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path: root/arch/arm/net/bpf_jit_32.c
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Diffstat (limited to 'arch/arm/net/bpf_jit_32.c')
-rw-r--r--arch/arm/net/bpf_jit_32.c197
1 files changed, 96 insertions, 101 deletions
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index a34f1e21411..fb5503ce016 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -19,6 +19,7 @@
#include <linux/if_vlan.h>
#include <asm/cacheflush.h>
#include <asm/hwcap.h>
+#include <asm/opcodes.h>
#include "bpf_jit_32.h"
@@ -113,8 +114,11 @@ static u32 jit_udiv(u32 dividend, u32 divisor)
static inline void _emit(int cond, u32 inst, struct jit_ctx *ctx)
{
+ inst |= (cond << 28);
+ inst = __opcode_to_mem_arm(inst);
+
if (ctx->target != NULL)
- ctx->target[ctx->idx] = inst | (cond << 28);
+ ctx->target[ctx->idx] = inst;
ctx->idx++;
}
@@ -132,7 +136,7 @@ static u16 saved_regs(struct jit_ctx *ctx)
u16 ret = 0;
if ((ctx->skf->len > 1) ||
- (ctx->skf->insns[0].code == BPF_S_RET_A))
+ (ctx->skf->insns[0].code == (BPF_RET | BPF_A)))
ret |= 1 << r_A;
#ifdef CONFIG_FRAME_POINTER
@@ -160,18 +164,10 @@ static inline int mem_words_used(struct jit_ctx *ctx)
static inline bool is_load_to_a(u16 inst)
{
switch (inst) {
- case BPF_S_LD_W_LEN:
- case BPF_S_LD_W_ABS:
- case BPF_S_LD_H_ABS:
- case BPF_S_LD_B_ABS:
- case BPF_S_ANC_CPU:
- case BPF_S_ANC_IFINDEX:
- case BPF_S_ANC_MARK:
- case BPF_S_ANC_PROTOCOL:
- case BPF_S_ANC_RXHASH:
- case BPF_S_ANC_VLAN_TAG:
- case BPF_S_ANC_VLAN_TAG_PRESENT:
- case BPF_S_ANC_QUEUE:
+ case BPF_LD | BPF_W | BPF_LEN:
+ case BPF_LD | BPF_W | BPF_ABS:
+ case BPF_LD | BPF_H | BPF_ABS:
+ case BPF_LD | BPF_B | BPF_ABS:
return true;
default:
return false;
@@ -211,7 +207,7 @@ static void build_prologue(struct jit_ctx *ctx)
emit(ARM_MOV_I(r_X, 0), ctx);
/* do not leak kernel data to userspace */
- if ((first_inst != BPF_S_RET_K) && !(is_load_to_a(first_inst)))
+ if ((first_inst != (BPF_RET | BPF_K)) && !(is_load_to_a(first_inst)))
emit(ARM_MOV_I(r_A, 0), ctx);
/* stack space for the BPF_MEM words */
@@ -341,10 +337,17 @@ static void emit_load_be16(u8 cond, u8 r_res, u8 r_addr, struct jit_ctx *ctx)
static inline void emit_swap16(u8 r_dst, u8 r_src, struct jit_ctx *ctx)
{
- emit(ARM_LSL_R(ARM_R1, r_src, 8), ctx);
- emit(ARM_ORR_S(r_dst, ARM_R1, r_src, SRTYPE_LSL, 8), ctx);
- emit(ARM_LSL_I(r_dst, r_dst, 8), ctx);
- emit(ARM_LSL_R(r_dst, r_dst, 8), ctx);
+ /* r_dst = (r_src << 8) | (r_src >> 8) */
+ emit(ARM_LSL_I(ARM_R1, r_src, 8), ctx);
+ emit(ARM_ORR_S(r_dst, ARM_R1, r_src, SRTYPE_LSR, 8), ctx);
+
+ /*
+ * we need to mask out the bits set in r_dst[23:16] due to
+ * the first shift instruction.
+ *
+ * note that 0x8ff is the encoded immediate 0x00ff0000.
