diff options
Diffstat (limited to 'tools/lib/bpf/libbpf_probes.c')
| -rw-r--r-- | tools/lib/bpf/libbpf_probes.c | 115 |
1 files changed, 110 insertions, 5 deletions
diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index b44fcbb4b42e..bccf4bb747e1 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -12,11 +12,94 @@ #include <linux/btf.h> #include <linux/filter.h> #include <linux/kernel.h> +#include <linux/version.h> #include "bpf.h" #include "libbpf.h" #include "libbpf_internal.h" +/* On Ubuntu LINUX_VERSION_CODE doesn't correspond to info.release, + * but Ubuntu provides /proc/version_signature file, as described at + * https://ubuntu.com/kernel, with an example contents below, which we + * can use to get a proper LINUX_VERSION_CODE. + * + * Ubuntu 5.4.0-12.15-generic 5.4.8 + * + * In the above, 5.4.8 is what kernel is actually expecting, while + * uname() call will return 5.4.0 in info.release. + */ +static __u32 get_ubuntu_kernel_version(void) +{ + const char *ubuntu_kver_file = "/proc/version_signature"; + __u32 major, minor, patch; + int ret; + FILE *f; + + if (faccessat(AT_FDCWD, ubuntu_kver_file, R_OK, AT_EACCESS) != 0) + return 0; + + f = fopen(ubuntu_kver_file, "re"); + if (!f) + return 0; + + ret = fscanf(f, "%*s %*s %u.%u.%u\n", &major, &minor, &patch); + fclose(f); + if (ret != 3) + return 0; + + return KERNEL_VERSION(major, minor, patch); +} + +/* On Debian LINUX_VERSION_CODE doesn't correspond to info.release. + * Instead, it is provided in info.version. An example content of + * Debian 10 looks like the below. + * + * utsname::release 4.19.0-22-amd64 + * utsname::version #1 SMP Debian 4.19.260-1 (2022-09-29) + * + * In the above, 4.19.260 is what kernel is actually expecting, while + * uname() call will return 4.19.0 in info.release. + */ +static __u32 get_debian_kernel_version(struct utsname *info) +{ + __u32 major, minor, patch; + char *p; + + p = strstr(info->version, "Debian "); + if (!p) { + /* This is not a Debian kernel. */ + return 0; + } + + if (sscanf(p, "Debian %u.%u.%u", &major, &minor, &patch) != 3) + return 0; + + return KERNEL_VERSION(major, minor, patch); +} + +__u32 get_kernel_version(void) +{ + __u32 major, minor, patch, version; + struct utsname info; + + /* Check if this is an Ubuntu kernel. */ + version = get_ubuntu_kernel_version(); + if (version != 0) + return version; + + uname(&info); + + /* Check if this is a Debian kernel. */ + version = get_debian_kernel_version(&info); + if (version != 0) + return version; + + if (sscanf(info.release, "%u.%u.%u", &major, &minor, &patch) != 3) + return 0; + + return KERNEL_VERSION(major, minor, patch); +} + static int probe_prog_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, size_t insns_cnt, char *log_buf, size_t log_buf_sz) @@ -98,6 +181,9 @@ static int probe_prog_load(enum bpf_prog_type prog_type, case BPF_PROG_TYPE_FLOW_DISSECTOR: case BPF_PROG_TYPE_CGROUP_SYSCTL: break; + case BPF_PROG_TYPE_NETFILTER: + opts.expected_attach_type = BPF_NETFILTER; + break; default: return -EOPNOTSUPP; } @@ -133,7 +219,8 @@ int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts) } int libbpf__load_raw_btf(const char *raw_types, size_t types_len, - const char *str_sec, size_t str_len) + const char *str_sec, size_t str_len, + int token_fd) { struct btf_header hdr = { .magic = BTF_MAGIC, @@ -143,6 +230,10 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len, .str_off = types_len, .str_len = str_len, }; + LIBBPF_OPTS(bpf_btf_load_opts, opts, + .token_fd = token_fd, + .btf_flags = token_fd ? BPF_F_TOKEN_FD : 0, + ); int btf_fd, btf_len; __u8 *raw_btf; @@ -155,7 +246,7 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len, 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_btf_load(raw_btf, btf_len, NULL); + btf_fd = bpf_btf_load(raw_btf, btf_len, &opts); free(raw_btf); return btf_fd; @@ -185,7 +276,7 @@ static int load_local_storage_btf(void) }; return libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs)); + strs, sizeof(strs), 0); } static int probe_map_create(enum bpf_map_type map_type) @@ -240,12 +331,20 @@ static int probe_map_create(enum bpf_map_type map_type) case BPF_MAP_TYPE_STRUCT_OPS: /* we'll get -ENOTSUPP for invalid BTF type ID for struct_ops */ opts.btf_vmlinux_value_type_id = 1; + opts.value_type_btf_obj_fd = -1; exp_err = -524; /* -ENOTSUPP */ break; case BPF_MAP_TYPE_BLOOM_FILTER: key_size = 0; max_entries = 1; break; + case BPF_MAP_TYPE_ARENA: + key_size = 0; + value_size = 0; + max_entries = 1; /* one page */ + opts.map_extra = 0; /* can mmap() at any address */ + opts.map_flags = BPF_F_MMAPABLE; + break; case BPF_MAP_TYPE_HASH: case BPF_MAP_TYPE_ARRAY: case BPF_MAP_TYPE_PROG_ARRAY: @@ -265,6 +364,10 @@ static int probe_map_create(enum bpf_map_type map_type) case BPF_MAP_TYPE_SOCKHASH: case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: break; + case BPF_MAP_TYPE_INSN_ARRAY: + key_size = sizeof(__u32); + value_size = sizeof(struct bpf_insn_array_value); + break; case BPF_MAP_TYPE_UNSPEC: default: return -EOPNOTSUPP; @@ -349,7 +452,8 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helpe /* If BPF verifier doesn't recognize BPF helper ID (enum bpf_func_id) * at all, it will emit something like "invalid func unknown#181". * If BPF verifier recognizes BPF helper but it's not supported for - * given BPF program type, it will emit "unknown func bpf_sys_bpf#166". + * given BPF program type, it will emit "unknown func bpf_sys_bpf#166" + * or "program of this type cannot use helper bpf_sys_bpf#166". * In both cases, provided combination of BPF program type and BPF * helper is not supported by the kernel. * In all other cases, probe_prog_load() above will either succeed (e.g., @@ -358,7 +462,8 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helpe * that), or we'll get some more specific BPF verifier error about * some unsatisfied conditions. */ - if (ret == 0 && (strstr(buf, "invalid func ") || strstr(buf, "unknown func "))) + if (ret == 0 && (strstr(buf, "invalid func ") || strstr(buf, "unknown func ") || + strstr(buf, "program of this type cannot use helper "))) return 0; return 1; /* assume supported */ } |