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 - run a packet through a socket filter
57 * @sk: sock associated with &sk_buff
58 * @skb: buffer to filter
60 * Run the eBPF program and then cut skb->data to correct size returned by
61 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
62 * than pkt_len we keep whole skb->data. This is the socket level
63 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
64 * be accepted or -EPERM if the packet should be tossed.
67 int sk_filter(struct sock
*sk
, struct sk_buff
*skb
)
70 struct sk_filter
*filter
;
73 * If the skb was allocated from pfmemalloc reserves, only
74 * allow SOCK_MEMALLOC sockets to use it as this socket is
77 if (skb_pfmemalloc(skb
) && !sock_flag(sk
, SOCK_MEMALLOC
))
80 err
= security_sock_rcv_skb(sk
, skb
);
85 filter
= rcu_dereference(sk
->sk_filter
);
87 unsigned int pkt_len
= bpf_prog_run_save_cb(filter
->prog
, skb
);
89 err
= pkt_len
? pskb_trim(skb
, pkt_len
) : -EPERM
;
95 EXPORT_SYMBOL(sk_filter
);
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 u32
convert_skb_access(int skb_field
, int dst_reg
, int src_reg
,
154 struct bpf_insn
*insn_buf
)
156 struct bpf_insn
*insn
= insn_buf
;
160 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
162 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
163 offsetof(struct sk_buff
, mark
));
167 *insn
++ = BPF_LDX_MEM(BPF_B
, dst_reg
, src_reg
, PKT_TYPE_OFFSET());
168 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, PKT_TYPE_MAX
);
169 #ifdef __BIG_ENDIAN_BITFIELD
170 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 5);
175 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, queue_mapping
) != 2);
177 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
178 offsetof(struct sk_buff
, queue_mapping
));
181 case SKF_AD_VLAN_TAG
:
182 case SKF_AD_VLAN_TAG_PRESENT
:
183 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_tci
) != 2);
184 BUILD_BUG_ON(VLAN_TAG_PRESENT
!= 0x1000);
186 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
187 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
188 offsetof(struct sk_buff
, vlan_tci
));
189 if (skb_field
== SKF_AD_VLAN_TAG
) {
190 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
,
194 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 12);
196 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, 1);
201 return insn
- insn_buf
;
204 static bool convert_bpf_extensions(struct sock_filter
*fp
,
205 struct bpf_insn
**insnp
)
207 struct bpf_insn
*insn
= *insnp
;
211 case SKF_AD_OFF
+ SKF_AD_PROTOCOL
:
212 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
214 /* A = *(u16 *) (CTX + offsetof(protocol)) */
215 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
216 offsetof(struct sk_buff
, protocol
));
217 /* A = ntohs(A) [emitting a nop or swap16] */
218 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
221 case SKF_AD_OFF
+ SKF_AD_PKTTYPE
:
222 cnt
= convert_skb_access(SKF_AD_PKTTYPE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
226 case SKF_AD_OFF
+ SKF_AD_IFINDEX
:
227 case SKF_AD_OFF
+ SKF_AD_HATYPE
:
228 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
229 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, type
) != 2);
230 BUILD_BUG_ON(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)) < 0);
232 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
233 BPF_REG_TMP
, BPF_REG_CTX
,
234 offsetof(struct sk_buff
, dev
));
235 /* if (tmp != 0) goto pc + 1 */
236 *insn
++ = BPF_JMP_IMM(BPF_JNE
, BPF_REG_TMP
, 0, 1);
237 *insn
++ = BPF_EXIT_INSN();
238 if (fp
->k
== SKF_AD_OFF
+ SKF_AD_IFINDEX
)
239 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_TMP
,
240 offsetof(struct net_device
, ifindex
));
242 *insn
= BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_TMP
,
243 offsetof(struct net_device
, type
));
246 case SKF_AD_OFF
+ SKF_AD_MARK
:
247 cnt
= convert_skb_access(SKF_AD_MARK
, BPF_REG_A
, BPF_REG_CTX
, insn
);
251 case SKF_AD_OFF
+ SKF_AD_RXHASH
:
252 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
254 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
,
255 offsetof(struct sk_buff
, hash
));
258 case SKF_AD_OFF
+ SKF_AD_QUEUE
:
259 cnt
= convert_skb_access(SKF_AD_QUEUE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
263 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG
:
264 cnt
= convert_skb_access(SKF_AD_VLAN_TAG
,
265 BPF_REG_A
, BPF_REG_CTX
, insn
);
269 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
:
270 cnt
= convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
271 BPF_REG_A
, BPF_REG_CTX
, insn
);
275 case SKF_AD_OFF
+ SKF_AD_VLAN_TPID
:
276 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
278 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
279 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
280 offsetof(struct sk_buff
, vlan_proto
));
281 /* A = ntohs(A) [emitting a nop or swap16] */
282 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
285 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
286 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
287 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
288 case SKF_AD_OFF
+ SKF_AD_CPU
:
289 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
291 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG1
, BPF_REG_CTX
);
293 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG2
, BPF_REG_A
);
295 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG3
, BPF_REG_X
);
296 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
298 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
299 *insn
= BPF_EMIT_CALL(__skb_get_pay_offset
);
301 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
302 *insn
= BPF_EMIT_CALL(__skb_get_nlattr
);
304 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
305 *insn
= BPF_EMIT_CALL(__skb_get_nlattr_nest
);
307 case SKF_AD_OFF
+ SKF_AD_CPU
:
308 *insn
= BPF_EMIT_CALL(__get_raw_cpu_id
);
310 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
311 *insn
= BPF_EMIT_CALL(bpf_user_rnd_u32
);
312 bpf_user_rnd_init_once();
317 case SKF_AD_OFF
+ SKF_AD_ALU_XOR_X
:
319 *insn
= BPF_ALU32_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_X
);
323 /* This is just a dummy call to avoid letting the compiler
324 * evict __bpf_call_base() as an optimization. Placed here
325 * where no-one bothers.
327 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
336 * bpf_convert_filter - convert filter program
337 * @prog: the user passed filter program
338 * @len: the length of the user passed filter program
339 * @new_prog: buffer where converted program will be stored
340 * @new_len: pointer to store length of converted program
342 * Remap 'sock_filter' style BPF instruction set to 'sock_filter_ext' style.
343 * Conversion workflow:
345 * 1) First pass for calculating the new program length:
346 * bpf_convert_filter(old_prog, old_len, NULL, &new_len)
348 * 2) 2nd pass to remap in two passes: 1st pass finds new
349 * jump offsets, 2nd pass remapping:
350 * new_prog = kmalloc(sizeof(struct bpf_insn) * new_len);
351 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
353 static int bpf_convert_filter(struct sock_filter
*prog
, int len
,
354 struct bpf_insn
*new_prog
, int *new_len
)
356 int new_flen
= 0, pass
= 0, target
, i
;
357 struct bpf_insn
*new_insn
;
358 struct sock_filter
*fp
;
362 BUILD_BUG_ON(BPF_MEMWORDS
* sizeof(u32
) > MAX_BPF_STACK
);
363 BUILD_BUG_ON(BPF_REG_FP
+ 1 != MAX_BPF_REG
);
365 if (len
<= 0 || len
> BPF_MAXINSNS
)
369 addrs
= kcalloc(len
, sizeof(*addrs
),
370 GFP_KERNEL
| __GFP_NOWARN
);
379 /* Classic BPF related prologue emission. */
381 /* Classic BPF expects A and X to be reset first. These need
382 * to be guaranteed to be the first two instructions.
384 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_A
);
385 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_X
, BPF_REG_X
);
387 /* All programs must keep CTX in callee saved BPF_REG_CTX.
