/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. * Copyright (c) 1988 AT&T * All Rights Reserved * * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" #include #include #include #include #include #include "msg.h" #include "_libld.h" Word ld_init_rel(Rel_desc *reld, void *reloc) { Rel * rel = (Rel *)reloc; /* LINTED */ reld->rel_rtype = (Word)ELF_R_TYPE(rel->r_info); reld->rel_roffset = rel->r_offset; reld->rel_raddend = 0; reld->rel_typedata = 0; return ((Word)ELF_R_SYM(rel->r_info)); } void ld_mach_eflags(Ehdr *ehdr, Ofl_desc *ofl) { ofl->ofl_dehdr->e_flags |= ehdr->e_flags; } void ld_mach_make_dynamic(Ofl_desc *ofl, size_t *cnt) { if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) { /* * Create this entry if we are going to create a PLT table. */ if (ofl->ofl_pltcnt) (*cnt)++; /* DT_PLTGOT */ } } void ld_mach_update_odynamic(Ofl_desc *ofl, Dyn **dyn) { if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && ofl->ofl_pltcnt) { (*dyn)->d_tag = DT_PLTGOT; if (ofl->ofl_osgot) (*dyn)->d_un.d_ptr = ofl->ofl_osgot->os_shdr->sh_addr; else (*dyn)->d_un.d_ptr = 0; (*dyn)++; } } Xword ld_calc_plt_addr(Sym_desc *sdp, Ofl_desc *ofl) { Xword value; value = (Xword)(ofl->ofl_osplt->os_shdr->sh_addr) + M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE); return (value); } /* * Build a single plt entry - code is: * if (building a.out) * JMP *got_off * else * JMP *got_off@GOT(%ebx) * PUSHL &rel_off * JMP -n(%pc) # -n is pcrel offset to first plt entry * * The got_off@GOT entry gets filled with the address of the PUSHL, * so the first pass through the plt jumps back here, jumping * in turn to the first plt entry, which jumps to the dynamic * linker. The dynamic linker then patches the GOT, rerouting * future plt calls to the proper destination. */ static void plt_entry(Ofl_desc * ofl, Word rel_off, Sym_desc * sdp) { uchar_t *pltent, *gotent; Sword plt_off; Word got_off; got_off = sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; plt_off = M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE); pltent = (uchar_t *)(ofl->ofl_osplt->os_outdata->d_buf) + plt_off; gotent = (uchar_t *)(ofl->ofl_osgot->os_outdata->d_buf) + got_off; /* * Fill in the got entry with the address of the next instruction. */ /* LINTED */ *(Word *)gotent = ofl->ofl_osplt->os_shdr->sh_addr + plt_off + M_PLT_INSSIZE; if (!(ofl->ofl_flags & FLG_OF_SHAROBJ)) { pltent[0] = M_SPECIAL_INST; pltent[1] = M_JMP_DISP_IND; pltent += 2; /* LINTED */ *(Word *)pltent = (Word)(ofl->ofl_osgot->os_shdr->sh_addr + got_off); } else { pltent[0] = M_SPECIAL_INST; pltent[1] = M_JMP_REG_DISP_IND; pltent += 2; /* LINTED */ *(Word *)pltent = (Word)got_off; } pltent += 4; pltent[0] = M_INST_PUSHL; pltent++; /* LINTED */ *(Word *)pltent = (Word)rel_off; pltent += 4; plt_off = -(plt_off + 16); /* JMP, PUSHL, JMP take 16 bytes */ pltent[0] = M_INST_JMP; pltent++; /* LINTED */ *(Word *)pltent = (Word)plt_off; } uintptr_t ld_perform_outreloc(Rel_desc * orsp, Ofl_desc * ofl) { Os_desc * relosp, * osp = 0; Word ndx, roffset, value; Rel rea; char *relbits; Sym_desc * sdp, * psym = (Sym_desc *)0; int sectmoved = 0; sdp = orsp->rel_sym; /* * If the section this relocation is against has been discarded * (-zignore), then also discard (skip) the relocation itself. */ if (orsp->rel_isdesc && ((orsp->rel_flags & (FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0) && (orsp->rel_isdesc->is_flags & FLG_IS_DISCARD)) { DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, orsp)); return (1); } /* * If this is a relocation against a move table, or expanded move * table, adjust the relocation entries. */ if (orsp->rel_move) ld_adj_movereloc(ofl, orsp); /* * If this is a relocation against a section using a partial initialized * symbol, adjust the embedded symbol info. * * The second argument of the am_I_partial() is the value stored at the * target address relocation is going to be applied. */ if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { if (ofl->ofl_parsym.head && (sdp->sd_isc->is_flags & FLG_IS_RELUPD) && /* LINTED */ (psym = ld_am_I_partial(orsp, *(Xword *) ((uchar_t *)(orsp->rel_isdesc->is_indata->d_buf) + orsp->rel_roffset)))) { DBG_CALL(Dbg_move_outsctadj(ofl->ofl_lml, psym)); sectmoved = 1; } } value = sdp->sd_sym->st_value; if (orsp->rel_flags & FLG_REL_GOT) { osp = ofl->ofl_osgot; roffset = (Word)ld_calc_got_offset(orsp, ofl); } else if (orsp->rel_flags & FLG_REL_PLT) { /* * Note that relocations for PLT's actually * cause a relocation againt the GOT. */ osp = ofl->ofl_osplt; roffset = (Word) (ofl->ofl_osgot->os_shdr->sh_addr) + sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE; plt_entry(ofl, osp->os_relosdesc->os_szoutrels, sdp); } else if (orsp->rel_flags & FLG_REL_BSS) { /* * This must be a R_386_COPY. For these set the roffset to * point to the new symbols location. */ osp = ofl->ofl_isbss->is_osdesc; roffset = (Word)value; } else { osp = orsp->rel_osdesc; /* * Calculate virtual offset of reference point; equals offset * into section + vaddr of section for loadable sections, or * offset plus section displacement for nonloadable sections. */ roffset = orsp->rel_roffset + (Off)_elf_getxoff(orsp->rel_isdesc->is_indata); if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) roffset += orsp->rel_isdesc->is_osdesc-> os_shdr->sh_addr; } if ((osp == 0) || ((relosp = osp->os_relosdesc) == 0)) relosp = ofl->ofl_osrel; /* * Assign the symbols index for the output relocation. If the * relocation refers to a SECTION symbol then it's index is based upon * the output sections symbols index. Otherwise the index can be * derived from the symbols index itself. */ if (orsp->rel_rtype == R_386_RELATIVE) ndx = STN_UNDEF; else if ((orsp->rel_flags & FLG_REL_SCNNDX) || (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) { if (sectmoved == 0) { /* * Check for a null input section. This can * occur if this relocation references a symbol * generated by sym_add_sym(). */ if ((sdp->sd_isc != 0) && (sdp->sd_isc->is_osdesc != 0)) ndx = sdp->sd_isc->is_osdesc->os_scnsymndx; else ndx = sdp->sd_shndx; } else ndx = ofl->ofl_sunwdata1ndx; } else ndx = sdp->sd_symndx; relbits = (char *)relosp->os_outdata->d_buf; rea.r_info = ELF_R_INFO(ndx, orsp->rel_rtype); rea.r_offset = roffset; DBG_CALL(Dbg_reloc_out(ofl, ELF_DBG_LD, SHT_REL, &rea, relosp->os_name, orsp->rel_sname)); /* * Assert we haven't walked off the end of our relocation table. */ assert(relosp->os_szoutrels <= relosp->os_shdr->sh_size); (void) memcpy((relbits + relosp->os_szoutrels), (char *)&rea, sizeof (Rel)); relosp->os_szoutrels += sizeof (Rel); /* * Determine if this relocation is against a non-writable, allocatable * section. If so we may need to provide a text relocation diagnostic. * Note that relocations against the .plt (R_386_JMP_SLOT) actually * result in modifications to the .got. */ if (orsp->rel_rtype == R_386_JMP_SLOT) osp = ofl->ofl_osgot; ld_reloc_remain_entry(orsp, osp, ofl); return (1); } /* * i386 Instructions for TLS processing */ static uchar_t tlsinstr_gd_ie[] = { /* * 0x00 movl %gs:0x0, %eax */ 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, /* * 0x06 addl x(%eax), %eax * 0x0c ... */ 0x03, 0x80, 0x00, 0x00, 0x00, 0x00 }; static uchar_t tlsinstr_gd_le[] = { /* * 0x00 movl %gs:0x0, %eax */ 0x65, 0xa1, 0x00, 0x00, 0x00, 0x00, /* * 0x06 addl $0x0, %eax */ 0x05, 0x00, 0x00, 0x00, 0x00, /* * 0x0b nop * 0x0c */ 0x90 }; static uchar_t tlsinstr_gd_ie_movgs[] = { /* * movl %gs:0x0,%eax */ 0x65, 0xa1, 0x00, 0x00, 0x00, 00 }; #define TLS_GD_IE_MOV 0x8b /* movl opcode */ #define TLS_GD_IE_POP 0x58 /* popl + reg */ #define TLS_GD_LE_MOVL 0xb8 /* movl + reg */ #define TLS_NOP 0x90 /* NOP instruction */ #define MODRM_MSK_MOD 0xc0 #define MODRM_MSK_RO 0x38 #define MODRM_MSK_RM 0x07 #define SIB_MSK_SS 0xc0 #define SIB_MSK_IND 0x38 #define SIB_MSK_BS 0x07 static Fixupret tls_fixups(Ofl_desc *ofl, Rel_desc *arsp) { Sym_desc *sdp = arsp->rel_sym; Word rtype = arsp->rel_rtype; uchar_t *offset, r1, r2; offset = (uchar_t *)((uintptr_t)arsp->rel_roffset + (uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata) + (uintptr_t)arsp->rel_osdesc->os_outdata->d_buf); if (sdp->sd_ref == REF_DYN_NEED) { /* * IE reference model */ switch (rtype) { case R_386_TLS_GD: /* * Transition: * 0x0 leal x@tlsgd(,r1,1), %eax * 0x7 call ___tls_get_addr * 0xc * To: * 0x0 movl %gs:0, %eax * 0x6 addl x@gotntpoff(r1), %eax */ DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_TLS_GOTIE, arsp->rel_roffset, sdp->sd_name)); arsp->rel_rtype = R_386_TLS_GOTIE; arsp->rel_roffset += 