10a14842fSEric Dumazet /* bpf_jit_comp.c : BPF JIT compiler 20a14842fSEric Dumazet * 33b58908aSEric Dumazet * Copyright (C) 2011-2013 Eric Dumazet (eric.dumazet@gmail.com) 462258278SAlexei Starovoitov * Internal BPF Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 50a14842fSEric Dumazet * 60a14842fSEric Dumazet * This program is free software; you can redistribute it and/or 70a14842fSEric Dumazet * modify it under the terms of the GNU General Public License 80a14842fSEric Dumazet * as published by the Free Software Foundation; version 2 90a14842fSEric Dumazet * of the License. 100a14842fSEric Dumazet */ 110a14842fSEric Dumazet #include <linux/netdevice.h> 120a14842fSEric Dumazet #include <linux/filter.h> 13855ddb56SEric Dumazet #include <linux/if_vlan.h> 14738cbe72SDaniel Borkmann #include <asm/cacheflush.h> 15b52f00e6SAlexei Starovoitov #include <linux/bpf.h> 160a14842fSEric Dumazet 170a14842fSEric Dumazet int bpf_jit_enable __read_mostly; 180a14842fSEric Dumazet 190a14842fSEric Dumazet /* 200a14842fSEric Dumazet * assembly code in arch/x86/net/bpf_jit.S 210a14842fSEric Dumazet */ 2262258278SAlexei Starovoitov extern u8 sk_load_word[], sk_load_half[], sk_load_byte[]; 23a998d434SJan Seiffert extern u8 sk_load_word_positive_offset[], sk_load_half_positive_offset[]; 2462258278SAlexei Starovoitov extern u8 sk_load_byte_positive_offset[]; 25a998d434SJan Seiffert extern u8 sk_load_word_negative_offset[], sk_load_half_negative_offset[]; 2662258278SAlexei Starovoitov extern u8 sk_load_byte_negative_offset[]; 270a14842fSEric Dumazet 285cccc702SJoe Perches static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) 290a14842fSEric Dumazet { 300a14842fSEric Dumazet if (len == 1) 310a14842fSEric Dumazet *ptr = bytes; 320a14842fSEric Dumazet else if (len == 2) 330a14842fSEric Dumazet *(u16 *)ptr = bytes; 340a14842fSEric Dumazet else { 350a14842fSEric Dumazet *(u32 *)ptr = bytes; 360a14842fSEric Dumazet barrier(); 370a14842fSEric Dumazet } 380a14842fSEric Dumazet return ptr + len; 390a14842fSEric Dumazet } 400a14842fSEric Dumazet 41b52f00e6SAlexei Starovoitov #define EMIT(bytes, len) \ 42b52f00e6SAlexei Starovoitov do { prog = emit_code(prog, bytes, len); cnt += len; } while (0) 430a14842fSEric Dumazet 440a14842fSEric Dumazet #define EMIT1(b1) EMIT(b1, 1) 450a14842fSEric Dumazet #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2) 460a14842fSEric Dumazet #define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3) 470a14842fSEric Dumazet #define EMIT4(b1, b2, b3, b4) EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4) 4862258278SAlexei Starovoitov #define EMIT1_off32(b1, off) \ 4962258278SAlexei Starovoitov do {EMIT1(b1); EMIT(off, 4); } while (0) 5062258278SAlexei Starovoitov #define EMIT2_off32(b1, b2, off) \ 5162258278SAlexei Starovoitov do {EMIT2(b1, b2); EMIT(off, 4); } while (0) 5262258278SAlexei Starovoitov #define EMIT3_off32(b1, b2, b3, off) \ 5362258278SAlexei Starovoitov do {EMIT3(b1, b2, b3); EMIT(off, 4); } while (0) 5462258278SAlexei Starovoitov #define EMIT4_off32(b1, b2, b3, b4, off) \ 5562258278SAlexei Starovoitov do {EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0) 560a14842fSEric Dumazet 575cccc702SJoe Perches static bool is_imm8(int value) 580a14842fSEric Dumazet { 590a14842fSEric Dumazet return value <= 127 && value >= -128; 600a14842fSEric Dumazet } 610a14842fSEric Dumazet 625cccc702SJoe Perches static bool is_simm32(s64 value) 630a14842fSEric Dumazet { 6462258278SAlexei Starovoitov return value == (s64) (s32) value; 650a14842fSEric Dumazet } 660a14842fSEric Dumazet 67e430f34eSAlexei Starovoitov /* mov dst, src */ 68e430f34eSAlexei Starovoitov #define EMIT_mov(DST, SRC) \ 69e430f34eSAlexei Starovoitov do {if (DST != SRC) \ 70e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \ 710a14842fSEric Dumazet } while (0) 720a14842fSEric Dumazet 7362258278SAlexei Starovoitov static int bpf_size_to_x86_bytes(int bpf_size) 7462258278SAlexei Starovoitov { 7562258278SAlexei Starovoitov if (bpf_size == BPF_W) 7662258278SAlexei Starovoitov return 4; 7762258278SAlexei Starovoitov else if (bpf_size == BPF_H) 7862258278SAlexei Starovoitov return 2; 7962258278SAlexei Starovoitov else if (bpf_size == BPF_B) 8062258278SAlexei Starovoitov return 1; 8162258278SAlexei Starovoitov else if (bpf_size == BPF_DW) 8262258278SAlexei Starovoitov return 4; /* imm32 */ 8362258278SAlexei Starovoitov else 8462258278SAlexei Starovoitov return 0; 8562258278SAlexei Starovoitov } 8662258278SAlexei Starovoitov 870a14842fSEric Dumazet /* list of x86 cond jumps opcodes (. + s8) 880a14842fSEric Dumazet * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32) 890a14842fSEric Dumazet */ 900a14842fSEric Dumazet #define X86_JB 0x72 910a14842fSEric Dumazet #define X86_JAE 0x73 920a14842fSEric Dumazet #define X86_JE 0x74 930a14842fSEric Dumazet #define X86_JNE 0x75 940a14842fSEric Dumazet #define X86_JBE 0x76 950a14842fSEric Dumazet #define X86_JA 0x77 9662258278SAlexei Starovoitov #define X86_JGE 0x7D 9762258278SAlexei Starovoitov #define X86_JG 0x7F 980a14842fSEric Dumazet 995cccc702SJoe Perches static void bpf_flush_icache(void *start, void *end) 1000a14842fSEric Dumazet { 1010a14842fSEric Dumazet mm_segment_t old_fs = get_fs(); 1020a14842fSEric Dumazet 1030a14842fSEric Dumazet set_fs(KERNEL_DS); 1040a14842fSEric Dumazet smp_wmb(); 1050a14842fSEric Dumazet flush_icache_range((unsigned long)start, (unsigned long)end); 1060a14842fSEric Dumazet set_fs(old_fs); 1070a14842fSEric Dumazet } 1080a14842fSEric Dumazet 109a998d434SJan Seiffert #define CHOOSE_LOAD_FUNC(K, func) \ 110a998d434SJan Seiffert ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) 1110a14842fSEric Dumazet 11262258278SAlexei Starovoitov /* pick a register outside of BPF range for JIT internal work */ 11362258278SAlexei Starovoitov #define AUX_REG (MAX_BPF_REG + 1) 11462258278SAlexei Starovoitov 11562258278SAlexei Starovoitov /* the following table maps BPF registers to x64 registers. 11662258278SAlexei Starovoitov * x64 register r12 is unused, since if used as base address register 11762258278SAlexei Starovoitov * in load/store instructions, it always needs an extra byte of encoding 11862258278SAlexei Starovoitov */ 11962258278SAlexei Starovoitov static const int reg2hex[] = { 12062258278SAlexei Starovoitov [BPF_REG_0] = 0, /* rax */ 12162258278SAlexei Starovoitov [BPF_REG_1] = 7, /* rdi */ 12262258278SAlexei Starovoitov [BPF_REG_2] = 6, /* rsi */ 12362258278SAlexei Starovoitov [BPF_REG_3] = 2, /* rdx */ 12462258278SAlexei Starovoitov [BPF_REG_4] = 1, /* rcx */ 12562258278SAlexei Starovoitov [BPF_REG_5] = 0, /* r8 */ 12662258278SAlexei Starovoitov [BPF_REG_6] = 3, /* rbx callee saved */ 12762258278SAlexei Starovoitov [BPF_REG_7] = 5, /* r13 callee saved */ 12862258278SAlexei Starovoitov [BPF_REG_8] = 6, /* r14 callee saved */ 12962258278SAlexei Starovoitov [BPF_REG_9] = 7, /* r15 callee saved */ 13062258278SAlexei Starovoitov [BPF_REG_FP] = 5, /* rbp readonly */ 13162258278SAlexei Starovoitov [AUX_REG] = 3, /* r11 temp register */ 13262258278SAlexei Starovoitov }; 13362258278SAlexei Starovoitov 13462258278SAlexei Starovoitov /* is_ereg() == true if BPF register 'reg' maps to x64 r8..r15 13562258278SAlexei Starovoitov * which need extra byte of encoding. 