diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/include/uapi/linux/bpf.h | 145 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 130 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 27 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_probes.c | 73 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/.gitignore | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/jump.c | 195 |
6 files changed, 469 insertions, 103 deletions
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 72336bac7573..63e0cf66f01a 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -629,7 +629,7 @@ union bpf_attr { * **BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\ * **->swhash** and *skb*\ **->l4hash** to 0). * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -654,7 +654,7 @@ union bpf_attr { * flexibility and can handle sizes larger than 2 or 4 for the * checksum to update. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -686,7 +686,7 @@ union bpf_attr { * flexibility and can handle sizes larger than 2 or 4 for the * checksum to update. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -741,7 +741,7 @@ union bpf_attr { * efficient, but it is handled through an action code where the * redirection happens only after the eBPF program has returned. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -806,7 +806,7 @@ union bpf_attr { * **ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to * be **ETH_P_8021Q**. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -818,7 +818,7 @@ union bpf_attr { * Description * Pop a VLAN header from the packet associated to *skb*. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1168,7 +1168,7 @@ union bpf_attr { * All values for *flags* are reserved for future usage, and must * be left at zero. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1281,7 +1281,7 @@ union bpf_attr { * implicitly linearizes, unclones and drops offloads from the * *skb*. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1317,7 +1317,7 @@ union bpf_attr { * **bpf_skb_pull_data()** to effectively unclone the *skb* from * the very beginning in case it is indeed cloned. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1369,7 +1369,7 @@ union bpf_attr { * All values for *flags* are reserved for future usage, and must * be left at zero. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1384,7 +1384,7 @@ union bpf_attr { * can be used to prepare the packet for pushing or popping * headers. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1518,20 +1518,20 @@ union bpf_attr { * * **BPF_F_ADJ_ROOM_FIXED_GSO**: Do not adjust gso_size. * Adjusting mss in this way is not allowed for datagrams. * - * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 **: - * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 **: + * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4**, + * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6**: * Any new space is reserved to hold a tunnel header. * Configure skb offsets and other fields accordingly. * - * * **BPF_F_ADJ_ROOM_ENCAP_L4_GRE **: - * * **BPF_F_ADJ_ROOM_ENCAP_L4_UDP **: + * * **BPF_F_ADJ_ROOM_ENCAP_L4_GRE**, + * **BPF_F_ADJ_ROOM_ENCAP_L4_UDP**: * Use with ENCAP_L3 flags to further specify the tunnel type. * - * * **BPF_F_ADJ_ROOM_ENCAP_L2(len) **: + * * **BPF_F_ADJ_ROOM_ENCAP_L2**\ (*len*): * Use with ENCAP_L3/L4 flags to further specify the tunnel - * type; **len** is the length of the inner MAC header. + * type; *len* is the length of the inner MAC header. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1610,7 +1610,7 @@ union bpf_attr { * more flexibility as the user is free to store whatever meta * data they need. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1852,7 +1852,7 @@ union bpf_attr { * copied if necessary (i.e. if data was not linear and if start * and end pointers do not point to the same chunk). * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -1886,7 +1886,7 @@ union bpf_attr { * only possible to shrink the packet as of this writing, * therefore *delta* must be a negative integer. