From 0df6d32842b9a5f97a29ea90c8adc5cfac38341d Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Tue, 25 Feb 2020 15:04:15 -0800 Subject: inet_diag: Move the INET_DIAG_REQ_BYTECODE nlattr to cb->data The INET_DIAG_REQ_BYTECODE nlattr is currently re-found every time when the "dump()" is re-started. In a latter patch, it will also need to parse the new INET_DIAG_REQ_SK_BPF_STORAGES nlattr to learn the map_fds. Thus, this patch takes this chance to store the parsed nlattr in cb->data during the "start" time of a dump. By doing this, the "bc" argument also becomes unnecessary and is removed. Also, the two copies of the INET_DIAG_REQ_BYTECODE parsing-audit logic between compat/current version can be consolidated to one. Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200225230415.1975555-1-kafai@fb.com --- include/uapi/linux/inet_diag.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index a1ff345b3f33..bab9a9f8da12 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -64,9 +64,10 @@ struct inet_diag_req_raw { enum { INET_DIAG_REQ_NONE, INET_DIAG_REQ_BYTECODE, + __INET_DIAG_REQ_MAX, }; -#define INET_DIAG_REQ_MAX INET_DIAG_REQ_BYTECODE +#define INET_DIAG_REQ_MAX (__INET_DIAG_REQ_MAX - 1) /* Bytecode is sequence of 4 byte commands followed by variable arguments. * All the commands identified by "code" are conditional jumps forward: -- cgit v1.2.3 From 1ed4d92458a969e71e7914550b6f0c730c14d84e Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Tue, 25 Feb 2020 15:04:21 -0800 Subject: bpf: INET_DIAG support in bpf_sk_storage This patch adds INET_DIAG support to bpf_sk_storage. 1. Although this series adds bpf_sk_storage diag capability to inet sk, bpf_sk_storage is in general applicable to all fullsock. Hence, the bpf_sk_storage logic will operate on SK_DIAG_* nlattr. The caller will pass in its specific nesting nlattr (e.g. INET_DIAG_*) as the argument. 2. The request will be like: INET_DIAG_REQ_SK_BPF_STORAGES (nla_nest) (defined in latter patch) SK_DIAG_BPF_STORAGE_REQ_MAP_FD (nla_put_u32) SK_DIAG_BPF_STORAGE_REQ_MAP_FD (nla_put_u32) ...... Considering there could have multiple bpf_sk_storages in a sk, instead of reusing INET_DIAG_INFO ("ss -i"), the user can select some specific bpf_sk_storage to dump by specifying an array of SK_DIAG_BPF_STORAGE_REQ_MAP_FD. If no SK_DIAG_BPF_STORAGE_REQ_MAP_FD is specified (i.e. an empty INET_DIAG_REQ_SK_BPF_STORAGES), it will dump all bpf_sk_storages of a sk. 3. The reply will be like: INET_DIAG_BPF_SK_STORAGES (nla_nest) (defined in latter patch) SK_DIAG_BPF_STORAGE (nla_nest) SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32) SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit) SK_DIAG_BPF_STORAGE (nla_nest) SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32) SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit) ...... 4. Unlike other INET_DIAG info of a sk which is pretty static, the size required to dump the bpf_sk_storage(s) of a sk is dynamic as the system adding more bpf_sk_storage_map. It is hard to set a static min_dump_alloc size. Hence, this series learns it at the runtime and adjust the cb->min_dump_alloc as it iterates all sk(s) of a system. The "unsigned int *res_diag_size" in bpf_sk_storage_diag_put() is for this purpose. The next patch will update the cb->min_dump_alloc as it iterates the sk(s). Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200225230421.1975729-1-kafai@fb.com --- include/uapi/linux/sock_diag.