Mode modifier is one of::
- BPF_IMM 0x00 /* used for 32-bit mov in classic BPF and 64-bit in eBPF */
- BPF_ABS 0x20
- BPF_IND 0x40
- BPF_MEM 0x60
- BPF_LEN 0x80 /* classic BPF only, reserved in eBPF */
- BPF_MSH 0xa0 /* classic BPF only, reserved in eBPF */
- BPF_XADD 0xc0 /* eBPF only, exclusive add */
+ BPF_IMM 0x00 /* used for 32-bit mov in classic BPF and 64-bit in eBPF */
+ BPF_ABS 0x20
+ BPF_IND 0x40
+ BPF_MEM 0x60
+ BPF_LEN 0x80 /* classic BPF only, reserved in eBPF */
+ BPF_MSH 0xa0 /* classic BPF only, reserved in eBPF */
+ BPF_ATOMIC 0xc0 /* eBPF only, atomic operations */
eBPF has two non-generic instructions: (BPF_ABS | <size> | BPF_LD) and
(BPF_IND | <size> | BPF_LD) which are used to access packet data.
BPF_MEM | <size> | BPF_STX: *(size *) (dst_reg + off) = src_reg
BPF_MEM | <size> | BPF_ST: *(size *) (dst_reg + off) = imm32
BPF_MEM | <size> | BPF_LDX: dst_reg = *(size *) (src_reg + off)
- BPF_XADD | BPF_W | BPF_STX: lock xadd *(u32 *)(dst_reg + off16) += src_reg
- BPF_XADD | BPF_DW | BPF_STX: lock xadd *(u64 *)(dst_reg + off16) += src_reg
-Where size is one of: BPF_B or BPF_H or BPF_W or BPF_DW. Note that 1 and
-2 byte atomic increments are not supported.
+Where size is one of: BPF_B or BPF_H or BPF_W or BPF_DW.
+
+It also includes atomic operations, which use the immediate field for extra
+encoding.
+
+ .imm = BPF_ADD, .code = BPF_ATOMIC | BPF_W | BPF_STX: lock xadd *(u32 *)(dst_reg + off16) += src_reg
+ .imm = BPF_ADD, .code = BPF_ATOMIC | BPF_DW | BPF_STX: lock xadd *(u64 *)(dst_reg + off16) += src_reg
+
+Note that 1 and 2 byte atomic operations are not supported.
+
+You may encounter BPF_XADD - this is a legacy name for BPF_ATOMIC, referring to
+the exclusive-add operation encoded when the immediate field is zero.
eBPF has one 16-byte instruction: BPF_LD | BPF_DW | BPF_IMM which consists
of two consecutive ``struct bpf_insn`` 8-byte blocks and interpreted as single
}
emit_str_r(dst_lo, tmp2, off, ctx, BPF_SIZE(code));
break;
- /* STX XADD: lock *(u32 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_W:
- /* STX XADD: lock *(u64 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_DW:
+ /* Atomic ops */
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
goto notyet;
/* STX: *(size *)(dst + off) = src */
case BPF_STX | BPF_MEM | BPF_W:
}
break;
- /* STX XADD: lock *(u32 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_W:
- /* STX XADD: lock *(u64 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_DW:
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ if (insn->imm != BPF_ADD) {
+ pr_err_once("unknown atomic op code %02x\n", insn->imm);
+ return -EINVAL;
+ }
+
+ /* STX XADD: lock *(u32 *)(dst + off) += src
+ * and
+ * STX XADD: lock *(u64 *)(dst + off) += src
+ */
+
if (!off) {
reg = dst;
} else {
case BPF_STX | BPF_H | BPF_MEM:
case BPF_STX | BPF_W | BPF_MEM:
case BPF_STX | BPF_DW | BPF_MEM:
- case BPF_STX | BPF_W | BPF_XADD:
- case BPF_STX | BPF_DW | BPF_XADD:
+ case BPF_STX | BPF_W | BPF_ATOMIC:
+ case BPF_STX | BPF_DW | BPF_ATOMIC:
if (insn->dst_reg == BPF_REG_10) {
ctx->flags |= EBPF_SEEN_FP;
dst = MIPS_R_SP;
src = ebpf_to_mips_reg(ctx, insn, src_reg_no_fp);
if (src < 0)
return src;
- if (BPF_MODE(insn->code) == BPF_XADD) {
+ if (BPF_MODE(insn->code) == BPF_ATOMIC) {
+ if (insn->imm != BPF_ADD) {
+ pr_err("ATOMIC OP %02x NOT HANDLED\n", insn->imm);
+ return -EINVAL;
+ }
+
/*
* If mem_off does not fit within the 9 bit ll/sc
* instruction immediate field, use a temp reg.
