bpf: implement getsockopt and setsockopt hooks
Implement new BPF_PROG_TYPE_CGROUP_SOCKOPT program type and BPF_CGROUP_{G,S}ETSOCKOPT cgroup hooks. BPF_CGROUP_SETSOCKOPT can modify user setsockopt arguments before passing them down to the kernel or bypass kernel completely. BPF_CGROUP_GETSOCKOPT can can inspect/modify getsockopt arguments that kernel returns. Both hooks reuse existing PTR_TO_PACKET{,_END} infrastructure. The buffer memory is pre-allocated (because I don't think there is a precedent for working with __user memory from bpf). This might be slow to do for each {s,g}etsockopt call, that's why I've added __cgroup_bpf_prog_array_is_empty that exits early if there is nothing attached to a cgroup. Note, however, that there is a race between __cgroup_bpf_prog_array_is_empty and BPF_PROG_RUN_ARRAY where cgroup program layout might have changed; this should not be a problem because in general there is a race between multiple calls to {s,g}etsocktop and user adding/removing bpf progs from a cgroup. The return code of the BPF program is handled as follows: * 0: EPERM * 1: success, continue with next BPF program in the cgroup chain v9: * allow overwriting setsockopt arguments (Alexei Starovoitov): * use set_fs (same as kernel_setsockopt) * buffer is always kzalloc'd (no small on-stack buffer) v8: * use s32 for optlen (Andrii Nakryiko) v7: * return only 0 or 1 (Alexei Starovoitov) * always run all progs (Alexei Starovoitov) * use optval=0 as kernel bypass in setsockopt (Alexei Starovoitov) (decided to use optval=-1 instead, optval=0 might be a valid input) * call getsockopt hook after kernel handlers (Alexei Starovoitov) v6: * rework cgroup chaining; stop as soon as bpf program returns 0 or 2; see patch with the documentation for the details * drop Andrii's and Martin's Acked-by (not sure they are comfortable with the new state of things) v5: * skip copy_to_user() and put_user() when ret == 0 (Martin Lau) v4: * don't export bpf_sk_fullsock helper (Martin Lau) * size != sizeof(__u64) for uapi pointers (Martin Lau) * offsetof instead of bpf_ctx_range when checking ctx access (Martin Lau) v3: * typos in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY comments (Andrii Nakryiko) * reverse christmas tree in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY (Andrii Nakryiko) * use __bpf_md_ptr instead of __u32 for optval{,_end} (Martin Lau) * use BPF_FIELD_SIZEOF() for consistency (Martin Lau) * new CG_SOCKOPT_ACCESS macro to wrap repeated parts v2: * moved bpf_sockopt_kern fields around to remove a hole (Martin Lau) * aligned bpf_sockopt_kern->buf to 8 bytes (Martin Lau) * bpf_prog_array_is_empty instead of bpf_prog_array_length (Martin Lau) * added [0,2] return code check to verifier (Martin Lau) * dropped unused buf[64] from the stack (Martin Lau) * use PTR_TO_SOCKET for bpf_sockopt->sk (Martin Lau) * dropped bpf_target_off from ctx rewrites (Martin Lau) * use return code for kernel bypass (Martin Lau & Andrii Nakryiko) Cc: Andrii Nakryiko <andriin@fb.com> Cc: Martin Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
parent
3b1c667e47
commit
0d01da6afc
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@ -124,6 +124,14 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
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loff_t *ppos, void **new_buf,
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enum bpf_attach_type type);
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int __cgroup_bpf_run_filter_setsockopt(struct sock *sock, int *level,
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int *optname, char __user *optval,
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int *optlen, char **kernel_optval);
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int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
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int optname, char __user *optval,
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int __user *optlen, int max_optlen,
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int retval);
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static inline enum bpf_cgroup_storage_type cgroup_storage_type(
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struct bpf_map *map)
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{
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@ -286,6 +294,38 @@ int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
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__ret; \
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})
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#define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
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kernel_optval) \
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({ \
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int __ret = 0; \
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if (cgroup_bpf_enabled) \
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__ret = __cgroup_bpf_run_filter_setsockopt(sock, level, \
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optname, optval, \
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optlen, \
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kernel_optval); \
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__ret; \
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})
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#define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) \
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({ \
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int __ret = 0; \
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if (cgroup_bpf_enabled) \
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get_user(__ret, optlen); \
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__ret; \
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})
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#define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, optlen, \
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max_optlen, retval) \
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({ \
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int __ret = retval; \
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if (cgroup_bpf_enabled) \
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__ret = __cgroup_bpf_run_filter_getsockopt(sock, level, \
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optname, optval, \
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optlen, max_optlen, \
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retval); \
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__ret; \
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})
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int cgroup_bpf_prog_attach(const union bpf_attr *attr,
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enum bpf_prog_type ptype, struct bpf_prog *prog);
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int cgroup_bpf_prog_detach(const union bpf_attr *attr,
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@ -357,6 +397,11 @@ static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
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#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
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#define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
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#define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos,nbuf) ({ 0; })
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#define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) ({ 0; })
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#define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, \
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optlen, max_optlen, retval) ({ retval; })
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#define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
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kernel_optval) ({ 0; })
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#define for_each_cgroup_storage_type(stype) for (; false; )
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@ -518,6 +518,7 @@ struct bpf_prog_array {
