Add a helper that copies either a native or compat bpf_fprog from userspace after verifying the length, and remove the compat setsockopt handlers that now aren't required. Signed-off-by: Christoph Hellwig --- include/linux/filter.h | 4 ++-- include/net/compat.h | 1 - net/compat.c | 45 +----------------------------------------- net/core/filter.c | 23 +++++++++++++++++++++ net/core/sock.c | 30 ++++++++++------------------ net/packet/af_packet.c | 33 ++++--------------------------- 6 files changed, 40 insertions(+), 96 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index 0b0144752d780a..4d049c8e1fbeaa 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -502,13 +502,11 @@ static inline bool insn_is_zext(const struct bpf_insn *insn) offsetof(TYPE, MEMBER); \ }) -#ifdef CONFIG_COMPAT /* A struct sock_filter is architecture independent. */ struct compat_sock_fprog { u16 len; compat_uptr_t filter; /* struct sock_filter * */ }; -#endif struct sock_fprog_kern { u16 len; @@ -1278,4 +1276,6 @@ struct bpf_sockopt_kern { s32 retval; }; +int copy_bpf_fprog_from_user(struct sock_fprog *dst, void __user *src, int len); + #endif /* __LINUX_FILTER_H__ */ diff --git a/include/net/compat.h b/include/net/compat.h index f241666117d88c..745db0d605b62b 100644 --- a/include/net/compat.h +++ b/include/net/compat.h @@ -61,7 +61,6 @@ int __get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg, compat_size_t *len); int get_compat_msghdr(struct msghdr *, struct compat_msghdr __user *, struct sockaddr __user **, struct iovec **); -struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval); int put_cmsg_compat(struct msghdr*, int, int, int, void *); int cmsghdr_from_user_compat_to_kern(struct msghdr *, struct sock *, diff --git a/net/compat.c b/net/compat.c index 5e3041a2c37d4d..3e6c2c5ff2609c 100644 --- a/net/compat.c +++ b/net/compat.c @@ -335,49 +335,6 @@ void scm_detach_fds_compat(struct msghdr *kmsg, struct scm_cookie *scm) __scm_destroy(scm); } -/* allocate a 64-bit sock_fprog on the user stack for duration of syscall. */ -struct sock_fprog __user *get_compat_bpf_fprog(char __user *optval) -{ - struct compat_sock_fprog __user *fprog32 = (struct compat_sock_fprog __user *)optval; - struct sock_fprog __user *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog)); - struct compat_sock_fprog f32; - struct sock_fprog f; - - if (copy_from_user(&f32, fprog32, sizeof(*fprog32))) - return NULL; - memset(&f, 0, sizeof(f)); - f.len = f32.len; - f.filter = compat_ptr(f32.filter); - if (copy_to_user(kfprog, &f, sizeof(struct sock_fprog))) - return NULL; - - return kfprog; -} -EXPORT_SYMBOL_GPL(get_compat_bpf_fprog); - -static int do_set_attach_filter(struct socket *sock, int level, int optname, - char __user *optval, unsigned int optlen) -{ - struct sock_fprog __user *kfprog; - - kfprog = get_compat_bpf_fprog(optval); - if (!kfprog) - return -EFAULT; - - return sock_setsockopt(sock, level, optname, (char __user *)kfprog, - sizeof(struct sock_fprog)); -} - -static int compat_sock_setsockopt(struct socket *sock, int level, int optname, - char __user *optval, unsigned int optlen) -{ - if (optname == SO_ATTACH_FILTER || - optname == SO_ATTACH_REUSEPORT_CBPF) - return do_set_attach_filter(sock, level, optname, - optval, optlen); - return sock_setsockopt(sock, level, optname, optval, optlen); -} - static int __compat_sys_setsockopt(int fd, int level, int optname, char __user *optval, unsigned int optlen) { @@ -396,7 +353,7 @@ static int __compat_sys_setsockopt(int fd, int level, int optname, } if (level == SOL_SOCKET) - err = compat_sock_setsockopt(sock, level, + err = sock_setsockopt(sock, level, optname, optval, optlen); else if (sock->ops->compat_setsockopt) err = sock->ops->compat_setsockopt(sock, level, diff --git a/net/core/filter.c b/net/core/filter.c index bdd2382e655d85..2bf6624796d86f 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -77,6 +77,29 @@ #include #include +int copy_bpf_fprog_from_user(struct sock_fprog *dst, void __user *src, int len) +{ + if (in_compat_syscall()) { + struct compat_sock_fprog f32; + + if (len != sizeof(f32)) + return -EINVAL; + if (copy_from_user(&f32, src, sizeof(f32))) + return -EFAULT; + memset(dst, 0, sizeof(*dst)); + dst->len = f32.len; + dst->filter = compat_ptr(f32.filter); + } else { + if (len != sizeof(*dst)) + return -EINVAL; + if (copy_from_user(dst, src, sizeof(*dst))) + return -EFAULT; + } + + return 0; +} +EXPORT_SYMBOL_GPL(copy_bpf_fprog_from_user); + /** * sk_filter_trim_cap - run a packet through a socket filter * @sk: sock associated with &sk_buff diff --git a/net/core/sock.c b/net/core/sock.c index 11d6f77dd56207..e085df79482520 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1059,19 +1059,14 @@ int sock_setsockopt(struct socket *sock, int level, int optname, ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen, optname == SO_SNDTIMEO_OLD); break; - case SO_ATTACH_FILTER: - ret = -EINVAL; - if (optlen == sizeof(struct sock_fprog)) { - struct sock_fprog fprog; - - ret = -EFAULT; - if (copy_from_user(&fprog, optval, sizeof(fprog))) - break; + case SO_ATTACH_FILTER: { + struct sock_fprog fprog; + ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); + if (!ret) ret = sk_attach_filter(&fprog, sk); - } break; - + } case SO_ATTACH_BPF: ret = -EINVAL; if (optlen == sizeof(u32)) { @@ -1085,19 +1080,14 @@ int sock_setsockopt(struct socket *sock, int level, int optname, } break; - case SO_ATTACH_REUSEPORT_CBPF: - ret = -EINVAL; - if (optlen == sizeof(struct sock_fprog)) { - struct sock_fprog fprog; - - ret = -EFAULT; - if (copy_from_user(&fprog, optval, sizeof(fprog))) - break; + case SO_ATTACH_REUSEPORT_CBPF: { + struct sock_fprog fprog; + ret = copy_bpf_fprog_from_user(&fprog, optval, optlen); + if (!ret) ret = sk_reuseport_attach_filter(&fprog, sk); - } break; - + } case SO_ATTACH_REUSEPORT_EBPF: ret = -EINVAL; if (optlen == sizeof(u32)) { diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 781fee93b7d5e3..35aee9e980536d 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1545,10 +1545,10 @@ static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data, if (sock_flag(&po->sk, SOCK_FILTER_LOCKED)) return -EPERM; - if (len != sizeof(fprog)) - return -EINVAL; - if (copy_from_user(&fprog, data, len)) - return -EFAULT; + + ret = copy_bpf_fprog_from_user(&fprog, data, len); + if (ret) + return ret; ret = bpf_prog_create_from_user(&new, &fprog, NULL, false); if (ret) @@ -4040,28 +4040,6 @@ static int packet_getsockopt(struct socket *sock, int level, int optname, return 0; } - -#ifdef CONFIG_COMPAT -static int compat_packet_setsockopt(struct socket *sock, int level, int optname, - char __user *optval, unsigned int optlen) -{ - struct packet_sock *po = pkt_sk(sock->sk); - - if (level != SOL_PACKET) - return -ENOPROTOOPT; - - if (optname == PACKET_FANOUT_DATA && - po->fanout && po->fanout->type == PACKET_FANOUT_CBPF) { - optval = (char __user *)get_compat_bpf_fprog(optval); - if (!optval) - return -EFAULT; - optlen = sizeof(struct sock_fprog); - } - - return packet_setsockopt(sock, level, optname, optval, optlen); -} -#endif - static int packet_notifier(struct notifier_block *this, unsigned long msg, void *ptr) { @@ -4549,9 +4527,6 @@ static const struct proto_ops packet_ops = { .shutdown = sock_no_shutdown, .setsockopt = packet_setsockopt, .getsockopt = packet_getsockopt, -#ifdef CONFIG_COMPAT - .compat_setsockopt = compat_packet_setsockopt, -#endif .sendmsg = packet_sendmsg, .recvmsg = packet_recvmsg, .mmap = packet_mmap, -- 2.27.0