5; /* * Addjust 'offset' to beginning of instruction * sequence. */ offset -= 3; r1 = (offset[2] & SIB_MSK_IND) >> 3; (void) memcpy(offset, tlsinstr_gd_ie, sizeof (tlsinstr_gd_ie)); /* * set register %r1 into the addl * instruction. */ offset[0x7] |= r1; return (FIX_RELOC); case R_386_TLS_GD_PLT: /* * Fixup done via the TLS_GD relocation */ DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_NONE, arsp->rel_roffset, sdp->sd_name)); return (FIX_DONE); } } /* * LE reference model */ switch (rtype) { case R_386_TLS_GD: /* * Transition: * 0x0 leal x@tlsgd(,r1,1), %eax * 0x7 call ___tls_get_addr * 0xc * To: * 0x0 movl %gs:0, %eax * 0x6 addl $x@ntpoff, %eax * 0xb nop * 0xc */ DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_TLS_LE, arsp->rel_roffset, sdp->sd_name)); arsp->rel_rtype = R_386_TLS_LE; arsp->rel_roffset += 4; /* * Addjust 'offset' to beginning of instruction * sequence. */ offset -= 3; (void) memcpy(offset, tlsinstr_gd_le, sizeof (tlsinstr_gd_le)); return (FIX_RELOC); case R_386_TLS_GD_PLT: case R_386_PLT32: /* * Fixup done via the TLS_GD relocation */ DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_NONE, arsp->rel_roffset, sdp->sd_name)); return (FIX_DONE); case R_386_TLS_LDM_PLT: DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_NONE, arsp->rel_roffset, sdp->sd_name)); /* * Transition: * call __tls_get_addr() * to: * nop * nop * nop * nop * nop */ *(offset - 1) = TLS_NOP; *(offset) = TLS_NOP; *(offset + 1) = TLS_NOP; *(offset + 2) = TLS_NOP; *(offset + 3) = TLS_NOP; return (FIX_DONE); case R_386_TLS_LDM: DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_NONE, arsp->rel_roffset, sdp->sd_name)); /* * Transition: * * 0x00 leal x1@tlsldm(%ebx), %eax * 0x06 call ___tls_get_addr * * to: * * 0x00 movl %gs:0, %eax */ (void) memcpy(offset - 2, tlsinstr_gd_ie_movgs, sizeof (tlsinstr_gd_ie_movgs)); return (FIX_DONE); case R_386_TLS_LDO_32: /* * Instructions: * * 0x10 leal x1@dtpoff(%eax), %edx R_386_TLS_LDO_32 * to * 0x10 leal x1@ntpoff(%eax), %edx R_386_TLS_LE * */ offset -= 2; DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_TLS_LE, arsp->rel_roffset, sdp->sd_name)); arsp->rel_rtype = R_386_TLS_LE; return (FIX_RELOC); case R_386_TLS_GOTIE: /* * These transitions are a little different than the * others, in that we could have multiple instructions * pointed to by a single relocation. Depending upon the * instruction, we perform a different code transition. * * Here's the known transitions: * * 1) movl foo@gotntpoff(%reg1), %reg2 * 0x8b, 0x80 | (reg2 << 3) | reg1, foo@gotntpoff * * 2) addl foo@gotntpoff(%reg1), %reg2 * 0x03, 0x80 | (reg2 << 3) | reg1, foo@gotntpoff * * Transitions IE -> LE * * 1) movl $foo@ntpoff, %reg2 * 0xc7, 0xc0 | reg2, foo@ntpoff * * 2) addl $foo@ntpoff, %reg2 * 0x81, 0xc0 | reg2, foo@ntpoff * * Note: reg1 != 4 (%esp) */ DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH, rtype, R_386_TLS_LE, arsp->rel_roffset, sdp->sd_name)); arsp->rel_rtype = R_386_TLS_LE; offset -= 2; r2 = (offset[1] & MODRM_MSK_RO) >> 3; if (offset[0] == 0x8b) { /* case 1 above */ offset[0] = 0xc7; /* movl */ offset[1] = 0xc0 | r2; return (FIX_RELOC); } if (offset[0] == 0x03) { /* case 2 above */ assert(offset[0] == 0x03); offset[0] = 0x81; /* addl */ offset[1] = 0xc0 | r2; return (FIX_RELOC); } /* * Unexpected instruction sequence - fatal error. */ eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS), conv_reloc_386_type(arsp->rel_rtype, 0), arsp->rel_isdesc->is_file->ifl_name, demangle(arsp->rel_sname), arsp->rel_isdesc->is_name, EC_OFF(arsp->rel_roffset)); return (FIX_ERROR); case R_386_TLS_IE: /* * These transitions are a little different than the * others, in that we could have multiple instructions * pointed to by a single relocation. Depending upon the * instruction, we perform a different code transition. * * Here's the known transitions: * 1) movl foo@indntpoff, %eax * 0xa1, foo@indntpoff * * 2) movl foo@indntpoff, %eax * 0x8b, 0x05 | (reg << 3), foo@gotntpoff * * 3) addl foo@indntpoff, %eax * 0x03, 0x05 | (reg << 3), foo@gotntpoff * * Transitions IE -> LE * * 1) movl $foo@ntpoff, %eax * 0xb8, foo@ntpoff * * 2) movl $foo@ntpoff, %reg * 0xc7, 0xc0 | reg, foo@ntpoff * * 3) addl $foo@ntpoff, %reg * 0x81, 0xc0 | reg, foo@ntpoff */ arsp->rel_rtype = R_386_TLS_LE; offset--; if (offset[0] == 0xa1) { /* case 1 above */ offset[0] = 0xb8; /* movl */ return (FIX_RELOC); } offset--; if (offset[0] == 0x8b) { /* case 2 above */ r2 = (offset[1] & MODRM_MSK_RO) >> 3; offset[0] = 0xc7; /* movl */ offset[1] = 0xc0 | r2; return (FIX_RELOC); } if (offset[0] == 0x03) { /* case 3 above */ r2 = (offset[1] & MODRM_MSK_RO) >> 3; offset[0] = 0x81; /* addl */ offset[1] = 0xc0 | r2; return (FIX_RELOC); } /* * Unexpected instruction sequence - fatal error. */ eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS), conv_reloc_386_type(arsp->rel_rtype, 0), arsp->rel_isdesc->is_file->ifl_name, demangle(arsp->rel_sname), arsp->rel_isdesc->is_name, EC_OFF(arsp->rel_roffset)); return (FIX_ERROR); } return (FIX_RELOC); } uintptr_t ld_do_activerelocs(Ofl_desc *ofl) { Rel_desc *arsp; Rel_cache *rcp; Listnode *lnp; uintptr_t return_code = 1; Word flags = ofl->ofl_flags; Word dtflags1 = ofl->ofl_dtflags_1; if (ofl->ofl_actrels.head) DBG_CALL(Dbg_reloc_doact_title(ofl->ofl_lml)); /* * Process active relocations. */ for (LIST_TRAVERSE(&ofl->ofl_actrels, lnp, rcp)) { /* LINTED */ for (arsp = (Rel_desc *)(rcp + 1); arsp < rcp->rc_free; arsp++) { uchar_t *addr; Xword value; Sym_desc *sdp; const char *ifl_name; Xword refaddr; int moved = 0; Gotref gref; /* * If the section this relocation is against has been * discarded (-zignore), then discard (skip) the * relocation itself. */ if ((arsp->rel_isdesc->is_flags & FLG_IS_DISCARD) && ((arsp->rel_flags & (FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0)) { DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, arsp)); continue; } /* * We deteremine what the 'got reference' * model (if required) is at this point. This * needs to be done before tls_fixup() since * it may 'transition' our instructions. * * The got table entries have already been assigned, * and we bind to those initial entries. */ if (arsp->rel_flags & FLG_REL_DTLS) gref = GOT_REF_TLSGD; else if (arsp->rel_flags & FLG_REL_MTLS) gref = GOT_REF_TLSLD; else if (arsp->rel_flags & FLG_REL_STLS) gref = GOT_REF_TLSIE; else gref = GOT_REF_GENERIC; /* * Perform any required TLS fixups. */ if (arsp->rel_flags & FLG_REL_TLSFIX) { Fixupret ret; if ((ret = tls_fixups(ofl, arsp)) == FIX_ERROR) return (S_ERROR); if (ret == FIX_DONE) continue; } /* * If this is a relocation against a move table, or * expanded move table, adjust the relocation entries. */ if (arsp->rel_move) ld_adj_movereloc(ofl, arsp); sdp = arsp->rel_sym; refaddr = arsp->rel_roffset + (Off)_elf_getxoff(arsp->rel_isdesc->is_indata); if (arsp->rel_flags & FLG_REL_CLVAL) value = 0; else if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) { Sym_desc *sym; /* * The value for a symbol pointing to a SECTION * is based off of that sections position. * * The second argument of the ld_am_I_partial() * is the value stored at the target address * relocation is going to be applied. */ if ((sdp->sd_isc->is_flags & FLG_IS_RELUPD) && /* LINTED */ (sym = ld_am_I_partial(arsp, *(Xword *) ((uchar_t *) arsp->rel_isdesc->is_indata->d_buf + arsp->rel_roffset)))) { /* * If the symbol is moved, * adjust the value */ value = sym->sd_sym->st_value; moved = 1; } else { value = _elf_getxoff( sdp->sd_isc->is_indata); if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC) value += sdp->sd_isc-> is_osdesc->os_shdr->sh_addr; } if (sdp->sd_isc->is_shdr->sh_flags & SHF_TLS) value -= ofl->ofl_tlsphdr->p_vaddr; } else { /* * Else the value is the symbols value. */ value = sdp->sd_sym->st_value; } /* * Relocation against the GLOBAL_OFFSET_TABLE. */ if (arsp->rel_flags & FLG_REL_GOT) arsp->rel_osdesc = ofl->ofl_osgot; /* * If loadable and not producing a relocatable object * add the sections virtual address to the reference * address. */ if ((arsp->rel_flags & FLG_REL_LOAD) && ((flags & FLG_OF_RELOBJ) == 0)) refaddr += arsp->rel_isdesc->is_osdesc-> os_shdr->sh_addr; /* * If this entry has a PLT assigned to it, it's * value is actually the address of the PLT (and * not the address of the function). */ if (IS_PLT(arsp->rel_rtype)) { if (sdp->sd_aux && sdp->sd_aux->sa_PLTndx) value = ld_calc_plt_addr(sdp, ofl); } /* * Determine whether the value needs further adjustment. * Filter through the attributes of the relocation to * determine what adjustment