2 * Linux Socket Filter - Kernel level socket filtering
4 * Based on the design of the Berkeley Packet Filter. The new
5 * internal format has been designed by PLUMgrid:
7 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
11 * Jay Schulist <jschlst@samba.org>
12 * Alexei Starovoitov <ast@plumgrid.com>
13 * Daniel Borkmann <dborkman@redhat.com>
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
20 * Andi Kleen - Fix a few bad bugs and races.
21 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
24 #include <linux/module.h>
25 #include <linux/types.h>
27 #include <linux/fcntl.h>
28 #include <linux/socket.h>
30 #include <linux/inet.h>
31 #include <linux/netdevice.h>
32 #include <linux/if_packet.h>
33 #include <linux/gfp.h>
35 #include <net/protocol.h>
36 #include <net/netlink.h>
37 #include <linux/skbuff.h>
39 #include <net/flow_dissector.h>
40 #include <linux/errno.h>
41 #include <linux/timer.h>
42 #include <asm/uaccess.h>
43 #include <asm/unaligned.h>
44 #include <linux/filter.h>
45 #include <linux/ratelimit.h>
46 #include <linux/seccomp.h>
47 #include <linux/if_vlan.h>
48 #include <linux/bpf.h>
49 #include <net/sch_generic.h>
50 #include <net/cls_cgroup.h>
51 #include <net/dst_metadata.h>
53 #include <net/sock_reuseport.h>
56 * sk_filter_trim_cap - run a packet through a socket filter
57 * @sk: sock associated with &sk_buff
58 * @skb: buffer to filter
59 * @cap: limit on how short the eBPF program may trim the packet
61 * Run the eBPF program and then cut skb->data to correct size returned by
62 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
63 * than pkt_len we keep whole skb->data. This is the socket level
64 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
65 * be accepted or -EPERM if the packet should be tossed.
68 int sk_filter_trim_cap(struct sock
*sk
, struct sk_buff
*skb
, unsigned int cap
)
71 struct sk_filter
*filter
;
74 * If the skb was allocated from pfmemalloc reserves, only
75 * allow SOCK_MEMALLOC sockets to use it as this socket is
78 if (skb_pfmemalloc(skb
) && !sock_flag(sk
, SOCK_MEMALLOC
))
81 err
= security_sock_rcv_skb(sk
, skb
);
86 filter
= rcu_dereference(sk
->sk_filter
);
88 unsigned int pkt_len
= bpf_prog_run_save_cb(filter
->prog
, skb
);
89 err
= pkt_len
? pskb_trim(skb
, max(cap
, pkt_len
)) : -EPERM
;
95 EXPORT_SYMBOL(sk_filter_trim_cap
);
97 static u64
__skb_get_pay_offset(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
99 return skb_get_poff((struct sk_buff
*)(unsigned long) ctx
);
102 static u64
__skb_get_nlattr(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
104 struct sk_buff
*skb
= (struct sk_buff
*)(unsigned long) ctx
;
107 if (skb_is_nonlinear(skb
))
110 if (skb
->len
< sizeof(struct nlattr
))
113 if (a
> skb
->len
- sizeof(struct nlattr
))
116 nla
= nla_find((struct nlattr
*) &skb
->data
[a
], skb
->len
- a
, x
);
118 return (void *) nla
- (void *) skb
->data
;
123 static u64
__skb_get_nlattr_nest(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
125 struct sk_buff
*skb
= (struct sk_buff
*)(unsigned long) ctx
;
128 if (skb_is_nonlinear(skb
))
131 if (skb
->len
< sizeof(struct nlattr
))
134 if (a
> skb
->len
- sizeof(struct nlattr
))
137 nla
= (struct nlattr
*) &skb
->data
[a
];
138 if (nla
->nla_len
> skb
->len
- a
)
141 nla
= nla_find_nested(nla
, x
);
143 return (void *) nla
- (void *) skb
->data
;
148 static u64
__get_raw_cpu_id(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
150 return raw_smp_processor_id();
153 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto
= {
154 .func
= __get_raw_cpu_id
,
156 .ret_type
= RET_INTEGER
,
159 static u32
convert_skb_access(int skb_field
, int dst_reg
, int src_reg
,
160 struct bpf_insn
*insn_buf
)
162 struct bpf_insn
*insn
= insn_buf
;
166 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
168 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
169 offsetof(struct sk_buff
, mark
));
173 *insn
++ = BPF_LDX_MEM(BPF_B
, dst_reg
, src_reg
, PKT_TYPE_OFFSET());
174 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, PKT_TYPE_MAX
);
175 #ifdef __BIG_ENDIAN_BITFIELD
176 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 5);
181 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, queue_mapping
) != 2);
183 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
184 offsetof(struct sk_buff
, queue_mapping
));
187 case SKF_AD_VLAN_TAG
:
188 case SKF_AD_VLAN_TAG_PRESENT
:
189 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_tci
) != 2);
190 BUILD_BUG_ON(VLAN_TAG_PRESENT
!= 0x1000);
192 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
193 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
194 offsetof(struct sk_buff
, vlan_tci
));
195 if (skb_field
== SKF_AD_VLAN_TAG
) {
196 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
,
200 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 12);
202 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, 1);
207 return insn
- insn_buf
;
210 static bool convert_bpf_extensions(struct sock_filter
*fp
,
211 struct bpf_insn
**insnp
)
213 struct bpf_insn
*insn
= *insnp
;
217 case SKF_AD_OFF
+ SKF_AD_PROTOCOL
:
218 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
220 /* A = *(u16 *) (CTX + offsetof(protocol)) */
221 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
222 offsetof(struct sk_buff
, protocol
));
223 /* A = ntohs(A) [emitting a nop or swap16] */
224 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
227 case SKF_AD_OFF
+ SKF_AD_PKTTYPE
:
228 cnt
= convert_skb_access(SKF_AD_PKTTYPE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
232 case SKF_AD_OFF
+ SKF_AD_IFINDEX
:
233 case SKF_AD_OFF
+ SKF_AD_HATYPE
:
234 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
235 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, type
) != 2);
236 BUILD_BUG_ON(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)) < 0);
238 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
239 BPF_REG_TMP
, BPF_REG_CTX
,
240 offsetof(struct sk_buff
, dev
));
241 /* if (tmp != 0) goto pc + 1 */
242 *insn
++ = BPF_JMP_IMM(BPF_JNE
, BPF_REG_TMP
, 0, 1);
243 *insn
++ = BPF_EXIT_INSN();
244 if (fp
->k
== SKF_AD_OFF
+ SKF_AD_IFINDEX
)
245 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_TMP
,
246 offsetof(struct net_device
, ifindex
));
248 *insn
= BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_TMP
,
249 offsetof(struct net_device
, type
));
252 case SKF_AD_OFF
+ SKF_AD_MARK
:
253 cnt
= convert_skb_access(SKF_AD_MARK
, BPF_REG_A
, BPF_REG_CTX
, insn
);
257 case SKF_AD_OFF
+ SKF_AD_RXHASH
:
258 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
260 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
,
261 offsetof(struct sk_buff
, hash
));
264 case SKF_AD_OFF
+ SKF_AD_QUEUE
:
265 cnt
= convert_skb_access(SKF_AD_QUEUE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
269 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG
:
270 cnt
= convert_skb_access(SKF_AD_VLAN_TAG
,
271 BPF_REG_A
, BPF_REG_CTX
, insn
);
275 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
:
276 cnt
= convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
277 BPF_REG_A
, BPF_REG_CTX
, insn
);
281 case SKF_AD_OFF
+ SKF_AD_VLAN_TPID
:
282 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
284 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
285 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
286 offsetof(struct sk_buff
, vlan_proto
));
287 /* A = ntohs(A) [emitting a nop or swap16] */
288 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
291 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
292 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
293 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
294 case SKF_AD_OFF
+ SKF_AD_CPU
:
295 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
297 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG1
, BPF_REG_CTX
);
299 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG2
, BPF_REG_A
);
301 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG3
, BPF_REG_X
);
302 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
304 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
305 *insn
= BPF_EMIT_CALL(__skb_get_pay_offset
);
307 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
308 *insn
= BPF_EMIT_CALL(__skb_get_nlattr
);
310 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
311 *insn
= BPF_EMIT_CALL(__skb_get_nlattr_nest
);
313 case SKF_AD_OFF
+ SKF_AD_CPU
:
314 *insn
= BPF_EMIT_CALL(__get_raw_cpu_id
);
316 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
317 *insn
= BPF_EMIT_CALL(bpf_user_rnd_u32
);
318 bpf_user_rnd_init_once();
323 case SKF_AD_OFF
+ SKF_AD_ALU_XOR_X
:
325 *insn
= BPF_ALU32_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_X
);
329 /* This is just a dummy call to avoid letting the compiler
330 * evict __bpf_call_base() as an optimization. Placed here
331 * where no-one bothers.
333 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
342 * bpf_convert_filter - convert filter program
343 * @prog: the user passed filter program
344 * @len: the length of the user passed filter program
345 * @new_prog: buffer where converted program will be stored
346 * @new_len: pointer to store length of converted program
348 * Remap 'sock_filter' style BPF instruction set to 'sock_filter_ext' style.
349 * Conversion workflow:
351 * 1) First pass for calculating the new program length:
352 * bpf_convert_filter(old_prog, old_len, NULL, &new_len)
354 * 2) 2nd pass to remap in two passes: 1st pass finds new
355 * jump offsets, 2nd pass remapping:
356 * new_prog = kmalloc(sizeof(struct bpf_insn) * new_len);
357 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
359 static int bpf_convert_filter(struct sock_filter
*prog
, int len
,
360 struct bpf_insn
*new_prog
, int *new_len
)
362 int new_flen
= 0, pass
= 0, target
, i
;
363 struct bpf_insn
*new_insn
;
364 struct sock_filter
*fp
;
368 BUILD_BUG_ON(BPF_MEMWORDS
* sizeof(u32
) > MAX_BPF_STACK
);
369 BUILD_BUG_ON(BPF_REG_FP
+ 1 != MAX_BPF_REG
);
371 if (len
<= 0 || len
> BPF_MAXINSNS
)
375 addrs
= kcalloc(len
, sizeof(*addrs
),
376 GFP_KERNEL
| __GFP_NOWARN
);
385 /* Classic BPF related prologue emission. */
387 /* Classic BPF expects A and X to be reset first. These need
388 * to be guaranteed to be the first two instructions.
390 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_A
);
391 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_X
, BPF_REG_X
);
393 /* All programs must keep CTX in callee saved BPF_REG_CTX.