13662258278SAlexei Starovoitov * rax,rcx,...,rbp have simpler encoding 13762258278SAlexei Starovoitov */ 1385cccc702SJoe Perches static bool is_ereg(u32 reg) 13962258278SAlexei Starovoitov { 140d148134bSJoe Perches return (1 << reg) & (BIT(BPF_REG_5) | 141d148134bSJoe Perches BIT(AUX_REG) | 142d148134bSJoe Perches BIT(BPF_REG_7) | 143d148134bSJoe Perches BIT(BPF_REG_8) | 144d148134bSJoe Perches BIT(BPF_REG_9)); 14562258278SAlexei Starovoitov } 14662258278SAlexei Starovoitov 14762258278SAlexei Starovoitov /* add modifiers if 'reg' maps to x64 registers r8..r15 */ 1485cccc702SJoe Perches static u8 add_1mod(u8 byte, u32 reg) 14962258278SAlexei Starovoitov { 15062258278SAlexei Starovoitov if (is_ereg(reg)) 15162258278SAlexei Starovoitov byte |= 1; 15262258278SAlexei Starovoitov return byte; 15362258278SAlexei Starovoitov } 15462258278SAlexei Starovoitov 1555cccc702SJoe Perches static u8 add_2mod(u8 byte, u32 r1, u32 r2) 15662258278SAlexei Starovoitov { 15762258278SAlexei Starovoitov if (is_ereg(r1)) 15862258278SAlexei Starovoitov byte |= 1; 15962258278SAlexei Starovoitov if (is_ereg(r2)) 16062258278SAlexei Starovoitov byte |= 4; 16162258278SAlexei Starovoitov return byte; 16262258278SAlexei Starovoitov } 16362258278SAlexei Starovoitov 164e430f34eSAlexei Starovoitov /* encode 'dst_reg' register into x64 opcode 'byte' */ 1655cccc702SJoe Perches static u8 add_1reg(u8 byte, u32 dst_reg) 16662258278SAlexei Starovoitov { 167e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg]; 16862258278SAlexei Starovoitov } 16962258278SAlexei Starovoitov 170e430f34eSAlexei Starovoitov /* encode 'dst_reg' and 'src_reg' registers into x64 opcode 'byte' */ 1715cccc702SJoe Perches static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg) 17262258278SAlexei Starovoitov { 173e430f34eSAlexei Starovoitov return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3); 17462258278SAlexei Starovoitov } 17562258278SAlexei Starovoitov 176738cbe72SDaniel Borkmann static void jit_fill_hole(void *area, unsigned int size) 177738cbe72SDaniel Borkmann { 178738cbe72SDaniel Borkmann /* fill whole space with int3 instructions */ 179738cbe72SDaniel Borkmann memset(area, 0xcc, size); 180738cbe72SDaniel Borkmann } 181738cbe72SDaniel Borkmann 182f3c2af7bSAlexei Starovoitov struct jit_context { 183769e0de6SAlexei Starovoitov int cleanup_addr; /* epilogue code offset */ 18462258278SAlexei Starovoitov bool seen_ld_abs; 185f3c2af7bSAlexei Starovoitov }; 186f3c2af7bSAlexei Starovoitov 187e0ee9c12SAlexei Starovoitov /* maximum number of bytes emitted while JITing one eBPF insn */ 188e0ee9c12SAlexei Starovoitov #define BPF_MAX_INSN_SIZE 128 189e0ee9c12SAlexei Starovoitov #define BPF_INSN_SAFETY 64 190e0ee9c12SAlexei Starovoitov 191b52f00e6SAlexei Starovoitov #define STACKSIZE \ 192b52f00e6SAlexei Starovoitov (MAX_BPF_STACK + \ 193b52f00e6SAlexei Starovoitov 32 /* space for rbx, r13, r14, r15 */ + \ 194b52f00e6SAlexei Starovoitov 8 /* space for skb_copy_bits() buffer */) 195b52f00e6SAlexei Starovoitov 196b52f00e6SAlexei Starovoitov #define PROLOGUE_SIZE 51 197b52f00e6SAlexei Starovoitov 198b52f00e6SAlexei Starovoitov /* emit x64 prologue code for BPF program and check it's size. 199b52f00e6SAlexei Starovoitov * bpf_tail_call helper will skip it while jumping into another program 200b52f00e6SAlexei Starovoitov */ 201b52f00e6SAlexei Starovoitov static void emit_prologue(u8 **pprog) 2020a14842fSEric Dumazet { 203b52f00e6SAlexei Starovoitov u8 *prog = *pprog; 204b52f00e6SAlexei Starovoitov int cnt = 0; 2050a14842fSEric Dumazet 20662258278SAlexei Starovoitov EMIT1(0x55); /* push rbp */ 20762258278SAlexei Starovoitov EMIT3(0x48, 0x89, 0xE5); /* mov rbp,rsp */ 2080a14842fSEric Dumazet 209b52f00e6SAlexei Starovoitov /* sub rsp, STACKSIZE */ 210b52f00e6SAlexei Starovoitov EMIT3_off32(0x48, 0x81, 0xEC, STACKSIZE); 2110a14842fSEric Dumazet 21262258278SAlexei Starovoitov /* all classic BPF filters use R6(rbx) save it */ 21362258278SAlexei Starovoitov 21462258278SAlexei Starovoitov /* mov qword ptr [rbp-X],rbx */ 215b52f00e6SAlexei Starovoitov EMIT3_off32(0x48, 0x89, 0x9D, -STACKSIZE); 21662258278SAlexei Starovoitov 2178fb575caSAlexei Starovoitov /* bpf_convert_filter() maps classic BPF register X to R7 and uses R8 21862258278SAlexei Starovoitov * as temporary, so all tcpdump filters need to spill/fill R7(r13) and 21962258278SAlexei Starovoitov * R8(r14). R9(r15) spill could be made conditional, but there is only 22062258278SAlexei Starovoitov * one 'bpf_error' return path out of helper functions inside bpf_jit.S 22162258278SAlexei Starovoitov * The overhead of extra spill is negligible for any filter other 22262258278SAlexei Starovoitov * than synthetic ones. Therefore not worth adding complexity. 2230a14842fSEric Dumazet */ 22462258278SAlexei Starovoitov 22562258278SAlexei Starovoitov /* mov qword ptr [rbp-X],r13 */ 226b52f00e6SAlexei Starovoitov EMIT3_off32(0x4C, 0x89, 0xAD, -STACKSIZE + 8); 22762258278SAlexei Starovoitov /* mov qword ptr [rbp-X],r14 */ 228b52f00e6SAlexei Starovoitov EMIT3_off32(0x4C, 0x89, 0xB5, -STACKSIZE + 16); 22962258278SAlexei Starovoitov /* mov qword ptr [rbp-X],r15 */ 230b52f00e6SAlexei Starovoitov EMIT3_off32(0x4C, 0x89, 0xBD, -STACKSIZE + 24); 23162258278SAlexei Starovoitov 23262258278SAlexei Starovoitov /* clear A and X registers */ 23362258278SAlexei Starovoitov EMIT2(0x31, 0xc0); /* xor eax, eax */ 23462258278SAlexei Starovoitov EMIT3(0x4D, 0x31, 0xED); /* xor r13, r13 */ 23562258278SAlexei Starovoitov 236b52f00e6SAlexei Starovoitov /* clear tail_cnt: mov qword ptr [rbp-X], rax */ 237b52f00e6SAlexei Starovoitov EMIT3_off32(0x48, 0x89, 0x85, -STACKSIZE + 32); 238b52f00e6SAlexei Starovoitov 239b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt != PROLOGUE_SIZE); 240b52f00e6SAlexei Starovoitov *pprog = prog; 241b52f00e6SAlexei Starovoitov } 242b52f00e6SAlexei Starovoitov 243b52f00e6SAlexei Starovoitov /* generate the following code: 244b52f00e6SAlexei Starovoitov * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ... 245b52f00e6SAlexei Starovoitov * if (index >= array->map.max_entries) 246b52f00e6SAlexei Starovoitov * goto out; 247b52f00e6SAlexei Starovoitov * if (++tail_call_cnt > MAX_TAIL_CALL_CNT) 248b52f00e6SAlexei Starovoitov * goto out; 249b52f00e6SAlexei Starovoitov * prog = array->prog[index]; 250b52f00e6SAlexei Starovoitov * if (prog == NULL) 251b52f00e6SAlexei Starovoitov * goto out; 252b52f00e6SAlexei Starovoitov * goto *(prog->bpf_func + prologue_size); 253b52f00e6SAlexei Starovoitov * out: 254b52f00e6SAlexei Starovoitov */ 255b52f00e6SAlexei Starovoitov static void emit_bpf_tail_call(u8 **pprog) 256b52f00e6SAlexei Starovoitov { 257b52f00e6SAlexei Starovoitov u8 *prog = *pprog; 258b52f00e6SAlexei Starovoitov int label1, label2, label3; 259b52f00e6SAlexei Starovoitov int cnt = 0; 260b52f00e6SAlexei Starovoitov 261b52f00e6SAlexei Starovoitov /* rdi - pointer to ctx 262b52f00e6SAlexei Starovoitov * rsi - pointer to bpf_array 263b52f00e6SAlexei Starovoitov * rdx - index in bpf_array 264b52f00e6SAlexei Starovoitov */ 265b52f00e6SAlexei Starovoitov 266b52f00e6SAlexei Starovoitov /* if (index >= array->map.max_entries) 267b52f00e6SAlexei Starovoitov * goto out; 268b52f00e6SAlexei Starovoitov */ 269b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x8B, 0x46, /* mov rax, qword ptr [rsi + 16] */ 270b52f00e6SAlexei Starovoitov offsetof(struct bpf_array, map.max_entries)); 271b52f00e6SAlexei Starovoitov EMIT3(0x48, 0x39, 0xD0); /* cmp rax, rdx */ 272b52f00e6SAlexei Starovoitov #define OFFSET1 44 /* number of bytes to jump */ 273b52f00e6SAlexei Starovoitov EMIT2(X86_JBE, OFFSET1); /* jbe out */ 274b52f00e6SAlexei Starovoitov label1 = cnt; 275b52f00e6SAlexei Starovoitov 276b52f00e6SAlexei Starovoitov /* if (tail_call_cnt > MAX_TAIL_CALL_CNT) 277b52f00e6SAlexei Starovoitov * goto out; 278b52f00e6SAlexei Starovoitov */ 279b52f00e6SAlexei Starovoitov EMIT2_off32(0x8B, 0x85, -STACKSIZE + 36); /* mov eax, dword ptr [rbp - 516] */ 280b52f00e6SAlexei Starovoitov EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT); /* cmp eax, MAX_TAIL_CALL_CNT */ 281b52f00e6SAlexei Starovoitov #define OFFSET2 33 282b52f00e6SAlexei