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struct bpf_prog_array *bpf_prog_array_alloc(u32 prog_cnt, gfp_t flags);
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void bpf_prog_array_free(struct bpf_prog_array *progs);
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int bpf_prog_array_length(struct bpf_prog_array *progs);
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bool bpf_prog_array_is_empty(struct bpf_prog_array *array);
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int bpf_prog_array_copy_to_user(struct bpf_prog_array *progs,
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__u32 __user *prog_ids, u32 cnt);
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@ -1051,6 +1052,7 @@ extern const struct bpf_func_proto bpf_spin_unlock_proto;
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extern const struct bpf_func_proto bpf_get_local_storage_proto;
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extern const struct bpf_func_proto bpf_strtol_proto;
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extern const struct bpf_func_proto bpf_strtoul_proto;
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extern const struct bpf_func_proto bpf_tcp_sock_proto;
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/* Shared helpers among cBPF and eBPF. */
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void bpf_user_rnd_init_once(void);
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@ -30,6 +30,7 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE, raw_tracepoint_writable)
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#ifdef CONFIG_CGROUP_BPF
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BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_DEVICE, cg_dev)
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BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SYSCTL, cg_sysctl)
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BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SOCKOPT, cg_sockopt)
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#endif
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#ifdef CONFIG_BPF_LIRC_MODE2
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BPF_PROG_TYPE(BPF_PROG_TYPE_LIRC_MODE2, lirc_mode2)
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@ -1199,4 +1199,14 @@ struct bpf_sysctl_kern {
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u64 tmp_reg;
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};
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struct bpf_sockopt_kern {
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struct sock *sk;
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u8 *optval;
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u8 *optval_end;
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s32 level;
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s32 optname;
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s32 optlen;
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s32 retval;
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};
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#endif /* __LINUX_FILTER_H__ */
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@ -170,6 +170,7 @@ enum bpf_prog_type {
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BPF_PROG_TYPE_FLOW_DISSECTOR,
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BPF_PROG_TYPE_CGROUP_SYSCTL,
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BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
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BPF_PROG_TYPE_CGROUP_SOCKOPT,
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};
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enum bpf_attach_type {
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@ -194,6 +195,8 @@ enum bpf_attach_type {
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BPF_CGROUP_SYSCTL,
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BPF_CGROUP_UDP4_RECVMSG,
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BPF_CGROUP_UDP6_RECVMSG,
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BPF_CGROUP_GETSOCKOPT,
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BPF_CGROUP_SETSOCKOPT,
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__MAX_BPF_ATTACH_TYPE
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};
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@ -3541,4 +3544,15 @@ struct bpf_sysctl {
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*/
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};
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struct bpf_sockopt {
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__bpf_md_ptr(struct bpf_sock *, sk);
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__bpf_md_ptr(void *, optval);
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__bpf_md_ptr(void *, optval_end);
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__s32 level;
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__s32 optname;
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__s32 optlen;
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__s32 retval;
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};
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#endif /* _UAPI__LINUX_BPF_H__ */
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@ -15,6 +15,7 @@
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#include <linux/bpf.h>
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#include <linux/bpf-cgroup.h>
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#include <net/sock.h>
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#include <net/bpf_sk_storage.h>
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#include "../cgroup/cgroup-internal.h"
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@ -938,6 +939,188 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
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}
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EXPORT_SYMBOL(__cgroup_bpf_run_filter_sysctl);
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static bool __cgroup_bpf_prog_array_is_empty(struct cgroup *cgrp,
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enum bpf_attach_type attach_type)
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{
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struct bpf_prog_array *prog_array;
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bool empty;
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rcu_read_lock();
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prog_array = rcu_dereference(cgrp->bpf.effective[attach_type]);
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empty = bpf_prog_array_is_empty(prog_array);
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rcu_read_unlock();
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return empty;
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}
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static int sockopt_alloc_buf(struct bpf_sockopt_kern *ctx, int max_optlen)
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{
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if (unlikely(max_optlen > PAGE_SIZE) || max_optlen < 0)
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return -EINVAL;
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ctx->optval = kzalloc(max_optlen, GFP_USER);
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if (!ctx->optval)
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return -ENOMEM;
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ctx->optval_end = ctx->optval + max_optlen;
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ctx->optlen = max_optlen;
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return 0;
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}
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static void sockopt_free_buf(struct bpf_sockopt_kern *ctx)
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{
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kfree(ctx->optval);
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}
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int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
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int *optname, char __user *optval,
