diff options
author | David S. Miller <davem@davemloft.net> | 2017-09-08 21:11:01 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2017-09-08 21:11:01 -0700 |
commit | a7bc57749f231dcd5fdbc7b653bc260064caf0b9 (patch) | |
tree | 0925d65fb3e7e0eec9f6d08f22086a861d294dac | |
parent | 109980b894e9dae66c37c3d804a415aa68b19c7e (diff) | |
parent | 374fb014fc5b15e420faa00af036868a635eadd3 (diff) |
Merge branch 'xdp-bpf-fixes'
John Fastabend says:
====================
net: Fixes for XDP/BPF
The following fixes, UAPI updates, and small improvement,
i. XDP needs to be called inside RCU with preempt disabled.
ii. Not strictly a bug fix but we have an attach command in the
sockmap UAPI already to avoid having a single kernel released with
only the attach and not the detach I'm pushing this into net branch.
Its early in the RC cycle so I think this is OK (not ideal but better
than supporting a UAPI with a missing detach forever).
iii. Final patch replace cpu_relax with cond_resched in devmap.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | include/linux/bpf.h | 8 | ||||
-rw-r--r-- | kernel/bpf/devmap.c | 2 | ||||
-rw-r--r-- | kernel/bpf/sockmap.c | 2 | ||||
-rw-r--r-- | kernel/bpf/syscall.c | 27 | ||||
-rw-r--r-- | net/core/dev.c | 25 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/test_maps.c | 51 |
6 files changed, 89 insertions, 26 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c2cb1b5c094e..8390859e79e7 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -385,16 +385,16 @@ static inline void __dev_map_flush(struct bpf_map *map) #if defined(CONFIG_STREAM_PARSER) && defined(CONFIG_BPF_SYSCALL) struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key); -int sock_map_attach_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type); +int sock_map_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type); #else static inline struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key) { return NULL; } -static inline int sock_map_attach_prog(struct bpf_map *map, - struct bpf_prog *prog, - u32 type) +static inline int sock_map_prog(struct bpf_map *map, + struct bpf_prog *prog, + u32 type) { return -EOPNOTSUPP; } diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index ecf9f99ecc57..959c9a07f318 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -159,7 +159,7 @@ static void dev_map_free(struct bpf_map *map) unsigned long *bitmap = per_cpu_ptr(dtab->flush_needed, cpu); while (!bitmap_empty(bitmap, dtab->map.max_entries)) - cpu_relax(); + cond_resched(); } for (i = 0; i < dtab->map.max_entries; i++) { diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index f6ffde9c6a68..6424ce0e4969 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -792,7 +792,7 @@ out_progs: return err; } -int sock_map_attach_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type) +int sock_map_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type) { struct bpf_stab *stab = container_of(map, struct bpf_stab, map); struct bpf_prog *orig; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 70ad8e220343..cb17e1cd1d43 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1096,10 +1096,10 @@ static int bpf_obj_get(const union bpf_attr *attr) #define BPF_PROG_ATTACH_LAST_FIELD attach_flags -static int sockmap_get_from_fd(const union bpf_attr *attr) +static int sockmap_get_from_fd(const union bpf_attr *attr, bool attach) { + struct bpf_prog *prog = NULL; int ufd = attr->target_fd; - struct bpf_prog *prog; struct bpf_map *map; struct fd f; int err; @@ -1109,16 +1109,20 @@ static int sockmap_get_from_fd(const union bpf_attr *attr) if (IS_ERR(map)) return PTR_ERR(map); - prog = bpf_prog_get_type(attr->attach_bpf_fd, BPF_PROG_TYPE_SK_SKB); - if (IS_ERR(prog)) { - fdput(f); - return PTR_ERR(prog); + if (attach) { + prog = bpf_prog_get_type(attr->attach_bpf_fd, + BPF_PROG_TYPE_SK_SKB); + if (IS_ERR(prog)) { + fdput(f); + return PTR_ERR(prog); + } } - err = sock_map_attach_prog(map, prog, attr->attach_type); + err = sock_map_prog(map, prog, attr->attach_type); if (err) { fdput(f); - bpf_prog_put(prog); + if (prog) + bpf_prog_put(prog); return err; } @@ -1155,7 +1159,7 @@ static int bpf_prog_attach(const union bpf_attr *attr) break; case BPF_SK_SKB_STREAM_PARSER: case BPF_SK_SKB_STREAM_VERDICT: - return sockmap_get_from_fd(attr); + return sockmap_get_from_fd(attr, true); default: return -EINVAL; } @@ -1204,7 +1208,10 @@ static int bpf_prog_detach(const union bpf_attr *attr) ret = cgroup_bpf_update(cgrp, NULL, attr->attach_type, false); cgroup_put(cgrp); break; - + case BPF_SK_SKB_STREAM_PARSER: + case BPF_SK_SKB_STREAM_VERDICT: + ret = sockmap_get_from_fd(attr, false); + break; default: return -EINVAL; } diff --git a/net/core/dev.c b/net/core/dev.c index 6f845e4fec17..fb766d906148 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3981,8 +3981,13 @@ static int netif_rx_internal(struct sk_buff *skb) trace_netif_rx(skb); if (static_key_false(&generic_xdp_needed)) { - int ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), - skb); + int ret; + + preempt_disable(); + rcu_read_lock(); + ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); + rcu_read_unlock(); + preempt_enable(); /* Consider XDP consuming the packet a success from * the netdev point of view we do not want to count @@ -4500,18 +4505,20 @@ static int netif_receive_skb_internal(struct sk_buff *skb) if (skb_defer_rx_timestamp(skb)) return NET_RX_SUCCESS; - rcu_read_lock(); - if (static_key_false(&generic_xdp_needed)) { - int ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), - skb); + int ret; - if (ret != XDP_PASS) { - rcu_read_unlock(); + preempt_disable(); + rcu_read_lock(); + ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); + rcu_read_unlock(); + preempt_enable(); + + if (ret != XDP_PASS) return NET_RX_DROP; - } } + rcu_read_lock(); #ifdef CONFIG_RPS if (static_key_false(&rps_needed)) { struct rps_dev_flow voidflow, *rflow = &voidflow; diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index 4acc772a28c0..fe3a443a1102 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -558,7 +558,7 @@ static void test_sockmap(int tasks, void *data) } } - /* Test attaching bad fds */ + /* Test attaching/detaching bad fds */ err = bpf_prog_attach(-1, fd, BPF_SK_SKB_STREAM_PARSER, 0); if (!err) { printf("Failed invalid parser prog attach\n"); @@ -571,6 +571,30 @@ static void test_sockmap(int tasks, void *data) goto out_sockmap; } + err = bpf_prog_attach(-1, fd, __MAX_BPF_ATTACH_TYPE, 0); + if (!err) { + printf("Failed unknown prog attach\n"); + goto out_sockmap; + } + + err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_PARSER); + if (err) { + printf("Failed empty parser prog detach\n"); + goto out_sockmap; + } + + err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_VERDICT); + if (err) { + printf("Failed empty verdict prog detach\n"); + goto out_sockmap; + } + + err = bpf_prog_detach(fd, __MAX_BPF_ATTACH_TYPE); + if (!err) { + printf("Detach invalid prog successful\n"); + goto out_sockmap; + } + /* Load SK_SKB program and Attach */ err = bpf_prog_load(SOCKMAP_PARSE_PROG, BPF_PROG_TYPE_SK_SKB, &obj, &parse_prog); @@ -643,6 +667,13 @@ static void test_sockmap(int tasks, void *data) goto out_sockmap; } + err = bpf_prog_attach(verdict_prog, map_fd_rx, + __MAX_BPF_ATTACH_TYPE, 0); + if (!err) { + printf("Attached unknown bpf prog\n"); + goto out_sockmap; + } + /* Test map update elem afterwards fd lives in fd and map_fd */ for (i = 0; i < 6; i++) { err = bpf_map_update_elem(map_fd_rx, &i, &sfd[i], BPF_ANY); @@ -809,6 +840,24 @@ static void test_sockmap(int tasks, void *data) assert(status == 0); } + err = bpf_prog_detach(map_fd_rx, __MAX_BPF_ATTACH_TYPE); + if (!err) { + printf("Detached an invalid prog type.\n"); + goto out_sockmap; + } + + err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_PARSER); + if (err) { + printf("Failed parser prog detach\n"); + goto out_sockmap; + } + + err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_VERDICT); + if (err) { + printf("Failed parser prog detach\n"); + goto out_sockmap; + } + /* Test map close sockets */ for (i = 0; i < 6; i++) close(sfd[i]); |