uClibc: add support for mips non-pic relocations in ldso
[openwrt/openwrt.git] / toolchain / uClibc / patches-0.9.30.1 / 440-backport_mips_nonpic.patch
1 --- a/include/elf.h
2 +++ b/include/elf.h
3 @@ -1547,6 +1547,7 @@ typedef struct
4 #define STO_MIPS_INTERNAL 0x1
5 #define STO_MIPS_HIDDEN 0x2
6 #define STO_MIPS_PROTECTED 0x3
7 +#define STO_MIPS_PLT 0x8
8 #define STO_MIPS_SC_ALIGN_UNUSED 0xff
9
10 /* MIPS specific values for `st_info'. */
11 @@ -1692,8 +1693,11 @@ typedef struct
12 #define R_MIPS_TLS_TPREL64 48 /* TP-relative offset, 64 bit */
13 #define R_MIPS_TLS_TPREL_HI16 49 /* TP-relative offset, high 16 bits */
14 #define R_MIPS_TLS_TPREL_LO16 50 /* TP-relative offset, low 16 bits */
15 +#define R_MIPS_GLOB_DAT 51
16 +#define R_MIPS_COPY 126
17 +#define R_MIPS_JUMP_SLOT 127
18 /* Keep this the last entry. */
19 -#define R_MIPS_NUM 51
20 +#define R_MIPS_NUM 128
21
22 /* Legal values for p_type field of Elf32_Phdr. */
23
24 @@ -1759,7 +1763,13 @@ typedef struct
25 #define DT_MIPS_COMPACT_SIZE 0x7000002f /* (O32)Size of compact rel section. */
26 #define DT_MIPS_GP_VALUE 0x70000030 /* GP value for aux GOTs. */
27 #define DT_MIPS_AUX_DYNAMIC 0x70000031 /* Address of aux .dynamic. */
28 -#define DT_MIPS_NUM 0x32
29 +/* The address of .got.plt in an executable using the new non-PIC ABI. */
30 +#define DT_MIPS_PLTGOT 0x70000032
31 +/* The base of the PLT in an executable using the new non-PIC ABI if that
32 + PLT is writable. For a non-writable PLT, this is omitted or has a zero
33 + value. */
34 +#define DT_MIPS_RWPLT 0x70000034
35 +#define DT_MIPS_NUM 0x35
36
37 /* Legal values for DT_MIPS_FLAGS Elf32_Dyn entry. */
38
39 --- a/ldso/ldso/dl-hash.c
40 +++ b/ldso/ldso/dl-hash.c
41 @@ -160,6 +160,11 @@ check_match (const ElfW(Sym) *sym, char
42 /* undefined symbol itself */
43 return NULL;
44
45 +#ifdef __mips__
46 + if (sym->st_shndx == SHN_UNDEF && !(sym->st_other & STO_MIPS_PLT))
47 + return NULL;
48 +#endif
49 +
50 if (sym->st_value == 0)
51 /* No value */
52 return NULL;
53 --- a/ldso/ldso/mips/dl-sysdep.h
54 +++ b/ldso/ldso/mips/dl-sysdep.h
55 @@ -93,10 +93,11 @@ typedef struct
56
57 #include <link.h>
58
59 -#define ARCH_NUM 3
60 +#define ARCH_NUM 4
61 #define DT_MIPS_GOTSYM_IDX (DT_NUM + OS_NUM)
62 #define DT_MIPS_LOCAL_GOTNO_IDX (DT_NUM + OS_NUM +1)
63 #define DT_MIPS_SYMTABNO_IDX (DT_NUM + OS_NUM +2)
64 +#define DT_MIPS_PLTGOT_IDX (DT_NUM + OS_NUM +3)
65
66 #define ARCH_DYNAMIC_INFO(dpnt, dynamic, debug_addr) \
67 do { \
68 @@ -106,6 +107,8 @@ else if (dpnt->d_tag == DT_MIPS_LOCAL_GO
69 dynamic[DT_MIPS_LOCAL_GOTNO_IDX] = dpnt->d_un.d_val; \
70 else if (dpnt->d_tag == DT_MIPS_SYMTABNO) \
71 dynamic[DT_MIPS_SYMTABNO_IDX] = dpnt->d_un.d_val; \
72 +else if (dpnt->d_tag == DT_MIPS_PLTGOT) \
73 + dynamic[DT_MIPS_PLTGOT_IDX] = dpnt->d_un.d_val; \
74 else if (dpnt->d_tag == DT_MIPS_RLD_MAP) \
75 *(ElfW(Addr) *)(dpnt->d_un.d_ptr) = (ElfW(Addr)) debug_addr; \
76 } while (0)
77 @@ -114,6 +117,7 @@ else if (dpnt->d_tag == DT_MIPS_RLD_MAP)
78 #define INIT_GOT(GOT_BASE,MODULE) \
79 do { \
80 unsigned long idx; \
81 + unsigned long *pltgot; \
82 \
83 /* Check if this is the dynamic linker itself */ \
84 if (MODULE->libtype == program_interpreter) \
85 @@ -123,6 +127,12 @@ do { \