break;
/*
- * BPF_STX XADD (atomic_add)
+ * BPF_STX ATOMIC (atomic ops)
*/
- /* *(u32 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ if (insn->imm != BPF_ADD) {
+ pr_err_ratelimited(
+ "eBPF filter atomic op code %02x (@%d) unsupported\n",
+ code, i);
+ return -ENOTSUPP;
+ }
+
+ /* *(u32 *)(dst + off) += src */
+
/* Get EA into TMP_REG_1 */
EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], dst_reg, off));
tmp_idx = ctx->idx * 4;
/* we're done if this succeeded */
PPC_BCC_SHORT(COND_NE, tmp_idx);
break;
- /* *(u64 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_DW:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ if (insn->imm != BPF_ADD) {
+ pr_err_ratelimited(
+ "eBPF filter atomic op code %02x (@%d) unsupported\n",
+ code, i);
+ return -ENOTSUPP;
+ }
+ /* *(u64 *)(dst + off) += src */
+
EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], dst_reg, off));
tmp_idx = ctx->idx * 4;
EMIT(PPC_RAW_LDARX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1], 0));
const s8 *rd = bpf_get_reg64(dst, tmp1, ctx);
const s8 *rs = bpf_get_reg64(src, tmp2, ctx);
- if (mode == BPF_XADD && size != BPF_W)
+ if (mode == BPF_ATOMIC && size != BPF_W)
return -1;
emit_imm(RV_REG_T0, off, ctx);
case BPF_MEM:
emit(rv_sw(RV_REG_T0, 0, lo(rs)), ctx);
break;
- case BPF_XADD:
+ case BPF_ATOMIC: /* Only BPF_ADD supported */
emit(rv_amoadd_w(RV_REG_ZERO, lo(rs), RV_REG_T0, 0, 0),
ctx);
break;
case BPF_STX | BPF_MEM | BPF_H:
case BPF_STX | BPF_MEM | BPF_W:
case BPF_STX | BPF_MEM | BPF_DW:
- case BPF_STX | BPF_XADD | BPF_W:
if (BPF_CLASS(code) == BPF_ST) {
emit_imm32(tmp2, imm, ctx);
src = tmp2;
return -1;
break;
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ if (insn->imm != BPF_ADD) {
+ pr_info_once(
+ "bpf-jit: not supported: atomic operation %02x ***\n",
+ insn->imm);
+ return -EFAULT;
+ }
+
+ if (emit_store_r64(dst, src, off, ctx, BPF_SIZE(code),
+ BPF_MODE(code)))
+ return -1;
+ break;
+
/* No hardware support for 8-byte atomics in RV32. */
- case BPF_STX | BPF_XADD | BPF_DW:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
/* Fallthrough. */
notsupported:
emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
emit_sd(RV_REG_T1, 0, rs, ctx);
break;
- /* STX XADD: lock *(u32 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_W:
- /* STX XADD: lock *(u64 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_DW:
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ if (insn->imm != BPF_ADD) {
+ pr_err("bpf-jit: not supported: atomic operation %02x ***\n",
+ insn->imm);
+ return -EINVAL;
+ }
+
+ /* atomic_add: lock *(u32 *)(dst + off) += src
+ * atomic_add: lock *(u64 *)(dst + off) += src
+ */
+
if (off) {
if (is_12b_int(off)) {
emit_addi(RV_REG_T1, rd, off, ctx);
jit->seen |= SEEN_MEM;
break;
/*
- * BPF_STX XADD (atomic_add)
+ * BPF_ATOMIC
*/
- case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */
- /* laal %w0,%src,off(%dst) */
- EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W0, src_reg,
- dst_reg, off);
- jit->seen |= SEEN_MEM;
- break;
- case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */
- /* laalg %w0,%src,off(%dst) */
- EMIT6_DISP_LH(0xeb000000, 0x00ea, REG_W0, src_reg,
- dst_reg, off);
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ if (insn->imm != BPF_ADD) {
