diff options
author | Jakub Kicinski <kuba@kernel.org> | 2023-01-27 23:32:02 -0800 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2023-01-27 23:32:03 -0800 |
commit | 0548c5f26a0fefa721b29be2bfff1c44f15b6d73 (patch) | |
tree | 21149a8ae3545dea23fe0bb86ca84d22acf6c50d | |
parent | 7d2c89b325874a35564db5630a459966afab04cc (diff) | |
parent | 5416c9aea8323583e8696f0500b6142dfae80821 (diff) | |
download | linux-rpi-0548c5f26a0fefa721b29be2bfff1c44f15b6d73.tar.gz linux-rpi-0548c5f26a0fefa721b29be2bfff1c44f15b6d73.tar.bz2 linux-rpi-0548c5f26a0fefa721b29be2bfff1c44f15b6d73.zip |
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:
====================
bpf 2023-01-27
We've added 10 non-merge commits during the last 9 day(s) which contain
a total of 10 files changed, 170 insertions(+), 59 deletions(-).
The main changes are:
1) Fix preservation of register's parent/live fields when copying
range-info, from Eduard Zingerman.
2) Fix an off-by-one bug in bpf_mem_cache_idx() to select the right
cache, from Hou Tao.
3) Fix stack overflow from infinite recursion in sock_map_close(),
from Jakub Sitnicki.
4) Fix missing btf_put() in register_btf_id_dtor_kfuncs()'s error path,
from Jiri Olsa.
5) Fix a splat from bpf_setsockopt() via lsm_cgroup/socket_sock_rcv_skb,
from Kui-Feng Lee.
6) Fix bpf_send_signal[_thread]() helpers to hold a reference on the task,
from Yonghong Song.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Fix the kernel crash caused by bpf_setsockopt().
selftests/bpf: Cover listener cloning with progs attached to sockmap
selftests/bpf: Pass BPF skeleton to sockmap_listen ops tests
bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener
bpf, sockmap: Don't let sock_map_{close,destroy,unhash} call itself
bpf: Add missing btf_put to register_btf_id_dtor_kfuncs
selftests/bpf: Verify copy_register_state() preserves parent/live fields
bpf: Fix to preserve reg parent/live fields when copying range info
bpf: Fix a possible task gone issue with bpf_send_signal[_thread]() helpers
bpf: Fix off-by-one error in bpf_mem_cache_idx()
====================
Link: https://lore.kernel.org/r/20230127215820.4993-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-rw-r--r-- | include/linux/util_macros.h | 12 | ||||
-rw-r--r-- | kernel/bpf/bpf_lsm.c | 1 | ||||
-rw-r--r-- | kernel/bpf/btf.c | 4 | ||||
-rw-r--r-- | kernel/bpf/memalloc.c | 2 | ||||
-rw-r--r-- | kernel/bpf/verifier.c | 25 | ||||
-rw-r--r-- | kernel/trace/bpf_trace.c | 3 | ||||
-rw-r--r-- | net/core/sock_map.c | 61 | ||||
-rw-r--r-- | net/ipv4/tcp_bpf.c | 4 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/sockmap_listen.c | 81 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/verifier/search_pruning.c | 36 |
10 files changed, 170 insertions, 59 deletions
diff --git a/include/linux/util_macros.h b/include/linux/util_macros.h index 72299f261b25..43db6e47503c 100644 --- a/include/linux/util_macros.h +++ b/include/linux/util_macros.h @@ -38,4 +38,16 @@ */ #define find_closest_descending(x, a, as) __find_closest(x, a, as, >=) +/** + * is_insidevar - check if the @ptr points inside the @var memory range. + * @ptr: the pointer to a memory address. + * @var: the variable which address and size identify the memory range. + * + * Evaluates to true if the address in @ptr lies within the memory + * range allocated to @var. + */ +#define is_insidevar(ptr, var) \ + ((uintptr_t)(ptr) >= (uintptr_t)(var) && \ + (uintptr_t)(ptr) < (uintptr_t)(var) + sizeof(var)) + #endif diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index a4a41ee3e80b..e14c822f8911 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -51,7 +51,6 @@ BTF_SET_END(bpf_lsm_current_hooks) */ BTF_SET_START(bpf_lsm_locked_sockopt_hooks) #ifdef CONFIG_SECURITY_NETWORK -BTF_ID(func, bpf_lsm_socket_sock_rcv_skb) BTF_ID(func, bpf_lsm_sock_graft) BTF_ID(func, bpf_lsm_inet_csk_clone) BTF_ID(func, bpf_lsm_inet_conn_established) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index