394 * In eBPF case it's done by the compiler, here we need to
395 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
397 *new_insn
++ = BPF_MOV64_REG(BPF_REG_CTX
, BPF_REG_ARG1
);
402 for (i
= 0; i
< len
; fp
++, i
++) {
403 struct bpf_insn tmp_insns
[6] = { };
404 struct bpf_insn
*insn
= tmp_insns
;
407 addrs
[i
] = new_insn
- new_prog
;
410 /* All arithmetic insns and skb loads map as-is. */
411 case BPF_ALU
| BPF_ADD
| BPF_X
:
412 case BPF_ALU
| BPF_ADD
| BPF_K
:
413 case BPF_ALU
| BPF_SUB
| BPF_X
:
414 case BPF_ALU
| BPF_SUB
| BPF_K
:
415 case BPF_ALU
| BPF_AND
| BPF_X
:
416 case BPF_ALU
| BPF_AND
| BPF_K
:
417 case BPF_ALU
| BPF_OR
| BPF_X
:
418 case BPF_ALU
| BPF_OR
| BPF_K
:
419 case BPF_ALU
| BPF_LSH
| BPF_X
:
420 case BPF_ALU
| BPF_LSH
| BPF_K
:
421 case BPF_ALU
| BPF_RSH
| BPF_X
:
422 case BPF_ALU
| BPF_RSH
| BPF_K
:
423 case BPF_ALU
| BPF_XOR
| BPF_X
:
424 case BPF_ALU
| BPF_XOR
| BPF_K
:
425 case BPF_ALU
| BPF_MUL
| BPF_X
:
426 case BPF_ALU
| BPF_MUL
| BPF_K
:
427 case BPF_ALU
| BPF_DIV
| BPF_X
:
428 case BPF_ALU
| BPF_DIV
| BPF_K
:
429 case BPF_ALU
| BPF_MOD
| BPF_X
:
430 case BPF_ALU
| BPF_MOD
| BPF_K
:
431 case BPF_ALU
| BPF_NEG
:
432 case BPF_LD
| BPF_ABS
| BPF_W
:
433 case BPF_LD
| BPF_ABS
| BPF_H
:
434 case BPF_LD
| BPF_ABS
| BPF_B
:
435 case BPF_LD
| BPF_IND
| BPF_W
:
436 case BPF_LD
| BPF_IND
| BPF_H
:
437 case BPF_LD
| BPF_IND
| BPF_B
:
438 /* Check for overloaded BPF extension and
439 * directly convert it if found, otherwise
440 * just move on with mapping.
442 if (BPF_CLASS(fp
->code
) == BPF_LD
&&
443 BPF_MODE(fp
->code
) == BPF_ABS
&&
444 convert_bpf_extensions(fp
, &insn
))
447 *insn
= BPF_RAW_INSN(fp
->code
, BPF_REG_A
, BPF_REG_X
, 0, fp
->k
);
450 /* Jump transformation cannot use BPF block macros
451 * everywhere as offset calculation and target updates
452 * require a bit more work than the rest, i.e. jump
453 * opcodes map as-is, but offsets need adjustment.
456 #define BPF_EMIT_JMP \
458 if (target >= len || target < 0) \
460 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
461 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
462 insn->off -= insn - tmp_insns; \
465 case BPF_JMP
| BPF_JA
:
466 target
= i
+ fp
->k
+ 1;
467 insn
->code
= fp
->code
;
471 case BPF_JMP
| BPF_JEQ
| BPF_K
:
472 case BPF_JMP
| BPF_JEQ
| BPF_X
:
473 case BPF_JMP
| BPF_JSET
| BPF_K
:
474 case BPF_JMP
| BPF_JSET
| BPF_X
:
475 case BPF_JMP
| BPF_JGT
| BPF_K
:
476 case BPF_JMP
| BPF_JGT
| BPF_X
:
477 case BPF_JMP
| BPF_JGE
| BPF_K
:
478 case BPF_JMP
| BPF_JGE
| BPF_X
:
479 if (BPF_SRC(fp
->code
) == BPF_K
&& (int) fp
->k
< 0) {
480 /* BPF immediates are signed, zero extend
481 * immediate into tmp register and use it
484 *insn
++ = BPF_MOV32_IMM(BPF_REG_TMP
, fp
->k
);
486 insn
->dst_reg
= BPF_REG_A
;
487 insn
->src_reg
= BPF_REG_TMP
;
490 insn
->dst_reg
= BPF_REG_A
;
492 bpf_src
= BPF_SRC(fp
->code
);
493 insn
->src_reg
= bpf_src
== BPF_X
? BPF_REG_X
: 0;
496 /* Common case where 'jump_false' is next insn. */
498 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
499 target
= i
+ fp
->jt
+ 1;
504 /* Convert JEQ into JNE when 'jump_true' is next insn. */
505 if (fp
->jt
== 0 && BPF_OP(fp
->code
) == BPF_JEQ
) {
506 insn
->code
= BPF_JMP
| BPF_JNE
| bpf_src
;
507 target
= i
+ fp
->jf
+ 1;
512 /* Other jumps are mapped into two insns: Jxx and JA. */
513 target
= i
+ fp
->jt
+ 1;
514 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
518 insn
->code
= BPF_JMP
| BPF_JA
;
519 target
= i
+ fp
->jf
+ 1;
523 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
524 case BPF_LDX
| BPF_MSH
| BPF_B
:
526 *insn
++ = BPF_MOV64_REG(BPF_REG_TMP
, BPF_REG_A
);
527 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
528 *insn
++ = BPF_LD_ABS(BPF_B
, fp
->k
);
530 *insn
++ = BPF_ALU32_IMM(BPF_AND
, BPF_REG_A
, 0xf);
532 *insn
++ = BPF_ALU32_IMM(BPF_LSH
, BPF_REG_A
, 2);
534 *insn
++ = BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
536 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_TMP
);
539 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
540 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
542 case BPF_RET
| BPF_A
:
543 case BPF_RET
| BPF_K
:
544 if (BPF_RVAL(fp
->code
) == BPF_K
)
545 *insn
++ = BPF_MOV32_RAW(BPF_K
, BPF_REG_0
,
547 *insn
= BPF_EXIT_INSN();
550 /* Store to stack. */
553 *insn
= BPF_STX_MEM(BPF_W
, BPF_REG_FP
, BPF_CLASS(fp
->code
) ==
554 BPF_ST
? BPF_REG_A
: BPF_REG_X
,
555 -(BPF_MEMWORDS
- fp
->k
) * 4);
558 /* Load from stack. */
559 case BPF_LD
| BPF_MEM
:
560 case BPF_LDX
| BPF_MEM
:
561 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
562 BPF_REG_A
: BPF_REG_X
, BPF_REG_FP
,
563 -(BPF_MEMWORDS
- fp
->k
) * 4);
567 case BPF_LD
| BPF_IMM
:
568 case BPF_LDX
| BPF_IMM
:
569 *insn
= BPF_MOV32_IMM(BPF_CLASS(fp
->code
) == BPF_LD
?
570 BPF_REG_A
: BPF_REG_X
, fp
->k
);
574 case BPF_MISC
| BPF_TAX
:
575 *insn
= BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
579 case BPF_MISC
| BPF_TXA
:
580 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_X
);
583 /* A = skb->len or X = skb->len */
584 case BPF_LD
| BPF_W
| BPF_LEN
:
585 case BPF_LDX
| BPF_W
| BPF_LEN
:
586 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
587 BPF_REG_A
: BPF_REG_X
, BPF_REG_CTX
,
588 offsetof(struct sk_buff
, len
));
591 /* Access seccomp_data fields. */
592 case BPF_LDX
| BPF_ABS
| BPF_W
:
593 /* A = *(u32 *) (ctx + K) */
594 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
, fp
->k
);
597 /* Unknown instruction. */
604 memcpy(new_insn
, tmp_insns
,
605 sizeof(*insn
) * (insn
- tmp_insns
));
606 new_insn
+= insn
- tmp_insns
;
610 /* Only calculating new length. */
611 *new_len
= new_insn
- new_prog
;
616 if (new_flen
!= new_insn
- new_prog
) {
617 new_flen
= new_insn
- new_prog
;
624 BUG_ON(*new_len
!= new_flen
);
633 * As we dont want to clear mem[] array for each packet going through
634 * __bpf_prog_run(), we check that filter loaded by user never try to read
635 * a cell if not previously written, and we check all branches to be sure
636 * a malicious user doesn't try to abuse us.