388 * In eBPF case it's done by the compiler, here we need to
389 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
391 *new_insn
++ = BPF_MOV64_REG(BPF_REG_CTX
, BPF_REG_ARG1
);
396 for (i
= 0; i
< len
; fp
++, i
++) {
397 struct bpf_insn tmp_insns
[6] = { };
398 struct bpf_insn
*insn
= tmp_insns
;
401 addrs
[i
] = new_insn
- new_prog
;
404 /* All arithmetic insns and skb loads map as-is. */
405 case BPF_ALU
| BPF_ADD
| BPF_X
:
406 case BPF_ALU
| BPF_ADD
| BPF_K
:
407 case BPF_ALU
| BPF_SUB
| BPF_X
:
408 case BPF_ALU
| BPF_SUB
| BPF_K
:
409 case BPF_ALU
| BPF_AND
| BPF_X
:
410 case BPF_ALU
| BPF_AND
| BPF_K
:
411 case BPF_ALU
| BPF_OR
| BPF_X
:
412 case BPF_ALU
| BPF_OR
| BPF_K
:
413 case BPF_ALU
| BPF_LSH
| BPF_X
:
414 case BPF_ALU
| BPF_LSH
| BPF_K
:
415 case BPF_ALU
| BPF_RSH
| BPF_X
:
416 case BPF_ALU
| BPF_RSH
| BPF_K
:
417 case BPF_ALU
| BPF_XOR
| BPF_X
:
418 case BPF_ALU
| BPF_XOR
| BPF_K
:
419 case BPF_ALU
| BPF_MUL
| BPF_X
:
420 case BPF_ALU
| BPF_MUL
| BPF_K
:
421 case BPF_ALU
| BPF_DIV
| BPF_X
:
422 case BPF_ALU
| BPF_DIV
| BPF_K
:
423 case BPF_ALU
| BPF_MOD
| BPF_X
:
424 case BPF_ALU
| BPF_MOD
| BPF_K
:
425 case BPF_ALU
| BPF_NEG
:
426 case BPF_LD
| BPF_ABS
| BPF_W
:
427 case BPF_LD
| BPF_ABS
| BPF_H
:
428 case BPF_LD
| BPF_ABS
| BPF_B
:
429 case BPF_LD
| BPF_IND
| BPF_W
:
430 case BPF_LD
| BPF_IND
| BPF_H
:
431 case BPF_LD
| BPF_IND
| BPF_B
:
432 /* Check for overloaded BPF extension and
433 * directly convert it if found, otherwise
434 * just move on with mapping.
436 if (BPF_CLASS(fp
->code
) == BPF_LD
&&
437 BPF_MODE(fp
->code
) == BPF_ABS
&&
438 convert_bpf_extensions(fp
, &insn
))
441 *insn
= BPF_RAW_INSN(fp
->code
, BPF_REG_A
, BPF_REG_X
, 0, fp
->k
);
444 /* Jump transformation cannot use BPF block macros
445 * everywhere as offset calculation and target updates
446 * require a bit more work than the rest, i.e. jump
447 * opcodes map as-is, but offsets need adjustment.
450 #define BPF_EMIT_JMP \
452 if (target >= len || target < 0) \
454 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
455 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
456 insn->off -= insn - tmp_insns; \
459 case BPF_JMP
| BPF_JA
:
460 target
= i
+ fp
->k
+ 1;
461 insn
->code
= fp
->code
;
465 case BPF_JMP
| BPF_JEQ
| BPF_K
:
466 case BPF_JMP
| BPF_JEQ
| BPF_X
:
467 case BPF_JMP
| BPF_JSET
| BPF_K
:
468 case BPF_JMP
| BPF_JSET
| BPF_X
:
469 case BPF_JMP
| BPF_JGT
| BPF_K
:
470 case BPF_JMP
| BPF_JGT
| BPF_X
:
471 case BPF_JMP
| BPF_JGE
| BPF_K
:
472 case BPF_JMP
| BPF_JGE
| BPF_X
:
473 if (BPF_SRC(fp
->code
) == BPF_K
&& (int) fp
->k
< 0) {
474 /* BPF immediates are signed, zero extend
475 * immediate into tmp register and use it
478 *insn
++ = BPF_MOV32_IMM(BPF_REG_TMP
, fp
->k
);
480 insn
->dst_reg
= BPF_REG_A
;
481 insn
->src_reg
= BPF_REG_TMP
;
484 insn
->dst_reg
= BPF_REG_A
;
486 bpf_src
= BPF_SRC(fp
->code
);
487 insn
->src_reg
= bpf_src
== BPF_X
? BPF_REG_X
: 0;
490 /* Common case where 'jump_false' is next insn. */
492 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
493 target
= i
+ fp
->jt
+ 1;
498 /* Convert JEQ into JNE when 'jump_true' is next insn. */
499 if (fp
->jt
== 0 && BPF_OP(fp
->code
) == BPF_JEQ
) {
500 insn
->code
= BPF_JMP
| BPF_JNE
| bpf_src
;
501 target
= i
+ fp
->jf
+ 1;
506 /* Other jumps are mapped into two insns: Jxx and JA. */
507 target
= i
+ fp
->jt
+ 1;
508 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
512 insn
->code
= BPF_JMP
| BPF_JA
;
513 target
= i
+ fp
->jf
+ 1;
517 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
518 case BPF_LDX
| BPF_MSH
| BPF_B
:
520 *insn
++ = BPF_MOV64_REG(BPF_REG_TMP
, BPF_REG_A
);
521 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
522 *insn
++ = BPF_LD_ABS(BPF_B
, fp
->k
);
524 *insn
++ = BPF_ALU32_IMM(BPF_AND
, BPF_REG_A
, 0xf);
526 *insn
++ = BPF_ALU32_IMM(BPF_LSH
, BPF_REG_A
, 2);
528 *insn
++ = BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
530 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_TMP
);
533 /* RET_K, RET_A are remaped into 2 insns. */
534 case BPF_RET
| BPF_A
:
535 case BPF_RET
| BPF_K
:
536 *insn
++ = BPF_MOV32_RAW(BPF_RVAL(fp
->code
) == BPF_K
?
537 BPF_K
: BPF_X
, BPF_REG_0
,
539 *insn
= BPF_EXIT_INSN();
542 /* Store to stack. */
545 *insn
= BPF_STX_MEM(BPF_W
, BPF_REG_FP
, BPF_CLASS(fp
->code
) ==
546 BPF_ST
? BPF_REG_A
: BPF_REG_X
,
547 -(BPF_MEMWORDS
- fp
->k
) * 4);
550 /* Load from stack. */
551 case BPF_LD
| BPF_MEM
:
552 case BPF_LDX
| BPF_MEM
:
553 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
554 BPF_REG_A
: BPF_REG_X
, BPF_REG_FP
,
555 -(BPF_MEMWORDS
- fp
->k
) * 4);
559 case BPF_LD
| BPF_IMM
:
560 case BPF_LDX
| BPF_IMM
:
561 *insn
= BPF_MOV32_IMM(BPF_CLASS(fp
->code
) == BPF_LD
?
562 BPF_REG_A
: BPF_REG_X
, fp
->k
);
566 case BPF_MISC
| BPF_TAX
:
567 *insn
= BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
571 case BPF_MISC
| BPF_TXA
:
572 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_X
);
575 /* A = skb->len or X = skb->len */
576 case BPF_LD
| BPF_W
| BPF_LEN
:
577 case BPF_LDX
| BPF_W
| BPF_LEN
:
578 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
579 BPF_REG_A
: BPF_REG_X
, BPF_REG_CTX
,
580 offsetof(struct sk_buff
, len
));
583 /* Access seccomp_data fields. */
584 case BPF_LDX
| BPF_ABS
| BPF_W
:
585 /* A = *(u32 *) (ctx + K) */
586 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
, fp
->k
);
589 /* Unknown instruction. */
596 memcpy(new_insn
, tmp_insns
,
597 sizeof(*insn
) * (insn
- tmp_insns
));
598 new_insn
+= insn
- tmp_insns
;
602 /* Only calculating new length. */
603 *new_len
= new_insn
- new_prog
;
608 if (new_flen
!= new_insn
- new_prog
) {
609 new_flen
= new_insn
- new_prog
;
616 BUG_ON(*new_len
!= new_flen
);
625 * As we dont want to clear mem[] array for each packet going through
626 * __bpf_prog_run(), we check that filter loaded by user never try to read
627 * a cell if not previously written, and we check all branches to be sure
628 * a malicious user doesn't try to abuse us.