+ */
+ emit(ARM_BIC_I(r_dst, r_dst, 0x8ff), ctx);
}
#else /* ARMv6+ */
@@ -469,36 +472,39 @@ static int build_body(struct jit_ctx *ctx)
u32 k;
for (i = 0; i < prog->len; i++) {
+ u16 code;
+
inst = &(prog->insns[i]);
/* K as an immediate value operand */
k = inst->k;
+ code = bpf_anc_helper(inst);
/* compute offsets only in the fake pass */
if (ctx->target == NULL)
ctx->offsets[i] = ctx->idx * 4;
- switch (inst->code) {
- case BPF_S_LD_IMM:
+ switch (code) {
+ case BPF_LD | BPF_IMM:
emit_mov_i(r_A, k, ctx);
break;
- case BPF_S_LD_W_LEN:
+ case BPF_LD | BPF_W | BPF_LEN:
ctx->seen |= SEEN_SKB;
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, len) != 4);
emit(ARM_LDR_I(r_A, r_skb,
offsetof(struct sk_buff, len)), ctx);
break;
- case BPF_S_LD_MEM:
+ case BPF_LD | BPF_MEM:
/* A = scratch[k] */
ctx->seen |= SEEN_MEM_WORD(k);
emit(ARM_LDR_I(r_A, ARM_SP, SCRATCH_OFF(k)), ctx);
break;
- case BPF_S_LD_W_ABS:
+ case BPF_LD | BPF_W | BPF_ABS:
load_order = 2;
goto load;
- case BPF_S_LD_H_ABS:
+ case BPF_LD | BPF_H | BPF_ABS:
load_order = 1;
goto load;
- case BPF_S_LD_B_ABS:
+ case BPF_LD | BPF_B | BPF_ABS:
load_order = 0;
load:
/* the interpreter will deal with the negative K */
@@ -541,35 +547,35 @@ load_common:
emit_err_ret(ARM_COND_NE, ctx);
emit(ARM_MOV_R(r_A, ARM_R0), ctx);
break;
- case BPF_S_LD_W_IND:
+ case BPF_LD | BPF_W | BPF_IND:
load_order = 2;
goto load_ind;
- case BPF_S_LD_H_IND:
+ case BPF_LD | BPF_H | BPF_IND:
load_order = 1;
goto load_ind;
- case BPF_S_LD_B_IND:
+ case BPF_LD | BPF_B | BPF_IND:
load_order = 0;
load_ind:
OP_IMM3(ARM_ADD, r_off, r_X, k, ctx);
goto load_common;
- case BPF_S_LDX_IMM:
+ case BPF_LDX | BPF_IMM:
ctx->seen |= SEEN_X;
emit_mov_i(r_X, k, ctx);
break;
- case BPF_S_LDX_W_LEN:
+ case BPF_LDX | BPF_W | BPF_LEN:
ctx->seen |= SEEN_X | SEEN_SKB;
emit(ARM_LDR_I(r_X, r_skb,
offsetof(struct sk_buff, len)), ctx);
break;
- case BPF_S_LDX_MEM:
+ case BPF_LDX | BPF_MEM:
ctx->seen |= SEEN_X | SEEN_MEM_WORD(k);
emit(ARM_LDR_I(r_X, ARM_SP, SCRATCH_OFF(k)), ctx);
break;
- case BPF_S_LDX_B_MSH:
+ case BPF_LDX | BPF_B | BPF_MSH:
/* x = ((*(frame + k)) & 0xf) << 2; */
ctx->seen |= SEEN_X | SEEN_DATA | SEEN_CALL;
/* the interpreter should deal with the negative K */
- if (k < 0)
+ if ((int)k < 0)
return -1;
/* offset in r1: we might have to take the slow path */
emit_mov_i(r_off, k, ctx);
@@ -595,113 +601,113 @@ load_ind:
emit(ARM_AND_I(r_X, ARM_R0, 0x00f), ctx);
emit(ARM_LSL_I(r_X, r_X, 2), ctx);
break;
- case BPF_S_ST:
+ case BPF_ST:
ctx->seen |= SEEN_MEM_WORD(k);
emit(ARM_STR_I(r_A, ARM_SP, SCRATCH_OFF(k)), ctx);
break;
- case BPF_S_STX:
+ case BPF_STX:
update_on_xread(ctx);
ctx->seen |= SEEN_MEM_WORD(k);
