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 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Object file dependent support for ELF objects. 29 */ 30 31 #include <stdio.h> 32 #include <sys/procfs.h> 33 #include <sys/mman.h> 34 #include <dlfcn.h> 35 #include <debug.h> 36 #include <conv.h> 37 #include "_rtld.h" 38 #include "_audit.h" 39 #include "_elf.h" 40 #include "_inline.h" 41 #include "msg.h" 42 43 /* 44 * For backward compatibility copy relocation processing, it can be necessary to 45 * determine if a copy destination is also the recipient of a move record. For 46 * these instances, the move record addresses are retained for is_move_data(). 47 */ 48 static APlist *alp = NULL; 49 50 /* 51 * Warning message for bad move target. 52 */ 53 void 54 elf_move_bad(Lm_list *lml, Rt_map *lmp, Sym *sym, ulong_t num, Addr addr) 55 { 56 const char *name; 57 int trace; 58 59 trace = (lml->lm_flags & LML_FLG_TRC_ENABLE) && 60 (((rtld_flags & RT_FL_SILENCERR) == 0) || 61 (lml->lm_flags & (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_WARN))); 62 63 if ((trace == 0) && (DBG_ENABLED == 0)) 64 return; 65 66 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 67 name = (const char *)(STRTAB(lmp) + sym->st_name); 68 else 69 name = MSG_INTL(MSG_STR_UNKNOWN); 70 71 if (trace) 72 (void) printf(MSG_INTL(MSG_LDD_MOVE_ERR), EC_XWORD(num), name, 73 EC_ADDR(addr)); 74 else 75 DBG_CALL(Dbg_move_bad(lml, num, name, addr)); 76 } 77 78 /* 79 * Move data. Apply sparse initialization to data in zeroed bss. 80 */ 81 int 82 move_data(Rt_map *lmp, APlist **textrel) 83 { 84 Lm_list *lml = LIST(lmp); 85 Move *mv = MOVETAB(lmp); 86 ulong_t num, mvnum = MOVESZ(lmp) / MOVEENT(lmp); 87 int moves; 88 89 /* 90 * If these records are against the executable, and the executable was 91 * built prior to Solaris 8, keep track of the move record symbol. See 92 * comment in analyze.c:lookup_sym_interpose() in regards Solaris 8 93 * objects and DT_FLAGS. 94 */ 95 moves = (lmp == lml->lm_head) && ((FLAGS1(lmp) & FL1_RT_DTFLAGS) == 0); 96 97 DBG_CALL(Dbg_move_data(lmp)); 98 for (num = 0; num < mvnum; num++, mv++) { 99 mmapobj_result_t *mpp; 100 Addr addr, taddr; 101 Half rep, repno, stride; 102 Sym *sym; 103 104 if ((sym = (Sym *)SYMTAB(lmp) + ELF_M_SYM(mv->m_info)) == 0) 105 continue; 106 107 stride = mv->m_stride + 1; 108 addr = sym->st_value; 109 110 /* 111 * Determine the move data target, and verify the address is 112 * writable. 113 */ 114 if ((FLAGS(lmp) & FLG_RT_FIXED) == 0) 115 addr += ADDR(lmp); 116 taddr = addr + mv->m_poffset; 117 118 if ((mpp = find_segment((caddr_t)taddr, lmp)) == NULL) { 119 elf_move_bad(lml, lmp, sym, num, taddr); 120 continue; 121 } 122 if (((mpp->mr_prot & PROT_WRITE) == 0) && 123 ((set_prot(lmp, mpp, 1) == 0) || 124 (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) 125 return (0); 126 127 DBG_CALL(Dbg_move_entry2(lml, mv, sym->st_name, 128 (const char *)(sym->st_name + STRTAB(lmp)))); 129 130 for (rep = 0, repno = 0; rep < mv->m_repeat; rep++) { 131 DBG_CALL(Dbg_move_expand(lml, mv, taddr)); 132 133 switch (ELF_M_SIZE(mv->m_info)) { 134 case 1: 135 *((char *)taddr) = (char)mv->m_value; 136 taddr += stride; 137 repno++; 138 break; 139 case 2: 140 /* LINTED */ 141 *((Half *)taddr) = (Half)mv->m_value; 142 taddr += 2 * stride; 143 repno++; 144 break; 145 case 4: 146 /* LINTED */ 147 *((Word *)taddr) = (Word)mv->m_value; 148 taddr += 4 * stride; 149 repno++; 150 break; 151 case 8: 152 /* LINTED */ 153 *((unsigned long long *)taddr) = mv->m_value; 154 taddr += 8 * stride; 155 repno++; 156 break; 157 default: 158 eprintf(lml, ERR_NONE, MSG_INTL(MSG_MOVE_ERR1)); 159 break; 160 } 161 } 162 163 /* 164 * If any move records have been applied to this symbol, retain 165 * the symbol address if required for backward compatibility 166 * copy relocation processing. 167 */ 168 if (moves && repno && 169 (aplist_append(&alp, (void *)addr, AL_CNT_MOVES) == NULL)) 170 return (0); 171 } 172 173 /* 174 * Binaries built in the early 1990's prior to Solaris 8, using the ild 175 * incremental linker are known to have zero filled move sections 176 * (presumably place holders for new, incoming move sections). If no 177 * move records have been processed, remove the move identifier to 178 * optimize the amount of backward compatibility copy relocation 179 * processing that is needed. 180 */ 181 if (moves && (alp == NULL)) 182 FLAGS(lmp) &= ~FLG_RT_MOVE; 183 184 return (1); 185 } 186 187 /* 188 * Determine whether an address is the recipient of a move record. 189 * Returns 1 if the address matches a move symbol, 0 otherwise. 190 */ 191 int 192 is_move_data(caddr_t addr) 193 { 194 caddr_t maddr; 195 Aliste idx; 196 197 for (APLIST_TRAVERSE(alp, idx, maddr)) { 198 if (addr == maddr) 199 return (1); 200 } 201 return (0); 202 } 203