobj != NULL;
+ srcobj = globallist_next(srcobj)) {
+ res = symlook_obj(&req, srcobj);
+ if (res == 0) {
+ srcsym = req.sym_out;
+ defobj = req.defobj_out;
+ break;
+ }
+ }
+
+ if (srcobj == NULL) {
+ _rtld_error("Undefined symbol \"%s\" "
+ " referenced from COPY"
+ " relocation in %s", name, dstobj->path);
+ return (-1);
+ }
+
+ srcaddr = (const void *)(defobj->relocbase+srcsym->st_value);
+ memcpy(dstaddr, srcaddr, size);
+ dbg("copy_reloc: src=%p,dst=%p,size=%d\n",srcaddr,dstaddr,size);
+ }
+
+ return (0);
+}
+
+
+/*
+ * Perform early relocation of the run-time linker image
+ */
+void
+reloc_non_plt_self(Elf_Dyn *dynp, Elf_Addr relocbase)
+{
+ const Elf_Rela *rela = NULL, *relalim;
+ Elf_Addr relasz = 0;
+ Elf_Addr *where;
+
+ /*
+ * Extract the rela/relasz values from the dynamic section
+ */
+ for (; dynp->d_tag != DT_NULL; dynp++) {
+ switch (dynp->d_tag) {
+ case DT_RELA:
+ rela = (const Elf_Rela *)(relocbase+dynp->d_un.d_ptr);
+ break;
+ case DT_RELASZ:
+ relasz = dynp->d_un.d_val;
+ break;
+ }
+ }
+
+ /*
+ * Relocate these values
+ */
+ relalim = (const Elf_Rela *)((const char *)rela + relasz);
+ for (; rela < relalim; rela++) {
+ where = (Elf_Addr *)(relocbase + rela->r_offset);
+ *where = (Elf_Addr)(relocbase + rela->r_addend);
+ }
+}
+
+
+/*
+ * Relocate a non-PLT object with addend.
+ */
+static int
+reloc_nonplt_object(Obj_Entry *obj_rtld __unused, Obj_Entry *obj,
+ const Elf_Rela *rela, SymCache *cache, int flags, RtldLockState *lockstate)
+{
+ 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_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);
+ }
+
+ /*
+ * 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_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);
+
+ 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:
+ *where = (Elf_Addr) defobj->tlsindex;
+ break;
+ case R_PPC_TPREL32:
+ /*
+ * We lazily allocate offsets for static TLS as we
+ * see the first relocation that references the
+ * TLS block. This allows us to support (small
+ * amounts of) static TLS in dynamically loaded
+ * modules. If we run out of space, we generate an
+ * error.
+ */
+ if (!defobj->tls_static) {
+ if (!allocate_tls_offset(
+ __DECONST(Obj_Entry *, defobj))) {
+ _rtld_error("%s: No space available for static "
+ "Thread Local Storage", obj->path);
+ return (-1);
+ }
+ }
+
+ *(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:
+ *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);
+}
+
+
+/*
+ * Process non-PLT relocations
+ */
+int
+reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags,
+ RtldLockState *lockstate)
+{
+ const Elf_Rela *relalim;
+ const Elf_Rela *rela;
+ const Elf_Phdr *phdr;
+ SymCache *cache;
+ int r = -1;
+
+ /*
+ * The dynamic loader may be called from a thread, we have
+ * limited amounts of stack available so we cannot use alloca().
+ */
+ if (obj != obj_rtld) {
+ cache = calloc(obj->dynsymcount, sizeof(SymCache));
+ /* No need to check for NULL here */
+ } else
+ cache = NULL;
+
+ /*
+ * From the SVR4 PPC ABI:
+ * "The PowerPC family uses only the Elf32_Rela relocation
+ * entries with explicit addends."
+ */
+ relalim = (const Elf_Rela *)((const char *)obj->rela + obj->relasize);
+ for (rela = obj->rela; rela < relalim; rela++) {
+ if (reloc_nonplt_object(obj_rtld, obj, rela, cache, flags,
+ lockstate) < 0)
+ goto done;
+ }
+ r = 0;
+done:
+ if (cache != NULL)
+ free(cache);
+
+ /*
+ * Synchronize icache for executable segments in case we made
+ * any changes.