is required. Note, many * of the following cases are only applicable when a * .got is present. As a .got is not generated when a * relocatable object is being built, any adjustments * that require a .got need to be skipped. */ if ((arsp->rel_flags & FLG_REL_GOT) && ((flags & FLG_OF_RELOBJ) == 0)) { Xword R1addr; uintptr_t R2addr; Word gotndx; Gotndx *gnp; /* * Perform relocation against GOT table. Since * this doesn't fit exactly into a relocation * we place the appropriate byte in the GOT * directly * * Calculate offset into GOT at which to apply * the relocation. */ gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), gref, ofl, 0); assert(gnp); if (arsp->rel_rtype == R_386_TLS_DTPOFF32) gotndx = gnp->gn_gotndx + 1; else gotndx = gnp->gn_gotndx; R1addr = (Xword)(gotndx * M_GOT_ENTSIZE); /* * Add the GOTs data's offset. */ R2addr = R1addr + (uintptr_t) arsp->rel_osdesc->os_outdata->d_buf; DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD, M_MACH, SHT_REL, arsp->rel_rtype, R1addr, value, arsp->rel_sname, arsp->rel_osdesc)); /* * And do it. */ *(Xword *)R2addr = value; continue; } else if (IS_GOT_BASED(arsp->rel_rtype) && ((flags & FLG_OF_RELOBJ) == 0)) { value -= ofl->ofl_osgot->os_shdr->sh_addr; } else if (IS_GOT_PC(arsp->rel_rtype) && ((flags & FLG_OF_RELOBJ) == 0)) { value = (Xword)(ofl->ofl_osgot->os_shdr->sh_addr) - refaddr; } else if ((IS_PC_RELATIVE(arsp->rel_rtype)) && (((flags & FLG_OF_RELOBJ) == 0) || (arsp->rel_osdesc == sdp->sd_isc->is_osdesc))) { value -= refaddr; } else if (IS_TLS_INS(arsp->rel_rtype) && IS_GOT_RELATIVE(arsp->rel_rtype) && ((flags & FLG_OF_RELOBJ) == 0)) { Gotndx *gnp; gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), gref, ofl, 0); assert(gnp); value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; if (arsp->rel_rtype == R_386_TLS_IE) { value += ofl->ofl_osgot->os_shdr->sh_addr; } } else if (IS_GOT_RELATIVE(arsp->rel_rtype) && ((flags & FLG_OF_RELOBJ) == 0)) { Gotndx *gnp; gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), GOT_REF_GENERIC, ofl, 0); assert(gnp); value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE; } else if ((arsp->rel_flags & FLG_REL_STLS) && ((flags & FLG_OF_RELOBJ) == 0)) { Xword tlsstatsize; /* * This is the LE TLS reference model. Static * offset is hard-coded. */ tlsstatsize = S_ROUND(ofl->ofl_tlsphdr->p_memsz, M_TLSSTATALIGN); value = tlsstatsize - value; /* * Since this code is fixed up, it assumes a * negative offset that can be added to the * thread pointer. */ if ((arsp->rel_rtype == R_386_TLS_LDO_32) || (arsp->rel_rtype == R_386_TLS_LE)) value = -value; } if (arsp->rel_isdesc->is_file) ifl_name = arsp->rel_isdesc->is_file->ifl_name; else ifl_name = MSG_INTL(MSG_STR_NULL); /* * Make sure we have data to relocate. Compiler and * assembler developers have been known to generate * relocations against invalid sections (normally .bss), * so for their benefit give them sufficient information * to help analyze the problem. End users should never * see this. */ if (arsp->rel_isdesc->is_indata->d_buf == 0) { eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_EMPTYSEC), conv_reloc_386_type(arsp->rel_rtype, 0), ifl_name, demangle(arsp->rel_sname), arsp->rel_isdesc->is_name); return (S_ERROR); } /* * Get the address of the data item we need to modify. */ addr = (uchar_t *)((uintptr_t)arsp->rel_roffset + (uintptr_t)_elf_getxoff(arsp->rel_isdesc-> is_indata)); DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD, M_MACH, SHT_REL, arsp->rel_rtype, EC_NATPTR(addr), value, arsp->rel_sname, arsp->rel_osdesc)); addr += (uintptr_t)arsp->rel_osdesc->os_outdata->d_buf; if ((((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > ofl->ofl_size) || (arsp->rel_roffset > arsp->rel_osdesc->os_shdr->sh_size)) { int class; if (((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) > ofl->ofl_size) class = ERR_FATAL; else class = ERR_WARNING; eprintf(ofl->ofl_lml, class, MSG_INTL(MSG_REL_INVALOFFSET), conv_reloc_386_type(arsp->rel_rtype, 0), ifl_name, arsp->rel_isdesc->is_name, demangle(arsp->rel_sname), EC_ADDR((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr)); if (class == ERR_FATAL) { return_code = S_ERROR; continue; } } /* * The relocation is additive. Ignore the previous * symbol value if this local partial symbol is * expanded. */ if (moved) value -= *addr; /* * If '-z noreloc' is specified - skip the do_reloc * stage. */ if ((flags & FLG_OF_RELOBJ) || !