630 static int check_load_and_stores(const struct sock_filter
*filter
, int flen
)
632 u16
*masks
, memvalid
= 0; /* One bit per cell, 16 cells */
635 BUILD_BUG_ON(BPF_MEMWORDS
> 16);
637 masks
= kmalloc_array(flen
, sizeof(*masks
), GFP_KERNEL
);
641 memset(masks
, 0xff, flen
* sizeof(*masks
));
643 for (pc
= 0; pc
< flen
; pc
++) {
644 memvalid
&= masks
[pc
];
646 switch (filter
[pc
].code
) {
649 memvalid
|= (1 << filter
[pc
].k
);
651 case BPF_LD
| BPF_MEM
:
652 case BPF_LDX
| BPF_MEM
:
653 if (!(memvalid
& (1 << filter
[pc
].k
))) {
658 case BPF_JMP
| BPF_JA
:
659 /* A jump must set masks on target */
660 masks
[pc
+ 1 + filter
[pc
].k
] &= memvalid
;
663 case BPF_JMP
| BPF_JEQ
| BPF_K
:
664 case BPF_JMP
| BPF_JEQ
| BPF_X
:
665 case BPF_JMP
| BPF_JGE
| BPF_K
:
666 case BPF_JMP
| BPF_JGE
| BPF_X
:
667 case BPF_JMP
| BPF_JGT
| BPF_K
:
668 case BPF_JMP
| BPF_JGT
| BPF_X
:
669 case BPF_JMP
| BPF_JSET
| BPF_K
:
670 case BPF_JMP
| BPF_JSET
| BPF_X
:
671 /* A jump must set masks on targets */
672 masks
[pc
+ 1 + filter
[pc
].jt
] &= memvalid
;
673 masks
[pc
+ 1 + filter
[pc
].jf
] &= memvalid
;
683 static bool chk_code_allowed(u16 code_to_probe
)
685 static const bool codes
[] = {
686 /* 32 bit ALU operations */
687 [BPF_ALU
| BPF_ADD
| BPF_K
] = true,
688 [BPF_ALU
| BPF_ADD
| BPF_X
] = true,
689 [BPF_ALU
| BPF_SUB
| BPF_K
] = true,
690 [BPF_ALU
| BPF_SUB
| BPF_X
] = true,
691 [BPF_ALU
| BPF_MUL
| BPF_K
] = true,
692 [BPF_ALU
| BPF_MUL
| BPF_X
] = true,
693 [BPF_ALU
| BPF_DIV
| BPF_K
] = true,
694 [BPF_ALU
| BPF_DIV
| BPF_X
] = true,
695 [BPF_ALU
| BPF_MOD
| BPF_K
] = true,
696 [BPF_ALU
| BPF_MOD
| BPF_X
] = true,
697 [BPF_ALU
| BPF_AND
| BPF_K
] = true,
698 [BPF_ALU
| BPF_AND
| BPF_X
] = true,
699 [BPF_ALU
| BPF_OR
| BPF_K
] = true,
700 [BPF_ALU
| BPF_OR
| BPF_X
] = true,
701 [BPF_ALU
| BPF_XOR
| BPF_K
] = true,
702 [BPF_ALU
| BPF_XOR
| BPF_X
] = true,
703 [BPF_ALU
| BPF_LSH
| BPF_K
] = true,
704 [BPF_ALU
| BPF_LSH
| BPF_X
] = true,
705 [BPF_ALU
| BPF_RSH
| BPF_K
] = true,
706 [BPF_ALU
| BPF_RSH
| BPF_X
] = true,
707 [BPF_ALU
| BPF_NEG
] = true,
708 /* Load instructions */
709 [BPF_LD
| BPF_W
| BPF_ABS
] = true,
710 [BPF_LD
| BPF_H
| BPF_ABS
] = true,
711 [BPF_LD
| BPF_B
| BPF_ABS
] = true,
712 [BPF_LD
| BPF_W
| BPF_LEN
] = true,
713 [BPF_LD
| BPF_W
| BPF_IND
] = true,
714 [BPF_LD
| BPF_H
| BPF_IND
] = true,
715 [BPF_LD
| BPF_B
| BPF_IND
] = true,
716 [BPF_LD
| BPF_IMM
] = true,
717 [BPF_LD
| BPF_MEM
] = true,
718 [BPF_LDX
| BPF_W
| BPF_LEN
] = true,
719 [BPF_LDX
| BPF_B
| BPF_MSH
] = true,
720 [BPF_LDX
| BPF_IMM
] = true,
721 [BPF_LDX
| BPF_MEM
] = true,
722 /* Store instructions */
725 /* Misc instructions */
726 [BPF_MISC
| BPF_TAX
] = true,
727 [BPF_MISC
| BPF_TXA
] = true,
728 /* Return instructions */
729 [BPF_RET
| BPF_K
] = true,
730 [BPF_RET
| BPF_A
] = true,
731 /* Jump instructions */
732 [BPF_JMP
| BPF_JA
] = true,
733 [BPF_JMP
| BPF_JEQ
| BPF_K
] = true,
734 [BPF_JMP
| BPF_JEQ
| BPF_X
] = true,
735 [BPF_JMP
| BPF_JGE
| BPF_K
] = true,
736 [BPF_JMP
| BPF_JGE
| BPF_X
] = true,
737 [BPF_JMP
| BPF_JGT
| BPF_K
] = true,
738 [BPF_JMP
| BPF_JGT
| BPF_X
] = true,
739 [BPF_JMP
| BPF_JSET
| BPF_K
] = true,
740 [BPF_JMP
| BPF_JSET
| BPF_X
] = true,
743 if (code_to_probe
>= ARRAY_SIZE(codes
))
746 return codes
[code_to_probe
];
750 * bpf_check_classic - verify socket filter code
751 * @filter: filter to verify
752 * @flen: length of filter
754 * Check the user's filter code. If we let some ugly
755 * filter code slip through kaboom! The filter must contain
756 * no references or jumps that are out of range, no illegal
757 * instructions, and must end with a RET instruction.
759 * All jumps are forward as they are not signed.
761 * Returns 0 if the rule set is legal or -EINVAL if not.
763 static int bpf_check_classic(const struct sock_filter
*filter
,
769 if (flen
== 0 || flen
> BPF_MAXINSNS
)
772 /* Check the filter code now */
773 for (pc
= 0; pc
< flen
; pc
++) {
774 const struct sock_filter
*ftest
= &filter
[pc
];
776 /* May we actually operate on this code? */
777 if (!chk_code_allowed(ftest
->code
))
780 /* Some instructions need special checks */
781 switch (ftest
->code
) {
782 case BPF_ALU
| BPF_DIV
| BPF_K
:
783 case BPF_ALU
| BPF_MOD
| BPF_K
:
784 /* Check for division by zero */
788 case BPF_ALU
| BPF_LSH
| BPF_K
:
789 case BPF_ALU
| BPF_RSH
| BPF_K
:
793 case BPF_LD
| BPF_MEM
:
794 case BPF_LDX
| BPF_MEM
:
797 /* Check for invalid memory addresses */
798 if (ftest
->k
>= BPF_MEMWORDS
)
801 case BPF_JMP
| BPF_JA
:
802 /* Note, the large ftest->k might cause loops.
