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b886d83c | 1 | // SPDX-License-Identifier: GPL-2.0-only |
a2c7a983 IM |
2 | /* |
3 | * bpf_jit_comp.c: BPF JIT compiler | |
0a14842f | 4 | * |
3b58908a | 5 | * Copyright (C) 2011-2013 Eric Dumazet (eric.dumazet@gmail.com) |
62258278 | 6 | * Internal BPF Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com |
0a14842f | 7 | */ |
0a14842f ED |
8 | #include <linux/netdevice.h> |
9 | #include <linux/filter.h> | |
855ddb56 | 10 | #include <linux/if_vlan.h> |
71d22d58 DB |
11 | #include <linux/bpf.h> |
12 | ||
d1163651 | 13 | #include <asm/set_memory.h> |
a493a87f | 14 | #include <asm/nospec-branch.h> |
0a14842f | 15 | |
5cccc702 | 16 | static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) |
0a14842f ED |
17 | { |
18 | if (len == 1) | |
19 | *ptr = bytes; | |
20 | else if (len == 2) | |
21 | *(u16 *)ptr = bytes; | |
22 | else { | |
23 | *(u32 *)ptr = bytes; | |
24 | barrier(); | |
25 | } | |
26 | return ptr + len; | |
27 | } | |
28 | ||
b52f00e6 AS |
29 | #define EMIT(bytes, len) \ |
30 | do { prog = emit_code(prog, bytes, len); cnt += len; } while (0) | |
0a14842f ED |
31 | |
32 | #define EMIT1(b1) EMIT(b1, 1) | |
33 | #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2) | |
34 | #define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3) | |
35 | #define EMIT4(b1, b2, b3, b4) EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4) | |
a2c7a983 | 36 | |
62258278 | 37 | #define EMIT1_off32(b1, off) \ |
a2c7a983 | 38 | do { EMIT1(b1); EMIT(off, 4); } while (0) |
62258278 | 39 | #define EMIT2_off32(b1, b2, off) \ |
a2c7a983 | 40 | do { EMIT2(b1, b2); EMIT(off, 4); } while (0) |
62258278 | 41 | #define EMIT3_off32(b1, b2, b3, off) \ |
a2c7a983 | 42 | do { EMIT3(b1, b2, b3); EMIT(off, 4); } while (0) |
62258278 | 43 | #define EMIT4_off32(b1, b2, b3, b4, off) \ |
a2c7a983 | 44 | do { EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0) |
0a14842f | 45 | |
5cccc702 | 46 | static bool is_imm8(int value) |
0a14842f ED |
47 | { |
48 | return value <= 127 && value >= -128; | |
49 | } | |
50 | ||
5cccc702 | 51 | static bool is_simm32(s64 value) |
0a14842f | 52 | { |
6fe8b9c1 DB |
53 | return value == (s64)(s32)value; |
54 | } | |
55 | ||
56 | static bool is_uimm32(u64 value) | |
57 | { | |
58 | return value == (u64)(u32)value; | |
0a14842f ED |
59 | } |
60 | ||
e430f34e | 61 | /* mov dst, src */ |
a2c7a983 IM |
62 | #define EMIT_mov(DST, SRC) \ |
63 | do { \ | |
64 | if (DST != SRC) \ | |
65 | EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \ | |
62258278 AS |
66 | } while (0) |
67 | ||
68 | static int bpf_size_to_x86_bytes(int bpf_size) | |
69 | { | |
70 | if (bpf_size == BPF_W) | |
71 | return 4; | |
72 | else if (bpf_size == BPF_H) | |
73 | return 2; | |
74 | else if (bpf_size == BPF_B) | |
75 | return 1; | |
76 | else if (bpf_size == BPF_DW) | |
77 | return 4; /* imm32 */ | |
78 | else | |
79 | return 0; | |
80 | } | |
0a14842f | 81 | |
a2c7a983 IM |
82 | /* |
83 | * List of x86 cond jumps opcodes (. + s8) | |
0a14842f ED |
84 | * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32) |
85 | */ | |
86 | #define X86_JB 0x72 | |
87 | #define X86_JAE 0x73 | |
88 | #define X86_JE 0x74 | |
89 | #define X86_JNE 0x75 | |
90 | #define X86_JBE 0x76 | |
91 | #define X86_JA 0x77 | |
52afc51e | 92 | #define X86_JL 0x7C |
62258278 | 93 | #define X86_JGE 0x7D |
52afc51e | 94 | #define X86_JLE 0x7E |
62258278 | 95 | #define X86_JG 0x7F |
0a14842f | 96 | |
a2c7a983 | 97 | /* Pick a register outside of BPF range for JIT internal work */ |
959a7579 | 98 | #define AUX_REG (MAX_BPF_JIT_REG + 1) |
62258278 | 99 | |
a2c7a983 IM |
100 | /* |
101 | * The following table maps BPF registers to x86-64 registers. | |
959a7579 | 102 | * |
a2c7a983 | 103 | * x86-64 register R12 is unused, since if used as base address |
959a7579 DB |
104 | * register in load/store instructions, it always needs an |
105 | * extra byte of encoding and is callee saved. | |
106 | * | |
e782bdcf DB |
107 | * Also x86-64 register R9 is unused. x86-64 register R10 is |
108 | * used for blinding (if enabled). | |
62258278 AS |
109 | */ |
110 | static const int reg2hex[] = { | |
a2c7a983 IM |
111 | [BPF_REG_0] = 0, /* RAX */ |
112 | [BPF_REG_1] = 7, /* RDI */ | |
113 | [BPF_REG_2] = 6, /* RSI */ | |
114 | [BPF_REG_3] = 2, /* RDX */ | |
115 | [BPF_REG_4] = 1, /* RCX */ | |
116 | [BPF_REG_5] = 0, /* R8 */ | |
117 | [BPF_REG_6] = 3, /* RBX callee saved */ | |
118 | [BPF_REG_7] = 5, /* R13 callee saved */ | |
119 | [BPF_REG_8] = 6, /* R14 callee saved */ | |
120 | [BPF_REG_9] = 7, /* R15 callee saved */ | |
121 | [BPF_REG_FP] = 5, /* RBP readonly */ | |
122 | [BPF_REG_AX] = 2, /* R10 temp register */ | |
123 | [AUX_REG] = 3, /* R11 temp register */ | |
62258278 AS |
124 | }; |
125 | ||
a2c7a983 IM |
126 | /* |
127 | * is_ereg() == true if BPF register 'reg' maps to x86-64 r8..r15 | |
62258278 AS |
128 | * which need extra byte of encoding. |
129 | * rax,rcx,...,rbp have simpler encoding | |
130 | */ | |
5cccc702 | 131 | static bool is_ereg(u32 reg) |
62258278 | 132 | { |
d148134b JP |
133 | return (1 << reg) & (BIT(BPF_REG_5) | |
134 | BIT(AUX_REG) | | |
135 | BIT(BPF_REG_7) | | |
136 | BIT(BPF_REG_8) | | |
959a7579 DB |
137 | BIT(BPF_REG_9) | |
138 | BIT(BPF_REG_AX)); | |
62258278 AS |
139 | } |
140 | ||
de0a444d DB |
141 | static bool is_axreg(u32 reg) |
142 | { | |
143 | return reg == BPF_REG_0; | |
144 | } | |
145 | ||
a2c7a983 | 146 | /* Add modifiers if 'reg' maps to x86-64 registers R8..R15 */ |
5cccc702 | 147 | static u8 add_1mod(u8 byte, u32 reg) |
62258278 AS |
148 | { |
149 | if (is_ereg(reg)) | |