f7dd8af06413..b7017cae6fd1 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -7782,9 +7782,9 @@ int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_c sort(tab->dtors, tab->cnt, sizeof(tab->dtors[0]), btf_id_cmp_func, NULL); - return 0; end: - btf_free_dtor_kfunc_tab(btf); + if (ret) + btf_free_dtor_kfunc_tab(btf); btf_put(btf); return ret; } diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index ebcc3dd0fa19..1db156405b68 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -71,7 +71,7 @@ static int bpf_mem_cache_idx(size_t size) if (size <= 192) return size_index[(size - 1) / 8] - 1; - return fls(size - 1) - 1; + return fls(size - 1) - 2; } #define NUM_CACHES 11 diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index dbef0b0967ae..7ee218827259 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3243,13 +3243,24 @@ static bool __is_pointer_value(bool allow_ptr_leaks, return reg->type != SCALAR_VALUE; } +/* Copy src state preserving dst->parent and dst->live fields */ +static void copy_register_state(struct bpf_reg_state *dst, const struct bpf_reg_state *src) +{ + struct bpf_reg_state *parent = dst->parent; + enum bpf_reg_liveness live = dst->live; + + *dst = *src; + dst->parent = parent; + dst->live = live; +} + static void save_register_state(struct bpf_func_state *state, int spi, struct bpf_reg_state *reg, int size) { int i; - state->stack[spi].spilled_ptr = *reg; + copy_register_state(&state->stack[spi].spilled_ptr, reg); if (size == BPF_REG_SIZE) state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN; @@ -3577,7 +3588,7 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, */ s32 subreg_def = state->regs[dst_regno].subreg_def; - state->regs[dst_regno] = *reg; + copy_register_state(&state->regs[dst_regno], reg); state->regs[dst_regno].subreg_def = subreg_def; } else { for (i = 0; i < size; i++) { @@ -3598,7 +3609,7 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, if (dst_regno >= 0) { /* restore register state from stack */ - state->regs[dst_regno] = *reg; + copy_register_state(&state->regs[dst_regno], reg); /* mark reg as written since spilled pointer state likely * has its liveness marks cleared by is_state_visited() * which resets stack/reg liveness for state transitions @@ -9592,7 +9603,7 @@ do_sim: */ if (!ptr_is_dst_reg) { tmp = *dst_reg; - *dst_reg = *ptr_reg; + copy_register_state(dst_reg, ptr_reg); } ret = sanitize_speculative_path(env, NULL, env->insn_idx + 1, env->insn_idx); @@ -10845,7 +10856,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) * to propagate min/max range. */ src_reg->id = ++env->id_gen; - *dst_reg = *src_reg; + copy_register_state(dst_reg, src_reg); dst_reg->live |= REG_LIVE_WRITTEN; dst_reg->subreg_def = DEF_NOT_SUBREG; } else { @@ -10856,7 +10867,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) insn->src_reg); return -EACCES; } else if (src_reg->type == SCALAR_VALUE) { - *dst_reg = *src_reg; + copy_register_state(dst_reg, src_reg); /* Make sure ID is cleared otherwise * dst_reg min/max could be incorrectly * propagated into src_reg by find_equal_scalars() @@ -11655,7 +11666,7 @@ static void find_equal_scalars(struct bpf_verifier_state *vstate, bpf_for_each_reg_in_vstate(vstate, state, reg, ({ if (reg->type == SCALAR_VALUE && reg->id == known_reg->id) - *reg = *known_reg; + copy_register_state(reg, known_reg); })); } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index f47274de012b..c09792c551bf 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -833,6 +833,7 @@ static void do_bpf_send_signal(struct irq_work *entry) work = container_of(entry, struct send_signal_irq_work, irq_work); group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type); + put_task_struct(work->task); } static int bpf_send_signal_common(u32 sig, enum pid_type type) @@ -867,7 +868,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type) * to the irq_work. The current task may change when queued * irq works get executed. */ - work->task = current; + work->task = get_task_struct(current); work->sig = sig; work->type = type; irq_work_queue(&work->irq_work); diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 22fa2c5bc6ec..a68a7290a3b2 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -1569,15 +1569,16 @@ void sock_map_unhash(struct sock *sk) psock = sk_psock(sk); if (unlikely(!psock)) { rcu_read_unlock(); - if (sk->sk_prot->unhash) - sk->sk_prot->unhash(sk); - return; + saved_unhash = READ_ONCE(sk->sk_prot)->unhash; + } else { + saved_unhash = psock->saved_unhash; + sock_map_remove_links(sk, psock); + rcu_read_unlock(); } - - saved_unhash = psock->saved_unhash; - sock_map_remove_links(sk, psock); - rcu_read_unlock(); - saved_unhash(sk); + if (WARN_ON_ONCE(saved_unhash == sock_map_unhash)) + return; + if (saved_unhash) + saved_unhash(sk); } EXPORT_SYMBOL_GPL(sock_map_unhash); @@ -1590,17 +1591,18 @@ void sock_map_destroy(struct sock *sk) psock = sk_psock_get(sk); if (unlikely(!psock)) { rcu_read_unlock(); - if (sk->sk_prot->destroy) - sk->sk_prot->destroy(sk); - return; + saved_destroy = READ_ONCE(sk->sk_prot)->destroy; + } else { + saved_destroy = psock->saved_destroy; + sock_map_remove_links(sk, psock); + rcu_read_unlock(); + sk_psock_stop(psock); + sk_psock_put(sk, psock); } - - saved_destroy = psock->saved_destroy; - sock_map_remove_links(sk, psock); - rcu_read_unlock(); - sk_psock_stop(psock); - sk_psock_put(sk, psock); - saved_destroy(sk); + if (WARN_ON_ONCE(saved_destroy == sock_map_destroy)) + return; + if (saved_destroy) + saved_destroy(sk); } EXPORT_SYMBOL_GPL(sock_map_destroy); @@ -1615,16 +1617,21 @@ void sock_map_close(struct sock *sk, long timeout) if (unlikely(!psock)) { rcu_read_unlock(); release_sock(sk); - return sk->sk_prot->close(sk, timeout); + saved_close = READ_ONCE(sk->sk_prot)->close; + } else { + saved_close = psock->saved_close; + sock_map_remove_links(sk, psock); + rcu_read_unlock(); + sk_psock_stop(psock); + release_sock(sk); + cancel_work_sync(&psock->work); + sk_psock_put(sk, psock); } - - saved_close = psock->saved_close; - sock_map_remove_links(sk, psock); - rcu_read_unlock(); - sk_psock_stop(psock); - release_sock(sk); - cancel_work_sync(&psock->work); - sk_psock_put(sk, psock); + /* Make sure we do not recurse. This is a bug. + * Leak the socket instead of crashing on a stack overflow. + */ + if (WARN_ON_ONCE(saved_close == sock_map_close)) + return; saved_close(sk, timeout); } EXPORT_SYMBOL_GPL(sock_map_close); diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index 94aad3870c5f..cf26d65ca389 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -6,6 +6,7 @@ #include <linux/bpf.h> #include <linux/init.h> #include <linux/wait.h> +#include <linux/util_macros.h> #include <net/inet_common.h> #include <net/tls.h> @@ -639,10 +640,9 @@ EXPORT_SYMBOL_GPL(tcp_bpf_update_proto); */ void tcp_bpf_clone(const struct sock *sk, struct sock *newsk) { - int family = sk->sk_family == AF_INET6 ? TCP_BPF_IPV6 : TCP_BPF_IPV4; struct proto *prot = newsk->sk_prot; - if (prot == &tcp_bpf_prots[family][TCP_BPF_BASE]) + if (is_insidevar(prot, tcp_bpf_prots)) newsk->sk_prot = sk->sk_prot_creator; } #endif /* CONFIG_BPF_SYSCALL */ diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c index 2cf0c7a3fe23..567e07c19ecc 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c @@ -30,6 +30,8 @@ #define MAX_STRERR_LEN 256 #define MAX_TEST_NAME 80 +#define __always_unused __attribute__((__unused__)) + #define _FAIL(errnum, fmt...) \ ({ \ error_at_line(0, (errnum), __func__, __LINE__, fmt); \ @@ -321,7 +323,8 @@ static int socket_loopback(int family, int sotype) return socket_loopback_reuseport(family, sotype, -1); } -static void test_insert_invalid(int family, int sotype, int mapfd) +static void