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int *optlen, char **kernel_optval)
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{
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struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
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struct bpf_sockopt_kern ctx = {
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.sk = sk,
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.level = *level,
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.optname = *optname,
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};
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int ret;
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/* Opportunistic check to see whether we have any BPF program
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* attached to the hook so we don't waste time allocating
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* memory and locking the socket.
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*/
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if (!cgroup_bpf_enabled ||
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__cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_SETSOCKOPT))
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return 0;
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ret = sockopt_alloc_buf(&ctx, *optlen);
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if (ret)
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return ret;
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if (copy_from_user(ctx.optval, optval, *optlen) != 0) {
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ret = -EFAULT;
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goto out;
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}
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lock_sock(sk);
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ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[BPF_CGROUP_SETSOCKOPT],
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&ctx, BPF_PROG_RUN);
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release_sock(sk);
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if (!ret) {
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ret = -EPERM;
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goto out;
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}
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if (ctx.optlen == -1) {
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/* optlen set to -1, bypass kernel */
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ret = 1;
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} else if (ctx.optlen > *optlen || ctx.optlen < -1) {
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/* optlen is out of bounds */
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ret = -EFAULT;
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} else {
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/* optlen within bounds, run kernel handler */
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ret = 0;
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/* export any potential modifications */
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*level = ctx.level;
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*optname = ctx.optname;
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*optlen = ctx.optlen;
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*kernel_optval = ctx.optval;
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}
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out:
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if (ret)
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sockopt_free_buf(&ctx);
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return ret;
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}
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EXPORT_SYMBOL(__cgroup_bpf_run_filter_setsockopt);
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int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
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int optname, char __user *optval,
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int __user *optlen, int max_optlen,
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int retval)
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{
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struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
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struct bpf_sockopt_kern ctx = {
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.sk = sk,
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.level = level,
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.optname = optname,
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.retval = retval,
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};
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int ret;
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/* Opportunistic check to see whether we have any BPF program
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* attached to the hook so we don't waste time allocating
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* memory and locking the socket.
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*/
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if (!cgroup_bpf_enabled ||
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__cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_GETSOCKOPT))
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return retval;
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ret = sockopt_alloc_buf(&ctx, max_optlen);
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if (ret)
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return ret;
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if (!retval) {
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/* If kernel getsockopt finished successfully,
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* copy whatever was returned to the user back
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* into our temporary buffer. Set optlen to the
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* one that kernel returned as well to let
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* BPF programs inspect the value.
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*/
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if (get_user(ctx.optlen, optlen)) {
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ret = -EFAULT;
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goto out;
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}
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if (ctx.optlen > max_optlen)
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ctx.optlen = max_optlen;
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if (copy_from_user(ctx.optval, optval, ctx.optlen) != 0) {
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ret = -EFAULT;
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goto out;
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}
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}
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lock_sock(sk);
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ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[BPF_CGROUP_GETSOCKOPT],
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&ctx, BPF_PROG_RUN);
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release_sock(sk);
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if (!ret) {
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ret = -EPERM;
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goto out;
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}
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if (ctx.optlen > max_optlen) {
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ret = -EFAULT;
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goto out;
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}
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/* BPF programs only allowed to set retval to 0, not some
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* arbitrary value.