emit(ARM_STR_I(r_X, ARM_SP, SCRATCH_OFF(k)), ctx);
break;
- case BPF_S_ALU_ADD_K:
+ case BPF_ALU | BPF_ADD | BPF_K:
/* A += K */
OP_IMM3(ARM_ADD, r_A, r_A, k, ctx);
break;
- case BPF_S_ALU_ADD_X:
+ case BPF_ALU | BPF_ADD | BPF_X:
update_on_xread(ctx);
emit(ARM_ADD_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_SUB_K:
+ case BPF_ALU | BPF_SUB | BPF_K:
/* A -= K */
OP_IMM3(ARM_SUB, r_A, r_A, k, ctx);
break;
- case BPF_S_ALU_SUB_X:
+ case BPF_ALU | BPF_SUB | BPF_X:
update_on_xread(ctx);
emit(ARM_SUB_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_MUL_K:
+ case BPF_ALU | BPF_MUL | BPF_K:
/* A *= K */
emit_mov_i(r_scratch, k, ctx);
emit(ARM_MUL(r_A, r_A, r_scratch), ctx);
break;
- case BPF_S_ALU_MUL_X:
+ case BPF_ALU | BPF_MUL | BPF_X:
update_on_xread(ctx);
emit(ARM_MUL(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_DIV_K:
- /* current k == reciprocal_value(userspace k) */
+ case BPF_ALU | BPF_DIV | BPF_K:
+ if (k == 1)
+ break;
emit_mov_i(r_scratch, k, ctx);
- /* A = top 32 bits of the product */
- emit(ARM_UMULL(r_scratch, r_A, r_A, r_scratch), ctx);
+ emit_udiv(r_A, r_A, r_scratch, ctx);
break;
- case BPF_S_ALU_DIV_X:
+ case BPF_ALU | BPF_DIV | BPF_X:
update_on_xread(ctx);
emit(ARM_CMP_I(r_X, 0), ctx);
emit_err_ret(ARM_COND_EQ, ctx);
emit_udiv(r_A, r_A, r_X, ctx);
break;
- case BPF_S_ALU_OR_K:
+ case BPF_ALU | BPF_OR | BPF_K:
/* A |= K */
OP_IMM3(ARM_ORR, r_A, r_A, k, ctx);
break;
- case BPF_S_ALU_OR_X:
+ case BPF_ALU | BPF_OR | BPF_X:
update_on_xread(ctx);
emit(ARM_ORR_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_XOR_K:
+ case BPF_ALU | BPF_XOR | BPF_K:
/* A ^= K; */
OP_IMM3(ARM_EOR, r_A, r_A, k, ctx);
break;
- case BPF_S_ANC_ALU_XOR_X:
- case BPF_S_ALU_XOR_X:
+ case BPF_ANC | SKF_AD_ALU_XOR_X:
+ case BPF_ALU | BPF_XOR | BPF_X:
/* A ^= X */
update_on_xread(ctx);
emit(ARM_EOR_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_AND_K:
+ case BPF_ALU | BPF_AND | BPF_K:
/* A &= K */
OP_IMM3(ARM_AND, r_A, r_A, k, ctx);
break;
- case BPF_S_ALU_AND_X:
+ case BPF_ALU | BPF_AND | BPF_X:
update_on_xread(ctx);
emit(ARM_AND_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_LSH_K:
+ case BPF_ALU | BPF_LSH | BPF_K:
if (unlikely(k > 31))
return -1;
emit(ARM_LSL_I(r_A, r_A, k), ctx);
break;
- case BPF_S_ALU_LSH_X:
+ case BPF_ALU | BPF_LSH | BPF_X:
update_on_xread(ctx);
emit(ARM_LSL_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_RSH_K:
+ case BPF_ALU | BPF_RSH | BPF_K:
if (unlikely(k > 31))
return -1;
emit(ARM_LSR_I(r_A, r_A, k), ctx);
break;
- case BPF_S_ALU_RSH_X:
+ case BPF_ALU | BPF_RSH | BPF_X:
update_on_xread(ctx);
emit(ARM_LSR_R(r_A, r_A, r_X), ctx);
break;
- case BPF_S_ALU_NEG:
+ case BPF_ALU | BPF_NEG:
/* A = -A */
emit(ARM_RSB_I(r_A, r_A, 0), ctx);
break;
- case BPF_S_JMP_JA:
+ case BPF_JMP | BPF_JA:
/* pc += K */
emit(ARM_B(b_imm(i + k + 1, ctx)), ctx);
break;
- case BPF_S_JMP_JEQ_K:
+ case BPF_JMP | BPF_JEQ | BPF_K:
/* pc += (A == K) ? pc->jt : pc->jf */
condt = ARM_COND_EQ;
goto cmp_imm;
- case BPF_S_JMP_JGT_K:
+ case BPF_JMP | BPF_JGT | BPF_K:
/* pc += (A > K) ? pc->jt : pc->jf */
condt = ARM_COND_HI;
goto cmp_imm;
- case BPF_S_JMP_JGE_K:
+ case BPF_JMP | BPF_JGE | BPF_K:
/* pc += (A >= K) ? pc->jt : pc->jf */
condt = ARM_COND_HS;
cmp_imm:
@@ -720,22 +726,22 @@ cond_jump:
_emit(condt ^ 1, ARM_B(b_imm(i + inst->jf + 1,
ctx)), ctx);
break;
- case BPF_S_JMP_JEQ_X:
+ case BPF_JMP | BPF_JEQ | BPF_X:
/* pc += (A == X) ? pc->jt : pc->jf */
condt = ARM_COND_EQ;
goto cmp_x;
- case BPF_S_JMP_JGT_X:
+ case BPF_JMP | BPF_JGT | BPF_X:
/* pc += (A > X) ? pc->jt : pc->jf */
condt = ARM_COND_HI;
goto cmp_x;
- case BPF_S_JMP_JGE_X:
+ case BPF_JMP | BPF_JGE | BPF_X:
/* pc += (A >= X) ? pc->jt : pc->jf */
condt = ARM_COND_CS;
cmp_x:
update_on_xread(ctx);
emit(ARM_CMP_R(r_A, r_X), ctx);
goto cond_jump;
- case BPF_S_JMP_JSET_K:
+ case BPF_JMP | BPF_JSET | BPF_K:
/* pc += (A & K) ? pc->jt : pc->jf */
condt = ARM_COND_NE;
/* not set iff all zeroes iff Z==1 iff EQ */
@@ -748,16 +754,16 @@ cmp_x:
emit(ARM_TST_I(r_A, imm12), ctx);
}
goto cond_jump;
- case BPF_S_JMP_JSET_X:
+ case BPF_JMP | BPF_JSET | BPF_X:
/* pc += (A & X) ? pc->jt : pc->jf */
update_on_xread(ctx);
condt = ARM_COND_NE;
emit(ARM_TST_R(r_A, r_X), ctx);
goto cond_jump;
- case BPF_S_RET_A:
+ case BPF_RET | BPF_A:
emit(ARM_MOV_R(ARM_R0, r_A), ctx);
goto b_epilogue;
- case BPF_S_RET_K:
+ case BPF_RET | BPF_K:
if ((k == 0) && (ctx->ret0_fp_idx < 0))
ctx->ret0_fp_idx = i;
emit_mov_i(ARM_R0, k, ctx);
@@ -765,17 +771,17 @@ b_epilogue:
if (i != ctx->skf->len - 1)
emit(ARM_B(b_imm(prog->len, ctx)), ctx);
break;
- case BPF_S_MISC_TAX:
+ case BPF_MISC | BPF_TAX:
/* X = A */
ctx->seen |= SEEN_X;
emit(ARM_MOV_R(r_X, r_A), ctx);
break;
- case BPF_S_MISC_TXA:
+ case BPF_MISC | BPF_TXA:
/* A = X */
update_on_xread(ctx);
emit(ARM_MOV_R(r_A, r_X), ctx);
break;
- case BPF_S_ANC_PROTOCOL:
+ case BPF_ANC | SKF_AD_PROTOCOL:
/* A = ntohs(skb->protocol) */
ctx->seen |= SEEN_SKB;
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff,
@@ -784,7 +790,7 @@ b_epilogue:
emit(ARM_LDRH_I(r_scratch, r_skb, off), ctx);
emit_swap16(r_A, r_scratch, ctx);
break;
- case BPF_S_ANC_CPU:
+ case BPF_ANC | SKF_AD_CPU:
/* r_scratch = current_thread_info() */
OP_IMM3(ARM_BIC, r_scratch, ARM_SP, THREAD_SIZE - 1, ctx);
/* A = current_thread_info()->cpu */
@@ -792,7 +798,7 @@ b_epilogue:
off = offsetof(struct thread_info, cpu);
emit(ARM_LDR_I(r_A, r_scratch, off), ctx);
break;
- case BPF_S_ANC_IFINDEX:
+ case BPF_ANC | SKF_AD_IFINDEX:
/* A = skb->dev->ifindex */
ctx->seen |= SEEN_SKB;
off = offsetof(struct sk_buff, dev);
@@ -806,30 +812,30 @@ b_epilogue:
off = offsetof(struct net_device, ifindex);
emit(ARM_LDR_I(r_A, r_scratch, off), ctx);
break;
- case BPF_S_ANC_MARK:
+ case BPF_ANC | SKF_AD_MARK:
ctx->seen |= SEEN_SKB;
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
off = offsetof(struct sk_buff, mark);
emit(ARM_LDR_I(r_A, r_skb, off), ctx);
break;
- case BPF_S_ANC_RXHASH:
+ case BPF_ANC | SKF_AD_RXHASH:
ctx->seen |= SEEN_SKB;
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, rxhash) != 4);
- off = offsetof(struct sk_buff, rxhash);
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
+ off = offsetof(struct sk_buff, hash);
emit(ARM_LDR_I(r_A, r_skb, off), ctx);
break;
- case BPF_S_ANC_VLAN_TAG:
- case BPF_S_ANC_VLAN_TAG_PRESENT:
+ case BPF_ANC | SKF_AD_VLAN_TAG:
+ case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
ctx->seen |= SEEN_SKB;
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
off = offsetof(struct sk_buff, vlan_tci);
emit(ARM_LDRH_I(r_A, r_skb, off), ctx);
- if (inst->code == BPF_S_ANC_VLAN_TAG)
+ if (code == (BPF_ANC | SKF_AD_VLAN_TAG))
OP_IMM3(ARM_AND, r_A, r_A, VLAN_VID_MASK, ctx);
else
OP_IMM3(ARM_AND, r_A, r_A, VLAN_TAG_PRESENT, ctx);
break;
- case BPF_S_ANC_QUEUE:
+ case BPF_ANC | SKF_AD_QUEUE:
ctx->seen |= SEEN_SKB;
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff,
queue_mapping) != 2);
@@ -893,8 +899,7 @@ void bpf_jit_compile(struct sk_filter *fp)
#endif
alloc_size = 4 * ctx.idx;
- ctx.target = module_alloc(max(sizeof(struct work_struct),
- alloc_size));
+ ctx.target = module_alloc(alloc_size);
if (unlikely(ctx.target == NULL))
goto out;
@@ -911,29 +916,19 @@ void bpf_jit_compile(struct sk_filter *fp)
#endif
if (bpf_jit_enable > 1)
- print_hex_dump(KERN_INFO, "BPF JIT code: ",
- DUMP_PREFIX_ADDRESS, 16, 4, ctx.target,
- alloc_size, false);
+ /* there are 2 passes here */
+ bpf_jit_dump(fp->len, alloc_size, 2, ctx.target);
fp->bpf_func = (void *)ctx.target;
+ fp->jited = 1;
out:
kfree(ctx.offsets);
return;
}
-static void bpf_jit_free_worker(struct work_struct *work)
-{
- module_free(NULL, work);
-}
-
void bpf_jit_free(struct sk_filter *fp)
{
- struct work_struct *work;
-
- if (fp->bpf_func != sk_run_filter) {
- work = (struct work_struct *)fp->bpf_func;
-
- INIT_WORK(work, bpf_jit_free_worker);
- schedule_work(work);
- }
+ if (fp->jited)
+ module_free(NULL, fp->bpf_func);
+ kfree(fp);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 12:16:07 +0000