150 | byte |= 1; | |
151 | return byte; | |
152 | } | |
153 | ||
5cccc702 | 154 | static u8 add_2mod(u8 byte, u32 r1, u32 r2) |
62258278 AS |
155 | { |
156 | if (is_ereg(r1)) | |
157 | byte |= 1; | |
158 | if (is_ereg(r2)) | |
159 | byte |= 4; | |
160 | return byte; | |
161 | } | |
162 | ||
a2c7a983 | 163 | /* Encode 'dst_reg' register into x86-64 opcode 'byte' */ |
5cccc702 | 164 | static u8 add_1reg(u8 byte, u32 dst_reg) |
62258278 | 165 | { |
e430f34e | 166 | return byte + reg2hex[dst_reg]; |
62258278 AS |
167 | } |
168 | ||
a2c7a983 | 169 | /* Encode 'dst_reg' and 'src_reg' registers into x86-64 opcode 'byte' */ |
5cccc702 | 170 | static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg) |
62258278 | 171 | { |
e430f34e | 172 | return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3); |
62258278 AS |
173 | } |
174 | ||
738cbe72 DB |
175 | static void jit_fill_hole(void *area, unsigned int size) |
176 | { | |
a2c7a983 | 177 | /* Fill whole space with INT3 instructions */ |
738cbe72 DB |
178 | memset(area, 0xcc, size); |
179 | } | |
180 | ||
f3c2af7b | 181 | struct jit_context { |
a2c7a983 | 182 | int cleanup_addr; /* Epilogue code offset */ |
f3c2af7b AS |
183 | }; |
184 | ||
a2c7a983 | 185 | /* Maximum number of bytes emitted while JITing one eBPF insn */ |
e0ee9c12 AS |
186 | #define BPF_MAX_INSN_SIZE 128 |
187 | #define BPF_INSN_SAFETY 64 | |
188 | ||
fe8d9571 | 189 | #define PROLOGUE_SIZE 20 |
b52f00e6 | 190 | |
a2c7a983 IM |
191 | /* |
192 | * Emit x86-64 prologue code for BPF program and check its size. | |
b52f00e6 AS |
193 | * bpf_tail_call helper will skip it while jumping into another program |
194 | */ | |
08691752 | 195 | static void emit_prologue(u8 **pprog, u32 stack_depth, bool ebpf_from_cbpf) |
0a14842f | 196 | { |
b52f00e6 AS |
197 | u8 *prog = *pprog; |
198 | int cnt = 0; | |
0a14842f | 199 | |
fe8d9571 AS |
200 | EMIT1(0x55); /* push rbp */ |
201 | EMIT3(0x48, 0x89, 0xE5); /* mov rbp, rsp */ | |
202 | /* sub rsp, rounded_stack_depth */ | |
203 | EMIT3_off32(0x48, 0x81, 0xEC, round_up(stack_depth, 8)); | |
204 | EMIT1(0x53); /* push rbx */ | |
205 | EMIT2(0x41, 0x55); /* push r13 */ | |
206 | EMIT2(0x41, 0x56); /* push r14 */ | |
207 | EMIT2(0x41, 0x57); /* push r15 */ | |
08691752 | 208 | if (!ebpf_from_cbpf) { |
fe8d9571 AS |
209 | /* zero init tail_call_cnt */ |
210 | EMIT2(0x6a, 0x00); | |
08691752 DB |
211 | BUILD_BUG_ON(cnt != PROLOGUE_SIZE); |
212 | } | |
b52f00e6 AS |
213 | *pprog = prog; |
214 | } | |
215 | ||
a2c7a983 IM |
216 | /* |
217 | * Generate the following code: | |
218 | * | |
b52f00e6 AS |
219 | * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ... |
220 | * if (index >= array->map.max_entries) | |
221 | * goto out; | |
222 | * if (++tail_call_cnt > MAX_TAIL_CALL_CNT) | |
223 | * goto out; | |
2a36f0b9 | 224 | * prog = array->ptrs[index]; |
b52f00e6 AS |
225 | * if (prog == NULL) |
226 | * goto out; | |
227 | * goto *(prog->bpf_func + prologue_size); | |
228 | * out: | |
229 | */ | |
230 | static void emit_bpf_tail_call(u8 **pprog) | |
231 | { | |
232 | u8 *prog = *pprog; | |
233 | int label1, label2, label3; | |
234 | int cnt = 0; | |
235 | ||
a2c7a983 IM |
236 | /* |
237 | * rdi - pointer to ctx | |
b52f00e6 AS |
238 | * rsi - pointer to bpf_array |
239 | * rdx - index in bpf_array | |
240 | */ | |
241 | ||
a2c7a983 IM |
242 | /* |
243 | * if (index >= array->map.max_entries) | |
244 | * goto out; | |
b52f00e6 | 245 | */ |
90caccdd AS |
246 | EMIT2(0x89, 0xD2); /* mov edx, edx */ |
247 | EMIT3(0x39, 0x56, /* cmp dword ptr [rsi + 16], edx */ | |
b52f00e6 | 248 | offsetof(struct bpf_array, map.max_entries)); |
a2c7a983 | 249 | #define OFFSET1 (41 + RETPOLINE_RAX_BPF_JIT_SIZE) /* Number of bytes to jump */ |
b52f00e6 AS |
250 | EMIT2(X86_JBE, OFFSET1); /* jbe out */ |
251 | label1 = cnt; | |
252 | ||
a2c7a983 IM |
253 | /* |
254 | * if (tail_call_cnt > MAX_TAIL_CALL_CNT) | |
255 | * goto out; | |
b52f00e6 | 256 | */ |
fe8d9571 | 257 | EMIT2_off32(0x8B, 0x85, -36 - MAX_BPF_STACK); /* mov eax, dword ptr [rbp - 548] */ |
b52f00e6 | 258 | EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT); /* cmp eax, MAX_TAIL_CALL_CNT */ |
a493a87f | 259 | #define OFFSET2 (30 + RETPOLINE_RAX_BPF_JIT_SIZE) |
b52f00e6 AS |
260 | EMIT2(X86_JA, OFFSET2); /* ja out */ |
261 | label2 = cnt; | |
262 | EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */ | |
fe8d9571 | 263 | EMIT2_off32(0x89, 0x85, -36 - MAX_BPF_STACK); /* mov dword ptr [rbp -548], eax */ |
b52f00e6 | 264 | |
2a36f0b9 | 265 | /* prog = array->ptrs[index]; */ |
84ccac6e | 266 | EMIT4_off32(0x48, 0x8B, 0x84, 0xD6, /* mov rax, [rsi + rdx * 8 + offsetof(...)] */ |
2a36f0b9 | 267 | offsetof(struct bpf_array, ptrs)); |
b52f00e6 | 268 | |
a2c7a983 IM |
269 | /* |
270 | * if (prog == NULL) | |
271 | * goto out; | |
b52f00e6 | 272 | */ |
84ccac6e | 273 | EMIT3(0x48, 0x85, 0xC0); /* test rax,rax */ |
a493a87f | 274 | #define OFFSET3 (8 + RETPOLINE_RAX_BPF_JIT_SIZE) |
b52f00e6 AS |
275 | EMIT2(X86_JE, OFFSET3); /* je out */ |
276 | label3 = cnt; | |
277 | ||
278 | /* goto *(prog->bpf_func + prologue_size); */ | |
279 | EMIT4(0x48, 0x8B, 0x40, /* mov rax, qword ptr [rax + 32] */ | |
280 | offsetof(struct bpf_prog, bpf_func)); | |
281 | EMIT4(0x48, 0x83, 0xC0, PROLOGUE_SIZE); /* add rax, prologue_size */ | |
282 | ||
a2c7a983 IM |
283 | /* |
284 | * Wow we're ready to jump into next BPF program | |
b52f00e6 AS |
285 | * rdi == ctx (1st arg) |
286 | * rax == prog->bpf_func + prologue_size | |
287 | */ | |
a493a87f | 288 | RETPOLINE_RAX_BPF_JIT(); |
b52f00e6 AS |
289 | |
290 | /* out: */ | |
