diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index 57890b357f85..bed4b9964581 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -172,7 +172,8 @@ extern struct btf_id_set name; BTF_SOCK_TYPE(BTF_SOCK_TYPE_TCP_TW, tcp_timewait_sock) \ BTF_SOCK_TYPE(BTF_SOCK_TYPE_TCP6, tcp6_sock) \ BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP, udp_sock) \ - BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP6, udp6_sock) + BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP6, udp6_sock) \ + BTF_SOCK_TYPE(BTF_SOCK_TYPE_UNIX, unix_sock) enum { #define BTF_SOCK_TYPE(name, str) name, diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 32761be48143..4e8540716187 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -907,6 +907,20 @@ fmt_str: tmp_buf += err; num_spec++; + continue; + } else if (fmt[i] == 'c') { + if (!tmp_buf) + goto nocopy_fmt; + + if (tmp_buf_end == tmp_buf) { + err = -ENOSPC; + goto out; + } + + *tmp_buf = raw_args[num_spec]; + tmp_buf++; + num_spec++; + continue; } diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 1c2224f05b51..bad8f19174e3 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -113,6 +113,7 @@ #include #include #include +#include #include "scm.h" @@ -3143,6 +3144,64 @@ static const struct seq_operations unix_seq_ops = { .stop = unix_seq_stop, .show = unix_seq_show, }; + +#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) +struct bpf_iter__unix { + __bpf_md_ptr(struct bpf_iter_meta *, meta); + __bpf_md_ptr(struct unix_sock *, unix_sk); + uid_t uid __aligned(8); +}; + +static int unix_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta, + struct unix_sock *unix_sk, uid_t uid) +{ + struct bpf_iter__unix ctx; + + meta->seq_num--; /* skip SEQ_START_TOKEN */ + ctx.meta = meta; + ctx.unix_sk = unix_sk; + ctx.uid = uid; + return bpf_iter_run_prog(prog, &ctx); +} + +static int bpf_iter_unix_seq_show(struct seq_file *seq, void *v) +{ + struct bpf_iter_meta meta; + struct bpf_prog *prog; + struct sock *sk = v; + uid_t uid; + + if (v == SEQ_START_TOKEN) + return 0; + + uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)); + meta.seq = seq; + prog = bpf_iter_get_info(&meta, false); + return unix_prog_seq_show(prog, &meta, v, uid); +} + +static void bpf_iter_unix_seq_stop(struct seq_file *seq, void *v) +{ + struct bpf_iter_meta meta; + struct bpf_prog *prog; + + if (!v) { + meta.seq = seq; + prog = bpf_iter_get_info(&meta, true); + if (prog) + (void)unix_prog_seq_show(prog, &meta, v, 0); + } + + unix_seq_stop(seq, v); +} + +static const struct seq_operations bpf_iter_unix_seq_ops = { + .start = unix_seq_start, + .next = unix_seq_next, + .stop = bpf_iter_unix_seq_stop, + .show = bpf_iter_unix_seq_show, +}; +#endif #endif static const struct net_proto_family unix_family_ops = { @@ -3183,6 +3242,35 @@ static struct pernet_operations unix_net_ops = { .exit = unix_net_exit, }; +#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) +DEFINE_BPF_ITER_FUNC(unix, struct bpf_iter_meta *meta, + struct unix_sock *unix_sk, uid_t uid) + +static const struct bpf_iter_seq_info unix_seq_info = { + .seq_ops = &bpf_iter_unix_seq_ops, + .init_seq_private = bpf_iter_init_seq_net, + .fini_seq_private = bpf_iter_fini_seq_net, + .seq_priv_size = sizeof(struct seq_net_private), +}; + +static struct bpf_iter_reg unix_reg_info = { + .target = "unix", + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__unix, unix_sk), + PTR_TO_BTF_ID_OR_NULL }, + }, + .seq_info = &unix_seq_info, +}; + +static void __init bpf_iter_register(void) +{ + unix_reg_info.ctx_arg_info[0].btf_id = btf_sock_ids[BTF_SOCK_TYPE_UNIX]; + if (bpf_iter_reg_target(&unix_reg_info)) + pr_warn("Warning: could not register bpf iterator unix\n"); +} +#endif + static int __init af_unix_init(void) { int rc = -1; @@ -3198,6 +3286,11 @@ static int __init af_unix_init(void) sock_register(&unix_family_ops); register_pernet_subsys(&unix_net_ops); unix_bpf_build_proto(); + +#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) + bpf_iter_register(); +#endif + out: return rc; } diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 1f1aade56504..77ac24b191d4 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -13,6 +13,7 @@ #include "bpf_iter_tcp6.skel.h" #include "bpf_iter_udp4.skel.h" #include "bpf_iter_udp6.skel.h" +#include "bpf_iter_unix.skel.h" #include "bpf_iter_test_kern1.skel.h" #include "bpf_iter_test_kern2.skel.h" #include "bpf_iter_test_kern3.skel.h" @@ -313,6 +314,19 @@ static void test_udp6(void) bpf_iter_udp6__destroy(skel); } +static void test_unix(void) +{ + struct bpf_iter_unix *skel; + + skel = bpf_iter_unix__open_and_load(); + if (!ASSERT_OK_PTR(skel, "bpf_iter_unix__open_and_load")) + return; + + do_dummy_read(skel->progs.dump_unix); + + bpf_iter_unix__destroy(skel); +} + /* The expected string is less than 16 bytes */ static int do_read_with_fd(int iter_fd, const char *expected, bool read_one_char) @@ -1255,6 +1269,8 @@ void test_bpf_iter(void) test_udp4(); if (test__start_subtest("udp6")) test_udp6(); + if (test__start_subtest("unix")) + test_unix(); if (test__start_subtest("anon")) test_anon_iter(false); if (test__start_subtest("anon-read-one-char")) diff --git a/tools/testing/selftests/bpf/prog_tests/snprintf.c b/tools/testing/selftests/bpf/prog_tests/snprintf.c index dffbcaa1ec98..8fd1b4b29a0e 100644 --- a/tools/testing/selftests/bpf/prog_tests/snprintf.c +++ b/tools/testing/selftests/bpf/prog_tests/snprintf.c @@ -19,7 +19,7 @@ #define EXP_ADDR_OUT "0000000000000000 ffff00000add4e55 " #define EXP_ADDR_RET sizeof(EXP_ADDR_OUT "unknownhashedptr") -#define EXP_STR_OUT "str1 longstr" +#define EXP_STR_OUT "str1 a b c d e longstr" #define EXP_STR_RET sizeof(EXP_STR_OUT) #define EXP_OVER_OUT "%over" @@ -114,6 +114,8 @@ void test_snprintf_negative(void) ASSERT_ERR(load_single_snprintf("%"), "invalid specifier 3"); ASSERT_ERR(load_single_snprintf("%12345678"), "invalid specifier 4"); ASSERT_ERR(load_single_snprintf("%--------"), "invalid specifier 5"); + ASSERT_ERR(load_single_snprintf("%lc"), "invalid specifier 6"); + ASSERT_ERR(load_single_snprintf("%llc"), "invalid specifier 7"); ASSERT_ERR(load_single_snprintf("\x80"), "non ascii character"); ASSERT_ERR(load_single_snprintf("\x1"), "non printable character"); } diff --git a/tools/testing/selftests/bpf/progs/bpf_iter.h b/tools/testing/selftests/bpf/progs/bpf_iter.h index 3d83b185c4bc..8cfaeba1ddbf 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter.h +++ b/tools/testing/selftests/bpf/progs/bpf_iter.h @@ -12,6 +12,7 @@ #define tcp6_sock tcp6_sock___not_used #define bpf_iter__udp bpf_iter__udp___not_used #define udp6_sock udp6_sock___not_used +#define bpf_iter__unix bpf_iter__unix___not_used #define bpf_iter__bpf_map_elem bpf_iter__bpf_map_elem___not_used #define bpf_iter__bpf_sk_storage_map bpf_iter__bpf_sk_storage_map___not_used #define bpf_iter__sockmap bpf_iter__sockmap___not_used @@ -32,6 +33,7 @@ #undef tcp6_sock #undef bpf_iter__udp #undef udp6_sock +#undef bpf_iter__unix #undef bpf_iter__bpf_map_elem #undef bpf_iter__bpf_sk_storage_map #undef bpf_iter__sockmap @@ -103,6 +105,12 @@ struct udp6_sock { struct ipv6_pinfo inet6; } __attribute__((preserve_access_index)); +struct bpf_iter__unix { + struct bpf_iter_meta *meta; + struct unix_sock *unix_sk; + uid_t uid; +} __attribute__((preserve_access_index)); + struct bpf_iter__bpf_map_elem { struct bpf_iter_meta *meta; struct bpf_map *map; diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_unix.c b/tools/testing/selftests/bpf/progs/bpf_iter_unix.c new file mode 100644 index 000000000000..94423902685d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_unix.