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-rw-r--r--kernel/bpf/core.c96
1 files changed, 8 insertions, 88 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 90feeba3a1a1..1127552c8033 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -634,23 +634,6 @@ static int bpf_jit_blind_insn(const struct bpf_insn *from,
*to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off);
break;
- case BPF_LD | BPF_ABS | BPF_W:
- case BPF_LD | BPF_ABS | BPF_H:
- case BPF_LD | BPF_ABS | BPF_B:
- *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
- *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
- *to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0);
- break;
-
- case BPF_LD | BPF_IND | BPF_W:
- case BPF_LD | BPF_IND | BPF_H:
- case BPF_LD | BPF_IND | BPF_B:
- *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
- *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
- *to++ = BPF_ALU32_REG(BPF_ADD, BPF_REG_AX, from->src_reg);
- *to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0);
- break;
-
case BPF_LD | BPF_IMM | BPF_DW:
*to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm);
*to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
@@ -891,14 +874,7 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
INSN_3(LDX, MEM, W), \
INSN_3(LDX, MEM, DW), \
/* Immediate based. */ \
- INSN_3(LD, IMM, DW), \
- /* Misc (old cBPF carry-over). */ \
- INSN_3(LD, ABS, B), \
- INSN_3(LD, ABS, H), \
- INSN_3(LD, ABS, W), \
- INSN_3(LD, IND, B), \
- INSN_3(LD, IND, H), \
- INSN_3(LD, IND, W)
+ INSN_3(LD, IMM, DW)
bool bpf_opcode_in_insntable(u8 code)
{
@@ -908,6 +884,13 @@ bool bpf_opcode_in_insntable(u8 code)
[0 ... 255] = false,
/* Now overwrite non-defaults ... */
BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL),
+ /* UAPI exposed, but rewritten opcodes. cBPF carry-over. */
+ [BPF_LD | BPF_ABS | BPF_B] = true,
+ [BPF_LD | BPF_ABS | BPF_H] = true,
+ [BPF_LD | BPF_ABS | BPF_W] = true,
+ [BPF_LD | BPF_IND | BPF_B] = true,
+ [BPF_LD | BPF_IND | BPF_H] = true,
+ [BPF_LD | BPF_IND | BPF_W] = true,
};
#undef BPF_INSN_3_TBL
#undef BPF_INSN_2_TBL
@@ -938,8 +921,6 @@ static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
#undef BPF_INSN_3_LBL
#undef BPF_INSN_2_LBL
u32 tail_call_cnt = 0;
- void *ptr;
- int off;
#define CONT ({ insn++; goto select_insn; })
#define CONT_JMP ({ insn++; goto select_insn; })
@@ -1266,67 +1247,6 @@ out:
atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
(DST + insn->off));
CONT;
- LD_ABS_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + imm32)) */
- off = IMM;
-load_word:
- /* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are only
- * appearing in the programs where ctx == skb
- * (see may_access_skb() in the verifier). All programs
- * keep 'ctx' in regs[BPF_REG_CTX] == BPF_R6,
- * bpf_convert_filter() saves it in BPF_R6, internal BPF
- * verifier will check that BPF_R6 == ctx.
- *
- * BPF_ABS and BPF_IND are wrappers of function calls,
- * so they scratch BPF_R1-BPF_R5 registers, preserve
- * BPF_R6-BPF_R9, and store return value into BPF_R0.
- *
- * Implicit input:
- * ctx == skb == BPF_R6 == CTX
- *
- * Explicit input:
- * SRC == any register
- * IMM == 32-bit immediate
- *
- * Output:
- * BPF_R0 - 8/16/32-bit skb data converted to cpu endianness
- */
-
- ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 4, &tmp);
- if (likely(ptr != NULL)) {
- BPF_R0 = get_unaligned_be32(ptr);
- CONT;
- }
-
- return 0;
- LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + imm32)) */
- off = IMM;
-load_half:
- ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp);
- if (likely(ptr != NULL)) {
- BPF_R0 = get_unaligned_be16(ptr);
- CONT;
- }
-
- return 0;
- LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */
- off = IMM;
-load_byte:
- ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp);
- if (likely(ptr != NULL)) {
- BPF_R0 = *(u8 *)ptr;
- CONT;
- }
-
- return 0;
- LD_IND_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + src_reg + imm32)) */
- off = IMM + SRC;
- goto load_word;
- LD_IND_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + src_reg + imm32)) */
- off = IMM + SRC;
- goto load_half;
- LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + src_reg + imm32) */
- off = IMM + SRC;
- goto load_byte;
default_label:
/* If we ever reach this, we have a bug somewhere. Die hard here