291 | BUILD_BUG_ON(cnt - label1 != OFFSET1); | |
292 | BUILD_BUG_ON(cnt - label2 != OFFSET2); | |
293 | BUILD_BUG_ON(cnt - label3 != OFFSET3); | |
294 | *pprog = prog; | |
295 | } | |
296 | ||
6fe8b9c1 DB |
297 | static void emit_mov_imm32(u8 **pprog, bool sign_propagate, |
298 | u32 dst_reg, const u32 imm32) | |
299 | { | |
300 | u8 *prog = *pprog; | |
301 | u8 b1, b2, b3; | |
302 | int cnt = 0; | |
303 | ||
a2c7a983 IM |
304 | /* |
305 | * Optimization: if imm32 is positive, use 'mov %eax, imm32' | |
6fe8b9c1 DB |
306 | * (which zero-extends imm32) to save 2 bytes. |
307 | */ | |
308 | if (sign_propagate && (s32)imm32 < 0) { | |
309 | /* 'mov %rax, imm32' sign extends imm32 */ | |
310 | b1 = add_1mod(0x48, dst_reg); | |
311 | b2 = 0xC7; | |
312 | b3 = 0xC0; | |
313 | EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32); | |
314 | goto done; | |
315 | } | |
316 | ||
a2c7a983 IM |
317 | /* |
318 | * Optimization: if imm32 is zero, use 'xor %eax, %eax' | |
6fe8b9c1 DB |
319 | * to save 3 bytes. |
320 | */ | |
321 | if (imm32 == 0) { | |
322 | if (is_ereg(dst_reg)) | |
323 | EMIT1(add_2mod(0x40, dst_reg, dst_reg)); | |
324 | b2 = 0x31; /* xor */ | |
325 | b3 = 0xC0; | |
326 | EMIT2(b2, add_2reg(b3, dst_reg, dst_reg)); | |
327 | goto done; | |
328 | } | |
329 | ||
330 | /* mov %eax, imm32 */ | |
331 | if (is_ereg(dst_reg)) | |
332 | EMIT1(add_1mod(0x40, dst_reg)); | |
333 | EMIT1_off32(add_1reg(0xB8, dst_reg), imm32); | |
334 | done: | |
335 | *pprog = prog; | |
336 | } | |
337 | ||
338 | static void emit_mov_imm64(u8 **pprog, u32 dst_reg, | |
339 | const u32 imm32_hi, const u32 imm32_lo) | |
340 | { | |
341 | u8 *prog = *pprog; | |
342 | int cnt = 0; | |
343 | ||
344 | if (is_uimm32(((u64)imm32_hi << 32) | (u32)imm32_lo)) { | |
a2c7a983 IM |
345 | /* |
346 | * For emitting plain u32, where sign bit must not be | |
6fe8b9c1 DB |
347 | * propagated LLVM tends to load imm64 over mov32 |
348 | * directly, so save couple of bytes by just doing | |
349 | * 'mov %eax, imm32' instead. | |
350 | */ | |
351 | emit_mov_imm32(&prog, false, dst_reg, imm32_lo); | |
352 | } else { | |
353 | /* movabsq %rax, imm64 */ | |
354 | EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg)); | |
355 | EMIT(imm32_lo, 4); | |
356 | EMIT(imm32_hi, 4); | |
357 | } | |
358 | ||
359 | *pprog = prog; | |
360 | } | |
361 | ||
4c38e2f3 DB |
362 | static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg) |
363 | { | |
364 | u8 *prog = *pprog; | |
365 | int cnt = 0; | |
366 | ||
367 | if (is64) { | |
368 | /* mov dst, src */ | |
369 | EMIT_mov(dst_reg, src_reg); | |
370 | } else { | |
371 | /* mov32 dst, src */ | |
372 | if (is_ereg(dst_reg) || is_ereg(src_reg)) | |
373 | EMIT1(add_2mod(0x40, dst_reg, src_reg)); | |
374 | EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg)); | |
375 | } | |
376 | ||
377 | *pprog = prog; | |
378 | } | |
379 | ||
b52f00e6 AS |
380 | static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, |
381 | int oldproglen, struct jit_context *ctx) | |
382 | { | |
383 | struct bpf_insn *insn = bpf_prog->insnsi; | |
384 | int insn_cnt = bpf_prog->len; | |
b52f00e6 AS |
385 | bool seen_exit = false; |
386 | u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY]; | |
387 | int i, cnt = 0; | |
388 | int proglen = 0; | |
389 | u8 *prog = temp; | |
390 | ||
08691752 DB |
391 | emit_prologue(&prog, bpf_prog->aux->stack_depth, |
392 | bpf_prog_was_classic(bpf_prog)); | |
7c2e988f | 393 | addrs[0] = prog - temp; |
b52f00e6 | 394 | |
7c2e988f | 395 | for (i = 1; i <= insn_cnt; i++, insn++) { |
e430f34e AS |
396 | const s32 imm32 = insn->imm; |
397 | u32 dst_reg = insn->dst_reg; | |
398 | u32 src_reg = insn->src_reg; | |
6fe8b9c1 | 399 | u8 b2 = 0, b3 = 0; |
62258278 AS |
400 | s64 jmp_offset; |
401 | u8 jmp_cond; | |
402 | int ilen; | |
403 | u8 *func; | |
404 | ||
405 | switch (insn->code) { | |
406 | /* ALU */ | |
407 | case BPF_ALU | BPF_ADD | BPF_X: | |
408 | case BPF_ALU | BPF_SUB | BPF_X: | |
409 | case BPF_ALU | BPF_AND | BPF_X: | |
410 | case BPF_ALU | BPF_OR | BPF_X: | |
411 | case BPF_ALU | BPF_XOR | BPF_X: | |
412 | case BPF_ALU64 | BPF_ADD | BPF_X: | |
413 | case BPF_ALU64 | BPF_SUB | BPF_X: | |
414 | case BPF_ALU64 | BPF_AND | BPF_X: | |
415 | case BPF_ALU64 | BPF_OR | BPF_X: | |
416 | case BPF_ALU64 | BPF_XOR | BPF_X: | |
417 | switch (BPF_OP(insn->code)) { | |
418 | case BPF_ADD: b2 = 0x01; break; | |
419 | case BPF_SUB: b2 = 0x29; break; | |
420 | case BPF_AND: b2 = 0x21; break; | |
421 | case BPF_OR: b2 = 0x09; break; | |
422 | case BPF_XOR: b2 = 0x31; break; | |
0a14842f | 423 | } |
62258278 | 424 | if (BPF_CLASS(insn->code) == BPF_ALU64) |
e430f34e AS |
425 | EMIT1(add_2mod(0x48, dst_reg, src_reg)); |
426 | else if (is_ereg(dst_reg) || is_ereg(src_reg)) | |
427 | EMIT1(add_2mod(0x40, dst_reg, src_reg)); | |
428 | EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg)); | |
62258278 | 429 | break; |
0a14842f | 430 | |
62258278 | 431 | case BPF_ALU64 | BPF_MOV | BPF_X: |
62258278 | 432 | case BPF_ALU | BPF_MOV | BPF_X: |
4c38e2f3 DB |
433 | emit_mov_reg(&prog, |
434 | BPF_CLASS(insn->code) == BPF_ALU64, | |
435 | dst_reg, src_reg); | |
62258278 | 436 | break; |
0a14842f | 437 | |
e430f34e | 438 | /* neg dst */ |
62258278 AS |
439 | case BPF_ALU | BPF_NEG: |
440 | case BPF_ALU64 | BPF_NEG: | |
441 | if (BPF_CLASS(insn->code) == BPF_ALU64) | |
e430f34e AS |
442 | EMIT1(add_1mod(0x48, dst_reg)); |
443 | else if (is_ereg(dst_reg)) | |
444 | EMIT1(add_1mod(0x40, dst_reg)); | |
445 | EMIT2(0xF7, add_1reg(0xD8, dst_reg)); | |
62258278 AS |
446 | break; |
447 | ||
448 | case BPF_ALU | BPF_ADD | BPF_K: | |