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright Amazon.com Inc. or its affiliates. */ +#include "bpf_iter.h" +#include "bpf_tracing_net.h" +#include +#include + +char _license[] SEC("license") = "GPL"; + +static long sock_i_ino(const struct sock *sk) +{ + const struct socket *sk_socket = sk->sk_socket; + const struct inode *inode; + unsigned long ino; + + if (!sk_socket) + return 0; + + inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; + bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino); + return ino; +} + +SEC("iter/unix") +int dump_unix(struct bpf_iter__unix *ctx) +{ + struct unix_sock *unix_sk = ctx->unix_sk; + struct sock *sk = (struct sock *)unix_sk; + struct seq_file *seq; + __u32 seq_num; + + if (!unix_sk) + return 0; + + seq = ctx->meta->seq; + seq_num = ctx->meta->seq_num; + if (seq_num == 0) + BPF_SEQ_PRINTF(seq, "Num RefCount Protocol Flags Type St Inode Path\n"); + + BPF_SEQ_PRINTF(seq, "%pK: %08X %08X %08X %04X %02X %8lu", + unix_sk, + sk->sk_refcnt.refs.counter, + 0, + sk->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0, + sk->sk_type, + sk->sk_socket ? + (sk->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : + (sk->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), + sock_i_ino(sk)); + + if (unix_sk->addr) { + if (!UNIX_ABSTRACT(unix_sk)) { + BPF_SEQ_PRINTF(seq, " %s", unix_sk->addr->name->sun_path); + } else { + /* The name of the abstract UNIX domain socket starts + * with '\0' and can contain '\0'. The null bytes + * should be escaped as done in unix_seq_show(). + */ + __u64 i, len; + + len = unix_sk->addr->len - sizeof(short); + + BPF_SEQ_PRINTF(seq, " @"); + + for (i = 1; i < len; i++) { + /* unix_mkname() tests this upper bound. */ + if (i >= sizeof(struct sockaddr_un)) + break; + + BPF_SEQ_PRINTF(seq, "%c", + unix_sk->addr->name->sun_path[i] ?: + '@'); + } + } + } + + BPF_SEQ_PRINTF(seq, "\n"); + + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h index 3af0998a0623..eef5646ddb19 100644 --- a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h +++ b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h @@ -5,6 +5,10 @@ #define AF_INET 2 #define AF_INET6 10 +#define __SO_ACCEPTCON (1 << 16) +#define UNIX_HASH_SIZE 256 +#define UNIX_ABSTRACT(unix_sk) (unix_sk->addr->hash < UNIX_HASH_SIZE) + #define SOL_TCP 6 #define TCP_CONGESTION 13 #define TCP_CA_NAME_MAX 16 diff --git a/tools/testing/selftests/bpf/progs/test_snprintf.c b/tools/testing/selftests/bpf/progs/test_snprintf.c index e2ad26150f9b..8fda07544023 100644 --- a/tools/testing/selftests/bpf/progs/test_snprintf.c +++ b/tools/testing/selftests/bpf/progs/test_snprintf.c @@ -59,9 +59,9 @@ int handler(const void *ctx) /* Kernel pointers */ addr_ret = BPF_SNPRINTF(addr_out, sizeof(addr_out), "%pK %px %p", 0, 0xFFFF00000ADD4E55, 0xFFFF00000ADD4E55); - /* Strings embedding */ - str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s %+05s", - str1, longstr); + /* Strings and single-byte character embedding */ + str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s % 9c %+2c %-3c %04c %0c %+05s", + str1, 'a', 'b', 'c', 'd', 'e', longstr); /* Overflow */ over_ret = BPF_SNPRINTF(over_out, sizeof(over_out), "%%overflow"); /* Padding of fixed width numbers */