638 static int check_load_and_stores(const struct sock_filter
*filter
, int flen
)
640 u16
*masks
, memvalid
= 0; /* One bit per cell, 16 cells */
643 BUILD_BUG_ON(BPF_MEMWORDS
> 16);
645 masks
= kmalloc_array(flen
, sizeof(*masks
), GFP_KERNEL
);
649 memset(masks
, 0xff, flen
* sizeof(*masks
));
651 for (pc
= 0; pc
< flen
; pc
++) {
652 memvalid
&= masks
[pc
];
654 switch (filter
[pc
].code
) {
657 memvalid
|= (1 << filter
[pc
].k
);
659 case BPF_LD
| BPF_MEM
:
660 case BPF_LDX
| BPF_MEM
:
661 if (!(memvalid
& (1 << filter
[pc
].k
))) {
666 case BPF_JMP
| BPF_JA
:
667 /* A jump must set masks on target */
668 masks
[pc
+ 1 + filter
[pc
].k
] &= memvalid
;
671 case BPF_JMP
| BPF_JEQ
| BPF_K
:
672 case BPF_JMP
| BPF_JEQ
| BPF_X
:
673 case BPF_JMP
| BPF_JGE
| BPF_K
:
674 case BPF_JMP
| BPF_JGE
| BPF_X
:
675 case BPF_JMP
| BPF_JGT
| BPF_K
:
676 case BPF_JMP
| BPF_JGT
| BPF_X
:
677 case BPF_JMP
| BPF_JSET
| BPF_K
:
678 case BPF_JMP
| BPF_JSET
| BPF_X
:
679 /* A jump must set masks on targets */
680 masks
[pc
+ 1 + filter
[pc
].jt
] &= memvalid
;
681 masks
[pc
+ 1 + filter
[pc
].jf
] &= memvalid
;
691 static bool chk_code_allowed(u16 code_to_probe
)
693 static const bool codes
[] = {
694 /* 32 bit ALU operations */
695 [BPF_ALU
| BPF_ADD
| BPF_K
] = true,
696 [BPF_ALU
| BPF_ADD
| BPF_X
] = true,
697 [BPF_ALU
| BPF_SUB
| BPF_K
] = true,
698 [BPF_ALU
| BPF_SUB
| BPF_X
] = true,
699 [BPF_ALU
| BPF_MUL
| BPF_K
] = true,
700 [BPF_ALU
| BPF_MUL
| BPF_X
] = true,
701 [BPF_ALU
| BPF_DIV
| BPF_K
] = true,
702 [BPF_ALU
| BPF_DIV
| BPF_X
] = true,
703 [BPF_ALU
| BPF_MOD
| BPF_K
] = true,
704 [BPF_ALU
| BPF_MOD
| BPF_X
] = true,
705 [BPF_ALU
| BPF_AND
| BPF_K
] = true,
706 [BPF_ALU
| BPF_AND
| BPF_X
] = true,
707 [BPF_ALU
| BPF_OR
| BPF_K
] = true,
708 [BPF_ALU
| BPF_OR
| BPF_X
] = true,
709 [BPF_ALU
| BPF_XOR
| BPF_K
] = true,
710 [BPF_ALU
| BPF_XOR
| BPF_X
] = true,
711 [BPF_ALU
| BPF_LSH
| BPF_K
] = true,
712 [BPF_ALU
| BPF_LSH
| BPF_X
] = true,
713 [BPF_ALU
| BPF_RSH
| BPF_K
] = true,
714 [BPF_ALU
| BPF_RSH
| BPF_X
] = true,
715 [BPF_ALU
| BPF_NEG
] = true,
716 /* Load instructions */
717 [BPF_LD
| BPF_W
| BPF_ABS
] = true,
718 [BPF_LD
| BPF_H
| BPF_ABS
] = true,
719 [BPF_LD
| BPF_B
| BPF_ABS
] = true,
720 [BPF_LD
| BPF_W
| BPF_LEN
] = true,
721 [BPF_LD
| BPF_W
| BPF_IND
] = true,
722 [BPF_LD
| BPF_H
| BPF_IND
] = true,
723 [BPF_LD
| BPF_B
| BPF_IND
] = true,
724 [BPF_LD
| BPF_IMM
] = true,
725 [BPF_LD
| BPF_MEM
] = true,
726 [BPF_LDX
| BPF_W
| BPF_LEN
] = true,
727 [BPF_LDX
| BPF_B
| BPF_MSH
] = true,
728 [BPF_LDX
| BPF_IMM
] = true,
729 [BPF_LDX
| BPF_MEM
] = true,
730 /* Store instructions */
733 /* Misc instructions */
734 [BPF_MISC
| BPF_TAX
] = true,
735 [BPF_MISC
| BPF_TXA
] = true,
736 /* Return instructions */
737 [BPF_RET
| BPF_K
] = true,
738 [BPF_RET
| BPF_A
] = true,
739 /* Jump instructions */
740 [BPF_JMP
| BPF_JA
] = true,
741 [BPF_JMP
| BPF_JEQ
| BPF_K
] = true,
742 [BPF_JMP
| BPF_JEQ
| BPF_X
] = true,
743 [BPF_JMP
| BPF_JGE
| BPF_K
] = true,
744 [BPF_JMP
| BPF_JGE
| BPF_X
] = true,
745 [BPF_JMP
| BPF_JGT
| BPF_K
] = true,
746 [BPF_JMP
| BPF_JGT
| BPF_X
] = true,
747 [BPF_JMP
| BPF_JSET
| BPF_K
] = true,
748 [BPF_JMP
| BPF_JSET
| BPF_X
] = true,
751 if (code_to_probe
>= ARRAY_SIZE(codes
))
754 return codes
[code_to_probe
];
757 static bool bpf_check_basics_ok(const struct sock_filter
*filter
,
762 if (flen
== 0 || flen
> BPF_MAXINSNS
)
769 * bpf_check_classic - verify socket filter code
770 * @filter: filter to verify
771 * @flen: length of filter
773 * Check the user's filter code. If we let some ugly
774 * filter code slip through kaboom! The filter must contain
775 * no references or jumps that are out of range, no illegal
776 * instructions, and must end with a RET instruction.
778 * All jumps are forward as they are not signed.
780 * Returns 0 if the rule set is legal or -EINVAL if not.
782 static int bpf_check_classic(const struct sock_filter
*filter
,
788 /* Check the filter code now */
789 for (pc
= 0; pc
< flen
; pc
++) {
790 const struct sock_filter
*ftest
= &filter
[pc
];
792 /* May we actually operate on this code? */
793 if (!chk_code_allowed(ftest
->code
))
796 /* Some instructions need special checks */
797 switch (ftest
->code
) {
798 case BPF_ALU
| BPF_DIV
| BPF_K
:
799 case BPF_ALU
| BPF_MOD
| BPF_K
:
800 /* Check for division by zero */
804 case BPF_ALU
| BPF_LSH
| BPF_K
:
805 case BPF_ALU
| BPF_RSH
| BPF_K
:
809 case BPF_LD
| BPF_MEM
:
810 case BPF_LDX
| BPF_MEM
:
813 /* Check for invalid memory addresses */
814 if (ftest
->k
>= BPF_MEMWORDS
)
817 case BPF_JMP
| BPF_JA
:
818 /* Note, the large ftest->k might cause loops.
819 * Compare this with conditional jumps below,
820 * where offsets are limited. --ANK (981016)
822 if (ftest
->k
>= (unsigned int)(flen
- pc
- 1))
825 case BPF_JMP
| BPF_JEQ
| BPF_K
:
826 case BPF_JMP
| BPF_JEQ
| BPF_X
:
827 case BPF_JMP
| BPF_JGE
| BPF_K
:
828 case BPF_JMP
| BPF_JGE
| BPF_X
:
829 case BPF_JMP
| BPF_JGT
| BPF_K
:
830 case BPF_JMP
| BPF_JGT
| BPF_X
:
831 case BPF_JMP
| BPF_JSET
| BPF_K
:
832 case BPF_JMP
| BPF_JSET
| BPF_X
:
833 /* Both conditionals must be safe */
834 if (pc
+ ftest
->jt
+ 1 >= flen
||
835 pc
+ ftest
->jf
+ 1 >= flen
)
838 case BPF_LD
| BPF_W
| BPF_ABS
:
839 case BPF_LD
| BPF_H
| BPF_ABS
:
840 case BPF_LD
| BPF_B
| BPF_ABS
:
842 if (bpf_anc_helper(ftest
) & BPF_ANC
)
844 /* Ancillary operation unknown or unsupported */
845 if (anc_found
== false && ftest
->k
>= SKF_AD_OFF
)
850 /* Last instruction must be a RET code */
851 switch (filter
[flen
- 1].code
) {
852 case BPF_RET
| BPF_K
:
853 case BPF_RET
| BPF_A
:
854 return check_load_and_stores(filter
, flen
);
860 static int bpf_prog_store_orig_filter(struct bpf_prog
*fp
,
861 const struct sock_fprog
*fprog
)
863 unsigned int fsize
= bpf_classic_proglen(fprog
);
864 struct sock_fprog_kern
*fkprog
;
866 fp
->orig_prog
= kmalloc(sizeof(*fkprog
), GFP_KERNEL
);
870 fkprog
= fp
->orig_prog
;
871 fkprog
->len
= fprog
->len
;
873 fkprog
->filter
= kmemdup(fp
->insns
, fsize
,
874 GFP_KERNEL
| __GFP_NOWARN
);
875 if (!fkprog
->filter
) {
876 kfree(fp
->orig_prog
);
883 static void bpf_release_orig_filter(struct bpf_prog
*fp
)
885 struct sock_fprog_kern
*fprog
= fp
->orig_prog
;
888 kfree(fprog
->filter
);
893 static void __bpf_prog_release(struct bpf_prog
*prog
)
895 if (prog
->type
== BPF_PROG_TYPE_SOCKET_FILTER
) {
898 bpf_release_orig_filter(prog
);
903 static void __sk_filter_release(struct sk_filter
*fp
)
905 __bpf_prog_release(fp
->prog
);
910 * sk_filter_release_rcu - Release a socket filter by rcu_head
911 * @rcu: rcu_head that contains the sk_filter to free
913 static void sk_filter_release_rcu(struct rcu_head
*rcu
)
915 struct sk_filter
*fp
= container_of(rcu
, struct sk_filter
, rcu
);
917 __sk_filter_release(fp
);
921 * sk_filter_release - release a socket filter
922 * @fp: filter to remove
924 * Remove a filter from a socket and release its resources.
926 static void sk_filter_release(struct sk_filter
*fp
)
928 if (atomic_dec_and_test(&fp
->refcnt
))
929 call_rcu(&fp
->rcu
, sk_filter_release_rcu
);
932 void sk_filter_uncharge(struct sock
*sk
, struct sk_filter
*fp
)
934 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
936 atomic_sub(filter_size
, &sk
->sk_omem_alloc
);
937 sk_filter_release(fp
);
940 /* try to charge the socket memory if there is space available
941 * return true on success
943 bool sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
945 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
947 /* same check as in sock_kmalloc() */
948 if (filter_size
<= sysctl_optmem_max
&&
949 atomic_read(&sk
->sk_omem_alloc
) + filter_size
< sysctl_optmem_max
) {
950 atomic_inc(&fp
->refcnt
);
951 atomic_add(filter_size
, &sk
->sk_omem_alloc
);
957 static struct bpf_prog
*bpf_migrate_filter(struct bpf_prog
*fp
)
959 struct sock_filter
*old_prog
;
960 struct bpf_prog
*old_fp
;
961 int err
, new_len
, old_len
= fp
->len
;
963 /* We are free to overwrite insns et al right here as it
964 * won't be used at this point in time anymore internally
965 * after the migration to the internal BPF instruction
968 BUILD_BUG_ON(sizeof(struct sock_filter
) !=
969 sizeof(struct bpf_insn
));
971 /* Conversion cannot happen on overlapping memory areas,
972 * so we need to keep the user BPF around until the 2nd
973 * pass. At this time, the user BPF is stored in fp->insns.
975 old_prog
= kmemdup(fp
->insns
, old_len
* sizeof(struct sock_filter
),
976 GFP_KERNEL
| __GFP_NOWARN
);
982 /* 1st pass: calculate the new program length. */
983 err
= bpf_convert_filter(old_prog
, old_len
, NULL
, &new_len
);
987 /* Expand fp for appending the new filter representation. */
989 fp
= bpf_prog_realloc(old_fp
, bpf_prog_size(new_len
), 0);
991 /* The old_fp is still around in case we couldn't
992 * allocate new memory, so uncharge on that one.
1001 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1002 err
= bpf_convert_filter(old_prog
, old_len
, fp
->insnsi
, &new_len
);
1004 /* 2nd bpf_convert_filter() can fail only if it fails
1005 * to allocate memory, remapping must succeed. Note,
1006 * that at this time old_fp has already been released
1011 /* We are guaranteed to never error here with cBPF to eBPF
1012 * transitions, since there's no issue with type compatibility
1013 * checks on program arrays.