449 | case BPF_ALU | BPF_SUB | BPF_K: | |
450 | case BPF_ALU | BPF_AND | BPF_K: | |
451 | case BPF_ALU | BPF_OR | BPF_K: | |
452 | case BPF_ALU | BPF_XOR | BPF_K: | |
453 | case BPF_ALU64 | BPF_ADD | BPF_K: | |
454 | case BPF_ALU64 | BPF_SUB | BPF_K: | |
455 | case BPF_ALU64 | BPF_AND | BPF_K: | |
456 | case BPF_ALU64 | BPF_OR | BPF_K: | |
457 | case BPF_ALU64 | BPF_XOR | BPF_K: | |
458 | if (BPF_CLASS(insn->code) == BPF_ALU64) | |
e430f34e AS |
459 | EMIT1(add_1mod(0x48, dst_reg)); |
460 | else if (is_ereg(dst_reg)) | |
461 | EMIT1(add_1mod(0x40, dst_reg)); | |
62258278 | 462 | |
a2c7a983 IM |
463 | /* |
464 | * b3 holds 'normal' opcode, b2 short form only valid | |
de0a444d DB |
465 | * in case dst is eax/rax. |
466 | */ | |
62258278 | 467 | switch (BPF_OP(insn->code)) { |
de0a444d DB |
468 | case BPF_ADD: |
469 | b3 = 0xC0; | |
470 | b2 = 0x05; | |
471 | break; | |
472 | case BPF_SUB: | |
473 | b3 = 0xE8; | |
474 | b2 = 0x2D; | |
475 | break; | |
476 | case BPF_AND: | |
477 | b3 = 0xE0; | |
478 | b2 = 0x25; | |
479 | break; | |
480 | case BPF_OR: | |
481 | b3 = 0xC8; | |
482 | b2 = 0x0D; | |
483 | break; | |
484 | case BPF_XOR: | |
485 | b3 = 0xF0; | |
486 | b2 = 0x35; | |
487 | break; | |
62258278 AS |
488 | } |
489 | ||
e430f34e AS |
490 | if (is_imm8(imm32)) |
491 | EMIT3(0x83, add_1reg(b3, dst_reg), imm32); | |
de0a444d DB |
492 | else if (is_axreg(dst_reg)) |
493 | EMIT1_off32(b2, imm32); | |
62258278 | 494 | else |
e430f34e | 495 | EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32); |
62258278 AS |
496 | break; |
497 | ||
498 | case BPF_ALU64 | BPF_MOV | BPF_K: | |
62258278 | 499 | case BPF_ALU | BPF_MOV | BPF_K: |
6fe8b9c1 DB |
500 | emit_mov_imm32(&prog, BPF_CLASS(insn->code) == BPF_ALU64, |
501 | dst_reg, imm32); | |
62258278 AS |
502 | break; |
503 | ||
02ab695b | 504 | case BPF_LD | BPF_IMM | BPF_DW: |
6fe8b9c1 | 505 | emit_mov_imm64(&prog, dst_reg, insn[1].imm, insn[0].imm); |
02ab695b AS |
506 | insn++; |
507 | i++; | |
508 | break; | |
509 | ||
e430f34e | 510 | /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */ |
62258278 AS |
511 | case BPF_ALU | BPF_MOD | BPF_X: |
512 | case BPF_ALU | BPF_DIV | BPF_X: | |
513 | case BPF_ALU | BPF_MOD | BPF_K: | |
514 | case BPF_ALU | BPF_DIV | BPF_K: | |
515 | case BPF_ALU64 | BPF_MOD | BPF_X: | |
516 | case BPF_ALU64 | BPF_DIV | BPF_X: | |
517 | case BPF_ALU64 | BPF_MOD | BPF_K: | |
518 | case BPF_ALU64 | BPF_DIV | BPF_K: | |
519 | EMIT1(0x50); /* push rax */ | |
520 | EMIT1(0x52); /* push rdx */ | |
521 | ||
522 | if (BPF_SRC(insn->code) == BPF_X) | |
e430f34e AS |
523 | /* mov r11, src_reg */ |
524 | EMIT_mov(AUX_REG, src_reg); | |
62258278 | 525 | else |
e430f34e AS |
526 | /* mov r11, imm32 */ |
527 | EMIT3_off32(0x49, 0xC7, 0xC3, imm32); | |
62258278 | 528 | |
e430f34e AS |
529 | /* mov rax, dst_reg */ |
530 | EMIT_mov(BPF_REG_0, dst_reg); | |
62258278 | 531 | |
a2c7a983 IM |
532 | /* |
533 | * xor edx, edx | |
62258278 AS |
534 | * equivalent to 'xor rdx, rdx', but one byte less |
535 | */ | |
536 | EMIT2(0x31, 0xd2); | |
537 | ||
62258278 AS |
538 | if (BPF_CLASS(insn->code) == BPF_ALU64) |
539 | /* div r11 */ | |
540 | EMIT3(0x49, 0xF7, 0xF3); | |
541 | else | |
542 | /* div r11d */ | |
543 | EMIT3(0x41, 0xF7, 0xF3); | |
544 | ||
545 | if (BPF_OP(insn->code) == BPF_MOD) | |
546 | /* mov r11, rdx */ | |
547 | EMIT3(0x49, 0x89, 0xD3); | |
548 | else | |
549 | /* mov r11, rax */ | |
550 | EMIT3(0x49, 0x89, 0xC3); | |
551 | ||
552 | EMIT1(0x5A); /* pop rdx */ | |
553 | EMIT1(0x58); /* pop rax */ | |
554 | ||
e430f34e AS |
555 | /* mov dst_reg, r11 */ |
556 | EMIT_mov(dst_reg, AUX_REG); | |
62258278 AS |
557 | break; |
558 | ||
559 | case BPF_ALU | BPF_MUL | BPF_K: | |
560 | case BPF_ALU | BPF_MUL | BPF_X: | |
561 | case BPF_ALU64 | BPF_MUL | BPF_K: | |
562 | case BPF_ALU64 | BPF_MUL | BPF_X: | |
4c38e2f3 DB |
563 | { |
564 | bool is64 = BPF_CLASS(insn->code) == BPF_ALU64; | |
565 | ||
d806a0cf DB |
566 | if (dst_reg != BPF_REG_0) |
567 | EMIT1(0x50); /* push rax */ | |
568 | if (dst_reg != BPF_REG_3) | |
569 | EMIT1(0x52); /* push rdx */ | |
62258278 | 570 | |
e430f34e AS |
571 | /* mov r11, dst_reg */ |
572 | EMIT_mov(AUX_REG, dst_reg); | |
62258278 AS |
573 | |
574 | if (BPF_SRC(insn->code) == BPF_X) | |
4c38e2f3 | 575 | emit_mov_reg(&prog, is64, BPF_REG_0, src_reg); |
62258278 | 576 | else |
4c38e2f3 | 577 | emit_mov_imm32(&prog, is64, BPF_REG_0, imm32); |
62258278 | 578 | |
4c38e2f3 | 579 | if (is64) |
62258278 AS |
580 | EMIT1(add_1mod(0x48, AUX_REG)); |
581 | else if (is_ereg(AUX_REG)) | |
582 | EMIT1(add_1mod(0x40, AUX_REG)); | |
583 | /* mul(q) r11 */ | |
584 | EMIT2(0xF7, add_1reg(0xE0, AUX_REG)); | |
585 | ||
d806a0cf DB |
586 | if (dst_reg != BPF_REG_3) |
587 | EMIT1(0x5A); /* pop rdx */ | |
588 | if (dst_reg != BPF_REG_0) { | |
589 | /* mov dst_reg, rax */ | |
590 | EMIT_mov(dst_reg, BPF_REG_0); | |
591 | EMIT1(0x58); /* pop rax */ | |
592 | } | |
62258278 | 593 | break; |
4c38e2f3 | 594 | } |
a2c7a983 | 595 | /* Shifts */ |
62258278 AS |
596 | case BPF_ALU | BPF_LSH | BPF_K: |
597 | case BPF_ALU | BPF_RSH | BPF_K: | |
598 | case BPF_ALU | BPF_ARSH | BPF_K: | |
599 | case BPF_ALU64 | BPF_LSH | BPF_K: | |
600 | case BPF_ALU64 | BPF_RSH | BPF_K: | |
601 | case BPF_ALU64 | BPF_ARSH | BPF_K: | |
602 | if (BPF_CLASS(insn->code) == BPF_ALU64) | |
e430f34e AS |
603 | EMIT1(add_1mod(0x48, dst_reg)); |
604 | else if (is_ereg(dst_reg)) | |
605 | EMIT1(add_1mod(0x40, dst_reg)); | |
62258278 AS |
606 | |
607 | switch (BPF_OP(insn->code)) { | |
608 | case BPF_LSH: b3 = 0xE0; break; | |
609 | case BPF_RSH: b3 = 0xE8; break; | |
610 | case BPF_ARSH: b3 = 0xF8; break; | |