+ pr_err("Unknown atomic operation %02x\n", insn->imm);
+ return -1;
+ }
+
+ /* *(u32/u64 *)(dst + off) += src
+ *
+ * BFW_W: laal %w0,%src,off(%dst)
+ * BPF_DW: laalg %w0,%src,off(%dst)
+ */
+ EMIT6_DISP_LH(0xeb000000,
+ BPF_SIZE(insn->code) == BPF_W ? 0x00fa : 0x00ea,
+ REG_W0, src_reg, dst_reg, off);
jit->seen |= SEEN_MEM;
break;
/*
break;
}
- /* STX XADD: lock *(u32 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_W: {
+ case BPF_STX | BPF_ATOMIC | BPF_W: {
const u8 tmp = bpf2sparc[TMP_REG_1];
const u8 tmp2 = bpf2sparc[TMP_REG_2];
const u8 tmp3 = bpf2sparc[TMP_REG_3];
+ if (insn->imm != BPF_ADD) {
+ pr_err_once("unknown atomic op %02x\n", insn->imm);
+ return -EINVAL;
+ }
+
+ /* lock *(u32 *)(dst + off) += src */
+
if (insn->dst_reg == BPF_REG_FP)
ctx->saw_frame_pointer = true;
break;
}
/* STX XADD: lock *(u64 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_DW: {
+ case BPF_STX | BPF_ATOMIC | BPF_DW: {
const u8 tmp = bpf2sparc[TMP_REG_1];
const u8 tmp2 = bpf2sparc[TMP_REG_2];
const u8 tmp3 = bpf2sparc[TMP_REG_3];
+ if (insn->imm != BPF_ADD) {
+ pr_err_once("unknown atomic op %02x\n", insn->imm);
+ return -EINVAL;
+ }
+
if (insn->dst_reg == BPF_REG_FP)
ctx->saw_frame_pointer = true;
*pprog = prog;
}
+static int emit_atomic(u8 **pprog, u8 atomic_op,
+ u32 dst_reg, u32 src_reg, s16 off, u8 bpf_size)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+
+ EMIT1(0xF0); /* lock prefix */
+
+ maybe_emit_mod(&prog, dst_reg, src_reg, bpf_size == BPF_DW);
+
+ /* emit opcode */
+ switch (atomic_op) {
+ case BPF_ADD:
+ /* lock *(u32/u64*)(dst_reg + off) <op>= src_reg */
+ EMIT1(simple_alu_opcodes[atomic_op]);
+ break;
+ default:
+ pr_err("bpf_jit: unknown atomic opcode %02x\n", atomic_op);
+ return -EFAULT;
+ }
+
+ emit_insn_suffix(&prog, dst_reg, src_reg, off);
+
+ *pprog = prog;
+ return 0;
+}
+
static bool ex_handler_bpf(const struct exception_table_entry *x,
struct pt_regs *regs, int trapnr,
unsigned long error_code, unsigned long fault_addr)
int i, cnt = 0, excnt = 0;
int proglen = 0;
u8 *prog = temp;
+ int err;
detect_reg_usage(insn, insn_cnt, callee_regs_used,
&tail_call_seen);
}
break;
- /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */
- case BPF_STX | BPF_XADD | BPF_W:
- /* Emit 'lock add dword ptr [rax + off], eax' */
- if (is_ereg(dst_reg) || is_ereg(src_reg))
- EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01);
- else
- EMIT2(0xF0, 0x01);
- goto xadd;
- case BPF_STX | BPF_XADD | BPF_DW:
- EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01);
-xadd:
- emit_modrm_dstoff(&prog, dst_reg, src_reg, insn->off);
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ err = emit_atomic(&prog, insn->imm, dst_reg, src_reg,
+ insn->off, BPF_SIZE(insn->code));
+ if (err)
+ return err;
break;
/* call */
return -EFAULT;
}
break;
- /* STX XADD: lock *(u32 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_W:
- /* STX XADD: lock *(u64 *)(dst + off) += src */
- case BPF_STX | BPF_XADD | BPF_DW:
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
goto notyet;
case BPF_JMP | BPF_EXIT:
if (seen_exit) {
return 0;
}
-static int mem_xadd4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
+static int mem_atomic4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