1015 fp
= bpf_prog_select_runtime(fp
, &err
);
1023 __bpf_prog_release(fp
);
1024 return ERR_PTR(err
);
1027 static struct bpf_prog
*bpf_prepare_filter(struct bpf_prog
*fp
,
1028 bpf_aux_classic_check_t trans
)
1032 fp
->bpf_func
= NULL
;
1035 err
= bpf_check_classic(fp
->insns
, fp
->len
);
1037 __bpf_prog_release(fp
);
1038 return ERR_PTR(err
);
1041 /* There might be additional checks and transformations
1042 * needed on classic filters, f.e. in case of seccomp.
1045 err
= trans(fp
->insns
, fp
->len
);
1047 __bpf_prog_release(fp
);
1048 return ERR_PTR(err
);
1052 /* Probe if we can JIT compile the filter and if so, do
1053 * the compilation of the filter.
1055 bpf_jit_compile(fp
);
1057 /* JIT compiler couldn't process this filter, so do the
1058 * internal BPF translation for the optimized interpreter.
1061 fp
= bpf_migrate_filter(fp
);
1067 * bpf_prog_create - create an unattached filter
1068 * @pfp: the unattached filter that is created
1069 * @fprog: the filter program
1071 * Create a filter independent of any socket. We first run some
1072 * sanity checks on it to make sure it does not explode on us later.
1073 * If an error occurs or there is insufficient memory for the filter
1074 * a negative errno code is returned. On success the return is zero.
1076 int bpf_prog_create(struct bpf_prog
**pfp
, struct sock_fprog_kern
*fprog
)
1078 unsigned int fsize
= bpf_classic_proglen(fprog
);
1079 struct bpf_prog
*fp
;
1081 /* Make sure new filter is there and in the right amounts. */
1082 if (!bpf_check_basics_ok(fprog
->filter
, fprog
->len
))
1085 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1089 memcpy(fp
->insns
, fprog
->filter
, fsize
);
1091 fp
->len
= fprog
->len
;
1092 /* Since unattached filters are not copied back to user
1093 * space through sk_get_filter(), we do not need to hold
1094 * a copy here, and can spare us the work.
1096 fp
->orig_prog
= NULL
;
1098 /* bpf_prepare_filter() already takes care of freeing
1099 * memory in case something goes wrong.
1101 fp
= bpf_prepare_filter(fp
, NULL
);
1108 EXPORT_SYMBOL_GPL(bpf_prog_create
);
1111 * bpf_prog_create_from_user - create an unattached filter from user buffer
1112 * @pfp: the unattached filter that is created
1113 * @fprog: the filter program
1114 * @trans: post-classic verifier transformation handler
1115 * @save_orig: save classic BPF program
1117 * This function effectively does the same as bpf_prog_create(), only
1118 * that it builds up its insns buffer from user space provided buffer.
1119 * It also allows for passing a bpf_aux_classic_check_t handler.
1121 int bpf_prog_create_from_user(struct bpf_prog
**pfp
, struct sock_fprog
*fprog
,
1122 bpf_aux_classic_check_t trans
, bool save_orig
)
1124 unsigned int fsize
= bpf_classic_proglen(fprog
);
1125 struct bpf_prog
*fp
;
1128 /* Make sure new filter is there and in the right amounts. */
1129 if (!bpf_check_basics_ok(fprog
->filter
, fprog
->len
))
1132 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1136 if (copy_from_user(fp
->insns
, fprog
->filter
, fsize
)) {
1137 __bpf_prog_free(fp
);
1141 fp
->len
= fprog
->len
;
1142 fp
->orig_prog
= NULL
;
1145 err
= bpf_prog_store_orig_filter(fp
, fprog
);
1147 __bpf_prog_free(fp
);
1152 /* bpf_prepare_filter() already takes care of freeing
1153 * memory in case something goes wrong.
1155 fp
= bpf_prepare_filter(fp
, trans
);
1162 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user
);
1164 void bpf_prog_destroy(struct bpf_prog
*fp
)
1166 __bpf_prog_release(fp
);
1168 EXPORT_SYMBOL_GPL(bpf_prog_destroy
);
1170 static int __sk_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1172 struct sk_filter
*fp
, *old_fp
;
1174 fp
= kmalloc(sizeof(*fp
), GFP_KERNEL
);
1179 atomic_set(&fp
->refcnt
, 0);
1181 if (!sk_filter_charge(sk
, fp
)) {
1186 old_fp
= rcu_dereference_protected(sk
->sk_filter
,
1187 lockdep_sock_is_held(sk
));
1188 rcu_assign_pointer(sk
->sk_filter
, fp
);
1191 sk_filter_uncharge(sk
, old_fp
);
1196 static int __reuseport_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1198 struct bpf_prog
*old_prog
;
1201 if (bpf_prog_size(prog
->len
) > sysctl_optmem_max
)
1204 if (sk_unhashed(sk
) && sk
->sk_reuseport
) {
1205 err
= reuseport_alloc(sk
);
1208 } else if (!rcu_access_pointer(sk
->sk_reuseport_cb
)) {
1209 /* The socket wasn't bound with SO_REUSEPORT */
1213 old_prog
= reuseport_attach_prog(sk
, prog
);
1215 bpf_prog_destroy(old_prog
);
1221 struct bpf_prog
*__get_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1223 unsigned int fsize
= bpf_classic_proglen(fprog
);
1224 struct bpf_prog
*prog
;
1227 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1228 return ERR_PTR(-EPERM
);
1230 /* Make sure new filter is there and in the right amounts. */
1231 if (!bpf_check_basics_ok(fprog
->filter
, fprog
->len
))
1232 return ERR_PTR(-EINVAL
);
1234 prog
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1236 return ERR_PTR(-ENOMEM
);
1238 if (copy_from_user(prog
->insns
, fprog
->filter
, fsize
)) {
1239 __bpf_prog_free(prog
);
1240 return ERR_PTR(-EFAULT
);
1243 prog
->len
= fprog
->len
;
1245 err
= bpf_prog_store_orig_filter(prog
, fprog
);
1247 __bpf_prog_free(prog
);
1248 return ERR_PTR(-ENOMEM
);
1251 /* bpf_prepare_filter() already takes care of freeing
1252 * memory in case something goes wrong.
1254 return bpf_prepare_filter(prog
, NULL
);
1258 * sk_attach_filter - attach a socket filter
1259 * @fprog: the filter program
1260 * @sk: the socket to use
1262 * Attach the user's filter code. We first run some sanity checks on
1263 * it to make sure it does not explode on us later. If an error
1264 * occurs or there is insufficient memory for the filter a negative
1265 * errno code is returned. On success the return is zero.
1267 int sk_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1269 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1273 return PTR_ERR(prog
);
1275 err
= __sk_attach_prog(prog
, sk
);
1277 __bpf_prog_release(prog
);
1283 EXPORT_SYMBOL_GPL(sk_attach_filter
);
1285 int sk_reuseport_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1287 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1291 return PTR_ERR(prog
);
1293 err
= __reuseport_attach_prog(prog
, sk
);
1295 __bpf_prog_release(prog
);
1302 static struct bpf_prog
*__get_bpf(u32 ufd
, struct sock
*sk
)
1304 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1305 return ERR_PTR(-EPERM
);
1307 return bpf_prog_get_type(ufd
, BPF_PROG_TYPE_SOCKET_FILTER
);
1310 int sk_attach_bpf(u32 ufd
, struct sock
*sk
)
1312 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1316 return PTR_ERR(prog
);
1318 err
= __sk_attach_prog(prog
, sk
);
1327 int sk_reuseport_attach_bpf(u32 ufd
, struct sock
*sk
)
1329 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1333 return PTR_ERR(prog
);
1335 err
= __reuseport_attach_prog(prog
, sk
);
1344 struct bpf_scratchpad
{
1346 __be32 diff
[MAX_BPF_STACK
/ sizeof(__be32
)];
1347 u8 buff
[MAX_BPF_STACK
];
1351 static DEFINE_PER_CPU(struct bpf_scratchpad
, bpf_sp
);
1353 static inline int bpf_try_make_writable(struct sk_buff
*skb
,
1354 unsigned int write_len
)
1358 err
= skb_ensure_writable(skb
, write_len
);
1359 bpf_compute_data_end(skb
);
1364 static inline void bpf_push_mac_rcsum(struct sk_buff
*skb
)
1366 if (skb_at_tc_ingress(skb
))
1367 skb_postpush_rcsum(skb
, skb_mac_header(skb
), skb
->mac_len
);
1370 static inline void bpf_pull_mac_rcsum(struct sk_buff
*skb
)
1372 if (skb_at_tc_ingress(skb
))
1373 skb_postpull_rcsum(skb
, skb_mac_header(skb
), skb
->mac_len
);
1376 static u64
bpf_skb_store_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 flags
)
1378 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1379 unsigned int offset
= (unsigned int) r2
;
1380 void *from
= (void *) (long) r3
;
1381 unsigned int len
= (unsigned int) r4
;
1384 if (unlikely(flags
& ~(BPF_F_RECOMPUTE_CSUM
| BPF_F_INVALIDATE_HASH
)))
1386 if (unlikely(offset
> 0xffff))
1388 if (unlikely(bpf_try_make_writable(skb
, offset
+ len
)))
1391 ptr
= skb
->data
+ offset
;
1392 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1393 __skb_postpull_rcsum(skb
, ptr
, len
, offset
);
1395 memcpy(ptr
, from
, len
);
1397 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1398 __skb_postpush_rcsum(skb
, ptr
, len
, offset
);
1399 if (flags
& BPF_F_INVALIDATE_HASH
)
1400 skb_clear_hash(skb
);
1405 static const struct bpf_func_proto bpf_skb_store_bytes_proto
= {
1406 .func
= bpf_skb_store_bytes
,
1408 .ret_type
= RET_INTEGER
,
1409 .arg1_type
= ARG_PTR_TO_CTX
,
1410 .arg2_type
= ARG_ANYTHING
,
1411 .arg3_type
= ARG_PTR_TO_STACK
,
1412 .arg4_type
= ARG_CONST_STACK_SIZE
,
1413 .arg5_type
= ARG_ANYTHING
,
1416 static u64
bpf_skb_load_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1418 const struct sk_buff
