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-rw-r--r--include/linux/filter.h2
-rw-r--r--include/net/tcp.h5
-rw-r--r--kernel/bpf/devmap.c3
-rw-r--r--kernel/bpf/sockmap.c28
-rw-r--r--net/core/filter.c31
-rw-r--r--samples/sockmap/sockmap_kern.c2
-rw-r--r--tools/include/uapi/linux/bpf.h3
-rw-r--r--tools/testing/selftests/bpf/bpf_helpers.h2
-rw-r--r--tools/testing/selftests/bpf/sockmap_verdict_prog.c4
-rw-r--r--tools/testing/selftests/bpf/test_maps.c12
-rw-r--r--tools/testing/selftests/bpf/test_verifier.c16
11 files changed, 74 insertions, 34 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h
index d29e58fde364..818a0b26249e 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -728,7 +728,7 @@ void xdp_do_flush_map(void);
void bpf_warn_invalid_xdp_action(u32 act);
void bpf_warn_invalid_xdp_redirect(u32 ifindex);
-struct sock *do_sk_redirect_map(void);
+struct sock *do_sk_redirect_map(struct sk_buff *skb);
#ifdef CONFIG_BPF_JIT
extern int bpf_jit_enable;
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 89974c5286d8..b1ef98ebce53 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -840,6 +840,11 @@ struct tcp_skb_cb {
struct inet6_skb_parm h6;
#endif
} header; /* For incoming skbs */
+ struct {
+ __u32 key;
+ __u32 flags;
+ struct bpf_map *map;
+ } bpf;
};
};
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 920428d84da2..52e0548ba548 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -78,6 +78,9 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
int err = -EINVAL;
u64 cost;
+ if (!capable(CAP_NET_ADMIN))
+ return ERR_PTR(-EPERM);
+
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
attr->value_size != 4 || attr->map_flags & ~BPF_F_NUMA_NODE)
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c
index 6424ce0e4969..2b6eb35ae5d3 100644
--- a/kernel/bpf/sockmap.c
+++ b/kernel/bpf/sockmap.c
@@ -39,6 +39,7 @@
#include <linux/workqueue.h>
#include <linux/list.h>
#include <net/strparser.h>
+#include <net/tcp.h>
struct bpf_stab {
struct bpf_map map;
@@ -101,9 +102,16 @@ static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb)
return SK_DROP;
skb_orphan(skb);
+ /* We need to ensure that BPF metadata for maps is also cleared
+ * when we orphan the skb so that we don't have the possibility
+ * to reference a stale map.
+ */
+ TCP_SKB_CB(skb)->bpf.map = NULL;
skb->sk = psock->sock;
bpf_compute_data_end(skb);
+ preempt_disable();
rc = (*prog->bpf_func)(skb, prog->insnsi);
+ preempt_enable();
skb->sk = NULL;
return rc;
@@ -114,17 +122,10 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
struct sock *sk;
int rc;
- /* Because we use per cpu values to feed input from sock redirect
- * in BPF program to do_sk_redirect_map() call we need to ensure we
- * are not preempted. RCU read lock is not sufficient in this case
- * with CONFIG_PREEMPT_RCU enabled so we must be explicit here.