803 * Compare this with conditional jumps below,
804 * where offsets are limited. --ANK (981016)
806 if (ftest
->k
>= (unsigned int)(flen
- pc
- 1))
809 case BPF_JMP
| BPF_JEQ
| BPF_K
:
810 case BPF_JMP
| BPF_JEQ
| BPF_X
:
811 case BPF_JMP
| BPF_JGE
| BPF_K
:
812 case BPF_JMP
| BPF_JGE
| BPF_X
:
813 case BPF_JMP
| BPF_JGT
| BPF_K
:
814 case BPF_JMP
| BPF_JGT
| BPF_X
:
815 case BPF_JMP
| BPF_JSET
| BPF_K
:
816 case BPF_JMP
| BPF_JSET
| BPF_X
:
817 /* Both conditionals must be safe */
818 if (pc
+ ftest
->jt
+ 1 >= flen
||
819 pc
+ ftest
->jf
+ 1 >= flen
)
822 case BPF_LD
| BPF_W
| BPF_ABS
:
823 case BPF_LD
| BPF_H
| BPF_ABS
:
824 case BPF_LD
| BPF_B
| BPF_ABS
:
826 if (bpf_anc_helper(ftest
) & BPF_ANC
)
828 /* Ancillary operation unknown or unsupported */
829 if (anc_found
== false && ftest
->k
>= SKF_AD_OFF
)
834 /* Last instruction must be a RET code */
835 switch (filter
[flen
- 1].code
) {
836 case BPF_RET
| BPF_K
:
837 case BPF_RET
| BPF_A
:
838 return check_load_and_stores(filter
, flen
);
844 static int bpf_prog_store_orig_filter(struct bpf_prog
*fp
,
845 const struct sock_fprog
*fprog
)
847 unsigned int fsize
= bpf_classic_proglen(fprog
);
848 struct sock_fprog_kern
*fkprog
;
850 fp
->orig_prog
= kmalloc(sizeof(*fkprog
), GFP_KERNEL
);
854 fkprog
= fp
->orig_prog
;
855 fkprog
->len
= fprog
->len
;
857 fkprog
->filter
= kmemdup(fp
->insns
, fsize
,
858 GFP_KERNEL
| __GFP_NOWARN
);
859 if (!fkprog
->filter
) {
860 kfree(fp
->orig_prog
);
867 static void bpf_release_orig_filter(struct bpf_prog
*fp
)
869 struct sock_fprog_kern
*fprog
= fp
->orig_prog
;
872 kfree(fprog
->filter
);
877 static void __bpf_prog_release(struct bpf_prog
*prog
)
879 if (prog
->type
== BPF_PROG_TYPE_SOCKET_FILTER
) {
882 bpf_release_orig_filter(prog
);
887 static void __sk_filter_release(struct sk_filter
*fp
)
889 __bpf_prog_release(fp
->prog
);
894 * sk_filter_release_rcu - Release a socket filter by rcu_head
895 * @rcu: rcu_head that contains the sk_filter to free
897 static void sk_filter_release_rcu(struct rcu_head
*rcu
)
899 struct sk_filter
*fp
= container_of(rcu
, struct sk_filter
, rcu
);
901 __sk_filter_release(fp
);
905 * sk_filter_release - release a socket filter
906 * @fp: filter to remove
908 * Remove a filter from a socket and release its resources.
910 static void sk_filter_release(struct sk_filter
*fp
)
912 if (atomic_dec_and_test(&fp
->refcnt
))
913 call_rcu(&fp
->rcu
, sk_filter_release_rcu
);
916 void sk_filter_uncharge(struct sock
*sk
, struct sk_filter
*fp
)
918 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
920 atomic_sub(filter_size
, &sk
->sk_omem_alloc
);
921 sk_filter_release(fp
);
924 /* try to charge the socket memory if there is space available
925 * return true on success
927 bool sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
929 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
931 /* same check as in sock_kmalloc() */
932 if (filter_size
<= sysctl_optmem_max
&&
933 atomic_read(&sk
->sk_omem_alloc
) + filter_size
< sysctl_optmem_max
) {
934 atomic_inc(&fp
->refcnt
);
935 atomic_add(filter_size
, &sk
->sk_omem_alloc
);
941 static struct bpf_prog
*bpf_migrate_filter(struct bpf_prog
*fp
)
943 struct sock_filter
*old_prog
;
944 struct bpf_prog
*old_fp
;
945 int err
, new_len
, old_len
= fp
->len
;
947 /* We are free to overwrite insns et al right here as it
948 * won't be used at this point in time anymore internally
949 * after the migration to the internal BPF instruction
952 BUILD_BUG_ON(sizeof(struct sock_filter
) !=
953 sizeof(struct bpf_insn
));
955 /* Conversion cannot happen on overlapping memory areas,
956 * so we need to keep the user BPF around until the 2nd
957 * pass. At this time, the user BPF is stored in fp->insns.
959 old_prog
= kmemdup(fp
->insns
, old_len
* sizeof(struct sock_filter
),
960 GFP_KERNEL
| __GFP_NOWARN
);
966 /* 1st pass: calculate the new program length. */
967 err
= bpf_convert_filter(old_prog
, old_len
, NULL
, &new_len
);
971 /* Expand fp for appending the new filter representation. */
973 fp
= bpf_prog_realloc(old_fp
, bpf_prog_size(new_len
), 0);
975 /* The old_fp is still around in case we couldn't
976 * allocate new memory, so uncharge on that one.
985 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
986 err
= bpf_convert_filter(old_prog
, old_len
, fp
->insnsi
, &new_len
);
988 /* 2nd bpf_convert_filter() can fail only if it fails
989 * to allocate memory, remapping must succeed. Note,
990 * that at this time old_fp has already been released
995 bpf_prog_select_runtime(fp
);
1003 __bpf_prog_release(fp
);
1004 return ERR_PTR(err
);
1007 static struct bpf_prog
*bpf_prepare_filter(struct bpf_prog
*fp
,
1008 bpf_aux_classic_check_t trans
)
1012 fp
->bpf_func
= NULL
;
1015 err
= bpf_check_classic(fp
->insns
, fp
->len
);
1017 __bpf_prog_release(fp
);
1018 return ERR_PTR(err
);
1021 /* There might be additional checks and transformations
1022 * needed on classic filters, f.e. in case of seccomp.
1025 err
= trans(fp
->insns
, fp
->len
);
1027 __bpf_prog_release(fp
);
1028 return ERR_PTR(err
);
1032 /* Probe if we can JIT compile the filter and if so, do
1033 * the compilation of the filter.
1035 bpf_jit_compile(fp
);
1037 /* JIT compiler couldn't process this filter, so do the
1038 * internal BPF translation for the optimized interpreter.
1041 fp
= bpf_migrate_filter(fp
);
1047 * bpf_prog_create - create an unattached filter
1048 * @pfp: the unattached filter that is created
1049 * @fprog: the filter program
1051 * Create a filter independent of any socket. We first run some
1052 * sanity checks on it to make sure it does not explode on us later.
1053 * If an error occurs or there is insufficient memory for the filter
1054 * a negative errno code is returned. On success the return is zero.
1056 int bpf_prog_create(struct bpf_prog
**pfp
, struct sock_fprog_kern
*fprog
)
1058 unsigned int fsize
= bpf_classic_proglen(fprog
);
1059 struct bpf_prog
*fp
;
1061 /* Make sure new filter is there and in the right amounts. */
1062 if (fprog
->filter
== NULL
)
1065 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1069 memcpy(fp
->insns
, fprog
->filter
, fsize
);
1071 fp
->len
= fprog
->len
;
1072 /* Since unattached filters are not copied back to user
1073 * space through sk_get_filter(), we do not need to hold
1074 * a copy here, and can spare us the work.
1076 fp
->orig_prog
= NULL
;
1078 /* bpf_prepare_filter() already takes care of freeing
1079 * memory in case something goes wrong.