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*/
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if (ctx.retval != 0 && ctx.retval != retval) {
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ret = -EFAULT;
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goto out;
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}
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if (copy_to_user(optval, ctx.optval, ctx.optlen) ||
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put_user(ctx.optlen, optlen)) {
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ret = -EFAULT;
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goto out;
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}
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ret = ctx.retval;
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out:
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sockopt_free_buf(&ctx);
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return ret;
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}
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EXPORT_SYMBOL(__cgroup_bpf_run_filter_getsockopt);
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static ssize_t sysctl_cpy_dir(const struct ctl_dir *dir, char **bufp,
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size_t *lenp)
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{
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@ -1198,3 +1381,153 @@ const struct bpf_verifier_ops cg_sysctl_verifier_ops = {
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const struct bpf_prog_ops cg_sysctl_prog_ops = {
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};
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static const struct bpf_func_proto *
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cg_sockopt_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
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{
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switch (func_id) {
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case BPF_FUNC_sk_storage_get:
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return &bpf_sk_storage_get_proto;
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case BPF_FUNC_sk_storage_delete:
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return &bpf_sk_storage_delete_proto;
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#ifdef CONFIG_INET
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case BPF_FUNC_tcp_sock:
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return &bpf_tcp_sock_proto;
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#endif
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default:
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return cgroup_base_func_proto(func_id, prog);
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}
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}
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static bool cg_sockopt_is_valid_access(int off, int size,
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enum bpf_access_type type,
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const struct bpf_prog *prog,
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struct bpf_insn_access_aux *info)
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{
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const int size_default = sizeof(__u32);
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if (off < 0 || off >= sizeof(struct bpf_sockopt))
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return false;
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if (off % size != 0)
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return false;
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if (type == BPF_WRITE) {
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switch (off) {
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case offsetof(struct bpf_sockopt, retval):
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if (size != size_default)
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return false;
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return prog->expected_attach_type ==
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BPF_CGROUP_GETSOCKOPT;
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case offsetof(struct bpf_sockopt, optname):
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/* fallthrough */
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case offsetof(struct bpf_sockopt, level):
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if (size != size_default)
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return false;
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return prog->expected_attach_type ==
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BPF_CGROUP_SETSOCKOPT;
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case offsetof(struct bpf_sockopt, optlen):
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return size == size_default;
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default:
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return false;
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}
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}
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switch (off) {
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case offsetof(struct bpf_sockopt, sk):
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if (size != sizeof(__u64))
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return false;
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info->reg_type = PTR_TO_SOCKET;
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break;
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case offsetof(struct bpf_sockopt, optval):
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if (size != sizeof(__u64))
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return false;
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info->reg_type = PTR_TO_PACKET;
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break;
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case offsetof(struct bpf_sockopt, optval_end):
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||||
if (size != sizeof(__u64))
|
||||
return false;
|
||||
info->reg_type = PTR_TO_PACKET_END;
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, retval):
|
||||
if (size != size_default)
|
||||
return false;
|
||||
return prog->expected_attach_type == BPF_CGROUP_GETSOCKOPT;
|
||||
default:
|
||||
if (size != size_default)
|
||||
return false;
|
||||
break;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
#define CG_SOCKOPT_ACCESS_FIELD(T, F) \
|
||||
T(BPF_FIELD_SIZEOF(struct bpf_sockopt_kern, F), \
|
||||
si->dst_reg, si->src_reg, \
|
||||
offsetof(struct bpf_sockopt_kern, F))
|
||||
|
||||
static u32 cg_sockopt_convert_ctx_access(enum bpf_access_type type,
|
||||
const struct bpf_insn *si,
|
||||
struct bpf_insn *insn_buf,
|
||||
struct bpf_prog *prog,
|
||||
u32 *target_size)
|
||||
{
|
||||
struct bpf_insn *insn = insn_buf;
|
||||
|
||||
switch (si->off) {
|
||||
case offsetof(struct bpf_sockopt, sk):
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, sk);
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, level):
|
||||
if (type == BPF_WRITE)
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, level);
|
||||
else
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, level);
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, optname):
|
||||
if (type == BPF_WRITE)
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, optname);
|
||||
else
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optname);
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, optlen):
|
||||
if (type == BPF_WRITE)
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, optlen);
|
||||
else
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optlen);
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, retval):
|
||||
if (type == BPF_WRITE)
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, retval);
|
||||
else
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, retval);
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, optval):
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optval);
|
||||
break;
|
||||
case offsetof(struct bpf_sockopt, optval_end):
|
||||
*insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optval_end);
|
||||
break;
|
||||
}
|
||||
|
||||
return insn - insn_buf;
|
||||
}
|
||||
|
||||
static int cg_sockopt_get_prologue(struct bpf_insn *insn_buf,
|
||||
bool direct_write,
|
||||
const struct bpf_prog *prog)
|
||||
{
|
||||
/* Nothing to do for sockopt argument. The data is kzalloc'ated.