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -2061,18 +2061,18 @@ union bpf_attr { * **BPF_LWT_ENCAP_IP** * IP encapsulation (GRE/GUE/IPIP/etc). The outer header * must be IPv4 or IPv6, followed by zero or more - * additional headers, up to LWT_BPF_MAX_HEADROOM total - * bytes in all prepended headers. Please note that - * if skb_is_gso(skb) is true, no more than two headers - * can be prepended, and the inner header, if present, - * should be either GRE or UDP/GUE. - * - * BPF_LWT_ENCAP_SEG6*** types can be called by bpf programs of - * type BPF_PROG_TYPE_LWT_IN; BPF_LWT_ENCAP_IP type can be called - * by bpf programs of types BPF_PROG_TYPE_LWT_IN and - * BPF_PROG_TYPE_LWT_XMIT. - * - * A call to this helper is susceptible to change the underlaying + * additional headers, up to **LWT_BPF_MAX_HEADROOM** + * total bytes in all prepended headers. Please note that + * if **skb_is_gso**\ (*skb*) is true, no more than two + * headers can be prepended, and the inner header, if + * present, should be either GRE or UDP/GUE. + * + * **BPF_LWT_ENCAP_SEG6**\ \* types can be called by BPF programs + * of type **BPF_PROG_TYPE_LWT_IN**; **BPF_LWT_ENCAP_IP** type can + * be called by bpf programs of types **BPF_PROG_TYPE_LWT_IN** and + * **BPF_PROG_TYPE_LWT_XMIT**. + * + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -2087,7 +2087,7 @@ union bpf_attr { * inside the outermost IPv6 Segment Routing Header can be * modified through this helper. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -2103,7 +2103,7 @@ union bpf_attr { * after the segments are accepted. *delta* can be as well * positive (growing) as negative (shrinking). * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -2126,13 +2126,13 @@ union bpf_attr { * Type of *param*: **int**. * **SEG6_LOCAL_ACTION_END_B6** * End.B6 action: Endpoint bound to an SRv6 policy. - * Type of param: **struct ipv6_sr_hdr**. + * Type of *param*: **struct ipv6_sr_hdr**. * **SEG6_LOCAL_ACTION_END_B6_ENCAP** * End.B6.Encap action: Endpoint bound to an SRv6 * encapsulation policy. - * Type of param: **struct ipv6_sr_hdr**. + * Type of *param*: **struct ipv6_sr_hdr**. * - * A call to this helper is susceptible to change the underlaying + * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be * performed again, if the helper is used in combination with @@ -2285,7 +2285,8 @@ union bpf_attr { * Return * Pointer to **struct bpf_sock**, or **NULL** in case of failure. * For sockets with reuseport option, the **struct bpf_sock** - * result is from **reuse->socks**\ [] using the hash of the tuple. + * result is from *reuse*\ **->socks**\ [] using the hash of the + * tuple. * * struct bpf_sock *bpf_sk_lookup_udp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags) * Description @@ -2321,7 +2322,8 @@ union bpf_attr { * Return * Pointer to **struct bpf_sock**, or **NULL** in case of failure. * For sockets with reuseport option, the **struct bpf_sock** - * result is from **reuse->socks**\ [] using the hash of the tuple. + * result is from *reuse*\ **->socks**\ [] using the hash of the + * tuple. * * int bpf_sk_release(struct bpf_sock *sock) * Description @@ -2490,31 +2492,34 @@ union bpf_attr { * network namespace *netns*. The return value must be checked, * and if non-**NULL**, released via **bpf_sk_release**\ (). * - * This function is identical to bpf_sk_lookup_tcp, except that it - * also returns timewait or request sockets. Use bpf_sk_fullsock - * or bpf_tcp_socket to access the full structure. + * This function is identical to **bpf_sk_lookup_tcp**\ (), except + * that it also returns timewait or request sockets. Use + * **bpf_sk_fullsock**\ () or **bpf_tcp_sock**\ () to access the + * full structure. * * This helper is available only if the kernel was compiled with * **CONFIG_NET** configuration option. * Return * Pointer to **struct bpf_sock**, or **NULL** in case of failure. * For sockets with reuseport option, the **struct bpf_sock** - * result is from **reuse->socks**\ [] using the hash of the tuple. + * result is from *reuse*\ **->socks**\ [] using the hash of the + * tuple. * * int bpf_tcp_check_syncookie(struct bpf_sock *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len) * Description - * Check whether iph and th contain a valid SYN cookie ACK for - * the listening socket in sk. + * Check whether *iph* and *th* contain a valid SYN cookie ACK for + * the listening socket in *sk*. * - * iph points to the start of the IPv4 or IPv6 header, while - * iph_len contains sizeof(struct iphdr) or sizeof(struct ip6hdr). + * *iph* points to the start of the IPv4 or IPv6 header, while + * *iph_len* contains **sizeof**\ (**struct iphdr**) or + * **sizeof**\ (**struct ip6hdr**). * - * th points to the start of the TCP header, while th_len contains - * sizeof(struct tcphdr). + * *th* points to the start of the TCP header, while *th_len* + * contains **sizeof**\ (**struct tcphdr**). * * Return - * 0 if iph and th are a valid SYN cookie ACK, or a negative error - * otherwise. + * 0 if *iph* and *th* are a valid SYN cookie ACK, or a negative + * error otherwise. * * int bpf_sysctl_get_name(struct bpf_sysctl *ctx, char *buf, size_t buf_len, u64 flags) * Description @@ -2592,17 +2597,17 @@ union bpf_attr { * and save the result in *res*. * * The string may begin with an arbitrary amount of white space - * (as determined by isspace(3)) followed by a single optional '-' - * sign. + * (as determined by **isspace**\ (3)) followed by a single + * optional '**-**' sign. * * Five least significant bits of *flags* encode base, other bits * are currently unused. * * Base must be either 8, 10, 16 or 0 to detect it automatically - * similar to user space strtol(3). + * similar to user space **strtol**\ (3). * Return * Number of characters consumed on success. Must be positive but - * no more than buf_len. + * no more than *buf_len*. * * **-EINVAL** if no valid digits were found or unsupported base * was provided. @@ -2616,16 +2621,16 @@ union bpf_attr { * given base and save the result in *res*. * * The string may begin with an arbitrary amount of white space - * (as determined by isspace(3)). + * (as determined by **isspace**\ (3)). * * Five least significant bits of *flags* encode base, other bits * are currently unused. * * Base must be either 8, 10, 16 or 0 to detect it automatically - * similar to user space strtoul(3). + * similar to user space **strtoul**\ (3). * Return * Number of characters consumed on success. Must be positive but - * no more than buf_len. + * no more than *buf_len*. * * **-EINVAL** if no valid digits were found or unsupported base * was provided. @@ -2634,26 +2639,26 @@ union bpf_attr { * * void *bpf_sk_storage_get(struct bpf_map *map, struct bpf_sock *sk, void *value, u64 flags) * Description - * Get a bpf-local-storage from a sk. + * Get a bpf-local-storage from a *sk*. * * Logically, it could be thought of getting the value from * a *map* with *sk* as the **key**. From this * perspective, the usage is not much different from - * **bpf_map_lookup_elem(map, &sk)** except this - * helper enforces the key must be a **bpf_fullsock()** - * and the map must be a BPF_MAP_TYPE_SK_STORAGE also. + * **bpf_map_lookup_elem**\ (*map*, **&**\ *sk*) except this + * helper enforces the key must be a full socket and the map must + * be a **BPF_MAP_TYPE_SK_STORAGE** also. * * Underneath, the value is stored locally at *sk* instead of - * the map. The *map* is used as the bpf-local-storage **type**. - * The bpf-local-storage **type** (i.e. the *map*) is searched - * against all bpf-local-storages residing at sk. + * the *map*. The *map* is used as the bpf-local-storage + * "type". The bpf-local-storage "type" (i.e. the *map*) is + * searched against all bpf-local-storages residing at *sk*. * - * An optional *flags* (BPF_SK_STORAGE_GET_F_CREATE) can be + * An optional *flags* (**BPF_SK_STORAGE_GET_F_CREATE**) can be * used such that a new bpf-local-storage will be * created if one does not exist. *value* can be used - * together with BPF_SK_STORAGE_GET_F_CREATE to specify + * together with **BPF_SK_STORAGE_GET_F_CREATE** to specify * the initial value of a bpf-local-storage. If *value* is - * NULL, the new bpf-local-storage will be zero initialized. + * **NULL**, the new bpf-local-storage will