- */
- preempt_disable();
rc = smap_verdict_func(psock, skb);
switch (rc) {
case SK_REDIRECT:
- sk = do_sk_redirect_map();
- preempt_enable();
+ sk = do_sk_redirect_map(skb);
if (likely(sk)) {
struct smap_psock *peer = smap_psock_sk(sk);
@@ -141,8 +142,6 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
/* Fall through and free skb otherwise */
case SK_DROP:
default:
- if (rc != SK_REDIRECT)
- preempt_enable();
kfree_skb(skb);
}
}
@@ -487,6 +486,9 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
int err = -EINVAL;
u64 cost;
+ if (!capable(CAP_NET_ADMIN))
+ return ERR_PTR(-EPERM);
+
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
attr->value_size != 4 || attr->map_flags & ~BPF_F_NUMA_NODE)
@@ -840,6 +842,12 @@ static int sock_map_update_elem(struct bpf_map *map,
return -EINVAL;
}
+ if (skops.sk->sk_type != SOCK_STREAM ||
+ skops.sk->sk_protocol != IPPROTO_TCP) {
+ fput(socket->file);
+ return -EOPNOTSUPP;
+ }
+
err = sock_map_ctx_update_elem(&skops, map, key, flags);
fput(socket->file);
return err;
diff --git a/net/core/filter.c b/net/core/filter.c
index 74b8c91fb5f4..aa0265997f93 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1839,31 +1839,31 @@ static const struct bpf_func_proto bpf_redirect_proto = {
.arg2_type = ARG_ANYTHING,
};
-BPF_CALL_3(bpf_sk_redirect_map, struct bpf_map *, map, u32, key, u64, flags)
+BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
+ struct bpf_map *, map, u32, key, u64, flags)
{
- struct redirect_info *ri = this_cpu_ptr(&redirect_info);
+ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
if (unlikely(flags))
return SK_ABORTED;
- ri->ifindex = key;
- ri->flags = flags;
- ri->map = map;
+ tcb->bpf.key = key;
+ tcb->bpf.flags = flags;
+ tcb->bpf.map = map;
return SK_REDIRECT;
}
-struct sock *do_sk_redirect_map(void)
+struct sock *do_sk_redirect_map(struct sk_buff *skb)
{
- struct redirect_info *ri = this_cpu_ptr(&redirect_info);
+ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
struct sock *sk = NULL;
- if (ri->map) {
- sk = __sock_map_lookup_elem(ri->map, ri->ifindex);
+ if (tcb->bpf.map) {
+ sk = __sock_map_lookup_elem(tcb->bpf.map, tcb->bpf.key);
- ri->ifindex = 0;
- ri->map = NULL;
- /* we do not clear flags for future lookup */
+ tcb->bpf.key = 0;
+ tcb->bpf.map = NULL;
}
return sk;
@@ -1873,9 +1873,10 @@ static const struct bpf_func_proto bpf_sk_redirect_map_proto = {
.func = bpf_sk_redirect_map,
.gpl_only = false,
.ret_type = RET_INTEGER,
- .arg1_type = ARG_CONST_MAP_PTR,
- .arg2_type = ARG_ANYTHING,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_ANYTHING,
};
BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
@@ -3683,7 +3684,6 @@ static bool sk_skb_is_valid_access(int off, int size,
{
if (type == BPF_WRITE) {
switch (off) {
- case bpf_ctx_range(struct __sk_buff, mark):
case bpf_ctx_range(struct __sk_buff, tc_index):
case bpf_ctx_range(struct __sk_buff, priority):
break;
@@ -3693,6 +3693,7 @@ static bool sk_skb_is_valid_access(int off, int size,
}
switch (off) {
+ case bpf_ctx_range(struct __sk_buff, mark):
case bpf_ctx_range(struct __sk_buff, tc_classid):
return false;
case bpf_ctx_range(struct __sk_buff, data):
diff --git a/samples/sockmap/sockmap_kern.c b/samples/sockmap/sockmap_kern.c
index f9b38ef82dc2..52b0053274f4 100644
--- a/samples/sockmap/sockmap_kern.c
+++ b/samples/sockmap/sockmap_kern.c
@@ -62,7 +62,7 @@ int bpf_prog2(struct __sk_buff *skb)
ret = 1;
bpf_printk("sockmap: %d -> %d @ %d\n", lport, bpf_ntohl(rport), ret);
- return bpf_sk_redirect_map(&sock_map, ret, 0);
+ return bpf_sk_redirect_map(skb, &sock_map, ret, 0);
}
SEC("sockops")
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 43ab5c402f98..be9a631a69f7 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -569,9 +569,10 @@ union bpf_attr {
* @flags: reserved for future use
* Return: 0 on success or negative error code
*
- * int bpf_sk_redirect_map(map, key, flags)
+ * int bpf_sk_redirect_map(skb, map, key, flags)
* Redirect skb to a sock in map using key as a lookup key for the
* sock in map.