Starovoitov EMIT2(X86_JA, OFFSET2); /* ja out */ 283b52f00e6SAlexei Starovoitov label2 = cnt; 284b52f00e6SAlexei Starovoitov EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */ 285b52f00e6SAlexei Starovoitov EMIT2_off32(0x89, 0x85, -STACKSIZE + 36); /* mov dword ptr [rbp - 516], eax */ 286b52f00e6SAlexei Starovoitov 287b52f00e6SAlexei Starovoitov /* prog = array->prog[index]; */ 288b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x8D, 0x44, 0xD6); /* lea rax, [rsi + rdx * 8 + 0x50] */ 289b52f00e6SAlexei Starovoitov EMIT1(offsetof(struct bpf_array, prog)); 290b52f00e6SAlexei Starovoitov EMIT3(0x48, 0x8B, 0x00); /* mov rax, qword ptr [rax] */ 291b52f00e6SAlexei Starovoitov 292b52f00e6SAlexei Starovoitov /* if (prog == NULL) 293b52f00e6SAlexei Starovoitov * goto out; 294b52f00e6SAlexei Starovoitov */ 295b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x83, 0xF8, 0x00); /* cmp rax, 0 */ 296b52f00e6SAlexei Starovoitov #define OFFSET3 10 297b52f00e6SAlexei Starovoitov EMIT2(X86_JE, OFFSET3); /* je out */ 298b52f00e6SAlexei Starovoitov label3 = cnt; 299b52f00e6SAlexei Starovoitov 300b52f00e6SAlexei Starovoitov /* goto *(prog->bpf_func + prologue_size); */ 301b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x8B, 0x40, /* mov rax, qword ptr [rax + 32] */ 302b52f00e6SAlexei Starovoitov offsetof(struct bpf_prog, bpf_func)); 303b52f00e6SAlexei Starovoitov EMIT4(0x48, 0x83, 0xC0, PROLOGUE_SIZE); /* add rax, prologue_size */ 304b52f00e6SAlexei Starovoitov 305b52f00e6SAlexei Starovoitov /* now we're ready to jump into next BPF program 306b52f00e6SAlexei Starovoitov * rdi == ctx (1st arg) 307b52f00e6SAlexei Starovoitov * rax == prog->bpf_func + prologue_size 308b52f00e6SAlexei Starovoitov */ 309b52f00e6SAlexei Starovoitov EMIT2(0xFF, 0xE0); /* jmp rax */ 310b52f00e6SAlexei Starovoitov 311b52f00e6SAlexei Starovoitov /* out: */ 312b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label1 != OFFSET1); 313b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label2 != OFFSET2); 314b52f00e6SAlexei Starovoitov BUILD_BUG_ON(cnt - label3 != OFFSET3); 315b52f00e6SAlexei Starovoitov *pprog = prog; 316b52f00e6SAlexei Starovoitov } 317b52f00e6SAlexei Starovoitov 3184e10df9aSAlexei Starovoitov 3194e10df9aSAlexei Starovoitov static void emit_load_skb_data_hlen(u8 **pprog) 3204e10df9aSAlexei Starovoitov { 3214e10df9aSAlexei Starovoitov u8 *prog = *pprog; 3224e10df9aSAlexei Starovoitov int cnt = 0; 3234e10df9aSAlexei Starovoitov 3244e10df9aSAlexei Starovoitov /* r9d = skb->len - skb->data_len (headlen) 3254e10df9aSAlexei Starovoitov * r10 = skb->data 3264e10df9aSAlexei Starovoitov */ 3274e10df9aSAlexei Starovoitov /* mov %r9d, off32(%rdi) */ 3284e10df9aSAlexei Starovoitov EMIT3_off32(0x44, 0x8b, 0x8f, offsetof(struct sk_buff, len)); 3294e10df9aSAlexei Starovoitov 3304e10df9aSAlexei Starovoitov /* sub %r9d, off32(%rdi) */ 3314e10df9aSAlexei Starovoitov EMIT3_off32(0x44, 0x2b, 0x8f, offsetof(struct sk_buff, data_len)); 3324e10df9aSAlexei Starovoitov 3334e10df9aSAlexei Starovoitov /* mov %r10, off32(%rdi) */ 3344e10df9aSAlexei Starovoitov EMIT3_off32(0x4c, 0x8b, 0x97, offsetof(struct sk_buff, data)); 3354e10df9aSAlexei Starovoitov *pprog = prog; 3364e10df9aSAlexei Starovoitov } 3374e10df9aSAlexei Starovoitov 338b52f00e6SAlexei Starovoitov static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, 339b52f00e6SAlexei Starovoitov int oldproglen, struct jit_context *ctx) 340b52f00e6SAlexei Starovoitov { 341b52f00e6SAlexei Starovoitov struct bpf_insn *insn = bpf_prog->insnsi; 342b52f00e6SAlexei Starovoitov int insn_cnt = bpf_prog->len; 343b52f00e6SAlexei Starovoitov bool seen_ld_abs = ctx->seen_ld_abs | (oldproglen == 0); 344b52f00e6SAlexei Starovoitov bool seen_exit = false; 345b52f00e6SAlexei Starovoitov u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY]; 346b52f00e6SAlexei Starovoitov int i, cnt = 0; 347b52f00e6SAlexei Starovoitov int proglen = 0; 348b52f00e6SAlexei Starovoitov u8 *prog = temp; 349b52f00e6SAlexei Starovoitov 350b52f00e6SAlexei Starovoitov emit_prologue(&prog); 351b52f00e6SAlexei Starovoitov 3524e10df9aSAlexei Starovoitov if (seen_ld_abs) 3534e10df9aSAlexei Starovoitov emit_load_skb_data_hlen(&prog); 35462258278SAlexei Starovoitov 35562258278SAlexei Starovoitov for (i = 0; i < insn_cnt; i++, insn++) { 356e430f34eSAlexei Starovoitov const s32 imm32 = insn->imm; 357e430f34eSAlexei Starovoitov u32 dst_reg = insn->dst_reg; 358e430f34eSAlexei Starovoitov u32 src_reg = insn->src_reg; 35962258278SAlexei Starovoitov u8 b1 = 0, b2 = 0, b3 = 0; 36062258278SAlexei Starovoitov s64 jmp_offset; 36162258278SAlexei Starovoitov u8 jmp_cond; 3624e10df9aSAlexei Starovoitov bool reload_skb_data; 36362258278SAlexei Starovoitov int ilen; 36462258278SAlexei Starovoitov u8 *func; 36562258278SAlexei Starovoitov 36662258278SAlexei Starovoitov switch (insn->code) { 36762258278SAlexei Starovoitov /* ALU */ 36862258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_X: 36962258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_X: 37062258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_X: 37162258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_X: 37262258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_X: 37362258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_X: 37462258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_X: 37562258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_X: 37662258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_X: 37762258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_X: 37862258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 37962258278SAlexei Starovoitov case BPF_ADD: b2 = 0x01; break; 38062258278SAlexei Starovoitov case BPF_SUB: b2 = 0x29; break; 38162258278SAlexei Starovoitov case BPF_AND: b2 = 0x21; break; 38262258278SAlexei Starovoitov case BPF_OR: b2 = 0x09; break; 38362258278SAlexei Starovoitov case BPF_XOR: b2 = 0x31; break; 38462258278SAlexei Starovoitov } 38562258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 386e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x48, dst_reg, src_reg)); 387e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg) || is_ereg(src_reg)) 388e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 389e430f34eSAlexei Starovoitov EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg)); 3900a14842fSEric Dumazet break; 39162258278SAlexei Starovoitov 392e430f34eSAlexei Starovoitov /* mov dst, src */ 39362258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_X: 394e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, src_reg); 39562258278SAlexei Starovoitov break; 39662258278SAlexei Starovoitov 397e430f34eSAlexei Starovoitov /* mov32 dst, src */ 39862258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_X: 399e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 400e430f34eSAlexei Starovoitov EMIT1(add_2mod(0x40, dst_reg, src_reg)); 401e430f34eSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg)); 40262258278SAlexei Starovoitov break; 40362258278SAlexei Starovoitov 404e430f34eSAlexei Starovoitov /* neg dst */ 40562258278SAlexei Starovoitov case BPF_ALU | BPF_NEG: 40662258278SAlexei Starovoitov case BPF_ALU64 | BPF_NEG: 40762258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 408e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 409e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 410e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 411e430f34eSAlexei Starovoitov EMIT2(0xF7, add_1reg(0xD8, dst_reg)); 41262258278SAlexei Starovoitov break; 41362258278SAlexei Starovoitov 41462258278SAlexei Starovoitov case BPF_ALU | BPF_ADD | BPF_K: 41562258278SAlexei Starovoitov case BPF_ALU | BPF_SUB | BPF_K: 41662258278SAlexei