86 GOT_BASE[0] = (unsigned long) _dl_runtime_resolve; \
87 GOT_BASE[1] = (unsigned long) MODULE; \
88 \
89 + pltgot = MODULE->dynamic_info[DT_MIPS_PLTGOT_IDX]; \
90 + if (pltgot) { \
91 + pltgot[0] = (unsigned long) _dl_runtime_pltresolve; \
92 + pltgot[1] = (unsigned long) MODULE; \
93 + } \
94 + \
95 /* Add load address displacement to all local GOT entries */ \
96 idx = 2; \
97 while (idx < MODULE->dynamic_info[DT_MIPS_LOCAL_GOTNO_IDX]) \
98 @@ -157,9 +167,9 @@ void _dl_perform_mips_global_got_relocat
99 #define OFFS_ALIGN 0x7ffff000
100 #endif /* O32 || N32 */
101
102 -#define elf_machine_type_class(type) ELF_RTYPE_CLASS_PLT
103 -/* MIPS does not have COPY relocs */
104 -#define DL_NO_COPY_RELOCS
105 +#define elf_machine_type_class(type) \
106 + ((((type) == R_MIPS_JUMP_SLOT) * ELF_RTYPE_CLASS_PLT) \
107 + | (((type) == R_MIPS_COPY) * ELF_RTYPE_CLASS_COPY))
108
109 #define OFFSET_GP_GOT 0x7ff0
110
111 --- a/ldso/ldso/mips/elfinterp.c
112 +++ b/ldso/ldso/mips/elfinterp.c
113 @@ -30,6 +30,7 @@
114 #include "ldso.h"
115
116 extern int _dl_runtime_resolve(void);
117 +extern int _dl_runtime_pltresolve(void);
118
119 #define OFFSET_GP_GOT 0x7ff0
120
121 @@ -83,6 +84,61 @@ unsigned long __dl_runtime_resolve(unsig
122 return new_addr;
123 }
124
125 +unsigned long
126 +__dl_runtime_pltresolve(struct elf_resolve *tpnt, int reloc_entry)
127 +{
128 + int reloc_type;
129 + ELF_RELOC *this_reloc;
130 + char *strtab;
131 + Elf32_Sym *symtab;
132 + int symtab_index;
133 + char *rel_addr;
134 + char *new_addr;
135 + char **got_addr;
136 + unsigned long instr_addr;
137 + char *symname;
138 +
139 + rel_addr = (char *)tpnt->dynamic_info[DT_JMPREL];
140 + this_reloc = (ELF_RELOC *)(intptr_t)(rel_addr + reloc_entry);
141 + reloc_type = ELF32_R_TYPE(this_reloc->r_info);
142 + symtab_index = ELF32_R_SYM(this_reloc->r_info);
143 +
144 + symtab = (Elf32_Sym *)(intptr_t)tpnt->dynamic_info[DT_SYMTAB];
145 + strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
146 + symname = strtab + symtab[symtab_index].st_name;
147 +
148 + /* Address of the jump instruction to fix up. */
149 + instr_addr = ((unsigned long)this_reloc->r_offset +
150 + (unsigned long)tpnt->loadaddr);
151 + got_addr = (char **)instr_addr;
152 +
153 + /* Get the address of the GOT entry. */
154 + new_addr = _dl_find_hash(symname, tpnt->symbol_scope, tpnt, ELF_RTYPE_CLASS_PLT);
155 + if (unlikely(!new_addr)) {
156 + _dl_dprintf(2, "%s: can't resolve symbol '%s' in lib '%s'.\n", _dl_progname, symname, tpnt->libname);
157 + _dl_exit(1);
158 + }
159 +
160 +#if defined (__SUPPORT_LD_DEBUG__)
161 + if ((unsigned long)got_addr < 0x40000000) {
162 + if (_dl_debug_bindings) {
163 + _dl_dprintf(_dl_debug_file, "\nresolve function: %s", symname);
164 + if (_dl_debug_detail)
165 + _dl_dprintf(_dl_debug_file,
166 + "\n\tpatched: %x ==> %x @ %x",
167 + *got_addr, new_addr, got_addr);
168 + }
169 + }
170 + if (!_dl_debug_nofixups) {
171 + *got_addr = new_addr;
172 + }
173 +#else
174 + *got_addr = new_addr;
175 +#endif
176 +
177 + return (unsigned long)new_addr;
178 +}
179 +
180 void _dl_parse_lazy_relocation_information(struct dyn_elf *rpnt,
181 unsigned long rel_addr, unsigned long rel_size)
182 {
183 @@ -115,6 +171,7 @@ int _dl_parse_relocation_information(str