*skb
= (const struct sk_buff
*)(unsigned long) r1
;
1419 unsigned int offset
= (unsigned int) r2
;
1420 void *to
= (void *)(unsigned long) r3
;
1421 unsigned int len
= (unsigned int) r4
;
1424 if (unlikely(offset
> 0xffff))
1427 ptr
= skb_header_pointer(skb
, offset
, len
, to
);
1431 memcpy(to
, ptr
, len
);
1439 static const struct bpf_func_proto bpf_skb_load_bytes_proto
= {
1440 .func
= bpf_skb_load_bytes
,
1442 .ret_type
= RET_INTEGER
,
1443 .arg1_type
= ARG_PTR_TO_CTX
,
1444 .arg2_type
= ARG_ANYTHING
,
1445 .arg3_type
= ARG_PTR_TO_RAW_STACK
,
1446 .arg4_type
= ARG_CONST_STACK_SIZE
,
1449 static u64
bpf_l3_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1451 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1452 unsigned int offset
= (unsigned int) r2
;
1455 if (unlikely(flags
& ~(BPF_F_HDR_FIELD_MASK
)))
1457 if (unlikely(offset
> 0xffff || offset
& 1))
1459 if (unlikely(bpf_try_make_writable(skb
, offset
+ sizeof(*ptr
))))
1462 ptr
= (__sum16
*)(skb
->data
+ offset
);
1463 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1465 if (unlikely(from
!= 0))
1468 csum_replace_by_diff(ptr
, to
);
1471 csum_replace2(ptr
, from
, to
);
1474 csum_replace4(ptr
, from
, to
);
1483 static const struct bpf_func_proto bpf_l3_csum_replace_proto
= {
1484 .func
= bpf_l3_csum_replace
,
1486 .ret_type
= RET_INTEGER
,
1487 .arg1_type
= ARG_PTR_TO_CTX
,
1488 .arg2_type
= ARG_ANYTHING
,
1489 .arg3_type
= ARG_ANYTHING
,
1490 .arg4_type
= ARG_ANYTHING
,
1491 .arg5_type
= ARG_ANYTHING
,
1494 static u64
bpf_l4_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1496 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1497 bool is_pseudo
= flags
& BPF_F_PSEUDO_HDR
;
1498 bool is_mmzero
= flags
& BPF_F_MARK_MANGLED_0
;
1499 unsigned int offset
= (unsigned int) r2
;
1502 if (unlikely(flags
& ~(BPF_F_MARK_MANGLED_0
| BPF_F_PSEUDO_HDR
|
1503 BPF_F_HDR_FIELD_MASK
)))
1505 if (unlikely(offset
> 0xffff || offset
& 1))
1507 if (unlikely(bpf_try_make_writable(skb
, offset
+ sizeof(*ptr
))))
1510 ptr
= (__sum16
*)(skb
->data
+ offset
);
1511 if (is_mmzero
&& !*ptr
)
1514 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1516 if (unlikely(from
!= 0))
1519 inet_proto_csum_replace_by_diff(ptr
, skb
, to
, is_pseudo
);
1522 inet_proto_csum_replace2(ptr
, skb
, from
, to
, is_pseudo
);
1525 inet_proto_csum_replace4(ptr
, skb
, from
, to
, is_pseudo
);
1531 if (is_mmzero
&& !*ptr
)
1532 *ptr
= CSUM_MANGLED_0
;
1536 static const struct bpf_func_proto bpf_l4_csum_replace_proto
= {
1537 .func
= bpf_l4_csum_replace
,
1539 .ret_type
= RET_INTEGER
,
1540 .arg1_type
= ARG_PTR_TO_CTX
,
1541 .arg2_type
= ARG_ANYTHING
,
1542 .arg3_type
= ARG_ANYTHING
,
1543 .arg4_type
= ARG_ANYTHING
,
1544 .arg5_type
= ARG_ANYTHING
,
1547 static u64
bpf_csum_diff(u64 r1
, u64 from_size
, u64 r3
, u64 to_size
, u64 seed
)
1549 struct bpf_scratchpad
*sp
= this_cpu_ptr(&bpf_sp
);
1550 u64 diff_size
= from_size
+ to_size
;
1551 __be32
*from
= (__be32
*) (long) r1
;
1552 __be32
*to
= (__be32
*) (long) r3
;
1555 /* This is quite flexible, some examples:
1557 * from_size == 0, to_size > 0, seed := csum --> pushing data
1558 * from_size > 0, to_size == 0, seed := csum --> pulling data
1559 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1561 * Even for diffing, from_size and to_size don't need to be equal.
1563 if (unlikely(((from_size
| to_size
) & (sizeof(__be32
) - 1)) ||
1564 diff_size
> sizeof(sp
->diff
)))
1567 for (i
= 0; i
< from_size
/ sizeof(__be32
); i
++, j
++)
1568 sp
->diff
[j
] = ~from
[i
];
1569 for (i
= 0; i
< to_size
/ sizeof(__be32
); i
++, j
++)
1570 sp
->diff
[j
] = to
[i
];
1572 return csum_partial(sp
->diff
, diff_size
, seed
);
1575 static const struct bpf_func_proto bpf_csum_diff_proto
= {
1576 .func
= bpf_csum_diff
,
1578 .ret_type
= RET_INTEGER
,
1579 .arg1_type
= ARG_PTR_TO_STACK
,
1580 .arg2_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1581 .arg3_type
= ARG_PTR_TO_STACK
,
1582 .arg4_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1583 .arg5_type
= ARG_ANYTHING
,
1586 static inline int __bpf_rx_skb(struct net_device
*dev
, struct sk_buff
*skb
)
1588 return dev_forward_skb(dev
, skb
);
1591 static inline int __bpf_tx_skb(struct net_device
*dev
, struct sk_buff
*skb
)
1595 if (unlikely(__this_cpu_read(xmit_recursion
) > XMIT_RECURSION_LIMIT
)) {
1596 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
1603 __this_cpu_inc(xmit_recursion
);
1604 ret
= dev_queue_xmit(skb
);
1605 __this_cpu_dec(xmit_recursion
);
1610 static u64
bpf_clone_redirect(u64 r1
, u64 ifindex
, u64 flags
, u64 r4
, u64 r5
)
1612 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1613 struct net_device
*dev
;
1615 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1618 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ifindex
);
1622 skb
= skb_clone(skb
, GFP_ATOMIC
);
1626 bpf_push_mac_rcsum(skb
);
1628 return flags
& BPF_F_INGRESS
?
1629 __bpf_rx_skb(dev
, skb
) : __bpf_tx_skb(dev
, skb
);
1632 static const struct bpf_func_proto bpf_clone_redirect_proto
= {
1633 .func
= bpf_clone_redirect
,
1635 .ret_type
= RET_INTEGER
,
1636 .arg1_type
= ARG_PTR_TO_CTX
,
1637 .arg2_type
= ARG_ANYTHING
,
1638 .arg3_type
= ARG_ANYTHING
,
1641 struct redirect_info
{
1646 static DEFINE_PER_CPU(struct redirect_info
, redirect_info
);
1648 static u64
bpf_redirect(u64 ifindex
, u64 flags
, u64 r3
, u64 r4
, u64 r5
)
1650 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1652 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1655 ri
->ifindex
= ifindex
;
1658 return TC_ACT_REDIRECT
;
1661 int skb_do_redirect(struct sk_buff
*skb
)
1663 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1664 struct net_device
*dev
;
1666 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ri
->ifindex
);
1668 if (unlikely(!dev
)) {
1673 bpf_push_mac_rcsum(skb
);
1675 return ri
->flags
& BPF_F_INGRESS
?
1676 __bpf_rx_skb(dev
, skb
) : __bpf_tx_skb(dev
, skb
);
1679 static const struct bpf_func_proto bpf_redirect_proto
= {
1680 .func
= bpf_redirect
,
1682 .ret_type
= RET_INTEGER
,
1683 .arg1_type
= ARG_ANYTHING
,
1684 .arg2_type
= ARG_ANYTHING
,
1687 static u64
bpf_get_cgroup_classid(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1689 return task_get_classid((struct sk_buff
*) (unsigned long) r1
);
1692 static const struct bpf_func_proto bpf_get_cgroup_classid_proto
= {
1693 .func
= bpf_get_cgroup_classid
,
1695 .ret_type
= RET_INTEGER
,
1696 .arg1_type
= ARG_PTR_TO_CTX
,
1699 static u64
bpf_get_route_realm(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1701 return dst_tclassid((struct sk_buff
*) (unsigned long) r1
);
1704 static const struct bpf_func_proto bpf_get_route_realm_proto
= {
1705 .func
= bpf_get_route_realm
,
1707 .ret_type
= RET_INTEGER
,
1708 .arg1_type
= ARG_PTR_TO_CTX
,
1711 static u64
bpf_get_hash_recalc(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1713 /* If skb_clear_hash() was called due to mangling, we can
1714 * trigger SW recalculation here. Later access to hash
1715 * can then use the inline skb->hash via context directly
1716 * instead of calling this helper again.
1718 return skb_get_hash((struct sk_buff
*) (unsigned long) r1
);
1721 static const struct bpf_func_proto bpf_get_hash_recalc_proto
= {
1722 .func
= bpf_get_hash_recalc
,
1724 .ret_type
= RET_INTEGER
,
1725 .arg1_type
= ARG_PTR_TO_CTX
,
1728 static u64
bpf_skb_vlan_push(u64 r1
, u64 r2
, u64 vlan_tci
, u64 r4
, u64 r5
)
1730 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1731 __be16 vlan_proto
= (__force __be16
) r2
;
1734 if (unlikely(vlan_proto
!= htons(ETH_P_8021Q
) &&
1735 vlan_proto
!= htons(ETH_P_8021AD
)))
1736 vlan_proto
= htons(ETH_P_8021Q
);
1738 bpf_push_mac_rcsum(skb
);
1739 ret
= skb_vlan_push(skb
, vlan_proto
, vlan_tci
);
1740 bpf_pull_mac_rcsum(skb
);
1742 bpf_compute_data_end(skb
);
1746 const struct bpf_func_proto bpf_skb_vlan_push_proto
= {
1747 .func
= bpf_skb_vlan_push
,
1749 .ret_type
= RET_INTEGER
,
1750 .arg1_type
= ARG_PTR_TO_CTX
,
1751 .arg2_type
= ARG_ANYTHING
,
1752 .arg3_type
= ARG_ANYTHING
,
1754 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto
);
1756 static u64
bpf_skb_vlan_pop(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1758 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1761 bpf_push_mac_rcsum(skb
);
1762 ret
= skb_vlan_pop(skb
);
1763 bpf_pull_mac_rcsum(skb
);
1765 bpf_compute_data_end(skb
);
1769 const struct bpf_func_proto bpf_skb_vlan_pop_proto
= {
1770 .func
= bpf_skb_vlan_pop
,
1772 .ret_type
= RET_INTEGER
,
1773 .arg1_type
= ARG_PTR_TO_CTX
,
1775 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto
);
1777 static int bpf_skb_generic_push(struct sk_buff
*skb
, u32 off
, u32 len
)
1779 /* Caller already did skb_cow() with len as headroom,
1780 * so no need to do it here.