Starovoitov case BPF_ALU | BPF_AND | BPF_K: 41762258278SAlexei Starovoitov case BPF_ALU | BPF_OR | BPF_K: 41862258278SAlexei Starovoitov case BPF_ALU | BPF_XOR | BPF_K: 41962258278SAlexei Starovoitov case BPF_ALU64 | BPF_ADD | BPF_K: 42062258278SAlexei Starovoitov case BPF_ALU64 | BPF_SUB | BPF_K: 42162258278SAlexei Starovoitov case BPF_ALU64 | BPF_AND | BPF_K: 42262258278SAlexei Starovoitov case BPF_ALU64 | BPF_OR | BPF_K: 42362258278SAlexei Starovoitov case BPF_ALU64 | BPF_XOR | BPF_K: 42462258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 425e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 426e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 427e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 42862258278SAlexei Starovoitov 42962258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 43062258278SAlexei Starovoitov case BPF_ADD: b3 = 0xC0; break; 43162258278SAlexei Starovoitov case BPF_SUB: b3 = 0xE8; break; 43262258278SAlexei Starovoitov case BPF_AND: b3 = 0xE0; break; 43362258278SAlexei Starovoitov case BPF_OR: b3 = 0xC8; break; 43462258278SAlexei Starovoitov case BPF_XOR: b3 = 0xF0; break; 43562258278SAlexei Starovoitov } 43662258278SAlexei Starovoitov 437e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 438e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(b3, dst_reg), imm32); 43962258278SAlexei Starovoitov else 440e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32); 44162258278SAlexei Starovoitov break; 44262258278SAlexei Starovoitov 44362258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOV | BPF_K: 44462258278SAlexei Starovoitov /* optimization: if imm32 is positive, 44562258278SAlexei Starovoitov * use 'mov eax, imm32' (which zero-extends imm32) 44662258278SAlexei Starovoitov * to save 2 bytes 447d00a9dd2SEric Dumazet */ 448e430f34eSAlexei Starovoitov if (imm32 < 0) { 44962258278SAlexei Starovoitov /* 'mov rax, imm32' sign extends imm32 */ 450e430f34eSAlexei Starovoitov b1 = add_1mod(0x48, dst_reg); 45162258278SAlexei Starovoitov b2 = 0xC7; 45262258278SAlexei Starovoitov b3 = 0xC0; 453e430f34eSAlexei Starovoitov EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32); 454aee636c4SEric Dumazet break; 455aee636c4SEric Dumazet } 4563b58908aSEric Dumazet 45762258278SAlexei Starovoitov case BPF_ALU | BPF_MOV | BPF_K: 45862258278SAlexei Starovoitov /* mov %eax, imm32 */ 459e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 460e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 461e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0xB8, dst_reg), imm32); 46262258278SAlexei Starovoitov break; 46362258278SAlexei Starovoitov 46402ab695bSAlexei Starovoitov case BPF_LD | BPF_IMM | BPF_DW: 46502ab695bSAlexei Starovoitov if (insn[1].code != 0 || insn[1].src_reg != 0 || 46602ab695bSAlexei Starovoitov insn[1].dst_reg != 0 || insn[1].off != 0) { 46702ab695bSAlexei Starovoitov /* verifier must catch invalid insns */ 46802ab695bSAlexei Starovoitov pr_err("invalid BPF_LD_IMM64 insn\n"); 46902ab695bSAlexei Starovoitov return -EINVAL; 47002ab695bSAlexei Starovoitov } 47102ab695bSAlexei Starovoitov 47202ab695bSAlexei Starovoitov /* movabsq %rax, imm64 */ 47302ab695bSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg)); 47402ab695bSAlexei Starovoitov EMIT(insn[0].imm, 4); 47502ab695bSAlexei Starovoitov EMIT(insn[1].imm, 4); 47602ab695bSAlexei Starovoitov 47702ab695bSAlexei Starovoitov insn++; 47802ab695bSAlexei Starovoitov i++; 47902ab695bSAlexei Starovoitov break; 48002ab695bSAlexei Starovoitov 481e430f34eSAlexei Starovoitov /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */ 48262258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_X: 48362258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_X: 48462258278SAlexei Starovoitov case BPF_ALU | BPF_MOD | BPF_K: 48562258278SAlexei Starovoitov case BPF_ALU | BPF_DIV | BPF_K: 48662258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_X: 48762258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_X: 48862258278SAlexei Starovoitov case BPF_ALU64 | BPF_MOD | BPF_K: 48962258278SAlexei Starovoitov case BPF_ALU64 | BPF_DIV | BPF_K: 49062258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 49162258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 49262258278SAlexei Starovoitov 49362258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 494e430f34eSAlexei Starovoitov /* mov r11, src_reg */ 495e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, src_reg); 49662258278SAlexei Starovoitov else 497e430f34eSAlexei Starovoitov /* mov r11, imm32 */ 498e430f34eSAlexei Starovoitov EMIT3_off32(0x49, 0xC7, 0xC3, imm32); 49962258278SAlexei Starovoitov 500e430f34eSAlexei Starovoitov /* mov rax, dst_reg */ 501e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, dst_reg); 50262258278SAlexei Starovoitov 50362258278SAlexei Starovoitov /* xor edx, edx 50462258278SAlexei Starovoitov * equivalent to 'xor rdx, rdx', but one byte less 50562258278SAlexei Starovoitov */ 50662258278SAlexei Starovoitov EMIT2(0x31, 0xd2); 50762258278SAlexei Starovoitov 50862258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) { 509e430f34eSAlexei Starovoitov /* if (src_reg == 0) return 0 */ 51062258278SAlexei Starovoitov 51162258278SAlexei Starovoitov /* cmp r11, 0 */ 51262258278SAlexei Starovoitov EMIT4(0x49, 0x83, 0xFB, 0x00); 51362258278SAlexei Starovoitov 51462258278SAlexei Starovoitov /* jne .+9 (skip over pop, pop, xor and jmp) */ 51562258278SAlexei Starovoitov EMIT2(X86_JNE, 1 + 1 + 2 + 5); 51662258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 51762258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 51862258278SAlexei Starovoitov EMIT2(0x31, 0xc0); /* xor eax, eax */ 51962258278SAlexei Starovoitov 52062258278SAlexei Starovoitov /* jmp cleanup_addr 52162258278SAlexei Starovoitov * addrs[i] - 11, because there are 11 bytes 52262258278SAlexei Starovoitov * after this insn: div, mov, pop, pop, mov 52362258278SAlexei Starovoitov */ 52462258278SAlexei Starovoitov jmp_offset = ctx->cleanup_addr - (addrs[i] - 11); 52562258278SAlexei Starovoitov EMIT1_off32(0xE9, jmp_offset); 52662258278SAlexei Starovoitov } 52762258278SAlexei Starovoitov 52862258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 52962258278SAlexei Starovoitov /* div r11 */ 53062258278SAlexei Starovoitov EMIT3(0x49, 0xF7, 0xF3); 53162258278SAlexei Starovoitov else 53262258278SAlexei Starovoitov /* div r11d */ 53362258278SAlexei Starovoitov EMIT3(0x41, 0xF7, 0xF3); 53462258278SAlexei Starovoitov 53562258278SAlexei Starovoitov if (BPF_OP(insn->code) == BPF_MOD) 53662258278SAlexei Starovoitov /* mov r11, rdx */ 53762258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xD3); 53862258278SAlexei Starovoitov else 53962258278SAlexei Starovoitov /* mov r11, rax */ 54062258278SAlexei Starovoitov EMIT3(0x49, 0x89, 0xC3); 54162258278SAlexei Starovoitov 54262258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 54362258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 54462258278SAlexei Starovoitov 545e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 546e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 54762258278SAlexei Starovoitov break; 54862258278SAlexei Starovoitov 54962258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_K: 55062258278SAlexei Starovoitov case BPF_ALU | BPF_MUL | BPF_X: 55162258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_K: 55262258278SAlexei Starovoitov case BPF_ALU64 | BPF_MUL | BPF_X: 55362258278SAlexei Starovoitov EMIT1(0x50); /* push rax */ 55462258278SAlexei Starovoitov EMIT1(0x52); /* push rdx */ 55562258278SAlexei Starovoitov 556e430f34eSAlexei Starovoitov /* mov r11, dst_reg */ 557e430f34eSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 