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/sock_diag.h b/include/uapi/linux/sock_diag.h index e5925009a652..5f74a5f6091d 100644 --- a/include/uapi/linux/sock_diag.h +++ b/include/uapi/linux/sock_diag.h @@ -36,4 +36,30 @@ enum sknetlink_groups { }; #define SKNLGRP_MAX (__SKNLGRP_MAX - 1) +enum { + SK_DIAG_BPF_STORAGE_REQ_NONE, + SK_DIAG_BPF_STORAGE_REQ_MAP_FD, + __SK_DIAG_BPF_STORAGE_REQ_MAX, +}; + +#define SK_DIAG_BPF_STORAGE_REQ_MAX (__SK_DIAG_BPF_STORAGE_REQ_MAX - 1) + +enum { + SK_DIAG_BPF_STORAGE_REP_NONE, + SK_DIAG_BPF_STORAGE, + __SK_DIAG_BPF_STORAGE_REP_MAX, +}; + +#define SK_DIAB_BPF_STORAGE_REP_MAX (__SK_DIAG_BPF_STORAGE_REP_MAX - 1) + +enum { + SK_DIAG_BPF_STORAGE_NONE, + SK_DIAG_BPF_STORAGE_PAD, + SK_DIAG_BPF_STORAGE_MAP_ID, + SK_DIAG_BPF_STORAGE_MAP_VALUE, + __SK_DIAG_BPF_STORAGE_MAX, +}; + +#define SK_DIAG_BPF_STORAGE_MAX (__SK_DIAG_BPF_STORAGE_MAX - 1) + #endif /* _UAPI__SOCK_DIAG_H__ */ -- cgit v1.2.3 From 085c20cacf2b72991ce1c9d99a5e2f1d9e73bb68 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Tue, 25 Feb 2020 15:04:27 -0800 Subject: bpf: inet_diag: Dump bpf_sk_storages in inet_diag_dump() This patch will dump out the bpf_sk_storages of a sk if the request has the INET_DIAG_REQ_SK_BPF_STORAGES nlattr. An array of SK_DIAG_BPF_STORAGE_REQ_MAP_FD can be specified in INET_DIAG_REQ_SK_BPF_STORAGES to select which bpf_sk_storage to dump. If no map_fd is specified, all bpf_sk_storages of a sk will be dumped. bpf_sk_storages can be added to the system at runtime. It is difficult to find a proper static value for cb->min_dump_alloc. This patch learns the nlattr size required to dump the bpf_sk_storages of a sk. If it happens to be the very first nlmsg of a dump and it cannot fit the needed bpf_sk_storages, it will try to expand the skb by "pskb_expand_head()". Instead of expanding it in inet_sk_diag_fill(), it is expanded at a sleepable context in __inet_diag_dump() so __GFP_DIRECT_RECLAIM can be used. In __inet_diag_dump(), it will retry as long as the skb is empty and the cb->min_dump_alloc becomes larger than before. cb->min_dump_alloc is bounded by KMALLOC_MAX_SIZE. The min_dump_alloc is also changed from 'u16' to 'u32' to accommodate a sk that may have a few large bpf_sk_storages. The updated cb->min_dump_alloc will also be used to allocate the skb in the next dump. This logic already exists in netlink_dump(). Here is the sample output of a locally modified 'ss' and it could be made more readable by using BTF later: [root@arch-fb-vm1 ~]# ss --bpf-map-id 14 --bpf-map-id 13 -t6an 'dst [::1]:8989' State Recv-Q Send-Q Local Address:Port Peer Address:PortProcess ESTAB 0 0 [::1]:51072 [::1]:8989 bpf_map_id:14 value:[ 3feb ] bpf_map_id:13 value:[ 3f ] ESTAB 0 0 [::1]:51070 [::1]:8989 bpf_map_id:14 value:[ 3feb ] bpf_map_id:13 value:[ 3f ] [root@arch-fb-vm1 ~]# ~/devshare/github/iproute2/misc/ss --bpf-maps -t6an 'dst [::1]:8989' State Recv-Q Send-Q Local Address:Port Peer Address:Port Process ESTAB 0 0 [::1]:51072 [::1]:8989 bpf_map_id:14 value:[ 3feb ] bpf_map_id:13 value:[ 3f ] bpf_map_id:12 value:[ 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000... total:65407 ] ESTAB 0 0 [::1]:51070 [::1]:8989 bpf_map_id:14 value:[ 3feb ] bpf_map_id:13 value:[ 3f ] bpf_map_id:12 value:[ 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000... total:65407 ] Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200225230427.1976129-1-kafai@fb.com --- include/uapi/linux/inet_diag.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h index bab9a9f8da12..75dffd78363a 100644 --- a/include/uapi/linux/inet_diag.h +++ b/include/uapi/linux/inet_diag.h @@ -64,6 +64,7 @@ struct inet_diag_req_raw { enum { INET_DIAG_REQ_NONE, INET_DIAG_REQ_BYTECODE, + INET_DIAG_REQ_SK_BPF_STORAGES, __INET_DIAG_REQ_MAX, }; @@ -155,6 +156,7 @@ enum { INET_DIAG_CLASS_ID, /* request as INET_DIAG_TCLASS */ INET_DIAG_MD5SIG, INET_DIAG_ULP_INFO, + INET_DIAG_SK_BPF_STORAGES, __INET_DIAG_MAX, }; -- cgit v1.2.3