be zero initialized. * Return * A bpf-local-storage pointer is returned on success. * @@ -2662,7 +2667,7 @@ union bpf_attr { * * int bpf_sk_storage_delete(struct bpf_map *map, struct bpf_sock *sk) * Description - * Delete a bpf-local-storage from a sk. + * Delete a bpf-local-storage from a *sk*. * Return * 0 on success. * diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 11a65db4b93f..7e3b79d7c25f 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -44,6 +44,7 @@ #include "btf.h" #include "str_error.h" #include "libbpf_util.h" +#include "libbpf_internal.h" #ifndef EM_BPF #define EM_BPF 247 @@ -128,6 +129,10 @@ struct bpf_capabilities { __u32 name:1; /* v5.2: kernel support for global data sections. */ __u32 global_data:1; + /* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */ + __u32 btf_func:1; + /* BTF_KIND_VAR and BTF_KIND_DATASEC support */ + __u32 btf_datasec:1; }; /* @@ -1021,6 +1026,74 @@ static bool section_have_execinstr(struct bpf_object *obj, int idx) return false; } +static void bpf_object__sanitize_btf(struct bpf_object *obj) +{ + bool has_datasec = obj->caps.btf_datasec; + bool has_func = obj->caps.btf_func; + struct btf *btf = obj->btf; + struct btf_type *t; + int i, j, vlen; + __u16 kind; + + if (!obj->btf || (has_func && has_datasec)) + return; + + for (i = 1; i <= btf__get_nr_types(btf); i++) { + t = (struct btf_type *)btf__type_by_id(btf, i); + kind = BTF_INFO_KIND(t->info); + + if (!has_datasec && kind == BTF_KIND_VAR) { + /* replace VAR with INT */ + t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); + t->size = sizeof(int); + *(int *)(t+1) = BTF_INT_ENC(0, 0, 32); + } else if (!has_datasec && kind == BTF_KIND_DATASEC) { + /* replace DATASEC with STRUCT */ + struct btf_var_secinfo *v = (void *)(t + 1); + struct btf_member *m = (void *)(t + 1); + struct btf_type *vt; + char *name; + + name = (char *)btf__name_by_offset(btf, t->name_off); + while (*name) { + if (*name == '.') + *name = '_'; + name++; + } + + vlen = BTF_INFO_VLEN(t->info); + t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen); + for (j = 0; j < vlen; j++, v++, m++) { + /* order of field assignments is important */ + m->offset = v->offset * 8; + m->type = v->type; + /* preserve variable name as member name */ + vt = (void *)btf__type_by_id(btf, v->type); + m->name_off = vt->name_off; + } + } else if (!has_func && kind == BTF_KIND_FUNC_PROTO) { + /* replace FUNC_PROTO with ENUM */ + vlen = BTF_INFO_VLEN(t->info); + t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen); + t->size = sizeof(__u32); /* kernel enforced */ + } else if (!has_func && kind == BTF_KIND_FUNC) { + /* replace FUNC with TYPEDEF */ + t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0); + } + } +} + +static void bpf_object__sanitize_btf_ext(struct bpf_object *obj) +{ + if (!obj->btf_ext) + return; + + if (!obj->caps.btf_func) { + btf_ext__free(obj->btf_ext); + obj->btf_ext = NULL; + } +} + static int bpf_object__elf_collect(struct bpf_object *obj, int flags) { Elf *elf = obj->efile.elf; @@ -1164,8 +1237,10 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags) obj->btf = NULL; } else { err = btf__finalize_data(obj, obj->btf); - if (!err) + if (!err) { + bpf_object__sanitize_btf(obj); err = btf__load(obj->btf); + } if (err) { pr_warning("Error finalizing and loading %s into kernel: %d. Ignored and continue.\n", BTF_ELF_SEC, err); @@ -1187,6 +1262,8 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags) BTF_EXT_ELF_SEC, PTR_ERR(obj->btf_ext)); obj->btf_ext = NULL; + } else { + bpf_object__sanitize_btf_ext(obj); } } } @@ -1556,12 +1633,63 @@ bpf_object__probe_global_data(struct bpf_object *obj) return 0; } +static int bpf_object__probe_btf_func(struct bpf_object *obj) +{ + const char strs[] = "\0int\0x\0a"; + /* void x(int a) {} */ + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* FUNC_PROTO */ /* [2] */ + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), + BTF_PARAM_ENC(7, 1), + /* FUNC x */ /* [3] */ + BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), + }; + int res; + + res = libbpf__probe_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs)); + if (res < 0) + return res; + if (res > 0) + obj->caps.btf_func = 1; + return 0; +} + +static int bpf_object__probe_btf_datasec(struct bpf_object *obj) +{ + const char strs[] = "\0x\0.data"; + /* static int a; */ + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* VAR x */ /* [2] */ + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), + BTF_VAR_STATIC, + /* DATASEC val */ /* [3] */ + BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), + BTF_VAR_SECINFO_ENC(2, 0, 4), + }; + int res; + + res = libbpf__probe_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs)); + if (res < 0) + return res; + if (res > 0) + obj->caps.btf_datasec = 1; + return 0; +} + static int bpf_object__probe_caps(struct bpf_object *obj) { int (*probe_fn[])(struct bpf_object *obj) = { bpf_object__probe_name, bpf_object__probe_global_data, + bpf_object__probe_btf_func, + bpf_object__probe_btf_datasec, }; int i, ret; diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h new file mode 100644 index 000000000000..789e435b5900 --- /dev/null +++ b/tools/lib/bpf/libbpf_internal.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ + +/* + * Internal libbpf helpers. + * + * Copyright (c) 2019 Facebook + */ + +#ifndef __LIBBPF_LIBBPF_INTERNAL_H +#define __LIBBPF_LIBBPF_INTERNAL_H + +#define BTF_INFO_ENC(kind, kind_flag, vlen) \ + ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN)) +#define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type) +#define BTF_INT_ENC(encoding, bits_offset, nr_bits) \ + ((encoding) << 24 | (bits_offset) << 16 | (nr_bits)) +#define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \ + BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \ + BTF_INT_ENC(encoding, bits_offset, bits) +#define BTF_MEMBER_ENC(name, type, bits_offset) (name), (type), (bits_offset) +#define BTF_PARAM_ENC(name, type) (name), (type) +#define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size) + +int libbpf__probe_raw_btf(const char *raw_types, size_t types_len, + const char *str_sec, size_t str_len); + +#endif /* __LIBBPF_LIBBPF_INTERNAL_H */ diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index a2c64a9ce1a6..5e2aa83f637a 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -15,6 +15,7 @@ #include "bpf.h" #include "libbpf.h" +#include "libbpf_internal.h" static bool grep(const char *buffer, const char *pattern) { @@ -132,21 +133,43 @@ bool bpf_probe_prog_type(enum bpf_prog_type prog_type, __u32 ifindex) return errno != EINVAL && errno != EOPNOTSUPP; } -static int load_btf(void) +int libbpf__probe_raw_btf(const char *raw_types, size_t types_len, + const char *str_sec, size_t str_len) { -#define BTF_INFO_ENC(kind, kind_flag, vlen) \ - ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN)) -#define BTF_TYPE_ENC(name, info, size_or_type) \ - (name), (info), (size_or_type) -#define BTF_INT_ENC(encoding, bits_offset, nr_bits) \ - ((encoding) << 24 | (bits_offset) << 16 | (nr_bits)) -#define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \ - BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \ - BTF_INT_ENC(encoding, bits_offset, bits) -#define BTF_MEMBER_ENC(name, type, bits_offset) \ - (name), (type), (bits_offset) - - const char btf_str_sec[] = "\0bpf_spin_lock\0val\0cnt\0l"; + struct btf_header hdr = { + .magic = BTF_MAGIC, + .version = BTF_VERSION, + .hdr_len = sizeof(struct btf_header), + .type_len = types_len, + .str_off = types_len, + .str_len = str_len, + }; + int btf_fd, btf_len; + __u8 *raw_btf; + + btf_len = hdr.hdr_len + hdr.type_len + hdr.str_len; + raw_btf = malloc(btf_len); + if (!raw_btf) + return -ENOMEM; + + memcpy(raw_btf, &hdr, sizeof(hdr)); + memcpy(raw_btf + hdr.hdr_len, raw_types, hdr.type_len); + memcpy(raw_btf + hdr.hdr_len + hdr.type_len, str_sec, hdr.str_len); + + btf_fd = bpf_load_btf(raw_btf, btf_len, NULL, 0, false); + if (btf_fd < 0) { + free(raw_btf); + return 0; + } + + close(btf_fd); + free(raw_btf); + return 1; +} + +static int load_sk_storage_btf(void) +{ + const char strs[] = "\0bpf_spin_lock\0val\0cnt\0l"; /* struct bpf_spin_lock { * int val; * }; @@ -155,7 +178,7 @@ static int