55862258278SAlexei Starovoitov 55962258278SAlexei Starovoitov if (BPF_SRC(insn->code) == BPF_X) 560e430f34eSAlexei Starovoitov /* mov rax, src_reg */ 561e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_0, src_reg); 56262258278SAlexei Starovoitov else 563e430f34eSAlexei Starovoitov /* mov rax, imm32 */ 564e430f34eSAlexei Starovoitov EMIT3_off32(0x48, 0xC7, 0xC0, imm32); 56562258278SAlexei Starovoitov 56662258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 56762258278SAlexei Starovoitov EMIT1(add_1mod(0x48, AUX_REG)); 56862258278SAlexei Starovoitov else if (is_ereg(AUX_REG)) 56962258278SAlexei Starovoitov EMIT1(add_1mod(0x40, AUX_REG)); 57062258278SAlexei Starovoitov /* mul(q) r11 */ 57162258278SAlexei Starovoitov EMIT2(0xF7, add_1reg(0xE0, AUX_REG)); 57262258278SAlexei Starovoitov 57362258278SAlexei Starovoitov /* mov r11, rax */ 57462258278SAlexei Starovoitov EMIT_mov(AUX_REG, BPF_REG_0); 57562258278SAlexei Starovoitov 57662258278SAlexei Starovoitov EMIT1(0x5A); /* pop rdx */ 57762258278SAlexei Starovoitov EMIT1(0x58); /* pop rax */ 57862258278SAlexei Starovoitov 579e430f34eSAlexei Starovoitov /* mov dst_reg, r11 */ 580e430f34eSAlexei Starovoitov EMIT_mov(dst_reg, AUX_REG); 58162258278SAlexei Starovoitov break; 58262258278SAlexei Starovoitov 58362258278SAlexei Starovoitov /* shifts */ 58462258278SAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_K: 58562258278SAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_K: 58662258278SAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_K: 58762258278SAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_K: 58862258278SAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_K: 58962258278SAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_K: 59062258278SAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 591e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 592e430f34eSAlexei Starovoitov else if (is_ereg(dst_reg)) 593e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 59462258278SAlexei Starovoitov 59562258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 59662258278SAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 59762258278SAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 59862258278SAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 59962258278SAlexei Starovoitov } 600e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(b3, dst_reg), imm32); 60162258278SAlexei Starovoitov break; 60262258278SAlexei Starovoitov 60372b603eeSAlexei Starovoitov case BPF_ALU | BPF_LSH | BPF_X: 60472b603eeSAlexei Starovoitov case BPF_ALU | BPF_RSH | BPF_X: 60572b603eeSAlexei Starovoitov case BPF_ALU | BPF_ARSH | BPF_X: 60672b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_LSH | BPF_X: 60772b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_RSH | BPF_X: 60872b603eeSAlexei Starovoitov case BPF_ALU64 | BPF_ARSH | BPF_X: 60972b603eeSAlexei Starovoitov 61072b603eeSAlexei Starovoitov /* check for bad case when dst_reg == rcx */ 61172b603eeSAlexei Starovoitov if (dst_reg == BPF_REG_4) { 61272b603eeSAlexei Starovoitov /* mov r11, dst_reg */ 61372b603eeSAlexei Starovoitov EMIT_mov(AUX_REG, dst_reg); 61472b603eeSAlexei Starovoitov dst_reg = AUX_REG; 61572b603eeSAlexei Starovoitov } 61672b603eeSAlexei Starovoitov 61772b603eeSAlexei Starovoitov if (src_reg != BPF_REG_4) { /* common case */ 61872b603eeSAlexei Starovoitov EMIT1(0x51); /* push rcx */ 61972b603eeSAlexei Starovoitov 62072b603eeSAlexei Starovoitov /* mov rcx, src_reg */ 62172b603eeSAlexei Starovoitov EMIT_mov(BPF_REG_4, src_reg); 62272b603eeSAlexei Starovoitov } 62372b603eeSAlexei Starovoitov 62472b603eeSAlexei Starovoitov /* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */ 62572b603eeSAlexei Starovoitov if (BPF_CLASS(insn->code) == BPF_ALU64) 62672b603eeSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 62772b603eeSAlexei Starovoitov else if (is_ereg(dst_reg)) 62872b603eeSAlexei Starovoitov EMIT1(add_1mod(0x40, dst_reg)); 62972b603eeSAlexei Starovoitov 63072b603eeSAlexei Starovoitov switch (BPF_OP(insn->code)) { 63172b603eeSAlexei Starovoitov case BPF_LSH: b3 = 0xE0; break; 63272b603eeSAlexei Starovoitov case BPF_RSH: b3 = 0xE8; break; 63372b603eeSAlexei Starovoitov case BPF_ARSH: b3 = 0xF8; break; 63472b603eeSAlexei Starovoitov } 63572b603eeSAlexei Starovoitov EMIT2(0xD3, add_1reg(b3, dst_reg)); 63672b603eeSAlexei Starovoitov 63772b603eeSAlexei Starovoitov if (src_reg != BPF_REG_4) 63872b603eeSAlexei Starovoitov EMIT1(0x59); /* pop rcx */ 63972b603eeSAlexei Starovoitov 64072b603eeSAlexei Starovoitov if (insn->dst_reg == BPF_REG_4) 64172b603eeSAlexei Starovoitov /* mov dst_reg, r11 */ 64272b603eeSAlexei Starovoitov EMIT_mov(insn->dst_reg, AUX_REG); 64372b603eeSAlexei Starovoitov break; 64472b603eeSAlexei Starovoitov 64562258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_BE: 646e430f34eSAlexei Starovoitov switch (imm32) { 64762258278SAlexei Starovoitov case 16: 64862258278SAlexei Starovoitov /* emit 'ror %ax, 8' to swap lower 2 bytes */ 64962258278SAlexei Starovoitov EMIT1(0x66); 650e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 65162258278SAlexei Starovoitov EMIT1(0x41); 652e430f34eSAlexei Starovoitov EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8); 653343f845bSAlexei Starovoitov 654343f845bSAlexei Starovoitov /* emit 'movzwl eax, ax' */ 655343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 656343f845bSAlexei Starovoitov EMIT3(0x45, 0x0F, 0xB7); 657343f845bSAlexei Starovoitov else 658343f845bSAlexei Starovoitov EMIT2(0x0F, 0xB7); 659343f845bSAlexei Starovoitov EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 66062258278SAlexei Starovoitov break; 66162258278SAlexei Starovoitov case 32: 66262258278SAlexei Starovoitov /* emit 'bswap eax' to swap lower 4 bytes */ 663e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 66462258278SAlexei Starovoitov EMIT2(0x41, 0x0F); 66562258278SAlexei Starovoitov else 66662258278SAlexei Starovoitov EMIT1(0x0F); 667e430f34eSAlexei Starovoitov EMIT1(add_1reg(0xC8, dst_reg)); 66862258278SAlexei Starovoitov break; 66962258278SAlexei Starovoitov case 64: 67062258278SAlexei Starovoitov /* emit 'bswap rax' to swap 8 bytes */ 671e430f34eSAlexei Starovoitov EMIT3(add_1mod(0x48, dst_reg), 0x0F, 672e430f34eSAlexei Starovoitov add_1reg(0xC8, dst_reg)); 67362258278SAlexei Starovoitov break; 67462258278SAlexei Starovoitov } 67562258278SAlexei Starovoitov break; 67662258278SAlexei Starovoitov 67762258278SAlexei Starovoitov case BPF_ALU | BPF_END | BPF_FROM_LE: 678343f845bSAlexei Starovoitov switch (imm32) { 679343f845bSAlexei Starovoitov case 16: 680343f845bSAlexei Starovoitov /* emit 'movzwl eax, ax' to zero extend 16-bit 681343f845bSAlexei Starovoitov * into 64 bit 682343f845bSAlexei Starovoitov */ 683343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 684343f845bSAlexei Starovoitov EMIT3(0x45, 0x0F, 0xB7); 685343f845bSAlexei Starovoitov else 686343f845bSAlexei Starovoitov EMIT2(0x0F, 0xB7); 687343f845bSAlexei Starovoitov EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 688343f845bSAlexei Starovoitov break; 689343f845bSAlexei Starovoitov case 32: 690343f845bSAlexei Starovoitov /* emit 'mov eax, eax' to clear upper 32-bits */ 691343f845bSAlexei Starovoitov if (is_ereg(dst_reg)) 692343f845bSAlexei Starovoitov EMIT1(0x45); 693343f845bSAlexei Starovoitov EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg)); 694343f845bSAlexei Starovoitov break; 695343f845bSAlexei Starovoitov case 64: 696343f845bSAlexei Starovoitov /* nop */ 697343f845bSAlexei Starovoitov break; 698343f845bSAlexei Starovoitov } 69962258278SAlexei Starovoitov break; 70062258278SAlexei Starovoitov 701e430f34eSAlexei Starovoitov /* ST: *(u8*)(dst_reg + off) = imm */ 70262258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_B: 703e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 70462258278SAlexei Starovoitov EMIT2(0x41, 0xC6); 70562258278SAlexei Starovoitov else 70662258278SAlexei Starovoitov EMIT1(0xC6); 70762258278SAlexei Starovoitov goto st; 70862258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_H: 709e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 71062258278SAlexei Starovoitov EMIT3(0x66, 0x41, 0xC7); 71162258278SAlexei Starovoitov else 71262258278SAlexei Starovoitov EMIT2(0x66, 0xC7); 71362258278SAlexei Starovoitov goto st; 71462258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_W: 715e430f34eSAlexei Starovoitov if (is_ereg(dst_reg)) 71662258278SAlexei Starovoitov EMIT2(0x41, 0xC7); 71762258278SAlexei Starovoitov else 71862258278SAlexei Starovoitov EMIT1(0xC7); 71962258278SAlexei Starovoitov goto st; 72062258278SAlexei Starovoitov case BPF_ST | BPF_MEM | BPF_DW: 721e430f34eSAlexei Starovoitov EMIT2(add_1mod(0x48, dst_reg), 0xC7); 72262258278SAlexei Starovoitov 72362258278SAlexei Starovoitov st: if (is_imm8(insn->off)) 724e430f34eSAlexei Starovoitov EMIT2(add_1reg(0x40, dst_reg), insn->off); 72562258278SAlexei Starovoitov else 726e430f34eSAlexei Starovoitov EMIT1_off32(add_1reg(0x80, dst_reg), insn->off); 72762258278SAlexei Starovoitov 728e430f34eSAlexei Starovoitov EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code))); 72962258278SAlexei Starovoitov break; 73062258278SAlexei Starovoitov 731e430f34eSAlexei Starovoitov /* STX: *(u8*)(dst_reg + off) = src_reg */ 73262258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_B: 73362258278SAlexei Starovoitov /* emit 'mov byte ptr [rax + off], al' */ 734e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg) || 73562258278SAlexei Starovoitov /* have to add extra byte for x86 SIL, DIL regs */ 736e430f34eSAlexei Starovoitov src_reg == BPF_REG_1 || src_reg == BPF_REG_2) 737e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88); 73862258278SAlexei Starovoitov else 73962258278SAlexei Starovoitov EMIT1(0x88); 74062258278SAlexei Starovoitov goto stx; 74162258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_H: 742e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 743e430f34eSAlexei Starovoitov EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89); 74462258278SAlexei Starovoitov else 74562258278SAlexei Starovoitov EMIT2(0x66, 0x89); 74662258278SAlexei Starovoitov goto stx; 74762258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_W: 748e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 749e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89); 75062258278SAlexei Starovoitov else 75162258278SAlexei Starovoitov EMIT1(0x89); 75262258278SAlexei Starovoitov goto stx; 75362258278SAlexei Starovoitov case BPF_STX | BPF_MEM | BPF_DW: 754e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89); 75562258278SAlexei Starovoitov stx: if (is_imm8(insn->off)) 756e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 75762258278SAlexei Starovoitov else 758e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 75962258278SAlexei Starovoitov insn->off); 76062258278SAlexei Starovoitov break; 76162258278SAlexei Starovoitov 762e430f34eSAlexei Starovoitov /* LDX: dst_reg = *(u8*)(src_reg + off) */ 76362258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_B: 76462258278SAlexei Starovoitov /* emit 'movzx rax, byte ptr [rax + off]' */ 765e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6); 76662258278SAlexei Starovoitov goto ldx; 76762258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_H: 76862258278SAlexei Starovoitov /* emit 'movzx rax, word ptr [rax + off]' */ 769e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7); 77062258278SAlexei Starovoitov goto ldx; 77162258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_W: 77262258278SAlexei Starovoitov /* emit 'mov eax, dword ptr [rax+0x14]' */ 773e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 774e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B); 77562258278SAlexei Starovoitov else 77662258278SAlexei Starovoitov EMIT1(0x8B); 77762258278SAlexei Starovoitov goto ldx; 77862258278SAlexei Starovoitov case BPF_LDX | BPF_MEM | BPF_DW: 77962258278SAlexei Starovoitov /* emit 'mov rax, qword ptr [rax+0x14]' */ 780e430f34eSAlexei Starovoitov EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B); 78162258278SAlexei Starovoitov ldx: /* if insn->off == 0 we can save one extra byte, but 78262258278SAlexei Starovoitov * special case of x86 r13 which always needs an offset 78362258278SAlexei Starovoitov * is not worth the hassle 78462258278SAlexei Starovoitov */ 78562258278SAlexei Starovoitov if (is_imm8(insn->off)) 786e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off); 78762258278SAlexei Starovoitov else 788e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), 78962258278SAlexei Starovoitov insn->off); 79062258278SAlexei Starovoitov break; 79162258278SAlexei Starovoitov 792e430f34eSAlexei Starovoitov /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */ 79362258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_W: 79462258278SAlexei Starovoitov /* emit 'lock add dword ptr [rax + off], eax' */ 795e430f34eSAlexei Starovoitov if (is_ereg(dst_reg) || is_ereg(src_reg)) 796e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01); 79762258278SAlexei Starovoitov else 79862258278SAlexei Starovoitov EMIT2(0xF0, 0x01); 79962258278SAlexei Starovoitov goto xadd; 80062258278SAlexei Starovoitov case BPF_STX | BPF_XADD | BPF_DW: 801e430f34eSAlexei Starovoitov EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01); 80262258278SAlexei Starovoitov xadd: if (is_imm8(insn->off)) 803e430f34eSAlexei Starovoitov EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 80462258278SAlexei Starovoitov else 805e430f34eSAlexei Starovoitov EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 80662258278SAlexei Starovoitov insn->off); 80762258278SAlexei Starovoitov break; 80862258278SAlexei Starovoitov 80962258278SAlexei Starovoitov /* call */ 81062258278SAlexei Starovoitov case BPF_JMP | BPF_CALL: 811e430f34eSAlexei Starovoitov func = (u8 *) __bpf_call_base + imm32; 81262258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 813e0ee9c12SAlexei Starovoitov if (seen_ld_abs) { 8144e10df9aSAlexei Starovoitov reload_skb_data = bpf_helper_changes_skb_data(func); 8154e10df9aSAlexei Starovoitov if (reload_skb_data) { 8164e10df9aSAlexei Starovoitov EMIT1(0x57); /* push %rdi */ 8174e10df9aSAlexei Starovoitov jmp_offset += 22; /* pop, mov, sub, mov */ 8184e10df9aSAlexei Starovoitov } else { 81962258278SAlexei Starovoitov EMIT2(0x41, 0x52); /* push %r10 */ 82062258278SAlexei Starovoitov EMIT2(0x41, 0x51); /* push %r9 */ 82162258278SAlexei Starovoitov /* need to adjust jmp offset, since 82262258278SAlexei Starovoitov * pop %r9, pop %r10 take 4 bytes after call insn 82362258278SAlexei Starovoitov */ 82462258278SAlexei Starovoitov jmp_offset += 4; 82562258278SAlexei Starovoitov } 8264e10df9aSAlexei Starovoitov } 827e430f34eSAlexei Starovoitov if (!imm32 || !is_simm32(jmp_offset)) { 82862258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 829e430f34eSAlexei Starovoitov imm32, func, image); 830f3c2af7bSAlexei Starovoitov return -EINVAL; 83162258278SAlexei Starovoitov } 83262258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); 833e0ee9c12SAlexei Starovoitov if (seen_ld_abs) { 8344e10df9aSAlexei Starovoitov if (reload_skb_data) { 8354e10df9aSAlexei Starovoitov EMIT1(0x5F); /* pop %rdi */ 8364e10df9aSAlexei Starovoitov emit_load_skb_data_hlen(&prog); 8374e10df9aSAlexei Starovoitov } else { 83862258278SAlexei Starovoitov EMIT2(0x41, 0x59); /* pop %r9 */ 