611 | } | |
88e69a1f DB |
612 | |
613 | if (imm32 == 1) | |
614 | EMIT2(0xD1, add_1reg(b3, dst_reg)); | |
615 | else | |
616 | EMIT3(0xC1, add_1reg(b3, dst_reg), imm32); | |
62258278 AS |
617 | break; |
618 | ||
72b603ee AS |
619 | case BPF_ALU | BPF_LSH | BPF_X: |
620 | case BPF_ALU | BPF_RSH | BPF_X: | |
621 | case BPF_ALU | BPF_ARSH | BPF_X: | |
622 | case BPF_ALU64 | BPF_LSH | BPF_X: | |
623 | case BPF_ALU64 | BPF_RSH | BPF_X: | |
624 | case BPF_ALU64 | BPF_ARSH | BPF_X: | |
625 | ||
a2c7a983 | 626 | /* Check for bad case when dst_reg == rcx */ |
72b603ee AS |
627 | if (dst_reg == BPF_REG_4) { |
628 | /* mov r11, dst_reg */ | |
629 | EMIT_mov(AUX_REG, dst_reg); | |
630 | dst_reg = AUX_REG; | |
631 | } | |
632 | ||
633 | if (src_reg != BPF_REG_4) { /* common case */ | |
634 | EMIT1(0x51); /* push rcx */ | |
635 | ||
636 | /* mov rcx, src_reg */ | |
637 | EMIT_mov(BPF_REG_4, src_reg); | |
638 | } | |
639 | ||
640 | /* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */ | |
641 | if (BPF_CLASS(insn->code) == BPF_ALU64) | |
642 | EMIT1(add_1mod(0x48, dst_reg)); | |
643 | else if (is_ereg(dst_reg)) | |
644 | EMIT1(add_1mod(0x40, dst_reg)); | |
645 | ||
646 | switch (BPF_OP(insn->code)) { | |
647 | case BPF_LSH: b3 = 0xE0; break; | |
648 | case BPF_RSH: b3 = 0xE8; break; | |
649 | case BPF_ARSH: b3 = 0xF8; break; | |
650 | } | |
651 | EMIT2(0xD3, add_1reg(b3, dst_reg)); | |
652 | ||
653 | if (src_reg != BPF_REG_4) | |
654 | EMIT1(0x59); /* pop rcx */ | |
655 | ||
656 | if (insn->dst_reg == BPF_REG_4) | |
657 | /* mov dst_reg, r11 */ | |
658 | EMIT_mov(insn->dst_reg, AUX_REG); | |
659 | break; | |
660 | ||
62258278 | 661 | case BPF_ALU | BPF_END | BPF_FROM_BE: |
e430f34e | 662 | switch (imm32) { |
62258278 | 663 | case 16: |
a2c7a983 | 664 | /* Emit 'ror %ax, 8' to swap lower 2 bytes */ |
62258278 | 665 | EMIT1(0x66); |
e430f34e | 666 | if (is_ereg(dst_reg)) |
62258278 | 667 | EMIT1(0x41); |
e430f34e | 668 | EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8); |
343f845b | 669 | |
a2c7a983 | 670 | /* Emit 'movzwl eax, ax' */ |
343f845b AS |
671 | if (is_ereg(dst_reg)) |
672 | EMIT3(0x45, 0x0F, 0xB7); | |
673 | else | |
674 | EMIT2(0x0F, 0xB7); | |
675 | EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); | |
62258278 AS |
676 | break; |
677 | case 32: | |
a2c7a983 | 678 | /* Emit 'bswap eax' to swap lower 4 bytes */ |
e430f34e | 679 | if (is_ereg(dst_reg)) |
62258278 | 680 | EMIT2(0x41, 0x0F); |
0a14842f | 681 | else |
62258278 | 682 | EMIT1(0x0F); |
e430f34e | 683 | EMIT1(add_1reg(0xC8, dst_reg)); |
0a14842f | 684 | break; |
62258278 | 685 | case 64: |
a2c7a983 | 686 | /* Emit 'bswap rax' to swap 8 bytes */ |
e430f34e AS |
687 | EMIT3(add_1mod(0x48, dst_reg), 0x0F, |
688 | add_1reg(0xC8, dst_reg)); | |
3b58908a ED |
689 | break; |
690 | } | |
62258278 AS |
691 | break; |
692 | ||
693 | case BPF_ALU | BPF_END | BPF_FROM_LE: | |
343f845b AS |
694 | switch (imm32) { |
695 | case 16: | |
a2c7a983 IM |
696 | /* |
697 | * Emit 'movzwl eax, ax' to zero extend 16-bit | |
343f845b AS |
698 | * into 64 bit |
699 | */ | |
700 | if (is_ereg(dst_reg)) | |
701 | EMIT3(0x45, 0x0F, 0xB7); | |
702 | else | |
703 | EMIT2(0x0F, 0xB7); | |
704 | EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); | |
705 | break; | |
706 | case 32: | |
a2c7a983 | 707 | /* Emit 'mov eax, eax' to clear upper 32-bits */ |
343f845b AS |
708 | if (is_ereg(dst_reg)) |
709 | EMIT1(0x45); | |
710 | EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg)); | |
711 | break; | |
712 | case 64: | |
713 | /* nop */ | |
714 | break; | |
715 | } | |
62258278 AS |
716 | break; |
717 | ||
e430f34e | 718 | /* ST: *(u8*)(dst_reg + off) = imm */ |
62258278 | 719 | case BPF_ST | BPF_MEM | BPF_B: |
e430f34e | 720 | if (is_ereg(dst_reg)) |
62258278 AS |
721 | EMIT2(0x41, 0xC6); |
722 | else | |
723 | EMIT1(0xC6); | |
724 | goto st; | |
725 | case BPF_ST | BPF_MEM | BPF_H: | |
e430f34e | 726 | if (is_ereg(dst_reg)) |
62258278 AS |
727 | EMIT3(0x66, 0x41, 0xC7); |
728 | else | |
729 | EMIT2(0x66, 0xC7); | |
730 | goto st; | |
731 | case BPF_ST | BPF_MEM | BPF_W: | |
e430f34e | 732 | if (is_ereg(dst_reg)) |
62258278 AS |
733 | EMIT2(0x41, 0xC7); |
734 | else | |
735 | EMIT1(0xC7); | |
736 | goto st; | |
737 | case BPF_ST | BPF_MEM | BPF_DW: | |
e430f34e | 738 | EMIT2(add_1mod(0x48, dst_reg), 0xC7); |
62258278 AS |
739 | |
740 | st: if (is_imm8(insn->off)) | |
e430f34e | 741 | EMIT2(add_1reg(0x40, dst_reg), insn->off); |
62258278 | 742 | else |
e430f34e | 743 | EMIT1_off32(add_1reg(0x80, dst_reg), insn->off); |
62258278 | 744 | |
e430f34e | 745 | EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code))); |
62258278 AS |
746 | break; |
747 | ||
e430f34e | 748 | /* STX: *(u8*)(dst_reg + off) = src_reg */ |
62258278 | 749 | case BPF_STX | BPF_MEM | BPF_B: |
a2c7a983 | 750 | /* Emit 'mov byte ptr [rax + off], al' */ |
e430f34e | 751 | if (is_ereg(dst_reg) || is_ereg(src_reg) || |
a2c7a983 | 752 | /* We have to add extra byte for x86 SIL, DIL regs */ |
e430f34e AS |
753 | src_reg == BPF_REG_1 || src_reg == BPF_REG_2) |
754 | EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88); | |
62258278 AS |
755 | else |
756 | EMIT1(0x88); | |
757 | goto stx; | |
758 | case BPF_STX | BPF_MEM | BPF_H: | |
e430f34e AS |
759 | if (is_ereg(dst_reg) || is_ereg(src_reg)) |
760 | EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89); | |
62258278 AS |
761 | else |
762 | EMIT2(0x66, 0x89); | |
763 | goto stx; | |
764 | case BPF_STX | BPF_MEM | BPF_W: | |
e430f34e AS |
765 | if (is_ereg(dst_reg) || is_ereg(src_reg)) |
766 | EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89); | |