+ if (meta->insn.imm != BPF_ADD)
+ return -EOPNOTSUPP;
+
return mem_xadd(nfp_prog, meta, false);
}
-static int mem_xadd8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
+static int mem_atomic8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
+ if (meta->insn.imm != BPF_ADD)
+ return -EOPNOTSUPP;
+
return mem_xadd(nfp_prog, meta, true);
}
[BPF_STX | BPF_MEM | BPF_H] = mem_stx2,
[BPF_STX | BPF_MEM | BPF_W] = mem_stx4,
[BPF_STX | BPF_MEM | BPF_DW] = mem_stx8,
- [BPF_STX | BPF_XADD | BPF_W] = mem_xadd4,
- [BPF_STX | BPF_XADD | BPF_DW] = mem_xadd8,
+ [BPF_STX | BPF_ATOMIC | BPF_W] = mem_atomic4,
+ [BPF_STX | BPF_ATOMIC | BPF_DW] = mem_atomic8,
[BPF_ST | BPF_MEM | BPF_B] = mem_st1,
[BPF_ST | BPF_MEM | BPF_H] = mem_st2,
[BPF_ST | BPF_MEM | BPF_W] = mem_st4,
return is_mbpf_classic_store(meta) && meta->ptr.type == PTR_TO_PACKET;
}
-static inline bool is_mbpf_xadd(const struct nfp_insn_meta *meta)
+static inline bool is_mbpf_atomic(const struct nfp_insn_meta *meta)
{
- return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_XADD);
+ return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_ATOMIC);
}
static inline bool is_mbpf_mul(const struct nfp_insn_meta *meta)
pr_vlog(env, "map writes not supported\n");
return -EOPNOTSUPP;
}
- if (is_mbpf_xadd(meta)) {
+ if (is_mbpf_atomic(meta)) {
err = nfp_bpf_map_mark_used(env, meta, reg,
NFP_MAP_USE_ATOMIC_CNT);
if (err)
}
static int
-nfp_bpf_check_xadd(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
- struct bpf_verifier_env *env)
+nfp_bpf_check_atomic(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
+ struct bpf_verifier_env *env)
{
const struct bpf_reg_state *sreg = cur_regs(env) + meta->insn.src_reg;
const struct bpf_reg_state *dreg = cur_regs(env) + meta->insn.dst_reg;
+ if (meta->insn.imm != BPF_ADD) {
+ pr_vlog(env, "atomic op not implemented: %d\n", meta->insn.imm);
+ return -EOPNOTSUPP;
+ }
+
if (dreg->type != PTR_TO_MAP_VALUE) {
pr_vlog(env, "atomic add not to a map value pointer: %d\n",
dreg->type);
if (is_mbpf_store(meta))
return nfp_bpf_check_store(nfp_prog, meta, env);
- if (is_mbpf_xadd(meta))
- return nfp_bpf_check_xadd(nfp_prog, meta, env);
+ if (is_mbpf_atomic(meta))
+ return nfp_bpf_check_atomic(nfp_prog, meta, env);
if (is_mbpf_alu(meta))
return nfp_bpf_check_alu(nfp_prog, meta, env);
.off = OFF, \
.imm = 0 })
-/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
-#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \
+/*
+ * Atomic operations:
+ *
+ * BPF_ADD *(uint *) (dst_reg + off16) += src_reg
+ */
+
+#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \
((struct bpf_insn) { \
- .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \
+ .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
.dst_reg = DST, \
.src_reg = SRC, \
.off = OFF, \
- .imm = 0 })
+ .imm = OP })
+
+/* Legacy alias */
+#define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
/* Memory store, *(uint *) (dst_reg + off16) = imm32 */
/* ld/ldx fields */
#define BPF_DW 0x18 /* double word (64-bit) */
-#define BPF_XADD 0xc0 /* exclusive add */
+#define BPF_ATOMIC 0xc0 /* atomic memory ops - op type in immediate */
+#define BPF_XADD 0xc0 /* exclusive add - legacy name */
/* alu/jmp fields */
#define BPF_MOV 0xb0 /* mov reg to reg */
* running simultaneously.