1783 memmove(skb
->data
, skb
->data
+ len
, off
);
1784 memset(skb
->data
+ off
, 0, len
);
1786 /* No skb_postpush_rcsum(skb, skb->data + off, len)
1787 * needed here as it does not change the skb->csum
1788 * result for checksum complete when summing over
1794 static int bpf_skb_generic_pop(struct sk_buff
*skb
, u32 off
, u32 len
)
1796 /* skb_ensure_writable() is not needed here, as we're
1797 * already working on an uncloned skb.
1799 if (unlikely(!pskb_may_pull(skb
, off
+ len
)))
1802 skb_postpull_rcsum(skb
, skb
->data
+ off
, len
);
1803 memmove(skb
->data
+ len
, skb
->data
, off
);
1804 __skb_pull(skb
, len
);
1809 static int bpf_skb_net_hdr_push(struct sk_buff
*skb
, u32 off
, u32 len
)
1811 bool trans_same
= skb
->transport_header
== skb
->network_header
;
1814 /* There's no need for __skb_push()/__skb_pull() pair to
1815 * get to the start of the mac header as we're guaranteed
1816 * to always start from here under eBPF.
1818 ret
= bpf_skb_generic_push(skb
, off
, len
);
1820 skb
->mac_header
-= len
;
1821 skb
->network_header
-= len
;
1823 skb
->transport_header
= skb
->network_header
;
1829 static int bpf_skb_net_hdr_pop(struct sk_buff
*skb
, u32 off
, u32 len
)
1831 bool trans_same
= skb
->transport_header
== skb
->network_header
;
1834 /* Same here, __skb_push()/__skb_pull() pair not needed. */
1835 ret
= bpf_skb_generic_pop(skb
, off
, len
);
1837 skb
->mac_header
+= len
;
1838 skb
->network_header
+= len
;
1840 skb
->transport_header
= skb
->network_header
;
1846 static int bpf_skb_proto_4_to_6(struct sk_buff
*skb
)
1848 const u32 len_diff
= sizeof(struct ipv6hdr
) - sizeof(struct iphdr
);
1849 u32 off
= skb
->network_header
- skb
->mac_header
;
1852 ret
= skb_cow(skb
, len_diff
);
1853 if (unlikely(ret
< 0))
1856 ret
= bpf_skb_net_hdr_push(skb
, off
, len_diff
);
1857 if (unlikely(ret
< 0))
1860 if (skb_is_gso(skb
)) {
1861 /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV4 needs to
1862 * be changed into SKB_GSO_TCPV6.
1864 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV4
) {
1865 skb_shinfo(skb
)->gso_type
&= ~SKB_GSO_TCPV4
;
1866 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCPV6
;
1869 /* Due to IPv6 header, MSS needs to be downgraded. */
1870 skb_shinfo(skb
)->gso_size
-= len_diff
;
1871 /* Header must be checked, and gso_segs recomputed. */
1872 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
1873 skb_shinfo(skb
)->gso_segs
= 0;
1876 skb
->protocol
= htons(ETH_P_IPV6
);
1877 skb_clear_hash(skb
);
1882 static int bpf_skb_proto_6_to_4(struct sk_buff
*skb
)
1884 const u32 len_diff
= sizeof(struct ipv6hdr
) - sizeof(struct iphdr
);
1885 u32 off
= skb
->network_header
- skb
->mac_header
;
1888 ret
= skb_unclone(skb
, GFP_ATOMIC
);
1889 if (unlikely(ret
< 0))
1892 ret
= bpf_skb_net_hdr_pop(skb
, off
, len_diff
);
1893 if (unlikely(ret
< 0))
1896 if (skb_is_gso(skb
)) {
1897 /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV6 needs to
1898 * be changed into SKB_GSO_TCPV4.
1900 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
) {
1901 skb_shinfo(skb
)->gso_type
&= ~SKB_GSO_TCPV6
;
1902 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCPV4
;
1905 /* Due to IPv4 header, MSS can be upgraded. */
1906 skb_shinfo(skb
)->gso_size
+= len_diff
;
1907 /* Header must be checked, and gso_segs recomputed. */
1908 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
1909 skb_shinfo(skb
)->gso_segs
= 0;
1912 skb
->protocol
= htons(ETH_P_IP
);
1913 skb_clear_hash(skb
);
1918 static int bpf_skb_proto_xlat(struct sk_buff
*skb
, __be16 to_proto
)
1920 __be16 from_proto
= skb
->protocol
;
1922 if (from_proto
== htons(ETH_P_IP
) &&
1923 to_proto
== htons(ETH_P_IPV6
))
1924 return bpf_skb_proto_4_to_6(skb
);
1926 if (from_proto
== htons(ETH_P_IPV6
) &&
1927 to_proto
== htons(ETH_P_IP
))
1928 return bpf_skb_proto_6_to_4(skb
);
1933 static u64
bpf_skb_change_proto(u64 r1
, u64 r2
, u64 flags
, u64 r4
, u64 r5
)
1935 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1936 __be16 proto
= (__force __be16
) r2
;
1939 if (unlikely(flags
))
1942 /* General idea is that this helper does the basic groundwork
1943 * needed for changing the protocol, and eBPF program fills the
1944 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
1945 * and other helpers, rather than passing a raw buffer here.
1947 * The rationale is to keep this minimal and without a need to
1948 * deal with raw packet data. F.e. even if we would pass buffers
1949 * here, the program still needs to call the bpf_lX_csum_replace()
1950 * helpers anyway. Plus, this way we keep also separation of
1951 * concerns, since f.e. bpf_skb_store_bytes() should only take
1954 * Currently, additional options and extension header space are
1955 * not supported, but flags register is reserved so we can adapt
1956 * that. For offloads, we mark packet as dodgy, so that headers
1957 * need to be verified first.
1959 ret
= bpf_skb_proto_xlat(skb
, proto
);
1960 bpf_compute_data_end(skb
);
1964 static const struct bpf_func_proto bpf_skb_change_proto_proto
= {
1965 .func
= bpf_skb_change_proto
,
1967 .ret_type
= RET_INTEGER
,
1968 .arg1_type
= ARG_PTR_TO_CTX
,
1969 .arg2_type
= ARG_ANYTHING
,
1970 .arg3_type
= ARG_ANYTHING
,
1973 static u64
bpf_skb_change_type(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1975 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1978 /* We only allow a restricted subset to be changed for now. */
1979 if (unlikely(skb
->pkt_type
> PACKET_OTHERHOST
||
1980 pkt_type
> PACKET_OTHERHOST
))
1983 skb
->pkt_type
= pkt_type
;
1987 static const struct bpf_func_proto bpf_skb_change_type_proto
= {
1988 .func
= bpf_skb_change_type
,
1990 .ret_type
= RET_INTEGER
,
1991 .arg1_type
= ARG_PTR_TO_CTX
,
1992 .arg2_type
= ARG_ANYTHING
,
1995 bool bpf_helper_changes_skb_data(void *func
)
1997 if (func
== bpf_skb_vlan_push
)
1999 if (func
== bpf_skb_vlan_pop
)
2001 if (func
== bpf_skb_store_bytes
)
2003 if (func
== bpf_skb_change_proto
)
2005 if (func
== bpf_l3_csum_replace
)
2007 if (func
== bpf_l4_csum_replace
)
2013 static unsigned long bpf_skb_copy(void *dst_buff
, const void *skb
,
2014 unsigned long off
, unsigned long len
)
2016 void *ptr
= skb_header_pointer(skb
, off
, len
, dst_buff
);
2020 if (ptr
!= dst_buff
)
2021 memcpy(dst_buff
, ptr
, len
);
2026 static u64
bpf_skb_event_output(u64 r1
, u64 r2
, u64 flags
, u64 r4
,
2029 struct sk_buff
*skb
= (struct sk_buff
*)(long) r1
;
2030 struct bpf_map
*map
= (struct bpf_map
*)(long) r2
;
2031 u64 skb_size
= (flags
& BPF_F_CTXLEN_MASK
) >> 32;
2032 void *meta
= (void *)(long) r4
;
2034 if (unlikely(flags
& ~(BPF_F_CTXLEN_MASK
| BPF_F_INDEX_MASK
)))
2036 if (unlikely(skb_size
> skb
->len
))
2039 return bpf_event_output(map
, flags
, meta
, meta_size
, skb
, skb_size
,
2043 static const struct bpf_func_proto bpf_skb_event_output_proto
= {
2044 .func
= bpf_skb_event_output
,
2046 .ret_type
= RET_INTEGER
,
2047 .arg1_type
= ARG_PTR_TO_CTX
,
2048 .arg2_type
= ARG_CONST_MAP_PTR
,
2049 .arg3_type
= ARG_ANYTHING
,
2050 .arg4_type
= ARG_PTR_TO_STACK
,
2051 .arg5_type
= ARG_CONST_STACK_SIZE
,
2054 static unsigned short bpf_tunnel_key_af(u64 flags
)
2056 return flags
& BPF_F_TUNINFO_IPV6
? AF_INET6
: AF_INET
;
2059 static u64
bpf_skb_get_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
2061 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
2062 struct bpf_tunnel_key
*to
= (struct bpf_tunnel_key
*) (long) r2
;
2063 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
2064 u8 compat
[sizeof(struct bpf_tunnel_key
)];
2068 if (unlikely(!info
|| (flags
& ~(BPF_F_TUNINFO_IPV6
)))) {
2072 if (ip_tunnel_info_af(info
) != bpf_tunnel_key_af(flags
)) {
2076 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
2079 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
2080 case offsetof(struct bpf_tunnel_key
, tunnel_ext
):
2082 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
2083 /* Fixup deprecated structure layouts here, so we have
2084 * a common path later on.