+ */
+ for (phdr = obj->phdr;
+ (const char *)phdr < (const char *)obj->phdr + obj->phsize;
+ phdr++) {
+ if (phdr->p_type == PT_LOAD && (phdr->p_flags & PF_X) != 0) {
+ __syncicache(obj->relocbase + phdr->p_vaddr,
+ phdr->p_memsz);
+ }
+ }
+
+ return (r);
+}
+
+/*
+ * Initialise a PLT slot to the resolving trampoline
+ */
+static int
+reloc_plt_object(Obj_Entry *obj, const Elf_Rela *rela)
+{
+ Elf_Word *where = (Elf_Word *)(obj->relocbase + rela->r_offset);
+ Elf_Addr *pltresolve, *pltlongresolve, *jmptab;
+ Elf_Addr distance;
+ int N = obj->pltrelasize / sizeof(Elf_Rela);
+ int reloff;
+
+ reloff = rela - obj->pltrela;
+
+ if (reloff < 0)
+ return (-1);
+
+ if (obj->gotptr != NULL) {
+ *where += (Elf_Addr)obj->relocbase;
+ return (0);
+ }
+
+ pltlongresolve = obj->pltgot + 5;
+ pltresolve = pltlongresolve + 5;
+
+ distance = (Elf_Addr)pltresolve - (Elf_Addr)(where + 1);
+
+ dbg(" reloc_plt_object: where=%p,pltres=%p,reloff=%x,distance=%x",
+ (void *)where, (void *)pltresolve, reloff, distance);
+
+ if (reloff < PLT_EXTENDED_BEGIN) {
+ /* li r11,reloff */
+ /* b pltresolve */
+ where[0] = 0x39600000 | reloff;
+ where[1] = 0x48000000 | (distance & 0x03fffffc);
+ } else {
+ jmptab = obj->pltgot + JMPTAB_BASE(N);
+ jmptab[reloff] = (u_int)pltlongresolve;
+
+ /* lis r11,jmptab[reloff]@ha */
+ /* lwzu r12,jmptab[reloff]@l(r11) */
+ /* mtctr r12 */
+ /* bctr */
+ where[0] = 0x3d600000 | _ppc_ha(&jmptab[reloff]);
+ where[1] = 0x858b0000 | _ppc_la(&jmptab[reloff]);
+ where[2] = 0x7d8903a6;
+ where[3] = 0x4e800420;
+ }
+
+
+ /*
+ * The icache will be sync'd in reloc_plt, which is called
+ * after all the slots have been updated
+ */
+
+ return (0);
+}
+
+/*
+ * Process the PLT relocations.
+ */
+int
+reloc_plt(Obj_Entry *obj, int flags __unused, RtldLockState *lockstate __unused)
+{
+ const Elf_Rela *relalim;
+ const Elf_Rela *rela;
+ int N = obj->pltrelasize / sizeof(Elf_Rela);
+
+ if (obj->pltrelasize != 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_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) {
+ return (-1);
+ }
+ }
+ }
+
+ /*
+ * Sync the icache for the byte range represented by the
+ * trampoline routines and call slots.
+ */
+ if (obj->pltgot != NULL && obj->gotptr == NULL)
+ __syncicache(obj->pltgot, JMPTAB_BASE(N)*4);
+
+ return (0);
+}
+
+/*
+ * LD_BIND_NOW was set - force relocation for all jump slots
+ */
+int
+reloc_jmpslots(Obj_Entry *obj, int flags, RtldLockState *lockstate)
+{
+ const Obj_Entry *defobj;
+ const Elf_Rela *relalim;
+ const Elf_Rela *rela;
+ const Elf_Sym *def;
+ Elf_Addr *where;
+ Elf_Addr target;
+
+ 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,
+ SYMLOOK_IN_PLT | flags, NULL, lockstate);
+ if (def == NULL) {
+ dbg("reloc_jmpslots: sym not found");
+ return (-1);
+ }
+
+ target = (Elf_Addr)(defobj->relocbase + def->st_value);
+
+ 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;
+
+ return (0);
+}
+
+
+/*
+ * Update the value of a PLT jump slot.
+ */
+Elf_Addr
+reloc_jmpslot(Elf_Addr *wherep, Elf_Addr target,
+ const Obj_Entry *defobj __unused, const Obj_Entry *obj, const Elf_Rel *rel)
+{
+ Elf_Addr offset;
+ const Elf_Rela *rela = (const Elf_Rela *) rel;
+
+ dbg(" reloc_jmpslot: where=%p, target=%p",
+ (void *)wherep, (void *)target);
+
+ if (ld_bind_not)
+ goto out;
+
+
+ /*
+ * Process Secure-PLT.
+ */
+ if (obj->gotptr != NULL) {
+ assert(wherep >= (Elf_Word *)obj->pltgot);
+ assert(wherep <
+ (Elf_Word *)obj->pltgot + obj->pltrelasize);
+ 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);
+ } else {
+ Elf_Addr *pltcall, *jmptab;
+ int distance;
+ int N = obj->pltrelasize / sizeof(Elf_Rela);
+ int reloff = rela - obj->pltrela;
+
+ if (reloff < 0)
+ return (-1);
+
+ pltcall = obj->pltgot;
+
+ dbg(" reloc_jmpslot: indir, reloff=%x, N=%x\n",
+ reloff, N);
+
+ jmptab = obj->pltgot + JMPTAB_BASE(N);
+ jmptab[reloff] = target;
+ mb(); /* Order jmptab update before next changes */
+
+ if (reloff < PLT_EXTENDED_BEGIN) {
+ /* for extended PLT entries, we keep the old code */
+
+ distance = (Elf_Addr)pltcall - (Elf_Addr)(wherep + 1);
+
+ /* li r11,reloff */
+ /* b pltcall # use indirect pltcall routine */
+
+ /* first instruction same as before */
+ wherep[1] = 0x48000000 | (distance & 0x03fffffc);
+ __syncicache(wherep, 8);
+ }
+ }
+
+out:
+ return (target);
+}
+
+int
+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;
+
+ 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);
+}
+
+int
+reloc_iresolve_nonplt(Obj_Entry *obj __unused,
+ struct Struct_RtldLockState *lockstate __unused)
+{
+ return (0);
+}
+
+int
+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;
+
+ 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);
+}
+
+/*
+ * Setup the plt glue routines.