*
* A user should care about the synchronization by himself.
- * For example, by using the **BPF_STX_XADD** instruction to alter
+ * For example, by using the **BPF_ATOMIC** instructions to alter
* the shared data.
* Return
* A pointer to the local storage area.
INSN_3(STX, MEM, H), \
INSN_3(STX, MEM, W), \
INSN_3(STX, MEM, DW), \
- INSN_3(STX, XADD, W), \
- INSN_3(STX, XADD, DW), \
+ INSN_3(STX, ATOMIC, W), \
+ INSN_3(STX, ATOMIC, DW), \
/* Immediate based. */ \
INSN_3(ST, MEM, B), \
INSN_3(ST, MEM, H), \
LDX_PROBE(DW, 8)
#undef LDX_PROBE
- STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
- atomic_add((u32) SRC, (atomic_t *)(unsigned long)
- (DST + insn->off));
+ STX_ATOMIC_W:
+ switch (IMM) {
+ case BPF_ADD:
+ /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
+ atomic_add((u32) SRC, (atomic_t *)(unsigned long)
+ (DST + insn->off));
+ default:
+ goto default_label;
+ }
CONT;
- STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
- atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
- (DST + insn->off));
+ STX_ATOMIC_DW:
+ switch (IMM) {
+ case BPF_ADD:
+ /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
+ atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
+ (DST + insn->off));
+ default:
+ goto default_label;
+ }
CONT;
default_label:
*
* Note, verifier whitelists all opcodes in bpf_opcode_in_insntable().
*/
- pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code);
+ pr_warn("BPF interpreter: unknown opcode %02x (imm: 0x%x)\n",
+ insn->code, insn->imm);
BUG_ON(1);
return 0;
}
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
insn->dst_reg,
insn->off, insn->src_reg);
- else if (BPF_MODE(insn->code) == BPF_XADD)
+ else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+ insn->imm == BPF_ADD) {
verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
insn->code,
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
insn->dst_reg, insn->off,
insn->src_reg);
- else
+ } else {
verbose(cbs->private_data, "BUG_%02x\n", insn->code);
+ }
} else if (class == BPF_ST) {
if (BPF_MODE(insn->code) != BPF_MEM) {
verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
return err;
}
-static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn)
+static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn)
{
int err;
- if ((BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) ||
- insn->imm != 0) {
- verbose(env, "BPF_XADD uses reserved fields\n");
+ if (insn->imm != BPF_ADD) {
+ verbose(env, "BPF_ATOMIC uses invalid atomic opcode %02x\n", insn->imm);
+ return -EINVAL;
+ }
+
+ if (BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) {
+ verbose(env, "invalid atomic operand size\n");
return -EINVAL;
}
is_pkt_reg(env, insn->dst_reg) ||
is_flow_key_reg(env, insn->dst_reg) ||
is_sk_reg(env, insn->dst_reg)) {
- verbose(env, "BPF_XADD stores into R%d %s is not allowed\n",
+ verbose(env, "BPF_ATOMIC stores into R%d %s is not allowed\n",
insn->dst_reg,
reg_type_str[reg_state(env, insn->dst_reg)->type]);
return -EACCES;
}
- /* check whether atomic_add can read the memory */
+ /* check whether we can read the memory */
err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
BPF_SIZE(insn->code), BPF_READ, -1, true);
if (err)
return err;
- /* check whether atomic_add can write into the same memory */
+ /* check whether we can write into the same memory */
return check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
BPF_SIZE(insn->code), BPF_WRITE, -1, true);
}
} else if (class == BPF_STX) {
enum bpf_reg_type *prev_dst_type, dst_reg_type;
- if (BPF_MODE(insn->code) == BPF_XADD) {
- err = check_xadd(env, env->insn_idx, insn);
+ if (BPF_MODE(insn->code) == BPF_ATOMIC) {
+ err = check_atomic(env, env->insn_idx, insn);
if (err)
return err;
env->insn_idx++;
if (BPF_CLASS(insn->code) == BPF_STX &&