62258278 AS |
767 | else |
768 | EMIT1(0x89); | |
769 | goto stx; | |
770 | case BPF_STX | BPF_MEM | BPF_DW: | |
e430f34e | 771 | EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89); |
62258278 | 772 | stx: if (is_imm8(insn->off)) |
e430f34e | 773 | EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); |
62258278 | 774 | else |
e430f34e | 775 | EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), |
62258278 AS |
776 | insn->off); |
777 | break; | |
778 | ||
e430f34e | 779 | /* LDX: dst_reg = *(u8*)(src_reg + off) */ |
62258278 | 780 | case BPF_LDX | BPF_MEM | BPF_B: |
a2c7a983 | 781 | /* Emit 'movzx rax, byte ptr [rax + off]' */ |
e430f34e | 782 | EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6); |
62258278 AS |
783 | goto ldx; |
784 | case BPF_LDX | BPF_MEM | BPF_H: | |
a2c7a983 | 785 | /* Emit 'movzx rax, word ptr [rax + off]' */ |
e430f34e | 786 | EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7); |
62258278 AS |
787 | goto ldx; |
788 | case BPF_LDX | BPF_MEM | BPF_W: | |
a2c7a983 | 789 | /* Emit 'mov eax, dword ptr [rax+0x14]' */ |
e430f34e AS |
790 | if (is_ereg(dst_reg) || is_ereg(src_reg)) |
791 | EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B); | |
62258278 AS |
792 | else |
793 | EMIT1(0x8B); | |
794 | goto ldx; | |
795 | case BPF_LDX | BPF_MEM | BPF_DW: | |
a2c7a983 | 796 | /* Emit 'mov rax, qword ptr [rax+0x14]' */ |
e430f34e | 797 | EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B); |
a2c7a983 IM |
798 | ldx: /* |
799 | * If insn->off == 0 we can save one extra byte, but | |
800 | * special case of x86 R13 which always needs an offset | |
62258278 AS |
801 | * is not worth the hassle |
802 | */ | |
803 | if (is_imm8(insn->off)) | |
e430f34e | 804 | EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off); |
62258278 | 805 | else |
e430f34e | 806 | EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), |
62258278 AS |
807 | insn->off); |
808 | break; | |
809 | ||
e430f34e | 810 | /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */ |
62258278 | 811 | case BPF_STX | BPF_XADD | BPF_W: |
a2c7a983 | 812 | /* Emit 'lock add dword ptr [rax + off], eax' */ |
e430f34e AS |
813 | if (is_ereg(dst_reg) || is_ereg(src_reg)) |
814 | EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01); | |
62258278 AS |
815 | else |
816 | EMIT2(0xF0, 0x01); | |
817 | goto xadd; | |
818 | case BPF_STX | BPF_XADD | BPF_DW: | |
e430f34e | 819 | EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01); |
62258278 | 820 | xadd: if (is_imm8(insn->off)) |
e430f34e | 821 | EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); |
62258278 | 822 | else |
e430f34e | 823 | EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), |
62258278 AS |
824 | insn->off); |
825 | break; | |
826 | ||
827 | /* call */ | |
828 | case BPF_JMP | BPF_CALL: | |
e430f34e | 829 | func = (u8 *) __bpf_call_base + imm32; |
62258278 | 830 | jmp_offset = func - (image + addrs[i]); |
e430f34e | 831 | if (!imm32 || !is_simm32(jmp_offset)) { |
a2c7a983 | 832 | pr_err("unsupported BPF func %d addr %p image %p\n", |
e430f34e | 833 | imm32, func, image); |
62258278 AS |
834 | return -EINVAL; |
835 | } | |
836 | EMIT1_off32(0xE8, jmp_offset); | |
62258278 AS |
837 | break; |
838 | ||
71189fa9 | 839 | case BPF_JMP | BPF_TAIL_CALL: |
b52f00e6 AS |
840 | emit_bpf_tail_call(&prog); |
841 | break; | |
842 | ||
62258278 AS |
843 | /* cond jump */ |
844 | case BPF_JMP | BPF_JEQ | BPF_X: | |
845 | case BPF_JMP | BPF_JNE | BPF_X: | |
846 | case BPF_JMP | BPF_JGT | BPF_X: | |
52afc51e | 847 | case BPF_JMP | BPF_JLT | BPF_X: |
62258278 | 848 | case BPF_JMP | BPF_JGE | BPF_X: |
52afc51e | 849 | case BPF_JMP | BPF_JLE | BPF_X: |
62258278 | 850 | case BPF_JMP | BPF_JSGT | BPF_X: |
52afc51e | 851 | case BPF_JMP | BPF_JSLT | BPF_X: |
62258278 | 852 | case BPF_JMP | BPF_JSGE | BPF_X: |
52afc51e | 853 | case BPF_JMP | BPF_JSLE | BPF_X: |
3f5d6525 JW |
854 | case BPF_JMP32 | BPF_JEQ | BPF_X: |
855 | case BPF_JMP32 | BPF_JNE | BPF_X: | |
856 | case BPF_JMP32 | BPF_JGT | BPF_X: | |
857 | case BPF_JMP32 | BPF_JLT | BPF_X: | |
858 | case BPF_JMP32 | BPF_JGE | BPF_X: | |
859 | case BPF_JMP32 | BPF_JLE | BPF_X: | |
860 | case BPF_JMP32 | BPF_JSGT | BPF_X: | |
861 | case BPF_JMP32 | BPF_JSLT | BPF_X: | |
862 | case BPF_JMP32 | BPF_JSGE | BPF_X: | |
863 | case BPF_JMP32 | BPF_JSLE | BPF_X: | |
e430f34e | 864 | /* cmp dst_reg, src_reg */ |
3f5d6525 JW |
865 | if (BPF_CLASS(insn->code) == BPF_JMP) |
866 | EMIT1(add_2mod(0x48, dst_reg, src_reg)); | |
867 | else if (is_ereg(dst_reg) || is_ereg(src_reg)) | |
868 | EMIT1(add_2mod(0x40, dst_reg, src_reg)); | |
869 | EMIT2(0x39, add_2reg(0xC0, dst_reg, src_reg)); | |
62258278 AS |
870 | goto emit_cond_jmp; |
871 | ||
872 | case BPF_JMP | BPF_JSET | BPF_X: | |
3f5d6525 | 873 | case BPF_JMP32 | BPF_JSET | BPF_X: |
e430f34e | 874 | /* test dst_reg, src_reg */ |
3f5d6525 JW |
875 | if (BPF_CLASS(insn->code) == BPF_JMP) |
876 | EMIT1(add_2mod(0x48, dst_reg, src_reg)); | |
877 | else if (is_ereg(dst_reg) || is_ereg(src_reg)) | |
878 | EMIT1(add_2mod(0x40, dst_reg, src_reg)); | |
879 | EMIT2(0x85, add_2reg(0xC0, dst_reg, src_reg)); | |
62258278 AS |
880 | goto emit_cond_jmp; |
881 | ||
882 | case BPF_JMP | BPF_JSET | BPF_K: | |
3f5d6525 | 883 | case BPF_JMP32 | BPF_JSET | BPF_K: |
e430f34e | 884 | /* test dst_reg, imm32 */ |
3f5d6525 JW |
885 | if (BPF_CLASS(insn->code) == BPF_JMP) |
886 | EMIT1(add_1mod(0x48, dst_reg)); | |
887 | else if (is_ereg(dst_reg)) | |
888 | EMIT1(add_1mod(0x40, dst_reg)); | |
e430f34e | 889 | EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32); |