1081 fp
= bpf_prepare_filter(fp
, NULL
);
1088 EXPORT_SYMBOL_GPL(bpf_prog_create
);
1091 * bpf_prog_create_from_user - create an unattached filter from user buffer
1092 * @pfp: the unattached filter that is created
1093 * @fprog: the filter program
1094 * @trans: post-classic verifier transformation handler
1095 * @save_orig: save classic BPF program
1097 * This function effectively does the same as bpf_prog_create(), only
1098 * that it builds up its insns buffer from user space provided buffer.
1099 * It also allows for passing a bpf_aux_classic_check_t handler.
1101 int bpf_prog_create_from_user(struct bpf_prog
**pfp
, struct sock_fprog
*fprog
,
1102 bpf_aux_classic_check_t trans
, bool save_orig
)
1104 unsigned int fsize
= bpf_classic_proglen(fprog
);
1105 struct bpf_prog
*fp
;
1108 /* Make sure new filter is there and in the right amounts. */
1109 if (fprog
->filter
== NULL
)
1112 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1116 if (copy_from_user(fp
->insns
, fprog
->filter
, fsize
)) {
1117 __bpf_prog_free(fp
);
1121 fp
->len
= fprog
->len
;
1122 fp
->orig_prog
= NULL
;
1125 err
= bpf_prog_store_orig_filter(fp
, fprog
);
1127 __bpf_prog_free(fp
);
1132 /* bpf_prepare_filter() already takes care of freeing
1133 * memory in case something goes wrong.
1135 fp
= bpf_prepare_filter(fp
, trans
);
1142 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user
);
1144 void bpf_prog_destroy(struct bpf_prog
*fp
)
1146 __bpf_prog_release(fp
);
1148 EXPORT_SYMBOL_GPL(bpf_prog_destroy
);
1150 static int __sk_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1152 struct sk_filter
*fp
, *old_fp
;
1154 fp
= kmalloc(sizeof(*fp
), GFP_KERNEL
);
1159 atomic_set(&fp
->refcnt
, 0);
1161 if (!sk_filter_charge(sk
, fp
)) {
1166 old_fp
= rcu_dereference_protected(sk
->sk_filter
,
1167 sock_owned_by_user(sk
));
1168 rcu_assign_pointer(sk
->sk_filter
, fp
);
1171 sk_filter_uncharge(sk
, old_fp
);
1176 static int __reuseport_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1178 struct bpf_prog
*old_prog
;
1181 if (bpf_prog_size(prog
->len
) > sysctl_optmem_max
)
1184 if (sk_unhashed(sk
)) {
1185 err
= reuseport_alloc(sk
);
1188 } else if (!rcu_access_pointer(sk
->sk_reuseport_cb
)) {
1189 /* The socket wasn't bound with SO_REUSEPORT */
1193 old_prog
= reuseport_attach_prog(sk
, prog
);
1195 bpf_prog_destroy(old_prog
);
1201 struct bpf_prog
*__get_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1203 unsigned int fsize
= bpf_classic_proglen(fprog
);
1204 unsigned int bpf_fsize
= bpf_prog_size(fprog
->len
);
1205 struct bpf_prog
*prog
;
1208 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1209 return ERR_PTR(-EPERM
);
1211 /* Make sure new filter is there and in the right amounts. */
1212 if (fprog
->filter
== NULL
)
1213 return ERR_PTR(-EINVAL
);
1215 prog
= bpf_prog_alloc(bpf_fsize
, 0);
1217 return ERR_PTR(-ENOMEM
);
1219 if (copy_from_user(prog
->insns
, fprog
->filter
, fsize
)) {
1220 __bpf_prog_free(prog
);
1221 return ERR_PTR(-EFAULT
);
1224 prog
->len
= fprog
->len
;
1226 err
= bpf_prog_store_orig_filter(prog
, fprog
);
1228 __bpf_prog_free(prog
);
1229 return ERR_PTR(-ENOMEM
);
1232 /* bpf_prepare_filter() already takes care of freeing
1233 * memory in case something goes wrong.
1235 return bpf_prepare_filter(prog
, NULL
);
1239 * sk_attach_filter - attach a socket filter
1240 * @fprog: the filter program
1241 * @sk: the socket to use
1243 * Attach the user's filter code. We first run some sanity checks on
1244 * it to make sure it does not explode on us later. If an error
1245 * occurs or there is insufficient memory for the filter a negative
1246 * errno code is returned. On success the return is zero.
1248 int sk_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1250 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1254 return PTR_ERR(prog
);
1256 err
= __sk_attach_prog(prog
, sk
);
1258 __bpf_prog_release(prog
);
1264 EXPORT_SYMBOL_GPL(sk_attach_filter
);
1266 int sk_reuseport_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1268 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1272 return PTR_ERR(prog
);
1274 err
= __reuseport_attach_prog(prog
, sk
);
1276 __bpf_prog_release(prog
);
1283 static struct bpf_prog
*__get_bpf(u32 ufd
, struct sock
*sk
)
1285 struct bpf_prog
*prog
;
1287 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1288 return ERR_PTR(-EPERM
);
1290 prog
= bpf_prog_get(ufd
);
1294 if (prog
->type
!= BPF_PROG_TYPE_SOCKET_FILTER
) {
1296 return ERR_PTR(-EINVAL
);
1302 int sk_attach_bpf(u32 ufd
, struct sock
*sk
)
1304 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1308 return PTR_ERR(prog
);
1310 err
= __sk_attach_prog(prog
, sk
);
1319 int sk_reuseport_attach_bpf(u32 ufd
, struct sock
*sk
)
1321 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1325 return PTR_ERR(prog
);
1327 err
= __reuseport_attach_prog(prog
, sk
);
1336 #define BPF_LDST_LEN 16U
1338 static u64
bpf_skb_store_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 flags
)
1340 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1341 int offset
= (int) r2
;
1342 void *from
= (void *) (long) r3
;
1343 unsigned int len
= (unsigned int) r4
;
1344 char buf
[BPF_LDST_LEN
];
1347 if (unlikely(flags
& ~(BPF_F_RECOMPUTE_CSUM
)))
1350 /* bpf verifier guarantees that:
1351 * 'from' pointer points to bpf program stack
1352 * 'len' bytes of it were initialized
1354 * 'skb' is a valid pointer to 'struct sk_buff'
1356 * so check for invalid 'offset' and too large 'len'
1358 if (unlikely((u32
) offset
> 0xffff || len
> sizeof(buf
)))
1361 if (unlikely(skb_cloned(skb
) &&
1362 !skb_clone_writable(skb
, offset
+ len
)))
1365 ptr
= skb_header_pointer(skb
, offset
, len
, buf
);
1369 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1370 skb_postpull_rcsum(skb
, ptr
, len
);
1372 memcpy(ptr
, from
, len
);
1375 /* skb_store_bits cannot return -EFAULT here */
1376 skb_store_bits(skb
, offset
, ptr
, len
);
1378 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1379 skb_postpush_rcsum(skb
, ptr
, len
);
1384 const struct bpf_func_proto bpf_skb_store_bytes_proto
= {
1385 .func
= bpf_skb_store_bytes
,
1387 .ret_type
= RET_INTEGER
,
1388 .arg1_type
= ARG_PTR_TO_CTX
,
1389 .arg2_type
= ARG_ANYTHING
,
1390 .arg3_type
= ARG_PTR_TO_STACK
,
1391 .arg4_type
= ARG_CONST_STACK_SIZE
,
1392 .arg5_type
= ARG_ANYTHING
,
1395 static u64
bpf_skb_load_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1397 const struct sk_buff
*skb
= (const struct sk_buff
*)(unsigned long) r1
;
1398 int offset
= (int) r2
;
1399 void *to
= (void *)(unsigned long) r3
;
1400 unsigned int len
= (unsigned int) r4
;
1403 if (unlikely((u32
) offset
> 0xffff || len
> BPF_LDST_LEN
))
1406 ptr
= skb_header_pointer(skb
, offset
, len
, to
);
1410 memcpy(to
, ptr
, len
);
1415 const struct bpf_func_proto bpf_skb_load_bytes_proto
= {
1416 .func