((BPF_MODE(insn->code) != BPF_MEM &&
- BPF_MODE(insn->code) != BPF_XADD) || insn->imm != 0)) {
+ BPF_MODE(insn->code) != BPF_ATOMIC) || insn->imm != 0)) {
verbose(env, "BPF_STX uses reserved fields\n");
return -EINVAL;
}
{ { 0, 0xffffffff } },
.stack_depth = 40,
},
- /* BPF_STX | BPF_XADD | BPF_W/DW */
+ /* BPF_STX | BPF_ATOMIC | BPF_W/DW */
{
"STX_XADD_W: Test: 0x12 + 0x10 = 0x22",
.u.insns_int = {
BPF_ALU32_IMM(BPF_MOV, R0, 0x12),
BPF_ST_MEM(BPF_W, R10, -40, 0x10),
- BPF_STX_XADD(BPF_W, R10, R0, -40),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, R10, R0, -40),
BPF_LDX_MEM(BPF_W, R0, R10, -40),
BPF_EXIT_INSN(),
},
BPF_ALU64_REG(BPF_MOV, R1, R10),
BPF_ALU32_IMM(BPF_MOV, R0, 0x12),
BPF_ST_MEM(BPF_W, R10, -40, 0x10),
- BPF_STX_XADD(BPF_W, R10, R0, -40),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, R10, R0, -40),
BPF_ALU64_REG(BPF_MOV, R0, R10),
BPF_ALU64_REG(BPF_SUB, R0, R1),
BPF_EXIT_INSN(),
.u.insns_int = {
BPF_ALU32_IMM(BPF_MOV, R0, 0x12),
BPF_ST_MEM(BPF_W, R10, -40, 0x10),
- BPF_STX_XADD(BPF_W, R10, R0, -40),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, R10, R0, -40),
BPF_EXIT_INSN(),
},
INTERNAL,
.u.insns_int = {
BPF_ALU32_IMM(BPF_MOV, R0, 0x12),
BPF_ST_MEM(BPF_DW, R10, -40, 0x10),
- BPF_STX_XADD(BPF_DW, R10, R0, -40),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, R10, R0, -40),
BPF_LDX_MEM(BPF_DW, R0, R10, -40),
BPF_EXIT_INSN(),
},
BPF_ALU64_REG(BPF_MOV, R1, R10),
BPF_ALU32_IMM(BPF_MOV, R0, 0x12),
BPF_ST_MEM(BPF_DW, R10, -40, 0x10),
- BPF_STX_XADD(BPF_DW, R10, R0, -40),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, R10, R0, -40),
BPF_ALU64_REG(BPF_MOV, R0, R10),
BPF_ALU64_REG(BPF_SUB, R0, R1),
BPF_EXIT_INSN(),
.u.insns_int = {
BPF_ALU32_IMM(BPF_MOV, R0, 0x12),
BPF_ST_MEM(BPF_DW, R10, -40, 0x10),
- BPF_STX_XADD(BPF_DW, R10, R0, -40),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, R10, R0, -40),
BPF_EXIT_INSN(),
},
INTERNAL,
#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \
((struct bpf_insn) { \
- .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \
+ .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
.dst_reg = DST, \
.src_reg = SRC, \
.off = OFF, \
- .imm = 0 })
+ .imm = BPF_ADD })
/* Memory store, *(uint *) (dst_reg + off16) = imm32 */
*/
BPF_MOV64_REG(BPF_REG_9, BPF_REG_0),
BPF_MOV64_IMM(BPF_REG_1, 1),
- BPF_STX_XADD(BPF_DW, BPF_REG_9, BPF_REG_1,
- offsetof(struct stats, packets)),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_9, BPF_REG_1,
+ offsetof(struct stats, packets)),
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_6,
offsetof(struct __sk_buff, len)),
- BPF_STX_XADD(BPF_DW, BPF_REG_9, BPF_REG_1,
- offsetof(struct stats, bytes)),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_9, BPF_REG_1,
+ offsetof(struct stats, bytes)),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6,
offsetof(struct __sk_buff, len)),
BPF_EXIT_INSN(),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_MOV64_IMM(BPF_REG_1, 1), /* r1 = 1 */
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* xadd r0 += r1 */
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
BPF_MOV64_IMM(BPF_REG_0, 0), /* r0 = 0 */
BPF_EXIT_INSN(),
};
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_MOV64_IMM(BPF_REG_1, 1), /* r1 = 1 */
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* xadd r0 += r1 */
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
/* Count bytes */
BPF_MOV64_IMM(BPF_REG_0, MAP_KEY_BYTES), /* r0 = 1 */
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_6, offsetof(struct __sk_buff, len)), /* r1 = skb->len */
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* xadd r0 += r1 */
+
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */
BPF_EXIT_INSN(),
.off = OFF, \
.imm = 0 })
-/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
+/*