83962258278SAlexei Starovoitov EMIT2(0x41, 0x5A); /* pop %r10 */ 84062258278SAlexei Starovoitov } 8414e10df9aSAlexei Starovoitov } 84262258278SAlexei Starovoitov break; 84362258278SAlexei Starovoitov 844b52f00e6SAlexei Starovoitov case BPF_JMP | BPF_CALL | BPF_X: 845b52f00e6SAlexei Starovoitov emit_bpf_tail_call(&prog); 846b52f00e6SAlexei Starovoitov break; 847b52f00e6SAlexei Starovoitov 84862258278SAlexei Starovoitov /* cond jump */ 84962258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_X: 85062258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_X: 85162258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_X: 85262258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_X: 85362258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_X: 85462258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_X: 855e430f34eSAlexei Starovoitov /* cmp dst_reg, src_reg */ 856e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39, 857e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 85862258278SAlexei Starovoitov goto emit_cond_jmp; 85962258278SAlexei Starovoitov 86062258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_X: 861e430f34eSAlexei Starovoitov /* test dst_reg, src_reg */ 862e430f34eSAlexei Starovoitov EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x85, 863e430f34eSAlexei Starovoitov add_2reg(0xC0, dst_reg, src_reg)); 86462258278SAlexei Starovoitov goto emit_cond_jmp; 86562258278SAlexei Starovoitov 86662258278SAlexei Starovoitov case BPF_JMP | BPF_JSET | BPF_K: 867e430f34eSAlexei Starovoitov /* test dst_reg, imm32 */ 868e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 869e430f34eSAlexei Starovoitov EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32); 87062258278SAlexei Starovoitov goto emit_cond_jmp; 87162258278SAlexei Starovoitov 87262258278SAlexei Starovoitov case BPF_JMP | BPF_JEQ | BPF_K: 87362258278SAlexei Starovoitov case BPF_JMP | BPF_JNE | BPF_K: 87462258278SAlexei Starovoitov case BPF_JMP | BPF_JGT | BPF_K: 87562258278SAlexei Starovoitov case BPF_JMP | BPF_JGE | BPF_K: 87662258278SAlexei Starovoitov case BPF_JMP | BPF_JSGT | BPF_K: 87762258278SAlexei Starovoitov case BPF_JMP | BPF_JSGE | BPF_K: 878e430f34eSAlexei Starovoitov /* cmp dst_reg, imm8/32 */ 879e430f34eSAlexei Starovoitov EMIT1(add_1mod(0x48, dst_reg)); 88062258278SAlexei Starovoitov 881e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 882e430f34eSAlexei Starovoitov EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32); 88362258278SAlexei Starovoitov else 884e430f34eSAlexei Starovoitov EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32); 88562258278SAlexei Starovoitov 88662258278SAlexei Starovoitov emit_cond_jmp: /* convert BPF opcode to x86 */ 88762258278SAlexei Starovoitov switch (BPF_OP(insn->code)) { 88862258278SAlexei Starovoitov case BPF_JEQ: 88962258278SAlexei Starovoitov jmp_cond = X86_JE; 89062258278SAlexei Starovoitov break; 89162258278SAlexei Starovoitov case BPF_JSET: 89262258278SAlexei Starovoitov case BPF_JNE: 89362258278SAlexei Starovoitov jmp_cond = X86_JNE; 89462258278SAlexei Starovoitov break; 89562258278SAlexei Starovoitov case BPF_JGT: 89662258278SAlexei Starovoitov /* GT is unsigned '>', JA in x86 */ 89762258278SAlexei Starovoitov jmp_cond = X86_JA; 89862258278SAlexei Starovoitov break; 89962258278SAlexei Starovoitov case BPF_JGE: 90062258278SAlexei Starovoitov /* GE is unsigned '>=', JAE in x86 */ 90162258278SAlexei Starovoitov jmp_cond = X86_JAE; 90262258278SAlexei Starovoitov break; 90362258278SAlexei Starovoitov case BPF_JSGT: 90462258278SAlexei Starovoitov /* signed '>', GT in x86 */ 90562258278SAlexei Starovoitov jmp_cond = X86_JG; 90662258278SAlexei Starovoitov break; 90762258278SAlexei Starovoitov case BPF_JSGE: 90862258278SAlexei Starovoitov /* signed '>=', GE in x86 */ 90962258278SAlexei Starovoitov jmp_cond = X86_JGE; 91062258278SAlexei Starovoitov break; 91162258278SAlexei Starovoitov default: /* to silence gcc warning */ 91262258278SAlexei Starovoitov return -EFAULT; 91362258278SAlexei Starovoitov } 91462258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 91562258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 91662258278SAlexei Starovoitov EMIT2(jmp_cond, jmp_offset); 91762258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 91862258278SAlexei Starovoitov EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset); 9193b58908aSEric Dumazet } else { 92062258278SAlexei Starovoitov pr_err("cond_jmp gen bug %llx\n", jmp_offset); 92162258278SAlexei Starovoitov return -EFAULT; 9223b58908aSEric Dumazet } 92362258278SAlexei Starovoitov 9243b58908aSEric Dumazet break; 92562258278SAlexei Starovoitov 92662258278SAlexei Starovoitov case BPF_JMP | BPF_JA: 92762258278SAlexei Starovoitov jmp_offset = addrs[i + insn->off] - addrs[i]; 92862258278SAlexei Starovoitov if (!jmp_offset) 92962258278SAlexei Starovoitov /* optimize out nop jumps */ 93062258278SAlexei Starovoitov break; 93162258278SAlexei Starovoitov emit_jmp: 93262258278SAlexei Starovoitov if (is_imm8(jmp_offset)) { 93362258278SAlexei Starovoitov EMIT2(0xEB, jmp_offset); 93462258278SAlexei Starovoitov } else if (is_simm32(jmp_offset)) { 93562258278SAlexei Starovoitov EMIT1_off32(0xE9, jmp_offset); 93662258278SAlexei Starovoitov } else { 93762258278SAlexei Starovoitov pr_err("jmp gen bug %llx\n", jmp_offset); 93862258278SAlexei Starovoitov return -EFAULT; 9393b58908aSEric Dumazet } 94062258278SAlexei Starovoitov break; 94162258278SAlexei Starovoitov 94262258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_W: 94362258278SAlexei Starovoitov func = sk_load_word; 94462258278SAlexei Starovoitov goto common_load; 94562258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_W: 946e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_word); 947e0ee9c12SAlexei Starovoitov common_load: 948e0ee9c12SAlexei Starovoitov ctx->seen_ld_abs = seen_ld_abs = true; 94962258278SAlexei Starovoitov jmp_offset = func - (image + addrs[i]); 95062258278SAlexei Starovoitov if (!func || !is_simm32(jmp_offset)) { 95162258278SAlexei Starovoitov pr_err("unsupported bpf func %d addr %p image %p\n", 952e430f34eSAlexei Starovoitov imm32, func, image); 95362258278SAlexei Starovoitov return -EINVAL; 95462258278SAlexei Starovoitov } 95562258278SAlexei Starovoitov if (BPF_MODE(insn->code) == BPF_ABS) { 95662258278SAlexei Starovoitov /* mov %esi, imm32 */ 957e430f34eSAlexei Starovoitov EMIT1_off32(0xBE, imm32); 95862258278SAlexei Starovoitov } else { 959e430f34eSAlexei Starovoitov /* mov %rsi, src_reg */ 960e430f34eSAlexei Starovoitov EMIT_mov(BPF_REG_2, src_reg); 961e430f34eSAlexei Starovoitov if (imm32) { 962e430f34eSAlexei Starovoitov if (is_imm8(imm32)) 96362258278SAlexei Starovoitov /* add %esi, imm8 */ 964e430f34eSAlexei Starovoitov EMIT3(0x83, 0xC6, imm32); 96562258278SAlexei Starovoitov else 96662258278SAlexei Starovoitov /* add %esi, imm32 */ 967e430f34eSAlexei Starovoitov EMIT2_off32(0x81, 0xC6, imm32); 96862258278SAlexei Starovoitov } 96962258278SAlexei Starovoitov } 97062258278SAlexei Starovoitov /* skb pointer is in R6 (%rbx), it will be copied into 97162258278SAlexei Starovoitov * %rdi if skb_copy_bits() call is necessary. 