= bpf_skb_load_bytes
,
1418 .ret_type
= RET_INTEGER
,
1419 .arg1_type
= ARG_PTR_TO_CTX
,
1420 .arg2_type
= ARG_ANYTHING
,
1421 .arg3_type
= ARG_PTR_TO_STACK
,
1422 .arg4_type
= ARG_CONST_STACK_SIZE
,
1425 static u64
bpf_l3_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1427 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1428 int offset
= (int) r2
;
1431 if (unlikely(flags
& ~(BPF_F_HDR_FIELD_MASK
)))
1433 if (unlikely((u32
) offset
> 0xffff))
1436 if (unlikely(skb_cloned(skb
) &&
1437 !skb_clone_writable(skb
, offset
+ sizeof(sum
))))
1440 ptr
= skb_header_pointer(skb
, offset
, sizeof(sum
), &sum
);
1444 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1446 csum_replace2(ptr
, from
, to
);
1449 csum_replace4(ptr
, from
, to
);
1456 /* skb_store_bits guaranteed to not return -EFAULT here */
1457 skb_store_bits(skb
, offset
, ptr
, sizeof(sum
));
1462 const struct bpf_func_proto bpf_l3_csum_replace_proto
= {
1463 .func
= bpf_l3_csum_replace
,
1465 .ret_type
= RET_INTEGER
,
1466 .arg1_type
= ARG_PTR_TO_CTX
,
1467 .arg2_type
= ARG_ANYTHING
,
1468 .arg3_type
= ARG_ANYTHING
,
1469 .arg4_type
= ARG_ANYTHING
,
1470 .arg5_type
= ARG_ANYTHING
,
1473 static u64
bpf_l4_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1475 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1476 bool is_pseudo
= flags
& BPF_F_PSEUDO_HDR
;
1477 int offset
= (int) r2
;
1480 if (unlikely(flags
& ~(BPF_F_PSEUDO_HDR
| BPF_F_HDR_FIELD_MASK
)))
1482 if (unlikely((u32
) offset
> 0xffff))
1485 if (unlikely(skb_cloned(skb
) &&
1486 !skb_clone_writable(skb
, offset
+ sizeof(sum
))))
1489 ptr
= skb_header_pointer(skb
, offset
, sizeof(sum
), &sum
);
1493 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1495 inet_proto_csum_replace2(ptr
, skb
, from
, to
, is_pseudo
);
1498 inet_proto_csum_replace4(ptr
, skb
, from
, to
, is_pseudo
);
1505 /* skb_store_bits guaranteed to not return -EFAULT here */
1506 skb_store_bits(skb
, offset
, ptr
, sizeof(sum
));
1511 const struct bpf_func_proto bpf_l4_csum_replace_proto
= {
1512 .func
= bpf_l4_csum_replace
,
1514 .ret_type
= RET_INTEGER
,
1515 .arg1_type
= ARG_PTR_TO_CTX
,
1516 .arg2_type
= ARG_ANYTHING
,
1517 .arg3_type
= ARG_ANYTHING
,
1518 .arg4_type
= ARG_ANYTHING
,
1519 .arg5_type
= ARG_ANYTHING
,
1522 static u64
bpf_clone_redirect(u64 r1
, u64 ifindex
, u64 flags
, u64 r4
, u64 r5
)
1524 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
, *skb2
;
1525 struct net_device
*dev
;
1527 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1530 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ifindex
);
1534 skb2
= skb_clone(skb
, GFP_ATOMIC
);
1535 if (unlikely(!skb2
))
1538 if (flags
& BPF_F_INGRESS
) {
1539 if (skb_at_tc_ingress(skb2
))
1540 skb_postpush_rcsum(skb2
, skb_mac_header(skb2
),
1542 return dev_forward_skb(dev
, skb2
);
1546 skb_sender_cpu_clear(skb2
);
1547 return dev_queue_xmit(skb2
);
1550 const struct bpf_func_proto bpf_clone_redirect_proto
= {
1551 .func
= bpf_clone_redirect
,
1553 .ret_type
= RET_INTEGER
,
1554 .arg1_type
= ARG_PTR_TO_CTX
,
1555 .arg2_type
= ARG_ANYTHING
,
1556 .arg3_type
= ARG_ANYTHING
,
1559 struct redirect_info
{
1564 static DEFINE_PER_CPU(struct redirect_info
, redirect_info
);
1566 static u64
bpf_redirect(u64 ifindex
, u64 flags
, u64 r3
, u64 r4
, u64 r5
)
1568 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1570 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1573 ri
->ifindex
= ifindex
;
1576 return TC_ACT_REDIRECT
;
1579 int skb_do_redirect(struct sk_buff
*skb
)
1581 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1582 struct net_device
*dev
;
1584 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ri
->ifindex
);
1586 if (unlikely(!dev
)) {
1591 if (ri
->flags
& BPF_F_INGRESS
) {
1592 if (skb_at_tc_ingress(skb
))
1593 skb_postpush_rcsum(skb
, skb_mac_header(skb
),
1595 return dev_forward_skb(dev
, skb
);
1599 skb_sender_cpu_clear(skb
);
1600 return dev_queue_xmit(skb
);
1603 const struct bpf_func_proto bpf_redirect_proto
= {
1604 .func
= bpf_redirect
,
1606 .ret_type
= RET_INTEGER
,
1607 .arg1_type
= ARG_ANYTHING
,
1608 .arg2_type
= ARG_ANYTHING
,
1611 static u64
bpf_get_cgroup_classid(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1613 return task_get_classid((struct sk_buff
*) (unsigned long) r1
);
1616 static const struct bpf_func_proto bpf_get_cgroup_classid_proto
= {
1617 .func
= bpf_get_cgroup_classid
,
1619 .ret_type
= RET_INTEGER
,
1620 .arg1_type
= ARG_PTR_TO_CTX
,
1623 static u64
bpf_get_route_realm(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1625 #ifdef CONFIG_IP_ROUTE_CLASSID
1626 const struct dst_entry
*dst
;
1628 dst
= skb_dst((struct sk_buff
*) (unsigned long) r1
);
1630 return dst
->tclassid
;
1635 static const struct bpf_func_proto bpf_get_route_realm_proto
= {
1636 .func
= bpf_get_route_realm
,
1638 .ret_type
= RET_INTEGER
,
1639 .arg1_type
= ARG_PTR_TO_CTX
,
1642 static u64
bpf_skb_vlan_push(u64 r1
, u64 r2
, u64 vlan_tci
, u64 r4
, u64 r5
)
1644 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1645 __be16 vlan_proto
= (__force __be16
) r2
;
1647 if (unlikely(vlan_proto
!= htons(ETH_P_8021Q
) &&
1648 vlan_proto
!= htons(ETH_P_8021AD
)))
1649 vlan_proto
= htons(ETH_P_8021Q
);
1651 return skb_vlan_push(skb
, vlan_proto
, vlan_tci
);
1654 const struct bpf_func_proto bpf_skb_vlan_push_proto
= {
1655 .func
= bpf_skb_vlan_push
,
1657 .ret_type
= RET_INTEGER
,
1658 .arg1_type
= ARG_PTR_TO_CTX
,
1659 .arg2_type
= ARG_ANYTHING
,
1660 .arg3_type
= ARG_ANYTHING
,
1662 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto
);
1664 static u64
bpf_skb_vlan_pop(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1666 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1668 return skb_vlan_pop(skb
);
1671 const struct bpf_func_proto bpf_skb_vlan_pop_proto
= {
1672 .func
= bpf_skb_vlan_pop
,
1674 .ret_type
= RET_INTEGER
,
1675 .arg1_type
= ARG_PTR_TO_CTX
,
1677 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto
);
1679 bool bpf_helper_changes_skb_data(void *func
)
1681 if (func
== bpf_skb_vlan_push
)
1683 if (func
== bpf_skb_vlan_pop
)
1688 static unsigned short bpf_tunnel_key_af(u64 flags
)
1690 return flags
& BPF_F_TUNINFO_IPV6
? AF_INET6
: AF_INET
;
1693 static u64
bpf_skb_get_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
1695 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1696 struct bpf_tunnel_key
*to
= (struct bpf_tunnel_key
*) (long) r2
;
1697 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1698 u8 compat
[sizeof(struct bpf_tunnel_key
)];
1700 if (unlikely(!info
|| (flags
& ~(BPF_F_TUNINFO_IPV6
))))
1702 if (ip_tunnel_info_af(info
) != bpf_tunnel_key_af(flags
))
1704 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
1706 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
1707 /* Fixup deprecated structure layouts here, so we have
1708 * a common path later on.