+ * Atomic operations:
+ *
+ * BPF_ADD *(uint *) (dst_reg + off16) += src_reg
+ */
-#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \
+#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \
((struct bpf_insn) { \
- .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \
+ .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
.dst_reg = DST, \
.src_reg = SRC, \
.off = OFF, \
- .imm = 0 })
+ .imm = OP })
+
+/* Legacy alias */
+#define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
/* Memory store, *(uint *) (dst_reg + off16) = imm32 */
/* ld/ldx fields */
#define BPF_DW 0x18 /* double word (64-bit) */
-#define BPF_XADD 0xc0 /* exclusive add */
+#define BPF_ATOMIC 0xc0 /* atomic memory ops - op type in immediate */
+#define BPF_XADD 0xc0 /* exclusive add - legacy name */
/* alu/jmp fields */
#define BPF_MOV 0xb0 /* mov reg to reg */
* running simultaneously.
*
* A user should care about the synchronization by himself.
- * For example, by using the **BPF_STX_XADD** instruction to alter
+ * For example, by using the **BPF_ATOMIC** instructions to alter
* the shared data.
* Return
* A pointer to the local storage area.
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_MOV64_IMM(BPF_REG_1, val), /* r1 = 1 */
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* xadd r0 += r1 */
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
BPF_LD_MAP_FD(BPF_REG_1, cgroup_storage_fd),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage),
BPF_MOV64_IMM(BPF_REG_1, val),
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_W, BPF_REG_0, BPF_REG_1, 0, 0),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
BPF_LD_MAP_FD(BPF_REG_1, percpu_cgroup_storage_fd),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_local_storage),
BPF_MOV64_IMM(BPF_REG_1, 1),
- BPF_STX_XADD(BPF_DW, BPF_REG_0, BPF_REG_1, 0),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x1),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "context stores via XADD",
+ "context stores via BPF_ATOMIC",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_W, BPF_REG_1,
- BPF_REG_0, offsetof(struct __sk_buff, mark), 0),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_1, BPF_REG_0, offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
- .errstr = "BPF_XADD stores into R1 ctx is not allowed",
+ .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_2, 0),
- BPF_STX_XADD(BPF_DW, BPF_REG_4, BPF_REG_5, 0),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_4, BPF_REG_5, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_4, 0),
BPF_STX_MEM(BPF_W, BPF_REG_2, BPF_REG_5, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 11),
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -8),
BPF_MOV64_IMM(BPF_REG_4, 0xffffffff),
- BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_4, -8),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_10, BPF_REG_4, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -8),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 49),
BPF_ALU64_REG(BPF_ADD, BPF_REG_4, BPF_REG_2),
BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
offsetof(struct __sk_buff, cb[0])),
BPF_LD_MAP_FD(BPF_REG_2, 0),
- BPF_STX_XADD(BPF_DW, BPF_REG_1, BPF_REG_2,
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_1, BPF_REG_2,
offsetof(struct __sk_buff, cb[0])),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "R2 leaks addr into mem",
.result_unpriv = REJECT,
.result = REJECT,
- .errstr = "BPF_XADD stores into R1 ctx is not allowed",
+ .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed",
},
{
"leak pointer into ctx 2",
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
offsetof(struct __sk_buff, cb[0])),
- BPF_STX_XADD(BPF_DW, BPF_REG_1, BPF_REG_10,
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_1, BPF_REG_10,