(dtflags1 & DF_1_NORELOC)) { if (do_reloc((uchar_t)arsp->rel_rtype, addr, &value, arsp->rel_sname, ifl_name, ofl->ofl_lml) == 0) return_code = S_ERROR; } } } return (return_code); } /* * Add an output relocation record. */ uintptr_t ld_add_outrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl) { Rel_desc *orsp; Rel_cache *rcp; Sym_desc *sdp = rsp->rel_sym; /* * Static executables *do not* want any relocations against them. * Since our engine still creates relocations against a WEAK UNDEFINED * symbol in a static executable, it's best to disable them here * instead of through out the relocation code. */ if ((ofl->ofl_flags & (FLG_OF_STATIC | FLG_OF_EXEC)) == (FLG_OF_STATIC | FLG_OF_EXEC)) return (1); /* * If no relocation cache structures are available allocate * a new one and link it into the cache list. */ if ((ofl->ofl_outrels.tail == 0) || ((rcp = (Rel_cache *)ofl->ofl_outrels.tail->data) == 0) || ((orsp = rcp->rc_free) == rcp->rc_end)) { static size_t nextsize = 0; size_t size; /* * Output relocation numbers can vary considerably between * building executables or shared objects (pic vs. non-pic), * etc. But, they typically aren't very large, so for these * objects use a standard bucket size. For building relocatable * objects, typically there will be an output relocation for * every input relocation. */ if (nextsize == 0) { if (ofl->ofl_flags & FLG_OF_RELOBJ) { if ((size = ofl->ofl_relocincnt) == 0) size = REL_LOIDESCNO; if (size > REL_HOIDESCNO) nextsize = REL_HOIDESCNO; else nextsize = REL_LOIDESCNO; } else nextsize = size = REL_HOIDESCNO; } else size = nextsize; size = size * sizeof (Rel_desc); if (((rcp = libld_malloc(sizeof (Rel_cache) + size)) == 0) || (list_appendc(&ofl->ofl_outrels, rcp) == 0)) return (S_ERROR); /* LINTED */ rcp->rc_free = orsp = (Rel_desc *)(rcp + 1); /* LINTED */ rcp->rc_end = (Rel_desc *)((char *)rcp->rc_free + size); } /* * If we are adding a output relocation against a section * symbol (non-RELATIVE) then mark that section. These sections * will be added to the .dynsym symbol table. */ if (sdp && (rsp->rel_rtype != M_R_RELATIVE) && ((flags & FLG_REL_SCNNDX) || (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) { /* * If this is a COMMON symbol - no output section * exists yet - (it's created as part of sym_validate()). * So - we mark here that when it's created it should * be tagged with the FLG_OS_OUTREL flag. */ if ((sdp->sd_flags & FLG_SY_SPECSEC) && (sdp->sd_sym->st_shndx == SHN_COMMON)) { if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS) ofl->ofl_flags1 |= FLG_OF1_BSSOREL; else ofl->ofl_flags1 |= FLG_OF1_TLSOREL; } else { Os_desc *osp = sdp->sd_isc->is_osdesc; if (osp && ((osp->os_flags & FLG_OS_OUTREL) == 0)) { ofl->ofl_dynshdrcnt++; osp->os_flags |= FLG_OS_OUTREL; } } } *orsp = *rsp; orsp->rel_flags |= flags; rcp->rc_free++; ofl->ofl_outrelscnt++; if (flags & FLG_REL_GOT) ofl->ofl_relocgotsz += (Xword)sizeof (Rel); else if (flags & FLG_REL_PLT) ofl->ofl_relocpltsz += (Xword)sizeof (Rel); else if (flags & FLG_REL_BSS) ofl->ofl_relocbsssz += (Xword)sizeof (Rel); else if (flags & FLG_REL_NOINFO) ofl->ofl_relocrelsz += (Xword)sizeof (Rel); else orsp->rel_osdesc->os_szoutrels += (Xword)sizeof (Rel); if (orsp->rel_rtype == M_R_RELATIVE) ofl->ofl_relocrelcnt++; /* * We don't perform sorting on PLT relocations because * they have already been assigned a PLT index and if we * were to sort them we would have to re-assign the plt indexes. */ if (!(flags & FLG_REL_PLT)) ofl->ofl_reloccnt++; /* * Insure a GLOBAL_OFFSET_TABLE is generated if required. */ if (IS_GOT_REQUIRED(orsp->rel_rtype)) ofl->ofl_flags |= FLG_OF_BLDGOT; /* * Identify and possibly warn of a displacement relocation. */ if (orsp->rel_flags & FLG_REL_DISP) { ofl->ofl_dtflags_1 |= DF_1_DISPRELPND; if (ofl->ofl_flags & FLG_OF_VERBOSE) ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl); } DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_REL, M_MACH, orsp)); return (1); } /* * Stub routine since register symbols are not supported on i386. */ /* ARGSUSED */ uintptr_t ld_reloc_register(Rel_desc * rsp, Is_desc * isp, Ofl_desc * ofl) { eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_REL_NOREG)); return (S_ERROR); } /* * process relocation for a LOCAL symbol */ uintptr_t ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl) { Word flags = ofl->ofl_flags; Sym_desc *sdp = rsp->rel_sym; Word shndx = sdp->sd_sym->st_shndx; /* * if ((shared object) and (not pc relative relocation) and * (not against ABS symbol)) * then * build R_386_RELATIVE * fi */ if ((flags & FLG_OF_SHAROBJ) && (rsp->rel_flags & FLG_REL_LOAD) && !