1710 if (ip_tunnel_info_af(info
) != AF_INET
)
1712 to
= (struct bpf_tunnel_key
*)compat
;
1719 to
->tunnel_id
= be64_to_cpu(info
->key
.tun_id
);
1720 to
->tunnel_tos
= info
->key
.tos
;
1721 to
->tunnel_ttl
= info
->key
.ttl
;
1723 if (flags
& BPF_F_TUNINFO_IPV6
)
1724 memcpy(to
->remote_ipv6
, &info
->key
.u
.ipv6
.src
,
1725 sizeof(to
->remote_ipv6
));
1727 to
->remote_ipv4
= be32_to_cpu(info
->key
.u
.ipv4
.src
);
1729 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
)))
1730 memcpy((void *)(long) r2
, to
, size
);
1735 const struct bpf_func_proto bpf_skb_get_tunnel_key_proto
= {
1736 .func
= bpf_skb_get_tunnel_key
,
1738 .ret_type
= RET_INTEGER
,
1739 .arg1_type
= ARG_PTR_TO_CTX
,
1740 .arg2_type
= ARG_PTR_TO_STACK
,
1741 .arg3_type
= ARG_CONST_STACK_SIZE
,
1742 .arg4_type
= ARG_ANYTHING
,
1745 static struct metadata_dst __percpu
*md_dst
;
1747 static u64
bpf_skb_set_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
1749 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1750 struct bpf_tunnel_key
*from
= (struct bpf_tunnel_key
*) (long) r2
;
1751 struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
1752 u8 compat
[sizeof(struct bpf_tunnel_key
)];
1753 struct ip_tunnel_info
*info
;
1755 if (unlikely(flags
& ~(BPF_F_TUNINFO_IPV6
)))
1757 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
1759 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
1760 /* Fixup deprecated structure layouts here, so we have
1761 * a common path later on.
1763 memcpy(compat
, from
, size
);
1764 memset(compat
+ size
, 0, sizeof(compat
) - size
);
1765 from
= (struct bpf_tunnel_key
*)compat
;
1773 dst_hold((struct dst_entry
*) md
);
1774 skb_dst_set(skb
, (struct dst_entry
*) md
);
1776 info
= &md
->u
.tun_info
;
1777 info
->mode
= IP_TUNNEL_INFO_TX
;
1779 info
->key
.tun_flags
= TUNNEL_KEY
;
1780 info
->key
.tun_id
= cpu_to_be64(from
->tunnel_id
);
1781 info
->key
.tos
= from
->tunnel_tos
;
1782 info
->key
.ttl
= from
->tunnel_ttl
;
1784 if (flags
& BPF_F_TUNINFO_IPV6
) {
1785 info
->mode
|= IP_TUNNEL_INFO_IPV6
;
1786 memcpy(&info
->key
.u
.ipv6
.dst
, from
->remote_ipv6
,
1787 sizeof(from
->remote_ipv6
));
1789 info
->key
.u
.ipv4
.dst
= cpu_to_be32(from
->remote_ipv4
);
1795 const struct bpf_func_proto bpf_skb_set_tunnel_key_proto
= {
1796 .func
= bpf_skb_set_tunnel_key
,
1798 .ret_type
= RET_INTEGER
,
1799 .arg1_type
= ARG_PTR_TO_CTX
,
1800 .arg2_type
= ARG_PTR_TO_STACK
,
1801 .arg3_type
= ARG_CONST_STACK_SIZE
,
1802 .arg4_type
= ARG_ANYTHING
,
1805 static const struct bpf_func_proto
*bpf_get_skb_set_tunnel_key_proto(void)
1808 /* race is not possible, since it's called from
1809 * verifier that is holding verifier mutex
1811 md_dst
= metadata_dst_alloc_percpu(0, GFP_KERNEL
);
1815 return &bpf_skb_set_tunnel_key_proto
;
1818 static const struct bpf_func_proto
*
1819 sk_filter_func_proto(enum bpf_func_id func_id
)
1822 case BPF_FUNC_map_lookup_elem
:
1823 return &bpf_map_lookup_elem_proto
;
1824 case BPF_FUNC_map_update_elem
:
1825 return &bpf_map_update_elem_proto
;
1826 case BPF_FUNC_map_delete_elem
:
1827 return &bpf_map_delete_elem_proto
;
1828 case BPF_FUNC_get_prandom_u32
:
1829 return &bpf_get_prandom_u32_proto
;
1830 case BPF_FUNC_get_smp_processor_id
:
1831 return &bpf_get_smp_processor_id_proto
;
1832 case BPF_FUNC_tail_call
:
1833 return &bpf_tail_call_proto
;
1834 case BPF_FUNC_ktime_get_ns
:
1835 return &bpf_ktime_get_ns_proto
;
1836 case BPF_FUNC_trace_printk
:
1837 if (capable(CAP_SYS_ADMIN
))
1838 return bpf_get_trace_printk_proto();
1844 static const struct bpf_func_proto
*
1845 tc_cls_act_func_proto(enum bpf_func_id func_id
)
1848 case BPF_FUNC_skb_store_bytes
:
1849 return &bpf_skb_store_bytes_proto
;
1850 case BPF_FUNC_skb_load_bytes
:
1851 return &bpf_skb_load_bytes_proto
;
1852 case BPF_FUNC_l3_csum_replace
:
1853 return &bpf_l3_csum_replace_proto
;
1854 case BPF_FUNC_l4_csum_replace
:
1855 return &bpf_l4_csum_replace_proto
;
1856 case BPF_FUNC_clone_redirect
:
1857 return &bpf_clone_redirect_proto
;
1858 case BPF_FUNC_get_cgroup_classid
:
1859 return &bpf_get_cgroup_classid_proto
;
1860 case BPF_FUNC_skb_vlan_push
:
1861 return &bpf_skb_vlan_push_proto
;
1862 case BPF_FUNC_skb_vlan_pop
:
1863 return &bpf_skb_vlan_pop_proto
;
1864 case BPF_FUNC_skb_get_tunnel_key
:
1865 return &bpf_skb_get_tunnel_key_proto
;
1866 case BPF_FUNC_skb_set_tunnel_key
:
1867 return bpf_get_skb_set_tunnel_key_proto();
1868 case BPF_FUNC_redirect
:
1869 return &bpf_redirect_proto
;
1870 case BPF_FUNC_get_route_realm
:
1871 return &bpf_get_route_realm_proto
;
1873 return sk_filter_func_proto(func_id
);
1877 static bool __is_valid_access(int off
, int size
, enum bpf_access_type type
)
1880 if (off
< 0 || off
>= sizeof(struct __sk_buff
))
1883 /* disallow misaligned access */
1884 if (off
% size
!= 0)
1887 /* all __sk_buff fields are __u32 */
1894 static bool sk_filter_is_valid_access(int off
, int size
,
1895 enum bpf_access_type type
)
1897 if (off
== offsetof(struct __sk_buff
, tc_classid
))
1900 if (type
== BPF_WRITE
) {
1902 case offsetof(struct __sk_buff
, cb
[0]) ...