184 got = (unsigned long *) tpnt->dynamic_info[DT_PLTGOT];
185
186 for (i = 0; i < rel_size; i++, rpnt++) {
187 + char *symname = NULL;
188 reloc_addr = (unsigned long *) (tpnt->loadaddr +
189 (unsigned long) rpnt->r_offset);
190 reloc_type = ELF_R_TYPE(rpnt->r_info);
191 @@ -128,6 +185,16 @@ int _dl_parse_relocation_information(str
192 old_val = *reloc_addr;
193 #endif
194
195 + if (reloc_type == R_MIPS_JUMP_SLOT || reloc_type == R_MIPS_COPY) {
196 + symname = strtab + symtab[symtab_index].st_name;
197 + symbol_addr = (unsigned long)_dl_find_hash(symname,
198 + tpnt->symbol_scope,
199 + tpnt,
200 + elf_machine_type_class(reloc_type));
201 + if (unlikely(!symbol_addr && ELF32_ST_BIND(symtab[symtab_index].st_info) != STB_WEAK))
202 + return 1;
203 + }
204 +
205 switch (reloc_type) {
206 #if _MIPS_SIM == _MIPS_SIM_ABI64
207 case (R_MIPS_64 << 8) | R_MIPS_REL32:
208 @@ -148,6 +215,24 @@ int _dl_parse_relocation_information(str
209 *reloc_addr += (unsigned long) tpnt->loadaddr;
210 }
211 break;
212 + case R_MIPS_JUMP_SLOT:
213 + *reloc_addr = symbol_addr;
214 + break;
215 + case R_MIPS_COPY:
216 + if (symbol_addr) {
217 +#if defined (__SUPPORT_LD_DEBUG__)
218 + if (_dl_debug_move)
219 + _dl_dprintf(_dl_debug_file,
220 + "\n%s move %d bytes from %x to %x",
221 + symname, symtab[symtab_index].st_size,
222 + symbol_addr, reloc_addr);
223 +#endif
224 +
225 + _dl_memcpy((char *)reloc_addr,
226 + (char *)symbol_addr,
227 + symtab[symtab_index].st_size);
228 + }
229 + break;
230 case R_MIPS_NONE:
231 break;
232 default:
233 --- a/ldso/ldso/mips/resolve.S
234 +++ b/ldso/ldso/mips/resolve.S
235 @@ -112,3 +112,54 @@ _dl_runtime_resolve:
236 .end _dl_runtime_resolve
237 .previous
238
239 +/* Assembler veneer called from the PLT header code when using the
240 + non-PIC ABI.
241 +
242 + Code in each PLT entry puts the caller's return address into t7 ($15),
243 + the PLT entry index into t8 ($24), the address of _dl_runtime_pltresolve
244 + into t9 ($25) and the address of .got.plt into gp ($28). __dl_runtime_pltresolve
245 + needs a0 ($4) to hold the link map and a1 ($5) to hold the index into
246 + .rel.plt (== PLT entry index * 4). */
247 +
248 + .text
249 + .align 2
250 + .globl _dl_runtime_pltresolve
251 + .type _dl_runtime_pltresolve,@function
252 + .ent _dl_runtime_pltresolve
253 +_dl_runtime_pltresolve:
254 + .frame $29, 40, $31
255 + .set noreorder
256 + # Save arguments and sp value in stack.
257 + subu $29, 40
258 + lw $10, 4($28)
259 + # Modify t9 ($25) so as to point .cpload instruction.
260 + addiu $25, 12
261 + # Compute GP.
262 + .cpload $25
263 + .set reorder
264 +
265 + /* Store function arguments from registers to stack */
266 + sw $15, 36($29)
267 + sw $4, 16($29)
268 + sw $5, 20($29)
269 + sw $6, 24($29)
270 + sw $7, 28($29)
271 +
272 + /* Setup functions args and call __dl_runtime_pltresolve. */
273 + move $4, $10
274 + sll $5, $24, 3
275 + jal __dl_runtime_pltresolve
276 +
277 + /* Restore function arguments from stack to registers */
278 + lw $31, 36($29)
279 + lw $4, 16($29)
280 + lw $5, 20($29)
281 + lw $6, 24($29)
282 + lw $7, 28($29)
283 +
284 + /* Do a tail call to the original function */
285 + addiu $29, 40
286 + move $25, $2
287 + jr $25
288 + .end _dl_runtime_pltresolve
289 + .previous