62258278 AS |
890 | goto emit_cond_jmp; |
891 | ||
892 | case BPF_JMP | BPF_JEQ | BPF_K: | |
893 | case BPF_JMP | BPF_JNE | BPF_K: | |
894 | case BPF_JMP | BPF_JGT | BPF_K: | |
52afc51e | 895 | case BPF_JMP | BPF_JLT | BPF_K: |
62258278 | 896 | case BPF_JMP | BPF_JGE | BPF_K: |
52afc51e | 897 | case BPF_JMP | BPF_JLE | BPF_K: |
62258278 | 898 | case BPF_JMP | BPF_JSGT | BPF_K: |
52afc51e | 899 | case BPF_JMP | BPF_JSLT | BPF_K: |
62258278 | 900 | case BPF_JMP | BPF_JSGE | BPF_K: |
52afc51e | 901 | case BPF_JMP | BPF_JSLE | BPF_K: |
3f5d6525 JW |
902 | case BPF_JMP32 | BPF_JEQ | BPF_K: |
903 | case BPF_JMP32 | BPF_JNE | BPF_K: | |
904 | case BPF_JMP32 | BPF_JGT | BPF_K: | |
905 | case BPF_JMP32 | BPF_JLT | BPF_K: | |
906 | case BPF_JMP32 | BPF_JGE | BPF_K: | |
907 | case BPF_JMP32 | BPF_JLE | BPF_K: | |
908 | case BPF_JMP32 | BPF_JSGT | BPF_K: | |
909 | case BPF_JMP32 | BPF_JSLT | BPF_K: | |
910 | case BPF_JMP32 | BPF_JSGE | BPF_K: | |
911 | case BPF_JMP32 | BPF_JSLE | BPF_K: | |
e430f34e | 912 | /* cmp dst_reg, imm8/32 */ |
3f5d6525 JW |
913 | if (BPF_CLASS(insn->code) == BPF_JMP) |
914 | EMIT1(add_1mod(0x48, dst_reg)); | |
915 | else if (is_ereg(dst_reg)) | |
916 | EMIT1(add_1mod(0x40, dst_reg)); | |
62258278 | 917 | |
e430f34e AS |
918 | if (is_imm8(imm32)) |
919 | EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32); | |
62258278 | 920 | else |
e430f34e | 921 | EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32); |
62258278 | 922 | |
a2c7a983 | 923 | emit_cond_jmp: /* Convert BPF opcode to x86 */ |
62258278 AS |
924 | switch (BPF_OP(insn->code)) { |
925 | case BPF_JEQ: | |
926 | jmp_cond = X86_JE; | |
927 | break; | |
928 | case BPF_JSET: | |
929 | case BPF_JNE: | |
930 | jmp_cond = X86_JNE; | |
931 | break; | |
932 | case BPF_JGT: | |
933 | /* GT is unsigned '>', JA in x86 */ | |
934 | jmp_cond = X86_JA; | |
935 | break; | |
52afc51e DB |
936 | case BPF_JLT: |
937 | /* LT is unsigned '<', JB in x86 */ | |
938 | jmp_cond = X86_JB; | |
939 | break; | |
62258278 AS |
940 | case BPF_JGE: |
941 | /* GE is unsigned '>=', JAE in x86 */ | |
942 | jmp_cond = X86_JAE; | |
943 | break; | |
52afc51e DB |
944 | case BPF_JLE: |
945 | /* LE is unsigned '<=', JBE in x86 */ | |
946 | jmp_cond = X86_JBE; | |
947 | break; | |
62258278 | 948 | case BPF_JSGT: |
a2c7a983 | 949 | /* Signed '>', GT in x86 */ |
62258278 AS |
950 | jmp_cond = X86_JG; |
951 | break; | |
52afc51e | 952 | case BPF_JSLT: |
a2c7a983 | 953 | /* Signed '<', LT in x86 */ |
52afc51e DB |
954 | jmp_cond = X86_JL; |
955 | break; | |
62258278 | 956 | case BPF_JSGE: |
a2c7a983 | 957 | /* Signed '>=', GE in x86 */ |
62258278 AS |
958 | jmp_cond = X86_JGE; |
959 | break; | |
52afc51e | 960 | case BPF_JSLE: |
a2c7a983 | 961 | /* Signed '<=', LE in x86 */ |
52afc51e DB |
962 | jmp_cond = X86_JLE; |
963 | break; | |
a2c7a983 | 964 | default: /* to silence GCC warning */ |
62258278 AS |
965 | return -EFAULT; |
966 | } | |
967 | jmp_offset = addrs[i + insn->off] - addrs[i]; | |
968 | if (is_imm8(jmp_offset)) { | |
969 | EMIT2(jmp_cond, jmp_offset); | |
970 | } else if (is_simm32(jmp_offset)) { | |
971 | EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset); | |
972 | } else { | |
973 | pr_err("cond_jmp gen bug %llx\n", jmp_offset); | |
974 | return -EFAULT; | |
975 | } | |
976 | ||
977 | break; | |
0a14842f | 978 | |
62258278 | 979 | case BPF_JMP | BPF_JA: |
1612a981 GB |
980 | if (insn->off == -1) |
981 | /* -1 jmp instructions will always jump | |
982 | * backwards two bytes. Explicitly handling | |
983 | * this case avoids wasting too many passes | |
984 | * when there are long sequences of replaced | |
985 | * dead code. | |
986 | */ | |
987 | jmp_offset = -2; | |
988 | else | |
989 | jmp_offset = addrs[i + insn->off] - addrs[i]; | |
990 | ||
62258278 | 991 | if (!jmp_offset) |
a2c7a983 | 992 | /* Optimize out nop jumps */ |
62258278 AS |
993 | break; |
994 | emit_jmp: | |
995 | if (is_imm8(jmp_offset)) { | |
996 | EMIT2(0xEB, jmp_offset); | |
997 | } else if (is_simm32(jmp_offset)) { | |
998 | EMIT1_off32(0xE9, jmp_offset); | |
999 | } else { | |
1000 | pr_err("jmp gen bug %llx\n", jmp_offset); | |
1001 | return -EFAULT; | |
1002 | } | |
1003 | break; | |
1004 | ||
62258278 | 1005 | case BPF_JMP | BPF_EXIT: |
769e0de6 | 1006 | if (seen_exit) { |
62258278 AS |
1007 | jmp_offset = ctx->cleanup_addr - addrs[i]; |
1008 | goto emit_jmp; | |
1009 | } | |
769e0de6 | 1010 | seen_exit = true; |
a2c7a983 | 1011 | /* Update cleanup_addr */ |
62258278 | 1012 | ctx->cleanup_addr = proglen; |
fe8d9571 AS |
1013 | if (!bpf_prog_was_classic(bpf_prog)) |
1014 | EMIT1(0x5B); /* get rid of tail_call_cnt */ | |
1015 | EMIT2(0x41, 0x5F); /* pop r15 */ | |
1016 | EMIT2(0x41, 0x5E); /* pop r14 */ | |
1017 | EMIT2(0x41, 0x5D); /* pop r13 */ | |
1018 | EMIT1(0x5B); /* pop rbx */ | |
1019 | EMIT1(0xC9); /* leave */ | |
1020 | EMIT1(0xC3); /* ret */ | |
62258278 AS |
1021 | break; |
1022 | ||
f3c2af7b | 1023 | default: |
a2c7a983 IM |
1024 | /* |
1025 | * By design x86-64 JIT should support all BPF instructions. | |
62258278 | 1026 | * This error will be seen if new instruction was added |
a2c7a983 IM |
1027 | * to the interpreter, but not to the JIT, or if there is |
1028 | * junk in bpf_prog. | |
62258278 AS |
1029 | */ |
1030 | pr_err("bpf_jit: unknown opcode %02x\n", insn->code); | |
f3c2af7b AS |
1031 | return -EINVAL; |
1032 | } | |
62258278 | 1033 | |
f3c2af7b | 1034 | ilen = prog - temp; |
e0ee9c12 | 1035 | if (ilen > BPF_MAX_INSN_SIZE) { |
9383191d | 1036 | pr_err("bpf_jit: fatal insn size error\n"); |
e0ee9c12 AS |
1037 | return -EFAULT; |
1038 | } | |