1903 offsetof(struct __sk_buff
, cb
[4]):
1910 return __is_valid_access(off
, size
, type
);
1913 static bool tc_cls_act_is_valid_access(int off
, int size
,
1914 enum bpf_access_type type
)
1916 if (off
== offsetof(struct __sk_buff
, tc_classid
))
1917 return type
== BPF_WRITE
? true : false;
1919 if (type
== BPF_WRITE
) {
1921 case offsetof(struct __sk_buff
, mark
):
1922 case offsetof(struct __sk_buff
, tc_index
):
1923 case offsetof(struct __sk_buff
, priority
):
1924 case offsetof(struct __sk_buff
, cb
[0]) ...
1925 offsetof(struct __sk_buff
, cb
[4]):
1931 return __is_valid_access(off
, size
, type
);
1934 static u32
bpf_net_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
1935 int src_reg
, int ctx_off
,
1936 struct bpf_insn
*insn_buf
,
1937 struct bpf_prog
*prog
)
1939 struct bpf_insn
*insn
= insn_buf
;
1942 case offsetof(struct __sk_buff
, len
):
1943 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, len
) != 4);
1945 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
1946 offsetof(struct sk_buff
, len
));
1949 case offsetof(struct __sk_buff
, protocol
):
1950 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
1952 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
1953 offsetof(struct sk_buff
, protocol
));
1956 case offsetof(struct __sk_buff
, vlan_proto
):
1957 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
1959 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
1960 offsetof(struct sk_buff
, vlan_proto
));
1963 case offsetof(struct __sk_buff
, priority
):
1964 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, priority
) != 4);
1966 if (type
== BPF_WRITE
)
1967 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
1968 offsetof(struct sk_buff
, priority
));
1970 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
1971 offsetof(struct sk_buff
, priority
));
1974 case offsetof(struct __sk_buff
, ingress_ifindex
):
1975 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, skb_iif
) != 4);
1977 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
1978 offsetof(struct sk_buff
, skb_iif
));
1981 case offsetof(struct __sk_buff
, ifindex
):
1982 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
1984 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
1986 offsetof(struct sk_buff
, dev
));
1987 *insn
++ = BPF_JMP_IMM(BPF_JEQ
, dst_reg
, 0, 1);
1988 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, dst_reg
,
1989 offsetof(struct net_device
, ifindex
));
1992 case offsetof(struct __sk_buff
, hash
):
1993 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
1995 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
1996 offsetof(struct sk_buff
, hash
));
1999 case offsetof(struct __sk_buff
, mark
):
2000 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
2002 if (type
== BPF_WRITE
)
2003 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2004 offsetof(struct sk_buff
, mark
));
2006 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2007 offsetof(struct sk_buff
, mark
));
2010 case offsetof(struct __sk_buff
, pkt_type
):
2011 return convert_skb_access(SKF_AD_PKTTYPE
, dst_reg
, src_reg
, insn
);
2013 case offsetof(struct __sk_buff
, queue_mapping
):
2014 return convert_skb_access(SKF_AD_QUEUE
, dst_reg
, src_reg
, insn
);
2016 case offsetof(struct __sk_buff
, vlan_present
):
2017 return convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
2018 dst_reg
, src_reg
, insn
);
2020 case offsetof(struct __sk_buff
, vlan_tci
):
2021 return convert_skb_access(SKF_AD_VLAN_TAG
,
2022 dst_reg
, src_reg
, insn
);
2024 case offsetof(struct __sk_buff
, cb
[0]) ...
2025 offsetof(struct __sk_buff
, cb
[4]):
2026 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb
, data
) < 20);
2028 prog
->cb_access
= 1;
2029 ctx_off
-= offsetof(struct __sk_buff
, cb
[0]);
2030 ctx_off
+= offsetof(struct sk_buff
, cb
);
2031 ctx_off
+= offsetof(struct qdisc_skb_cb
, data
);
2032 if (type
== BPF_WRITE
)
2033 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2035 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2038 case offsetof(struct __sk_buff
, tc_classid
):
2039 ctx_off
-= offsetof(struct __sk_buff
, tc_classid
);
2040 ctx_off
+= offsetof(struct sk_buff
, cb
);
2041 ctx_off
+= offsetof(struct qdisc_skb_cb
, tc_classid
);
2042 WARN_ON(type
!= BPF_WRITE
);
2043 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2046 case offsetof(struct __sk_buff
, tc_index
):
2047 #ifdef CONFIG_NET_SCHED
2048 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, tc_index
) != 2);
2050 if (type
== BPF_WRITE
)
2051 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
,
2052 offsetof(struct sk_buff
, tc_index
));
2054 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2055 offsetof(struct sk_buff
, tc_index
));
2058 if (type
== BPF_WRITE
)
2059 *insn
++ = BPF_MOV64_REG(dst_reg
, dst_reg
);
2061 *insn
++ = BPF_MOV64_IMM(dst_reg
, 0);
2066 return insn
- insn_buf
;
2069 static const struct bpf_verifier_ops sk_filter_ops
= {
2070 .get_func_proto
= sk_filter_func_proto
,
2071 .is_valid_access
= sk_filter_is_valid_access
,
2072 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2075 static const struct bpf_verifier_ops tc_cls_act_ops
= {
2076 .get_func_proto
= tc_cls_act_func_proto
,
2077 .is_valid_access
= tc_cls_act_is_valid_access
,
2078 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2081 static struct bpf_prog_type_list sk_filter_type __read_mostly
= {
2082 .ops
= &sk_filter_ops
,
2083 .type
= BPF_PROG_TYPE_SOCKET_FILTER
,
2086 static struct bpf_prog_type_list sched_cls_type __read_mostly
= {
2087 .ops
= &tc_cls_act_ops
,
2088 .type
= BPF_PROG_TYPE_SCHED_CLS
,
2091 static struct bpf_prog_type_list sched_act_type __read_mostly
= {
2092 .ops
= &tc_cls_act_ops
,
2093 .type
= BPF_PROG_TYPE_SCHED_ACT
,
2096 static int __init
register_sk_filter_ops(void)
2098 bpf_register_prog_type(&sk_filter_type
);
2099 bpf_register_prog_type(&sched_cls_type
);
2100 bpf_register_prog_type(&sched_act_type
);
2104 late_initcall(register_sk_filter_ops
);
2106 int sk_detach_filter(struct sock
*sk
)
2109 struct sk_filter
*filter
;
2111 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
2114 filter
= rcu_dereference_protected(sk
->sk_filter
,
2115 sock_owned_by_user(sk
));
2117 RCU_INIT_POINTER(sk
->sk_filter
, NULL
);
2118 sk_filter_uncharge(sk
, filter
);
2124 EXPORT_SYMBOL_GPL(sk_detach_filter
);
2126 int sk_get_filter(struct sock
*sk
, struct sock_filter __user
*ubuf
,
2129 struct sock_fprog_kern
*fprog
;
2130 struct sk_filter
*filter
;
2134 filter
= rcu_dereference_protected(sk
->sk_filter
,
2135 sock_owned_by_user(sk
));
2139 /* We're copying the filter that has been originally attached,
2140 * so no conversion/decode needed anymore. eBPF programs that
2141 * have no original program cannot be dumped through this.
2144 fprog
= filter
->prog
->orig_prog
;
2150 /* User space only enquires number of filter blocks. */
2154 if (len
< fprog
->len
)
2158 if (copy_to_user(ubuf
, fprog
->filter
, bpf_classic_proglen(fprog
)))
2161 /* Instead of bytes, the API requests to return the number