test_insert_invalid(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { u32 key = 0; u64 value; @@ -338,7 +341,8 @@ static void test_insert_invalid(int family, int sotype, int mapfd) FAIL_ERRNO("map_update: expected EBADF"); } -static void test_insert_opened(int family, int sotype, int mapfd) +static void test_insert_opened(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { u32 key = 0; u64 value; @@ -359,7 +363,8 @@ static void test_insert_opened(int family, int sotype, int mapfd) xclose(s); } -static void test_insert_bound(int family, int sotype, int mapfd) +static void test_insert_bound(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { struct sockaddr_storage addr; socklen_t len; @@ -386,7 +391,8 @@ close: xclose(s); } -static void test_insert(int family, int sotype, int mapfd) +static void test_insert(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { u64 value; u32 key; @@ -402,7 +408,8 @@ static void test_insert(int family, int sotype, int mapfd) xclose(s); } -static void test_delete_after_insert(int family, int sotype, int mapfd) +static void test_delete_after_insert(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { u64 value; u32 key; @@ -419,7 +426,8 @@ static void test_delete_after_insert(int family, int sotype, int mapfd) xclose(s); } -static void test_delete_after_close(int family, int sotype, int mapfd) +static void test_delete_after_close(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { int err, s; u64 value; @@ -442,7 +450,8 @@ static void test_delete_after_close(int family, int sotype, int mapfd) FAIL_ERRNO("map_delete: expected EINVAL/EINVAL"); } -static void test_lookup_after_insert(int family, int sotype, int mapfd) +static void test_lookup_after_insert(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { u64 cookie, value; socklen_t len; @@ -470,7 +479,8 @@ static void test_lookup_after_insert(int family, int sotype, int mapfd) xclose(s); } -static void test_lookup_after_delete(int family, int sotype, int mapfd) +static void test_lookup_after_delete(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { int err, s; u64 value; @@ -493,7 +503,8 @@ static void test_lookup_after_delete(int family, int sotype, int mapfd) xclose(s); } -static void test_lookup_32_bit_value(int family, int sotype, int mapfd) +static void test_lookup_32_bit_value(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { u32 key, value32; int err, s; @@ -523,7 +534,8 @@ close: xclose(s); } -static void test_update_existing(int family, int sotype, int mapfd) +static void test_update_existing(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { int s1, s2; u64 value; @@ -551,7 +563,7 @@ close_s1: /* Exercise the code path where we destroy child sockets that never * got accept()'ed, aka orphans, when parent socket gets closed. */ -static void test_destroy_orphan_child(int family, int sotype, int mapfd) +static void do_destroy_orphan_child(int family, int sotype, int mapfd) { struct sockaddr_storage addr; socklen_t len; @@ -582,10 +594,38 @@ close_srv: xclose(s); } +static void test_destroy_orphan_child(struct test_sockmap_listen *skel, + int family, int sotype, int mapfd) +{ + int msg_verdict = bpf_program__fd(skel->progs.prog_msg_verdict); + int skb_verdict = bpf_program__fd(skel->progs.prog_skb_verdict); + const struct test { + int progfd; + enum bpf_attach_type atype; + } tests[] = { + { -1, -1 }, + { msg_verdict, BPF_SK_MSG_VERDICT }, + { skb_verdict, BPF_SK_SKB_VERDICT }, + }; + const struct test *t; + + for (t = tests; t < tests + ARRAY_SIZE(tests); t++) { + if (t->progfd != -1 && + xbpf_prog_attach(t->progfd, mapfd, t->atype, 0) != 0) + return; + + do_destroy_orphan_child(family, sotype, mapfd); + + if (t->progfd != -1) + xbpf_prog_detach2(t->progfd, mapfd, t->atype); + } +} + /* Perform a passive open after removing listening socket from SOCKMAP * to ensure that callbacks get restored properly. */ -static void test_clone_after_delete(int family, int sotype, int mapfd) +static void test_clone_after_delete(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { struct sockaddr_storage addr; socklen_t len; @@ -621,7 +661,8 @@ close_srv: * SOCKMAP, but got accept()'ed only after the parent has been removed * from SOCKMAP, gets cloned without parent psock state or callbacks. */ -static void test_accept_after_delete(int family, int sotype, int mapfd) +static void test_accept_after_delete(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { struct sockaddr_storage addr; const u32 zero = 0; @@ -675,7 +716,8 @@ close_srv: /* Check that child socket that got created and accepted while parent * was in a SOCKMAP is cloned without parent psock state or callbacks. */ -static void test_accept_before_delete(int family, int sotype, int mapfd) +static void test_accept_before_delete(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { struct sockaddr_storage addr; const u32 zero = 0, one = 1; @@ -784,7 +826,8 @@ done: return NULL; } -static void test_syn_recv_insert_delete(int family, int sotype, int mapfd) +static void test_syn_recv_insert_delete(struct test_sockmap_listen *skel __always_unused, + int family, int sotype, int mapfd) { struct connect_accept_ctx ctx = { 0 }; struct sockaddr_storage addr; @@ -847,7 +890,8 @@ static void *listen_thread(void *arg) return NULL; } -static void test_race_insert_listen(int family, int socktype, int mapfd) +static void test_race_insert_listen(struct test_sockmap_listen *skel __always_unused, + int family, int socktype, int mapfd) { struct connect_accept_ctx ctx = { 0 }; const u32 zero = 0; @@ -1473,7 +1517,8 @@ static void test_ops(struct test_sockmap_listen *skel, struct bpf_map *map, int family, int sotype) { const struct op_test { - void (*fn)(int family, int sotype, int mapfd); + void (*fn)(struct test_sockmap_listen *skel, + int family, int sotype, int mapfd); const char *name; int sotype; } tests[] = { @@ -1520,7 +1565,7 @@ static void test_ops(struct test_sockmap_listen *skel, struct bpf_map *map, if (!test__start_subtest(s)) continue; - t->fn(family, sotype, map_fd); + t->fn(skel, family, sotype, map_fd); test_ops_cleanup(map); } } diff --git a/tools/testing/selftests/bpf/verifier/search_pruning.c b/tools/testing/selftests/bpf/verifier/search_pruning.c index 68b14fdfebdb..d63fd8991b03 100644 --- a/tools/testing/selftests/bpf/verifier/search_pruning.c +++ b/tools/testing/selftests/bpf/verifier/search_pruning.c @@ -225,3 +225,39 @@ .result_unpriv = ACCEPT, .insn_processed = 15, }, +/* The test performs a conditional 64-bit write to a stack location + * fp[-8], this is followed by an unconditional 8-bit write to fp[-8], + * then data is read from fp[-8]. This sequence is unsafe. + * + * The test would be mistakenly marked as safe w/o dst register parent + * preservation in verifier.c:copy_register_state() function. + * + * Note the usage of BPF_F_TEST_STATE_FREQ to force creation of the + * checkpoint state after conditional 64-bit assignment. + */ +{ + "write tracking and register parent chain bug", + .insns = { + /* r6 = ktime_get_ns() */ + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_MOV64_REG(BPF_REG_6, BPF_REG_0), + /* r0 = ktime_get_ns() */ + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + /* if r0 > r6 goto +1 */ + BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_6, 1), + /* *(u64 *)(r10 - 8) = 0xdeadbeef */ + BPF_ST_MEM(BPF_DW, BPF_REG_FP, -8, 0xdeadbeef), + /* r1 = 42 */ + BPF_MOV64_IMM(BPF_REG_1, 42), + /* *(u8 *)(r10 - 8) = r1 */ + BPF_STX_MEM(BPF_B, BPF_REG_FP, BPF_REG_1, -8), + /* r2 = *(u64 *)(r10 - 8) */ + BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_FP, -8), + /* exit(0) */ + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .flags = BPF_F_TEST_STATE_FREQ, + .errstr = "invalid read from stack off -8+1 size 8", + .result = REJECT, +}, |