(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_GOT_BASED(rsp->rel_rtype)) && !(rsp->rel_isdesc != NULL && (rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) && (((sdp->sd_flags & FLG_SY_SPECSEC) == 0) || (shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) { Word ortype = rsp->rel_rtype; rsp->rel_rtype = R_386_RELATIVE; if (ld_add_outrel(NULL, rsp, ofl) == S_ERROR) return (S_ERROR); rsp->rel_rtype = ortype; } /* * If the relocation is against a 'non-allocatable' section * and we can not resolve it now - then give a warning * message. * * We can not resolve the symbol if either: * a) it's undefined * b) it's defined in a shared library and a * COPY relocation hasn't moved it to the executable * * Note: because we process all of the relocations against the * text segment before any others - we know whether * or not a copy relocation will be generated before * we get here (see reloc_init()->reloc_segments()). */ if (!(rsp->rel_flags & FLG_REL_LOAD) && ((shndx == SHN_UNDEF) || ((sdp->sd_ref == REF_DYN_NEED) && ((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) { /* * If the relocation is against a SHT_SUNW_ANNOTATE * section - then silently ignore that the relocation * can not be resolved. */ if (rsp->rel_osdesc && (rsp->rel_osdesc->os_shdr->sh_type == SHT_SUNW_ANNOTATE)) return (0); eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_REL_EXTERNSYM), conv_reloc_386_type(rsp->rel_rtype, 0), rsp->rel_isdesc->is_file->ifl_name, demangle(rsp->rel_sname), rsp->rel_osdesc->os_name); return (1); } /* * Perform relocation. */ return (ld_add_actrel(NULL, rsp, ofl)); } uintptr_t /* ARGSUSED */ ld_reloc_GOTOP(Boolean local, Rel_desc * rsp, Ofl_desc * ofl) { /* * Stub routine for common code compatibility, we shouldn't * actually get here on x86. */ assert(0); return (S_ERROR); } uintptr_t ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl) { Word rtype = rsp->rel_rtype; Sym_desc *sdp = rsp->rel_sym; Word flags = ofl->ofl_flags; Gotndx *gnp; /* * If we're building an executable - use either the IE or LE access * model. If we're building a shared object process any IE model. */ if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) { /* * Set the DF_STATIC_TLS flag. */ ofl->ofl_dtflags |= DF_STATIC_TLS; if (!local || ((flags & FLG_OF_EXEC) == 0)) { /* * Assign a GOT entry for static TLS references. */ if ((gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), GOT_REF_TLSIE, ofl, 0)) == 0) { if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSIE, FLG_REL_STLS, rtype, R_386_TLS_TPOFF, 0) == S_ERROR) return (S_ERROR); } /* * IE access model. */ if (IS_TLS_IE(rtype)) { if (ld_add_actrel(FLG_REL_STLS, rsp, ofl) == S_ERROR) return (S_ERROR); /* * A non-pic shared object needs to adjust the * active relocation (indntpoff). */ if (((flags & FLG_OF_EXEC) == 0) && (rtype == R_386_TLS_IE)) { rsp->rel_rtype = R_386_RELATIVE; return (ld_add_outrel(NULL, rsp, ofl)); } return (1); } /* * Fixups are required for other executable models. */ return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), rsp, ofl)); } /* * LE access model. */ if (IS_TLS_LE(rtype) || (rtype == R_386_TLS_LDO_32)) return (ld_add_actrel(FLG_REL_STLS, rsp, ofl)); return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS), rsp, ofl)); } /* * Building a shared object. * * Assign a GOT entry for a dynamic TLS reference. */ if (IS_TLS_LD(rtype) && ((gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), GOT_REF_TLSLD, ofl, 0)) == 0)) { if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD, FLG_REL_MTLS, rtype, R_386_TLS_DTPMOD32, 0) == S_ERROR) return (S_ERROR); } else if (IS_TLS_GD(rtype) && ((gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), GOT_REF_TLSGD, ofl, 0)) == 