1039 | ||
f3c2af7b AS |
1040 | if (image) { |
1041 | if (unlikely(proglen + ilen > oldproglen)) { | |
9383191d | 1042 | pr_err("bpf_jit: fatal error\n"); |
f3c2af7b | 1043 | return -EFAULT; |
0a14842f | 1044 | } |
f3c2af7b | 1045 | memcpy(image + proglen, temp, ilen); |
0a14842f | 1046 | } |
f3c2af7b AS |
1047 | proglen += ilen; |
1048 | addrs[i] = proglen; | |
1049 | prog = temp; | |
1050 | } | |
f3c2af7b AS |
1051 | return proglen; |
1052 | } | |
1053 | ||
1c2a088a AS |
1054 | struct x64_jit_data { |
1055 | struct bpf_binary_header *header; | |
1056 | int *addrs; | |
1057 | u8 *image; | |
1058 | int proglen; | |
1059 | struct jit_context ctx; | |
1060 | }; | |
1061 | ||
d1c55ab5 | 1062 | struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) |
f3c2af7b AS |
1063 | { |
1064 | struct bpf_binary_header *header = NULL; | |
959a7579 | 1065 | struct bpf_prog *tmp, *orig_prog = prog; |
1c2a088a | 1066 | struct x64_jit_data *jit_data; |
f3c2af7b AS |
1067 | int proglen, oldproglen = 0; |
1068 | struct jit_context ctx = {}; | |
959a7579 | 1069 | bool tmp_blinded = false; |
1c2a088a | 1070 | bool extra_pass = false; |
f3c2af7b AS |
1071 | u8 *image = NULL; |
1072 | int *addrs; | |
1073 | int pass; | |
1074 | int i; | |
1075 | ||
60b58afc | 1076 | if (!prog->jit_requested) |
959a7579 DB |
1077 | return orig_prog; |
1078 | ||
1079 | tmp = bpf_jit_blind_constants(prog); | |
a2c7a983 IM |
1080 | /* |
1081 | * If blinding was requested and we failed during blinding, | |
959a7579 DB |
1082 | * we must fall back to the interpreter. |
1083 | */ | |
1084 | if (IS_ERR(tmp)) | |
1085 | return orig_prog; | |
1086 | if (tmp != prog) { | |
1087 | tmp_blinded = true; | |
1088 | prog = tmp; | |
1089 | } | |
0a14842f | 1090 | |
1c2a088a AS |
1091 | jit_data = prog->aux->jit_data; |
1092 | if (!jit_data) { | |
1093 | jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); | |
1094 | if (!jit_data) { | |
1095 | prog = orig_prog; | |
1096 | goto out; | |
1097 | } | |
1098 | prog->aux->jit_data = jit_data; | |
1099 | } | |
1100 | addrs = jit_data->addrs; | |
1101 | if (addrs) { | |
1102 | ctx = jit_data->ctx; | |
1103 | oldproglen = jit_data->proglen; | |
1104 | image = jit_data->image; | |
1105 | header = jit_data->header; | |
1106 | extra_pass = true; | |
1107 | goto skip_init_addrs; | |
1108 | } | |
7c2e988f | 1109 | addrs = kmalloc_array(prog->len + 1, sizeof(*addrs), GFP_KERNEL); |
959a7579 DB |
1110 | if (!addrs) { |
1111 | prog = orig_prog; | |
1c2a088a | 1112 | goto out_addrs; |
959a7579 | 1113 | } |
f3c2af7b | 1114 | |
a2c7a983 IM |
1115 | /* |
1116 | * Before first pass, make a rough estimation of addrs[] | |
1117 | * each BPF instruction is translated to less than 64 bytes | |
f3c2af7b | 1118 | */ |
7c2e988f | 1119 | for (proglen = 0, i = 0; i <= prog->len; i++) { |
f3c2af7b AS |
1120 | proglen += 64; |
1121 | addrs[i] = proglen; | |
1122 | } | |
1123 | ctx.cleanup_addr = proglen; | |
1c2a088a | 1124 | skip_init_addrs: |
f3c2af7b | 1125 | |
a2c7a983 IM |
1126 | /* |
1127 | * JITed image shrinks with every pass and the loop iterates | |
1128 | * until the image stops shrinking. Very large BPF programs | |
3f7352bf | 1129 | * may converge on the last pass. In such case do one more |
a2c7a983 | 1130 | * pass to emit the final image. |
3f7352bf | 1131 | */ |
6007b080 | 1132 | for (pass = 0; pass < 20 || image; pass++) { |
f3c2af7b AS |
1133 | proglen = do_jit(prog, addrs, image, oldproglen, &ctx); |
1134 | if (proglen <= 0) { | |
3aab8884 | 1135 | out_image: |
f3c2af7b AS |
1136 | image = NULL; |
1137 | if (header) | |
738cbe72 | 1138 | bpf_jit_binary_free(header); |
959a7579 DB |
1139 | prog = orig_prog; |
1140 | goto out_addrs; | |
f3c2af7b | 1141 | } |
0a14842f | 1142 | if (image) { |
e0ee9c12 | 1143 | if (proglen != oldproglen) { |
f3c2af7b AS |
1144 | pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", |
1145 | proglen, oldproglen); | |
3aab8884 | 1146 | goto out_image; |
e0ee9c12 | 1147 | } |
0a14842f ED |
1148 | break; |
1149 | } | |
1150 | if (proglen == oldproglen) { | |
738cbe72 DB |
1151 | header = bpf_jit_binary_alloc(proglen, &image, |
1152 | 1, jit_fill_hole); | |
959a7579 DB |
1153 | if (!header) { |
1154 | prog = orig_prog; | |
1155 | goto out_addrs; | |
1156 | } | |
0a14842f ED |
1157 | } |
1158 | oldproglen = proglen; | |
6007b080 | 1159 | cond_resched(); |
0a14842f | 1160 | } |
79617801 | 1161 | |
0a14842f | 1162 | if (bpf_jit_enable > 1) |
485d6511 | 1163 | bpf_jit_dump(prog->len, proglen, pass + 1, image); |
0a14842f ED |
1164 | |
1165 | if (image) { | |
1c2a088a AS |
1166 | if (!prog->is_func || extra_pass) { |
1167 | bpf_jit_binary_lock_ro(header); | |
1168 | } else { | |
1169 | jit_data->addrs = addrs; | |
1170 | jit_data->ctx = ctx; | |
1171 | jit_data->proglen = proglen; | |
1172 | jit_data->image = image; | |
1173 | jit_data->header = header; | |
1174 | } | |
f3c2af7b | 1175 | prog->bpf_func = (void *)image; |
a91263d5 | 1176 | prog->jited = 1; |
783d28dd | 1177 | prog->jited_len = proglen; |
9d5ecb09 DB |
1178 | } else { |
1179 | prog = orig_prog; | |
0a14842f | 1180 | } |
959a7579 | 1181 | |
39f56ca9 | 1182 | if (!image || !prog->is_func || extra_pass) { |
c454a46b | 1183 | if (image) |
7c2e988f | 1184 | bpf_prog_fill_jited_linfo(prog, addrs + 1); |
959a7579 | 1185 | out_addrs: |
1c2a088a AS |
1186 | kfree(addrs); |
1187 | kfree(jit_data); | |
1188 | prog->aux->jit_data = NULL; | |
1189 | } | |
959a7579 DB |
1190 | out: |
1191 | if (tmp_blinded) | |
1192 | bpf_jit_prog_release_other(prog, prog == orig_prog ? | |
1193 | tmp : orig_prog); | |
d1c55ab5 | 1194 | return prog; |
0a14842f | 1195 | } |