+ */
+#define PLTCALL_SIZE 20
+#define PLTLONGRESOLVE_SIZE 20
+#define PLTRESOLVE_SIZE 24
+
+void
+init_pltgot(Obj_Entry *obj)
+{
+ Elf_Word *pltcall, *pltresolve, *pltlongresolve;
+ Elf_Word *jmptab;
+ int N = obj->pltrelasize / sizeof(Elf_Rela);
+
+ pltcall = obj->pltgot;
+
+ if (pltcall == NULL) {
+ return;
+ }
+
+ /* Handle Secure-PLT first, if applicable. */
+ if (obj->gotptr != NULL) {
+ obj->gotptr[1] = (Elf_Addr)_rtld_bind_secureplt_start;
+ obj->gotptr[2] = (Elf_Addr)obj;
+ dbg("obj %s secure-plt gotptr=%p start=%p obj=%p",
+ obj->path, obj->gotptr,
+ (void *)obj->gotptr[1], (void *)obj->gotptr[2]);
+ return;
+ }
+
+ /*
+ * From the SVR4 PPC ABI:
+ *
+ * 'The first 18 words (72 bytes) of the PLT are reserved for
+ * use by the dynamic linker.
+ * ...
+ * 'If the executable or shared object requires N procedure
+ * linkage table entries, the link editor shall reserve 3*N
+ * words (12*N bytes) following the 18 reserved words. The
+ * first 2*N of these words are the procedure linkage table
+ * entries themselves. The static linker directs calls to bytes
+ * (72 + (i-1)*8), for i between 1 and N inclusive. The remaining
+ * N words (4*N bytes) are reserved for use by the dynamic linker.'
+ */
+
+ /*
+ * Copy the absolute-call assembler stub into the first part of
+ * the reserved PLT area.
+ */
+ memcpy(pltcall, _rtld_powerpc_pltcall, PLTCALL_SIZE);
+
+ /*
+ * Determine the address of the jumptable, which is the dyn-linker
+ * reserved area after the call cells. Write the absolute address
+ * of the jumptable into the absolute-call assembler code so it
+ * can determine this address.
+ */
+ jmptab = obj->pltgot + JMPTAB_BASE(N);
+ pltcall[1] |= _ppc_ha(jmptab); /* addis 11,11,jmptab@ha */
+ pltcall[2] |= _ppc_la(jmptab); /* lwz 11,jmptab@l(11) */
+
+ /*
+ * Skip down 20 bytes into the initial reserved area and copy
+ * in the standard resolving assembler call. Into this assembler,
+ * insert the absolute address of the _rtld_bind_start routine
+ * and the address of the relocation object.
+ *
+ * We place pltlongresolve first, so it can fix up its arguments
+ * and then fall through to the regular PLT resolver.
+ */
+ pltlongresolve = obj->pltgot + 5;
+
+ memcpy(pltlongresolve, _rtld_powerpc_pltlongresolve,
+ PLTLONGRESOLVE_SIZE);
+ pltlongresolve[0] |= _ppc_ha(jmptab); /* lis 12,jmptab@ha */
+ pltlongresolve[1] |= _ppc_la(jmptab); /* addi 12,12,jmptab@l */
+
+ pltresolve = pltlongresolve + PLTLONGRESOLVE_SIZE/sizeof(uint32_t);
+ memcpy(pltresolve, _rtld_powerpc_pltresolve, PLTRESOLVE_SIZE);
+ pltresolve[0] |= _ppc_ha(_rtld_bind_start);
+ pltresolve[1] |= _ppc_la(_rtld_bind_start);
+ pltresolve[3] |= _ppc_ha(obj);
+ pltresolve[4] |= _ppc_la(obj);
+
+ /*
+ * 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
+ifunc_init(Elf_Auxinfo *aux_info[__min_size(AT_COUNT)] __unused)
+{
+
+}
+
+void
+allocate_initial_tls(Obj_Entry *list)
+{
+
+ /*
+ * Fix the size of the static TLS block by using the maximum
+ * offset allocated so far and adding a bit for dynamic modules to
+ * use.
+ */
+
+ tls_static_space = tls_last_offset + tls_last_size +
+ ld_static_tls_extra;
+
+ _tcb_set(allocate_tls(list, NULL, TLS_TCB_SIZE, TLS_TCB_ALIGN));
+}
+
+void*
+__tls_get_addr(tls_index* ti)
+{
+ return (tls_get_addr_common(_tcb_get(), ti->ti_module, ti->ti_offset +
+ TLS_DTV_OFFSET));
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-08 10:34:07 +0000