97262258278SAlexei Starovoitov * sk_load_* helpers also use %r10 and %r9d. 97362258278SAlexei Starovoitov * See bpf_jit.S 97462258278SAlexei Starovoitov */ 97562258278SAlexei Starovoitov EMIT1_off32(0xE8, jmp_offset); /* call */ 9760a14842fSEric Dumazet break; 97762258278SAlexei Starovoitov 97862258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_H: 97962258278SAlexei Starovoitov func = sk_load_half; 98062258278SAlexei Starovoitov goto common_load; 98162258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_H: 982e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_half); 9830a14842fSEric Dumazet goto common_load; 98462258278SAlexei Starovoitov case BPF_LD | BPF_IND | BPF_B: 98562258278SAlexei Starovoitov func = sk_load_byte; 98662258278SAlexei Starovoitov goto common_load; 98762258278SAlexei Starovoitov case BPF_LD | BPF_ABS | BPF_B: 988e430f34eSAlexei Starovoitov func = CHOOSE_LOAD_FUNC(imm32, sk_load_byte); 9890a14842fSEric Dumazet goto common_load; 9900a14842fSEric Dumazet 99162258278SAlexei Starovoitov case BPF_JMP | BPF_EXIT: 992769e0de6SAlexei Starovoitov if (seen_exit) { 99362258278SAlexei Starovoitov jmp_offset = ctx->cleanup_addr - addrs[i]; 99462258278SAlexei Starovoitov goto emit_jmp; 99562258278SAlexei Starovoitov } 996769e0de6SAlexei Starovoitov seen_exit = true; 99762258278SAlexei Starovoitov /* update cleanup_addr */ 99862258278SAlexei Starovoitov ctx->cleanup_addr = proglen; 99962258278SAlexei Starovoitov /* mov rbx, qword ptr [rbp-X] */ 1000b52f00e6SAlexei Starovoitov EMIT3_off32(0x48, 0x8B, 0x9D, -STACKSIZE); 100162258278SAlexei Starovoitov /* mov r13, qword ptr [rbp-X] */ 1002b52f00e6SAlexei Starovoitov EMIT3_off32(0x4C, 0x8B, 0xAD, -STACKSIZE + 8); 100362258278SAlexei Starovoitov /* mov r14, qword ptr [rbp-X] */ 1004b52f00e6SAlexei Starovoitov EMIT3_off32(0x4C, 0x8B, 0xB5, -STACKSIZE + 16); 100562258278SAlexei Starovoitov /* mov r15, qword ptr [rbp-X] */ 1006b52f00e6SAlexei Starovoitov EMIT3_off32(0x4C, 0x8B, 0xBD, -STACKSIZE + 24); 10070a14842fSEric Dumazet 100862258278SAlexei Starovoitov EMIT1(0xC9); /* leave */ 100962258278SAlexei Starovoitov EMIT1(0xC3); /* ret */ 10100a14842fSEric Dumazet break; 10110a14842fSEric Dumazet 10120a14842fSEric Dumazet default: 101362258278SAlexei Starovoitov /* By design x64 JIT should support all BPF instructions 101462258278SAlexei Starovoitov * This error will be seen if new instruction was added 101562258278SAlexei Starovoitov * to interpreter, but not to JIT 10167ae457c1SAlexei Starovoitov * or if there is junk in bpf_prog 101762258278SAlexei Starovoitov */ 101862258278SAlexei Starovoitov pr_err("bpf_jit: unknown opcode %02x\n", insn->code); 1019f3c2af7bSAlexei Starovoitov return -EINVAL; 10200a14842fSEric Dumazet } 102162258278SAlexei Starovoitov 10220a14842fSEric Dumazet ilen = prog - temp; 1023e0ee9c12SAlexei Starovoitov if (ilen > BPF_MAX_INSN_SIZE) { 1024e0ee9c12SAlexei Starovoitov pr_err("bpf_jit_compile fatal insn size error\n"); 1025e0ee9c12SAlexei Starovoitov return -EFAULT; 1026e0ee9c12SAlexei Starovoitov } 1027e0ee9c12SAlexei Starovoitov 10280a14842fSEric Dumazet if (image) { 10290a14842fSEric Dumazet if (unlikely(proglen + ilen > oldproglen)) { 103062258278SAlexei Starovoitov pr_err("bpf_jit_compile fatal error\n"); 1031f3c2af7bSAlexei Starovoitov return -EFAULT; 10320a14842fSEric Dumazet } 10330a14842fSEric Dumazet memcpy(image + proglen, temp, ilen); 10340a14842fSEric Dumazet } 10350a14842fSEric Dumazet proglen += ilen; 10360a14842fSEric Dumazet addrs[i] = proglen; 10370a14842fSEric Dumazet prog = temp; 10380a14842fSEric Dumazet } 1039f3c2af7bSAlexei Starovoitov return proglen; 1040f3c2af7bSAlexei Starovoitov } 1041f3c2af7bSAlexei Starovoitov 10427ae457c1SAlexei Starovoitov void bpf_jit_compile(struct bpf_prog *prog) 1043f3c2af7bSAlexei Starovoitov { 104462258278SAlexei Starovoitov } 104562258278SAlexei Starovoitov 10467ae457c1SAlexei Starovoitov void bpf_int_jit_compile(struct bpf_prog *prog) 104762258278SAlexei Starovoitov { 1048f3c2af7bSAlexei Starovoitov struct bpf_binary_header *header = NULL; 1049f3c2af7bSAlexei Starovoitov int proglen, oldproglen = 0; 1050f3c2af7bSAlexei Starovoitov struct jit_context ctx = {}; 1051f3c2af7bSAlexei Starovoitov u8 *image = NULL; 1052f3c2af7bSAlexei Starovoitov int *addrs; 1053f3c2af7bSAlexei Starovoitov int pass; 1054f3c2af7bSAlexei Starovoitov int i; 1055f3c2af7bSAlexei Starovoitov 1056f3c2af7bSAlexei Starovoitov if (!bpf_jit_enable) 1057f3c2af7bSAlexei Starovoitov return; 1058f3c2af7bSAlexei Starovoitov 1059f3c2af7bSAlexei Starovoitov if (!prog || !prog->len) 1060f3c2af7bSAlexei Starovoitov return; 1061f3c2af7bSAlexei Starovoitov 1062f3c2af7bSAlexei Starovoitov addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL); 1063f3c2af7bSAlexei Starovoitov if (!addrs) 1064f3c2af7bSAlexei Starovoitov return; 1065f3c2af7bSAlexei Starovoitov 1066f3c2af7bSAlexei Starovoitov /* Before first pass, make a rough estimation of addrs[] 1067f3c2af7bSAlexei Starovoitov * each bpf instruction is translated to less than 64 bytes 1068f3c2af7bSAlexei Starovoitov */ 1069f3c2af7bSAlexei Starovoitov for (proglen = 0, i = 0; i < prog->len; i++) { 1070f3c2af7bSAlexei Starovoitov proglen += 64; 1071f3c2af7bSAlexei Starovoitov addrs[i] = proglen; 1072f3c2af7bSAlexei Starovoitov } 1073f3c2af7bSAlexei Starovoitov ctx.cleanup_addr = proglen; 1074f3c2af7bSAlexei Starovoitov 10753f7352bfSAlexei Starovoitov /* JITed image shrinks with every pass and the loop iterates 10763f7352bfSAlexei Starovoitov * until the image stops shrinking. Very large bpf programs 10773f7352bfSAlexei Starovoitov * may converge on the last pass. In such case do one more 10783f7352bfSAlexei Starovoitov * pass to emit the final image 10793f7352bfSAlexei Starovoitov */ 10803f7352bfSAlexei Starovoitov for (pass = 0; pass < 10 || image; pass++) { 1081f3c2af7bSAlexei Starovoitov proglen = do_jit(prog, addrs, image, oldproglen, &ctx); 1082f3c2af7bSAlexei Starovoitov if (proglen <= 0) { 1083f3c2af7bSAlexei Starovoitov image = NULL; 1084f3c2af7bSAlexei Starovoitov if (header) 1085738cbe72SDaniel Borkmann bpf_jit_binary_free(header); 1086f3c2af7bSAlexei Starovoitov goto out; 1087f3c2af7bSAlexei Starovoitov } 10880a14842fSEric Dumazet if (image) { 1089e0ee9c12SAlexei Starovoitov if (proglen != oldproglen) { 1090f3c2af7bSAlexei Starovoitov pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", 1091f3c2af7bSAlexei Starovoitov proglen, oldproglen); 1092e0ee9c12SAlexei Starovoitov goto out; 1093e0ee9c12SAlexei Starovoitov } 10940a14842fSEric Dumazet break; 10950a14842fSEric Dumazet } 10960a14842fSEric Dumazet if (proglen == oldproglen) { 1097738cbe72SDaniel Borkmann header = bpf_jit_binary_alloc(proglen, &image, 1098738cbe72SDaniel Borkmann 1, jit_fill_hole); 1099314beb9bSEric Dumazet if (!header) 11000a14842fSEric Dumazet goto out; 11010a14842fSEric Dumazet } 11020a14842fSEric Dumazet oldproglen = proglen; 11030a14842fSEric Dumazet } 110479617801SDaniel Borkmann 11050a14842fSEric Dumazet if (bpf_jit_enable > 1) 1106485d6511SDaniel Borkmann bpf_jit_dump(prog->len, proglen, pass + 1, image); 11070a14842fSEric Dumazet 11080a14842fSEric Dumazet if (image) { 1109314beb9bSEric Dumazet bpf_flush_icache(header, image + proglen); 1110314beb9bSEric Dumazet set_memory_ro((unsigned long)header, header->pages); 1111f3c2af7bSAlexei Starovoitov prog->bpf_func = (void *)image; 1112286aad3cSDaniel Borkmann prog->jited = true; 11130a14842fSEric Dumazet } 11140a14842fSEric Dumazet out: 11150a14842fSEric Dumazet kfree(addrs); 11160a14842fSEric Dumazet } 11170a14842fSEric Dumazet 111860a3b225SDaniel Borkmann void bpf_jit_free(struct bpf_prog *fp) 11190a14842fSEric Dumazet { 1120314beb9bSEric Dumazet unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK; 1121314beb9bSEric Dumazet struct bpf_binary_header *header = (void *)addr; 1122314beb9bSEric Dumazet 112360a3b225SDaniel Borkmann if (!fp->jited) 112460a3b225SDaniel Borkmann goto free_filter; 112560a3b225SDaniel Borkmann 1126314beb9bSEric Dumazet set_memory_rw(addr, header->pages); 1127738cbe72SDaniel Borkmann bpf_jit_binary_free(header); 1128d45ed4a4SAlexei Starovoitov 112960a3b225SDaniel Borkmann free_filter: 113060a3b225SDaniel Borkmann bpf_prog_unlock_free(fp); 11310a14842fSEric Dumazet } 1132