1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 /* 27 * Object file dependent support for ELF objects. 28 */ 29 30 #include <stdio.h> 31 #include <sys/procfs.h> 32 #include <sys/mman.h> 33 #include <dlfcn.h> 34 #include <debug.h> 35 #include <conv.h> 36 #include "_rtld.h" 37 #include "_audit.h" 38 #include "_elf.h" 39 #include "_inline_gen.h" 40 #include "msg.h" 41 42 /* 43 * For backward compatibility copy relocation processing, it can be necessary to 44 * determine if a copy destination is also the recipient of a move record. For 45 * these instances, the move record addresses are retained for is_move_data(). 46 */ 47 static APlist *alp = NULL; 48 49 /* 50 * Warning message for bad move target. 51 */ 52 void 53 elf_move_bad(Lm_list *lml, Rt_map *lmp, Sym *sym, ulong_t num, Addr addr) 54 { 55 const char *name; 56 int trace; 57 58 trace = (lml->lm_flags & LML_FLG_TRC_ENABLE) && 59 (((rtld_flags & RT_FL_SILENCERR) == 0) || 60 (lml->lm_flags & (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_WARN))); 61 62 if ((trace == 0) && (DBG_ENABLED == 0)) 63 return; 64 65 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 66 name = (const char *)(STRTAB(lmp) + sym->st_name); 67 else 68 name = MSG_INTL(MSG_STR_UNKNOWN); 69 70 if (trace) 71 (void) printf(MSG_INTL(MSG_LDD_MOVE_ERR), EC_XWORD(num), name, 72 EC_ADDR(addr)); 73 else 74 DBG_CALL(Dbg_move_bad(lml, num, name, addr)); 75 } 76 77 /* 78 * Move data. Apply sparse initialization to data in zeroed bss. 79 */ 80 int 81 move_data(Rt_map *lmp, APlist **textrel) 82 { 83 Lm_list *lml = LIST(lmp); 84 Move *mv = MOVETAB(lmp); 85 ulong_t num, mvnum = MOVESZ(lmp) / MOVEENT(lmp); 86 int moves; 87 88 /* 89 * If these records are against the executable, and the executable was 90 * built prior to Solaris 8, keep track of the move record symbol. See 91 * comment in analyze.c:lookup_sym_interpose() in regards Solaris 8 92 * objects and DT_FLAGS. 93 */ 94 moves = (lmp == lml->lm_head) && ((FLAGS1(lmp) & FL1_RT_DTFLAGS) == 0); 95 96 DBG_CALL(Dbg_move_data(lmp)); 97 for (num = 0; num < mvnum; num++, mv++) { 98 mmapobj_result_t *mpp; 99 Addr addr, taddr; 100 Half rep, repno, stride; 101 Sym *sym; 102 103 if ((sym = (Sym *)SYMTAB(lmp) + ELF_M_SYM(mv->m_info)) == 0) 104 continue; 105 106 stride = mv->m_stride + 1; 107 addr = sym->st_value; 108 109 /* 110 * Determine the move data target, and verify the address is 111 * writable. 112 */ 113 if ((FLAGS(lmp) & FLG_RT_FIXED) == 0) 114 addr += ADDR(lmp); 115 taddr = addr + mv->m_poffset; 116 117 if ((mpp = find_segment((caddr_t)taddr, lmp)) == NULL) { 118 elf_move_bad(lml, lmp, sym, num, taddr); 119 continue; 120 } 121 if (((mpp->mr_prot & PROT_WRITE) == 0) && 122 ((set_prot(lmp, mpp, 1) == 0) || 123 (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) 124 return (0); 125 126 DBG_CALL(Dbg_move_entry2(lml, mv, sym->st_name, 127 (const char *)(sym->st_name + STRTAB(lmp)))); 128 129 for (rep = 0, repno = 0; rep < mv->m_repeat; rep++) { 130 DBG_CALL(Dbg_move_expand(lml, mv, taddr)); 131 132 switch (ELF_M_SIZE(mv->m_info)) { 133 case 1: 134 *((char *)taddr) = (char)mv->m_value; 135 taddr += stride; 136 repno++; 137 break; 138 case 2: 139 /* LINTED */ 140 *((Half *)taddr) = (Half)mv->m_value; 141 taddr += 2 * stride; 142 repno++; 143 break; 144 case 4: 145 /* LINTED */ 146 *((Word *)taddr) = (Word)mv->m_value; 147 taddr += 4 * stride; 148 repno++; 149 break; 150 case 8: 151 /* LINTED */ 152 *((unsigned long long *)taddr) = mv->m_value; 153 taddr += 8 * stride; 154 repno++; 155 break; 156 default: 157 eprintf(lml, ERR_NONE, MSG_INTL(MSG_MOVE_ERR1)); 158 break; 159 } 160 } 161 162 /* 163 * If any move records have been applied to this symbol, retain 164 * the symbol address if required for backward compatibility 165 * copy relocation processing. 166 */ 167 if (moves && repno && 168 (aplist_append(&alp, (void *)addr, AL_CNT_MOVES) == NULL)) 169 return (0); 170 } 171 172 /* 173 * Binaries built in the early 1990's prior to Solaris 8, using the ild 174 * incremental linker are known to have zero filled move sections 175 * (presumably place holders for new, incoming move sections). If no 176 * move records have been processed, remove the move identifier to 177 * optimize the amount of backward compatibility copy relocation 178 * processing that is needed. 179 */ 180 if (moves && (alp == NULL)) 181 FLAGS(lmp) &= ~FLG_RT_MOVE; 182 183 return (1); 184 } 185 186 /* 187 * Determine whether an address is the recipient of a move record. 188 * Returns 1 if the address matches a move symbol, 0 otherwise. 189 */ 190 int 191 is_move_data(caddr_t addr) 192 { 193 caddr_t maddr; 194 Aliste idx; 195 196 for (APLIST_TRAVERSE(alp, idx, maddr)) { 197 if (addr == maddr) 198 return (1); 199 } 200 return (0); 201 } 202