|
||||
*/
|
||||
return 0;
|
||||
}
|
||||
|
||||
const struct bpf_verifier_ops cg_sockopt_verifier_ops = {
|
||||
.get_func_proto = cg_sockopt_func_proto,
|
||||
.is_valid_access = cg_sockopt_is_valid_access,
|
||||
.convert_ctx_access = cg_sockopt_convert_ctx_access,
|
||||
.gen_prologue = cg_sockopt_get_prologue,
|
||||
};
|
||||
|
||||
const struct bpf_prog_ops cg_sockopt_prog_ops = {
|
||||
};
|
||||
|
|
|
@ -1809,6 +1809,15 @@ int bpf_prog_array_length(struct bpf_prog_array *array)
|
|||
return cnt;
|
||||
}
|
||||
|
||||
bool bpf_prog_array_is_empty(struct bpf_prog_array *array)
|
||||
{
|
||||
struct bpf_prog_array_item *item;
|
||||
|
||||
for (item = array->items; item->prog; item++)
|
||||
if (item->prog != &dummy_bpf_prog.prog)
|
||||
return false;
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool bpf_prog_array_copy_core(struct bpf_prog_array *array,
|
||||
u32 *prog_ids,
|
||||
|
|
|
@ -1590,6 +1590,14 @@ bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
|
|||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
|
||||
switch (expected_attach_type) {
|
||||
case BPF_CGROUP_SETSOCKOPT:
|
||||
case BPF_CGROUP_GETSOCKOPT:
|
||||
return 0;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
|
@ -1840,6 +1848,7 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
|
|||
switch (prog->type) {
|
||||
case BPF_PROG_TYPE_CGROUP_SOCK:
|
||||
case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
|
||||
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
|
||||
return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
|
||||
case BPF_PROG_TYPE_CGROUP_SKB:
|
||||
return prog->enforce_expected_attach_type &&
|
||||
|
@ -1912,6 +1921,10 @@ static int bpf_prog_attach(const union bpf_attr *attr)
|
|||
case BPF_CGROUP_SYSCTL:
|
||||
ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
|
||||
break;
|
||||
case BPF_CGROUP_GETSOCKOPT:
|
||||
case BPF_CGROUP_SETSOCKOPT:
|
||||
ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
|
||||
break;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
|
@ -1995,6 +2008,10 @@ static int bpf_prog_detach(const union bpf_attr *attr)
|
|||
case BPF_CGROUP_SYSCTL:
|
||||
ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
|
||||
break;
|
||||
case BPF_CGROUP_GETSOCKOPT:
|
||||
case BPF_CGROUP_SETSOCKOPT:
|
||||
ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
|
||||
break;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
|
@ -2031,6 +2048,8 @@ static int bpf_prog_query(const union bpf_attr *attr,
|
|||
case BPF_CGROUP_SOCK_OPS:
|
||||
case BPF_CGROUP_DEVICE:
|
||||
case BPF_CGROUP_SYSCTL:
|
||||
case BPF_CGROUP_GETSOCKOPT:
|
||||
case BPF_CGROUP_SETSOCKOPT:
|
||||
break;
|
||||
case BPF_LIRC_MODE2:
|
||||
return lirc_prog_query(attr, uattr);
|
||||
|
|
|
@ -2215,6 +2215,13 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env,
|
|||
|
||||
env->seen_direct_write = true;
|
||||
return true;
|
||||
|
||||
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
|
||||
if (t == BPF_WRITE)
|
||||
env->seen_direct_write = true;
|
||||
|
||||