+ * @skb: pointer to skb
* @map: pointer to sockmap
* @key: key to lookup sock in map
* @flags: reserved for future use
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 36fb9161b34a..b2e02bdcd098 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -65,7 +65,7 @@ static int (*bpf_xdp_adjust_head)(void *ctx, int offset) =
static int (*bpf_setsockopt)(void *ctx, int level, int optname, void *optval,
int optlen) =
(void *) BPF_FUNC_setsockopt;
-static int (*bpf_sk_redirect_map)(void *map, int key, int flags) =
+static int (*bpf_sk_redirect_map)(void *ctx, void *map, int key, int flags) =
(void *) BPF_FUNC_sk_redirect_map;
static int (*bpf_sock_map_update)(void *map, void *key, void *value,
unsigned long long flags) =
diff --git a/tools/testing/selftests/bpf/sockmap_verdict_prog.c b/tools/testing/selftests/bpf/sockmap_verdict_prog.c
index 9b99bd10807d..2cd2d552938b 100644
--- a/tools/testing/selftests/bpf/sockmap_verdict_prog.c
+++ b/tools/testing/selftests/bpf/sockmap_verdict_prog.c
@@ -61,8 +61,8 @@ int bpf_prog2(struct __sk_buff *skb)
bpf_printk("verdict: data[0] = redir(%u:%u)\n", map, sk);
if (!map)
- return bpf_sk_redirect_map(&sock_map_rx, sk, 0);
- return bpf_sk_redirect_map(&sock_map_tx, sk, 0);
+ return bpf_sk_redirect_map(skb, &sock_map_rx, sk, 0);
+ return bpf_sk_redirect_map(skb, &sock_map_tx, sk, 0);
}
char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index fe3a443a1102..50ce52d2013d 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -466,7 +466,7 @@ static void test_sockmap(int tasks, void *data)
int one = 1, map_fd_rx, map_fd_tx, map_fd_break, s, sc, rc;
struct bpf_map *bpf_map_rx, *bpf_map_tx, *bpf_map_break;
int ports[] = {50200, 50201, 50202, 50204};
- int err, i, fd, sfd[6] = {0xdeadbeef};
+ int err, i, fd, udp, sfd[6] = {0xdeadbeef};
u8 buf[20] = {0x0, 0x5, 0x3, 0x2, 0x1, 0x0};
int parse_prog, verdict_prog;
struct sockaddr_in addr;
@@ -548,6 +548,16 @@ static void test_sockmap(int tasks, void *data)
goto out_sockmap;
}
+ /* Test update with unsupported UDP socket */
+ udp = socket(AF_INET, SOCK_DGRAM, 0);
+ i = 0;
+ err = bpf_map_update_elem(fd, &i, &udp, BPF_ANY);
+ if (!err) {
+ printf("Failed socket SOCK_DGRAM allowed '%i:%i'\n",
+ i, udp);
+ goto out_sockmap;
+ }
+
/* Test update without programs */
for (i = 0; i < 6; i++) {
err = bpf_map_update_elem(fd, &i, &sfd[i], BPF_ANY);
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 3c7d3a45a3c5..50e15cedbb7f 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -1130,15 +1130,27 @@ static struct bpf_test tests[] = {
.errstr = "invalid bpf_context access",
},
{
- "check skb->mark is writeable by SK_SKB",
+ "invalid access of skb->mark for SK_SKB",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, mark)),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_SK_SKB,
+ .errstr = "invalid bpf_context access",
+ },
+ {
+ "check skb->mark is not writeable by SK_SKB",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
- .result = ACCEPT,
+ .result = REJECT,
.prog_type = BPF_PROG_TYPE_SK_SKB,
+ .errstr = "invalid bpf_context access",
},
{
"check skb->tc_index is writeable by SK_SKB",
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-05 15:44:52 +0000