0)) { if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD, FLG_REL_DTLS, rtype, R_386_TLS_DTPMOD32, R_386_TLS_DTPOFF32) == S_ERROR) return (S_ERROR); } /* * For GD/LD TLS reference - TLS_{GD,LD}_CALL, this will eventually * cause a call to __tls_get_addr(). Convert this relocation to that * symbol now, and prepare for the PLT magic. */ if ((rtype == R_386_TLS_GD_PLT) || (rtype == R_386_TLS_LDM_PLT)) { Sym_desc * tlsgetsym; if ((tlsgetsym = ld_sym_add_u(MSG_ORIG(MSG_SYM_TLSGETADDR_UU), ofl)) == (Sym_desc *)S_ERROR) return (S_ERROR); rsp->rel_sym = tlsgetsym; rsp->rel_sname = tlsgetsym->sd_name; rsp->rel_rtype = R_386_PLT32; if (ld_reloc_plt(rsp, ofl) == S_ERROR) return (S_ERROR); rsp->rel_sym = sdp; rsp->rel_sname = sdp->sd_name; rsp->rel_rtype = rtype; return (1); } if (IS_TLS_LD(rtype)) return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl)); return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl)); } /* ARGSUSED3 */ Gotndx * ld_find_gotndx(List * lst, Gotref gref, Ofl_desc * ofl, Rel_desc * rdesc) { Listnode * lnp; Gotndx * gnp; if ((gref == GOT_REF_TLSLD) && ofl->ofl_tlsldgotndx) return (ofl->ofl_tlsldgotndx); for (LIST_TRAVERSE(lst, lnp, gnp)) { if (gnp->gn_gotref == gref) return (gnp); } return ((Gotndx *)0); } Xword ld_calc_got_offset(Rel_desc * rdesc, Ofl_desc * ofl) { Os_desc *osp = ofl->ofl_osgot; Sym_desc *sdp = rdesc->rel_sym; Xword gotndx; Gotref gref; Gotndx *gnp; if (rdesc->rel_flags & FLG_REL_DTLS) gref = GOT_REF_TLSGD; else if (rdesc->rel_flags & FLG_REL_MTLS) gref = GOT_REF_TLSLD; else if (rdesc->rel_flags & FLG_REL_STLS) gref = GOT_REF_TLSIE; else gref = GOT_REF_GENERIC; gnp = ld_find_gotndx(&(sdp->sd_GOTndxs), gref, ofl, 0); assert(gnp); gotndx = (Xword)gnp->gn_gotndx; if ((rdesc->rel_flags & FLG_REL_DTLS) && (rdesc->rel_rtype == R_386_TLS_DTPOFF32)) gotndx++; return ((Xword)(osp->os_shdr->sh_addr + (gotndx * M_GOT_ENTSIZE))); } /* ARGSUSED4 */ uintptr_t ld_assign_got_ndx(List * lst, Gotndx * pgnp, Gotref gref, Ofl_desc * ofl, Rel_desc * rsp, Sym_desc * sdp) { Gotndx *gnp; uint_t gotents; if (pgnp) return (1); if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD)) gotents = 2; else gotents = 1; if ((gnp = libld_calloc(sizeof (Gotndx), 1)) == 0) return (S_ERROR); gnp->gn_gotndx = ofl->ofl_gotcnt; gnp->gn_gotref = gref; ofl->ofl_gotcnt += gotents; if (gref == GOT_REF_TLSLD) { ofl->ofl_tlsldgotndx = gnp; return (1); } if (list_appendc(lst, (void *)gnp) == 0) return (S_ERROR); return (1); } void ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl) { sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++; sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++; ofl->ofl_flags |= FLG_OF_BLDGOT; } /* * Initializes .got[0] with the _DYNAMIC symbol value. */ uintptr_t ld_fillin_gotplt(Ofl_desc *ofl) { Word flags = ofl->ofl_flags; if (ofl->ofl_osgot) { Sym_desc *sdp; if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U), SYM_NOHASH, 0, ofl)) != NULL) { uchar_t *genptr; genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf + (M_GOT_XDYNAMIC * M_GOT_ENTSIZE)); /* LINTED */ *(Word *)genptr = (Word)sdp->sd_sym->st_value; } } /* * Fill in the reserved slot in the procedure linkage table the first * entry is: * if (building a.out) { * PUSHL got[1] # the address of the link map entry * JMP * got[2] # the address of rtbinder * } else { * PUSHL got[1]@GOT(%ebx) # the address of the link map entry * JMP * got[2]@GOT(%ebx) # the address of rtbinder * } */ if ((flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) { uchar_t *pltent; pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf; if (!(flags & FLG_OF_SHAROBJ)) { pltent[0] = M_SPECIAL_INST; pltent[1] = M_PUSHL_DISP; pltent += 2; /* LINTED */ *(Word *)pltent = (Word)(ofl->ofl_osgot->os_shdr-> sh_addr + M_GOT_XLINKMAP * M_GOT_ENTSIZE); pltent += 4; pltent[0] = M_SPECIAL_INST; pltent[1] = M_JMP_DISP_IND; pltent += 2; /* LINTED */ *(Word *)pltent = (Word)(ofl->ofl_osgot->os_shdr-> sh_addr + M_GOT_XRTLD * M_GOT_ENTSIZE); } else { pltent[0] = M_SPECIAL_INST; pltent[1] = M_PUSHL_REG_DISP; pltent += 2; /* LINTED */ *(Word *)pltent = (Word)(M_GOT_XLINKMAP * M_GOT_ENTSIZE); pltent += 4; pltent[0] = M_SPECIAL_INST; pltent[1] = M_JMP_REG_DISP_IND; pltent += 2; /* LINTED */ *(Word *)pltent = (Word)(M_GOT_XRTLD * M_GOT_ENTSIZE); } } return (1); }