return true;
|
||||
|
||||
default:
|
||||
return false;
|
||||
}
|
||||
|
@ -6066,6 +6073,7 @@ static int check_return_code(struct bpf_verifier_env *env)
|
|||
case BPF_PROG_TYPE_SOCK_OPS:
|
||||
case BPF_PROG_TYPE_CGROUP_DEVICE:
|
||||
case BPF_PROG_TYPE_CGROUP_SYSCTL:
|
||||
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
|
||||
break;
|
||||
default:
|
||||
return 0;
|
||||
|
|
|
@ -5651,7 +5651,7 @@ BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
|
|||
return (unsigned long)NULL;
|
||||
}
|
||||
|
||||
static const struct bpf_func_proto bpf_tcp_sock_proto = {
|
||||
const struct bpf_func_proto bpf_tcp_sock_proto = {
|
||||
.func = bpf_tcp_sock,
|
||||
.gpl_only = false,
|
||||
.ret_type = RET_PTR_TO_TCP_SOCK_OR_NULL,
|
||||
|
|
30
net/socket.c
30
net/socket.c
|
@ -2051,6 +2051,8 @@ SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
|
|||
static int __sys_setsockopt(int fd, int level, int optname,
|
||||
char __user *optval, int optlen)
|
||||
{
|
||||
mm_segment_t oldfs = get_fs();
|
||||
char *kernel_optval = NULL;
|
||||
int err, fput_needed;
|
||||
struct socket *sock;
|
||||
|
||||
|
@ -2063,6 +2065,22 @@ static int __sys_setsockopt(int fd, int level, int optname,
|
|||
if (err)
|
||||
goto out_put;
|
||||
|
||||
err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level,
|
||||
&optname, optval, &optlen,
|
||||
&kernel_optval);
|
||||
|
||||
if (err < 0) {
|
||||
goto out_put;
|
||||
} else if (err > 0) {
|
||||
err = 0;
|
||||
goto out_put;
|
||||
}
|
||||
|
||||
if (kernel_optval) {
|
||||
set_fs(KERNEL_DS);
|
||||
optval = (char __user __force *)kernel_optval;
|
||||
}
|
||||
|
||||
if (level == SOL_SOCKET)
|
||||
err =
|
||||
sock_setsockopt(sock, level, optname, optval,
|
||||
|
@ -2071,6 +2089,11 @@ static int __sys_setsockopt(int fd, int level, int optname,
|
|||
err =
|
||||
sock->ops->setsockopt(sock, level, optname, optval,
|
||||
optlen);
|
||||
|
||||
if (kernel_optval) {
|
||||
set_fs(oldfs);
|
||||
kfree(kernel_optval);
|
||||
}
|
||||
out_put:
|
||||
fput_light(sock->file, fput_needed);
|
||||
}
|
||||
|
@ -2093,6 +2116,7 @@ static int __sys_getsockopt(int fd, int level, int optname,
|
|||
{
|
||||
int err, fput_needed;
|
||||
struct socket *sock;
|
||||
int max_optlen;
|
||||
|
||||
sock = sockfd_lookup_light(fd, &err, &fput_needed);
|
||||
if (sock != NULL) {
|
||||
|
@ -2100,6 +2124,8 @@ static int __sys_getsockopt(int fd, int level, int optname,
|
|||
if (err)
|
||||
goto out_put;
|
||||
|
||||
max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
|
||||
|
||||
if (level == SOL_SOCKET)
|
||||
err =
|
||||
sock_getsockopt(sock, level, optname, optval,
|
||||
|
@ -2108,6 +2134,10 @@ static int __sys_getsockopt(int fd, int level, int optname,
|
|||
err =
|
||||
sock->ops->getsockopt(sock, level, optname, optval,
|
||||
optlen);
|
||||
|
||||
err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
|
||||
optval, optlen,
|
||||
max_optlen, err);
|
||||
out_put:
|
||||
fput_light(sock->file, fput_needed);
|
||||
}
|
||||
|
|
Loading…
Reference in New Issue