offsetof(struct __sk_buff, cb[0])),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "R10 leaks addr into mem",
.result_unpriv = REJECT,
.result = REJECT,
- .errstr = "BPF_XADD stores into R1 ctx is not allowed",
+ .errstr = "BPF_ATOMIC stores into R1 ctx is not allowed",
},
{
"leak pointer into ctx 3",
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3),
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_3, 0),
- BPF_STX_XADD(BPF_DW, BPF_REG_0, BPF_REG_6, 0),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_6, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
BPF_MOV64_IMM(BPF_REG_5, 42),
BPF_MOV64_IMM(BPF_REG_6, 24),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_5, -8),
- BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_10, BPF_REG_6, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -8),
BPF_JMP_IMM(BPF_JGT, BPF_REG_5, 100, 6),
BPF_ALU64_REG(BPF_ADD, BPF_REG_3, BPF_REG_5),
BPF_MOV64_IMM(BPF_REG_5, 42),
BPF_MOV64_IMM(BPF_REG_6, 24),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_5, -8),
- BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_10, BPF_REG_6, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -8),
BPF_JMP_IMM(BPF_JGT, BPF_REG_5, 100, 6),
BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_5),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, -8),
BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_10, BPF_REG_0, -8, 0),
+ BPF_RAW_INSN(BPF_STX | BPF_ATOMIC | BPF_DW,
+ BPF_REG_10, BPF_REG_0, -8, BPF_ADD),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_hash_recalc),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_0, 0),
- BPF_STX_XADD(BPF_DW, BPF_REG_2, BPF_REG_3, 0),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_2, BPF_REG_3, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 22),
BPF_EXIT_INSN(),
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
- BPF_STX_XADD(BPF_W, BPF_REG_10, BPF_REG_0, -7),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_10, BPF_REG_0, -7),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_EXIT_INSN(),
},
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_1, 1),
- BPF_STX_XADD(BPF_W, BPF_REG_0, BPF_REG_1, 3),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_0, BPF_REG_1, 3),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 3),
BPF_EXIT_INSN(),
},
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_ST_MEM(BPF_W, BPF_REG_2, 0, 0),
BPF_ST_MEM(BPF_W, BPF_REG_2, 3, 0),
- BPF_STX_XADD(BPF_W, BPF_REG_2, BPF_REG_0, 1),
- BPF_STX_XADD(BPF_W, BPF_REG_2, BPF_REG_0, 2),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_2, BPF_REG_0, 1),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_2, BPF_REG_0, 2),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_2, 1),
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "BPF_XADD stores into R2 pkt is not allowed",
+ .errstr = "BPF_ATOMIC stores into R2 pkt is not allowed",
.prog_type = BPF_PROG_TYPE_XDP,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
- BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
- BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_10, BPF_REG_0, -8),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_10, BPF_REG_0, -8),
BPF_JMP_REG(BPF_JNE, BPF_REG_6, BPF_REG_0, 3),
BPF_JMP_REG(BPF_JNE, BPF_REG_7, BPF_REG_10, 2),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -8),
- BPF_STX_XADD(BPF_W, BPF_REG_10, BPF_REG_0, -8),
- BPF_STX_XADD(BPF_W, BPF_REG_10, BPF_REG_0, -8),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_10, BPF_REG_0, -8),
+ BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_10, BPF_REG_0, -8),
BPF_JMP_REG(BPF_JNE, BPF_REG_6, BPF_REG_0, 3),
BPF_JMP_REG(BPF_JNE, BPF_REG_7, BPF_REG_10, 2),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -8),
projects / users / hch / configfs.git / commitdiff