2086 if (ip_tunnel_info_af(info
) != AF_INET
)
2089 to
= (struct bpf_tunnel_key
*)compat
;
2096 to
->tunnel_id
= be64_to_cpu(info
->key
.tun_id
);
2097 to
->tunnel_tos
= info
->key
.tos
;
2098 to
->tunnel_ttl
= info
->key
.ttl
;
2100 if (flags
& BPF_F_TUNINFO_IPV6
) {
2101 memcpy(to
->remote_ipv6
, &info
->key
.u
.ipv6
.src
,
2102 sizeof(to
->remote_ipv6
));
2103 to
->tunnel_label
= be32_to_cpu(info
->key
.label
);
2105 to
->remote_ipv4
= be32_to_cpu(info
->key
.u
.ipv4
.src
);
2108 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
)))
2109 memcpy(to_orig
, to
, size
);
2113 memset(to_orig
, 0, size
);
2117 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto
= {
2118 .func
= bpf_skb_get_tunnel_key
,
2120 .ret_type
= RET_INTEGER
,
2121 .arg1_type
= ARG_PTR_TO_CTX
,
2122 .arg2_type
= ARG_PTR_TO_RAW_STACK
,
2123 .arg3_type
= ARG_CONST_STACK_SIZE
,
2124 .arg4_type
= ARG_ANYTHING
,
2127 static u64
bpf_skb_get_tunnel_opt(u64 r1
, u64 r2
, u64 size
, u64 r4
, u64 r5
)
2129 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
2130 u8
*to
= (u8
*) (long) r2
;
2131 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
2134 if (unlikely(!info
||
2135 !(info
->key
.tun_flags
& TUNNEL_OPTIONS_PRESENT
))) {
2139 if (unlikely(size
< info
->options_len
)) {
2144 ip_tunnel_info_opts_get(to
, info
);
2145 if (size
> info
->options_len
)
2146 memset(to
+ info
->options_len
, 0, size
- info
->options_len
);
2148 return info
->options_len
;
2150 memset(to
, 0, size
);
2154 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto
= {
2155 .func
= bpf_skb_get_tunnel_opt
,
2157 .ret_type
= RET_INTEGER
,
2158 .arg1_type
= ARG_PTR_TO_CTX
,
2159 .arg2_type
= ARG_PTR_TO_RAW_STACK
,
2160 .arg3_type
= ARG_CONST_STACK_SIZE
,
2163 static struct metadata_dst __percpu
*md_dst
;
2165 static u64
bpf_skb_set_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
2167 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
2168 struct bpf_tunnel_key
*from
= (struct bpf_tunnel_key
*) (long) r2
;
2169 struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
2170 u8 compat
[sizeof(struct bpf_tunnel_key
)];
2171 struct ip_tunnel_info
*info
;
2173 if (unlikely(flags
& ~(BPF_F_TUNINFO_IPV6
| BPF_F_ZERO_CSUM_TX
|
2174 BPF_F_DONT_FRAGMENT
)))
2176 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
2178 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
2179 case offsetof(struct bpf_tunnel_key
, tunnel_ext
):
2180 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
2181 /* Fixup deprecated structure layouts here, so we have
2182 * a common path later on.
2184 memcpy(compat
, from
, size
);
2185 memset(compat
+ size
, 0, sizeof(compat
) - size
);
2186 from
= (struct bpf_tunnel_key
*)compat
;
2192 if (unlikely((!(flags
& BPF_F_TUNINFO_IPV6
) && from
->tunnel_label
) ||
2197 dst_hold((struct dst_entry
*) md
);
2198 skb_dst_set(skb
, (struct dst_entry
*) md
);
2200 info
= &md
->u
.tun_info
;
2201 info
->mode
= IP_TUNNEL_INFO_TX
;
2203 info
->key
.tun_flags
= TUNNEL_KEY
| TUNNEL_CSUM
| TUNNEL_NOCACHE
;
2204 if (flags
& BPF_F_DONT_FRAGMENT
)
2205 info
->key
.tun_flags
|= TUNNEL_DONT_FRAGMENT
;
2207 info
->key
.tun_id
= cpu_to_be64(from
->tunnel_id
);
2208 info
->key
.tos
= from
->tunnel_tos
;
2209 info
->key
.ttl
= from
->tunnel_ttl
;
2211 if (flags
& BPF_F_TUNINFO_IPV6
) {
2212 info
->mode
|= IP_TUNNEL_INFO_IPV6
;
2213 memcpy(&info
->key
.u
.ipv6
.dst
, from
->remote_ipv6
,
2214 sizeof(from
->remote_ipv6
));
2215 info
->key
.label
= cpu_to_be32(from
->tunnel_label
) &
2216 IPV6_FLOWLABEL_MASK
;
2218 info
->key
.u
.ipv4
.dst
= cpu_to_be32(from
->remote_ipv4
);
2219 if (flags
& BPF_F_ZERO_CSUM_TX
)
2220 info
->key
.tun_flags
&= ~TUNNEL_CSUM
;
2226 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto
= {
2227 .func
= bpf_skb_set_tunnel_key
,
2229 .ret_type
= RET_INTEGER
,
2230 .arg1_type
= ARG_PTR_TO_CTX
,
2231 .arg2_type
= ARG_PTR_TO_STACK
,
2232 .arg3_type
= ARG_CONST_STACK_SIZE
,
2233 .arg4_type
= ARG_ANYTHING
,
2236 static u64
bpf_skb_set_tunnel_opt(u64 r1
, u64 r2
, u64 size
, u64 r4
, u64 r5
)
2238 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
2239 u8
*from
= (u8
*) (long) r2
;
2240 struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
2241 const struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
2243 if (unlikely(info
!= &md
->u
.tun_info
|| (size
& (sizeof(u32
) - 1))))
2245 if (unlikely(size
> IP_TUNNEL_OPTS_MAX
))
2248 ip_tunnel_info_opts_set(info
, from
, size
);
2253 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto
= {
2254 .func
= bpf_skb_set_tunnel_opt
,
2256 .ret_type
= RET_INTEGER
,
2257 .arg1_type
= ARG_PTR_TO_CTX
,
2258 .arg2_type
= ARG_PTR_TO_STACK
,
2259 .arg3_type
= ARG_CONST_STACK_SIZE
,
2262 static const struct bpf_func_proto
*
2263 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which
)
2266 /* Race is not possible, since it's called from verifier
2267 * that is holding verifier mutex.
2269 md_dst
= metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX
,
2276 case BPF_FUNC_skb_set_tunnel_key
:
2277 return &bpf_skb_set_tunnel_key_proto
;
2278 case BPF_FUNC_skb_set_tunnel_opt
:
2279 return &bpf_skb_set_tunnel_opt_proto
;
2285 #ifdef CONFIG_SOCK_CGROUP_DATA
2286 static u64
bpf_skb_under_cgroup(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
2288 struct sk_buff
*skb
= (struct sk_buff
*)(long)r1
;
2289 struct bpf_map
*map
= (struct bpf_map
*)(long)r2
;
2290 struct bpf_array
*array
= container_of(map
, struct bpf_array
, map
);
2291 struct cgroup
*cgrp
;
2296 if (!sk
|| !sk_fullsock(sk
))
2299 if (unlikely(i
>= array
->map
.max_entries
))
2302 cgrp
= READ_ONCE(array
->ptrs
[i
]);
2303 if (unlikely(!cgrp
))
2306 return cgroup_is_descendant(sock_cgroup_ptr(&sk
->sk_cgrp_data
), cgrp
);
2309 static const struct bpf_func_proto bpf_skb_under_cgroup_proto
= {
2310 .func
= bpf_skb_under_cgroup
,
2312 .ret_type
= RET_INTEGER
,
2313 .arg1_type
= ARG_PTR_TO_CTX
,
2314 .arg2_type
= ARG_CONST_MAP_PTR
,
2315 .arg3_type
= ARG_ANYTHING
,
2319 static const struct bpf_func_proto
*
2320 sk_filter_func_proto(enum bpf_func_id func_id
)
2323 case BPF_FUNC_map_lookup_elem
:
2324 return &bpf_map_lookup_elem_proto
;
2325 case BPF_FUNC_map_update_elem
:
2326 return &bpf_map_update_elem_proto
;
2327 case BPF_FUNC_map_delete_elem
:
2328 return &bpf_map_delete_elem_proto
;
2329 case BPF_FUNC_get_prandom_u32
:
2330 return &bpf_get_prandom_u32_proto
;
2331 case BPF_FUNC_get_smp_processor_id
:
2332 return &bpf_get_raw_smp_processor_id_proto
;
2333 case BPF_FUNC_tail_call
:
2334 return &bpf_tail_call_proto
;
2335 case BPF_FUNC_ktime_get_ns
:
2336 return &bpf_ktime_get_ns_proto
;
2337 case BPF_FUNC_trace_printk
:
2338 if (capable(CAP_SYS_ADMIN
))
2339 return bpf_get_trace_printk_proto();
2345 static const struct bpf_func_proto
*
2346 tc_cls_act_func_proto(enum bpf_func_id func_id
)
2349 case BPF_FUNC_skb_store_bytes
:
2350 return &bpf_skb_store_bytes_proto
;
2351 case BPF_FUNC_skb_load_bytes
:
2352 return &bpf_skb_load_bytes_proto
;
2353 case BPF_FUNC_csum_diff
:
2354 return &bpf_csum_diff_proto
;
2355 case BPF_FUNC_l3_csum_replace
:
2356 return &bpf_l3_csum_replace_proto
;
2357 case BPF_FUNC_l4_csum_replace
:
2358 return &bpf_l4_csum_replace_proto
;
2359 case BPF_FUNC_clone_redirect
:
2360 return &bpf_clone_redirect_proto
;
2361 case BPF_FUNC_get_cgroup_classid
:
2362 return &bpf_get_cgroup_classid_proto
;
2363 case BPF_FUNC_skb_vlan_push
:
2364 return &bpf_skb_vlan_push_proto
;
2365 case BPF_FUNC_skb_vlan_pop
:
2366 return &bpf_skb_vlan_pop_proto
;
2367 case BPF_FUNC_skb_change_proto
:
2368 return &bpf_skb_change_proto_proto
;
2369 case BPF_FUNC_skb_change_type
:
2370 return &bpf_skb_change_type_proto
;
2371 case BPF_FUNC_skb_get_tunnel_key
:
2372 return &bpf_skb_get_tunnel_key_proto
;
2373 case BPF_FUNC_skb_set_tunnel_key
:
2374 return bpf_get_skb_set_tunnel_proto(func_id
);
2375 case BPF_FUNC_skb_get_tunnel_opt
:
2376 return &bpf_skb_get_tunnel_opt_proto
;
2377 case BPF_FUNC_skb_set_tunnel_opt
:
2378 return bpf_get_skb_set_tunnel_proto(func_id
);
2379 case BPF_FUNC_redirect
:
2380 return &bpf_redirect_proto
;
2381 case BPF_FUNC_get_route_realm
:
2382 return &bpf_get_route_realm_proto
;
2383 case BPF_FUNC_get_hash_recalc
:
2384 return &bpf_get_hash_recalc_proto
;
2385 case BPF_FUNC_perf_event_output
:
2386 return &bpf_skb_event_output_proto
;
2387 case BPF_FUNC_get_smp_processor_id
:
2388 return &bpf_get_smp_processor_id_proto
;
2389 #ifdef CONFIG_SOCK_CGROUP_DATA
2390 case BPF_FUNC_skb_under_cgroup
:
2391 return &bpf_skb_under_cgroup_proto
;
2394 return sk_filter_func_proto(func_id
);
2398 static const struct bpf_func_proto
*
2399 xdp_func_proto(enum bpf_func_id func_id
)
2401 return sk_filter_func_proto(func_id
);
2404 static bool __is_valid_access(int off
, int size
, enum bpf_access_type type
)
2406 if (off
< 0 || off
>= sizeof(struct __sk_buff
))
2408 /* The verifier guarantees that size > 0. */
2409 if (off
% size
!= 0)
2411 if (size
!= sizeof(__u32
))
2417 static bool sk_filter_is_valid_access(int off
, int size
,
2418 enum bpf_access_type type
,
2419 enum bpf_reg_type
*reg_type
)
2422 case offsetof(struct __sk_buff
, tc_classid
):
2423 case offsetof(struct __sk_buff
, data
):
2424 case offsetof(struct __sk_buff
, data_end
):
2428 if (type
== BPF_WRITE
) {
2430 case offsetof(struct __sk_buff
, cb
[0]) ...