load_btf(void) * struct bpf_spin_lock l; * }; */ - __u32 btf_raw_types[] = { + __u32 types[] = { /* int */ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ /* struct bpf_spin_lock */ /* [2] */ @@ -166,23 +189,9 @@ static int load_btf(void) BTF_MEMBER_ENC(19, 1, 0), /* int cnt; */ BTF_MEMBER_ENC(23, 2, 32),/* struct bpf_spin_lock l; */ }; - struct btf_header btf_hdr = { - .magic = BTF_MAGIC, - .version = BTF_VERSION, - .hdr_len = sizeof(struct btf_header), - .type_len = sizeof(btf_raw_types), - .str_off = sizeof(btf_raw_types), - .str_len = sizeof(btf_str_sec), - }; - __u8 raw_btf[sizeof(struct btf_header) + sizeof(btf_raw_types) + - sizeof(btf_str_sec)]; - - memcpy(raw_btf, &btf_hdr, sizeof(btf_hdr)); - memcpy(raw_btf + sizeof(btf_hdr), btf_raw_types, sizeof(btf_raw_types)); - memcpy(raw_btf + sizeof(btf_hdr) + sizeof(btf_raw_types), - btf_str_sec, sizeof(btf_str_sec)); - return bpf_load_btf(raw_btf, sizeof(raw_btf), 0, 0, 0); + return libbpf__probe_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs)); } bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex) @@ -222,7 +231,7 @@ bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex) value_size = 8; max_entries = 0; map_flags = BPF_F_NO_PREALLOC; - btf_fd = load_btf(); + btf_fd = load_sk_storage_btf(); if (btf_fd < 0) return false; break; diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index 41e8a689aa77..a877803e4ba8 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -32,3 +32,5 @@ test_tcpnotify_user test_libbpf test_tcp_check_syncookie_user alu32 +libbpf.pc +libbpf.so.* diff --git a/tools/testing/selftests/bpf/verifier/jump.c b/tools/testing/selftests/bpf/verifier/jump.c index 8e6fcc8940f0..6f951d1ff0a4 100644 --- a/tools/testing/selftests/bpf/verifier/jump.c +++ b/tools/testing/selftests/bpf/verifier/jump.c @@ -178,3 +178,198 @@ .result_unpriv = REJECT, .result = ACCEPT, }, +{ + "jump test 6", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_MOV64_IMM(BPF_REG_1, 2), + BPF_JMP_IMM(BPF_JA, 0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 2), + BPF_EXIT_INSN(), + BPF_JMP_REG(BPF_JNE, BPF_REG_0, BPF_REG_1, 16), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, -20), + }, + .result = ACCEPT, + .retval = 2, +}, +{ + "jump test 7", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_JMP_IMM(BPF_JA, 0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 3), + BPF_EXIT_INSN(), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 2, 16), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_JMP_IMM(BPF_JA, 0, 0, -20), + }, + .result = ACCEPT, + .retval = 3, +}, +{ + "jump test 8", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_MOV64_IMM(BPF_REG_1, 2), + BPF_JMP_IMM(BPF_JA, 0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 3), + BPF_EXIT_INSN(), + BPF_JMP_REG(BPF_JNE, BPF_REG_0, BPF_REG_1, 16), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_JMP_IMM(BPF_JA, 0, 0, -20), + }, + .result = ACCEPT, + .retval = 3, +}, +{ + "jump/call test 9", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_JMP_IMM(BPF_JA, 0, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 3), + BPF_EXIT_INSN(), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 2, 16), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, -20), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = REJECT, + .errstr = "jump out of range from insn 1 to 4", +}, +{ + "jump/call test 10", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2), + BPF_MOV64_IMM(BPF_REG_0, 3), + BPF_EXIT_INSN(), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 2, 16), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, -20), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = REJECT, + .errstr = "last insn is not an exit or jmp", +}, +{ + "jump/call test 11", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 4), + BPF_MOV64_IMM(BPF_REG_0, 3), + BPF_EXIT_INSN(), + BPF_MOV64_IMM(BPF_REG_0, 3), + BPF_EXIT_INSN(), + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 2, 26), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, -31), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = ACCEPT, + .retval = 3, +}, |