2431 offsetof(struct __sk_buff
, cb
[4]):
2438 return __is_valid_access(off
, size
, type
);
2441 static bool tc_cls_act_is_valid_access(int off
, int size
,
2442 enum bpf_access_type type
,
2443 enum bpf_reg_type
*reg_type
)
2445 if (type
== BPF_WRITE
) {
2447 case offsetof(struct __sk_buff
, mark
):
2448 case offsetof(struct __sk_buff
, tc_index
):
2449 case offsetof(struct __sk_buff
, priority
):
2450 case offsetof(struct __sk_buff
, cb
[0]) ...
2451 offsetof(struct __sk_buff
, cb
[4]):
2452 case offsetof(struct __sk_buff
, tc_classid
):
2460 case offsetof(struct __sk_buff
, data
):
2461 *reg_type
= PTR_TO_PACKET
;
2463 case offsetof(struct __sk_buff
, data_end
):
2464 *reg_type
= PTR_TO_PACKET_END
;
2468 return __is_valid_access(off
, size
, type
);
2471 static bool __is_valid_xdp_access(int off
, int size
,
2472 enum bpf_access_type type
)
2474 if (off
< 0 || off
>= sizeof(struct xdp_md
))
2476 if (off
% size
!= 0)
2484 static bool xdp_is_valid_access(int off
, int size
,
2485 enum bpf_access_type type
,
2486 enum bpf_reg_type
*reg_type
)
2488 if (type
== BPF_WRITE
)
2492 case offsetof(struct xdp_md
, data
):
2493 *reg_type
= PTR_TO_PACKET
;
2495 case offsetof(struct xdp_md
, data_end
):
2496 *reg_type
= PTR_TO_PACKET_END
;
2500 return __is_valid_xdp_access(off
, size
, type
);
2503 void bpf_warn_invalid_xdp_action(u32 act
)
2505 WARN_ONCE(1, "Illegal XDP return value %u, expect packet loss\n", act
);
2507 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action
);
2509 static u32
bpf_net_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2510 int src_reg
, int ctx_off
,
2511 struct bpf_insn
*insn_buf
,
2512 struct bpf_prog
*prog
)
2514 struct bpf_insn
*insn
= insn_buf
;
2517 case offsetof(struct __sk_buff
, len
):
2518 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, len
) != 4);
2520 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2521 offsetof(struct sk_buff
, len
));
2524 case offsetof(struct __sk_buff
, protocol
):
2525 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
2527 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2528 offsetof(struct sk_buff
, protocol
));
2531 case offsetof(struct __sk_buff
, vlan_proto
):
2532 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
2534 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2535 offsetof(struct sk_buff
, vlan_proto
));
2538 case offsetof(struct __sk_buff
, priority
):
2539 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, priority
) != 4);
2541 if (type
== BPF_WRITE
)
2542 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2543 offsetof(struct sk_buff
, priority
));
2545 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2546 offsetof(struct sk_buff
, priority
));
2549 case offsetof(struct __sk_buff
, ingress_ifindex
):
2550 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, skb_iif
) != 4);
2552 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2553 offsetof(struct sk_buff
, skb_iif
));
2556 case offsetof(struct __sk_buff
, ifindex
):
2557 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
2559 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
2561 offsetof(struct sk_buff
, dev
));
2562 *insn
++ = BPF_JMP_IMM(BPF_JEQ
, dst_reg
, 0, 1);
2563 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, dst_reg
,
2564 offsetof(struct net_device
, ifindex
));
2567 case offsetof(struct __sk_buff
, hash
):
2568 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
2570 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2571 offsetof(struct sk_buff
, hash
));
2574 case offsetof(struct __sk_buff
, mark
):
2575 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
2577 if (type
== BPF_WRITE
)
2578 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2579 offsetof(struct sk_buff
, mark
));
2581 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2582 offsetof(struct sk_buff
, mark
));
2585 case offsetof(struct __sk_buff
, pkt_type
):
2586 return convert_skb_access(SKF_AD_PKTTYPE
, dst_reg
, src_reg
, insn
);
2588 case offsetof(struct __sk_buff
, queue_mapping
):
2589 return convert_skb_access(SKF_AD_QUEUE
, dst_reg
, src_reg
, insn
);
2591 case offsetof(struct __sk_buff
, vlan_present
):
2592 return convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
2593 dst_reg
, src_reg
, insn
);
2595 case offsetof(struct __sk_buff
, vlan_tci
):
2596 return convert_skb_access(SKF_AD_VLAN_TAG
,
2597 dst_reg
, src_reg
, insn
);
2599 case offsetof(struct __sk_buff
, cb
[0]) ...
2600 offsetof(struct __sk_buff
, cb
[4]):
2601 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb
, data
) < 20);
2603 prog
->cb_access
= 1;
2604 ctx_off
-= offsetof(struct __sk_buff
, cb
[0]);
2605 ctx_off
+= offsetof(struct sk_buff
, cb
);
2606 ctx_off
+= offsetof(struct qdisc_skb_cb
, data
);
2607 if (type
== BPF_WRITE
)
2608 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2610 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2613 case offsetof(struct __sk_buff
, tc_classid
):
2614 ctx_off
-= offsetof(struct __sk_buff
, tc_classid
);
2615 ctx_off
+= offsetof(struct sk_buff
, cb
);
2616 ctx_off
+= offsetof(struct qdisc_skb_cb
, tc_classid
);
2617 if (type
== BPF_WRITE
)
2618 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2620 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2623 case offsetof(struct __sk_buff
, data
):
2624 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, data
)),
2626 offsetof(struct sk_buff
, data
));
2629 case offsetof(struct __sk_buff
, data_end
):
2630 ctx_off
-= offsetof(struct __sk_buff
, data_end
);
2631 ctx_off
+= offsetof(struct sk_buff
, cb
);
2632 ctx_off
+= offsetof(struct bpf_skb_data_end
, data_end
);
2633 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(sizeof(void *)),
2634 dst_reg
, src_reg
, ctx_off
);
2637 case offsetof(struct __sk_buff
, tc_index
):
2638 #ifdef CONFIG_NET_SCHED
2639 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, tc_index
) != 2);
2641 if (type
== BPF_WRITE
)
2642 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
,
2643 offsetof(struct sk_buff
, tc_index
));
2645 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2646 offsetof(struct sk_buff
, tc_index
));
2649 if (type
== BPF_WRITE
)
2650 *insn
++ = BPF_MOV64_REG(dst_reg
, dst_reg
);
2652 *insn
++ = BPF_MOV64_IMM(dst_reg
, 0);
2657 return insn
- insn_buf
;
2660 static u32
xdp_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2661 int src_reg
, int ctx_off
,
2662 struct bpf_insn
*insn_buf
,
2663 struct bpf_prog
*prog
)
2665 struct bpf_insn
*insn
= insn_buf
;
2668 case offsetof(struct xdp_md
, data
):
2669 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct xdp_buff
, data
)),
2671 offsetof(struct xdp_buff
, data
));
2673 case offsetof(struct xdp_md
, data_end
):
2674 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct xdp_buff
, data_end
)),
2676 offsetof(struct xdp_buff
, data_end
));
2680 return insn
- insn_buf
;
2683 static const struct bpf_verifier_ops sk_filter_ops
= {
2684 .get_func_proto
= sk_filter_func_proto
,
2685 .is_valid_access
= sk_filter_is_valid_access
,
2686 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2689 static const struct bpf_verifier_ops tc_cls_act_ops
= {
2690 .get_func_proto
= tc_cls_act_func_proto
,
2691 .is_valid_access
= tc_cls_act_is_valid_access
,
2692 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2695 static const struct bpf_verifier_ops xdp_ops
= {
2696 .get_func_proto
= xdp_func_proto
,
2697 .is_valid_access
= xdp_is_valid_access
,
2698 .convert_ctx_access
= xdp_convert_ctx_access
,
2701 static struct bpf_prog_type_list sk_filter_type __read_mostly
= {
2702 .ops
= &sk_filter_ops
,
2703 .type
= BPF_PROG_TYPE_SOCKET_FILTER
,
2706 static struct bpf_prog_type_list sched_cls_type __read_mostly
= {
2707 .ops
= &tc_cls_act_ops
,
2708 .type
= BPF_PROG_TYPE_SCHED_CLS
,
2711 static struct bpf_prog_type_list sched_act_type __read_mostly
= {
2712 .ops
= &tc_cls_act_ops
,
2713 .type
= BPF_PROG_TYPE_SCHED_ACT
,
2716 static struct bpf_prog_type_list xdp_type __read_mostly
= {
2718 .type
= BPF_PROG_TYPE_XDP
,
2721 static int __init
register_sk_filter_ops(void)
2723 bpf_register_prog_type(&sk_filter_type
);
2724 bpf_register_prog_type(&sched_cls_type
);
2725 bpf_register_prog_type(&sched_act_type
);
2726 bpf_register_prog_type(&xdp_type
);
2730 late_initcall(register_sk_filter_ops
);
2732 int sk_detach_filter(struct sock
*sk
)
2735 struct sk_filter
*filter
;
2737 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
2740 filter
= rcu_dereference_protected(sk
->sk_filter
,
2741 lockdep_sock_is_held(sk
));
2743 RCU_INIT_POINTER(sk
->sk_filter
, NULL
);
2744 sk_filter_uncharge(sk
, filter
);
2750 EXPORT_SYMBOL_GPL(sk_detach_filter
);
2752 int sk_get_filter(struct sock
*sk
, struct sock_filter __user
*ubuf
,
2755 struct sock_fprog_kern
*fprog
;
2756 struct sk_filter
*filter
;
2760 filter
= rcu_dereference_protected(sk
->sk_filter
,
2761 lockdep_sock_is_held(sk
));
2765 /* We're copying the filter that has been originally attached,
2766 * so no conversion/decode needed anymore. eBPF programs that
2767 * have no original program cannot be dumped through this.
2770 fprog
= filter
->prog
->orig_prog
;
2776 /* User space only enquires number of filter blocks. */
2780 if (len
< fprog
->len
)
2784 if (copy_to_user(ubuf
, fprog
->filter
, bpf_classic_proglen(fprog
)))
2787 /* Instead of bytes, the API requests to return the number