From: Martin KaFai Lau <martin.lau@xxxxxxxxxx> [ Upstream commit 4ff09db1b79b98b4a2a7511571c640b76cab3beb ] This patch changes sk_getsockopt() to take the sockptr_t argument such that it can be used by bpf_getsockopt(SOL_SOCKET) in a latter patch. security_socket_getpeersec_stream() is not changed. It stays with the __user ptr (optval.user and optlen.user) to avoid changes to other security hooks. bpf_getsockopt(SOL_SOCKET) also does not support SO_PEERSEC. Signed-off-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220902002802.2888419-1-kafai@xxxxxx Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Stable-dep-of: 5a287d3d2b9d ("lsm: fix default return value of the socket_getpeersec_*() hooks") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- include/linux/filter.h | 3 +-- include/linux/sockptr.h | 5 +++++ net/core/filter.c | 5 ++--- net/core/sock.c | 43 +++++++++++++++++++++++------------------ 4 files changed, 32 insertions(+), 24 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index bc6ce4b202a80..cd56e53bd42e2 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -892,8 +892,7 @@ int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); void sk_reuseport_prog_free(struct bpf_prog *prog); int sk_detach_filter(struct sock *sk); -int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, - unsigned int len); +int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len); bool sk_filter_charge(struct sock *sk, struct sk_filter *fp); void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); diff --git a/include/linux/sockptr.h b/include/linux/sockptr.h index ea193414298b7..38862819e77a1 100644 --- a/include/linux/sockptr.h +++ b/include/linux/sockptr.h @@ -64,6 +64,11 @@ static inline int copy_to_sockptr_offset(sockptr_t dst, size_t offset, return 0; } +static inline int copy_to_sockptr(sockptr_t dst, const void *src, size_t size) +{ + return copy_to_sockptr_offset(dst, 0, src, size); +} + static inline void *memdup_sockptr(sockptr_t src, size_t len) { void *p = kmalloc_track_caller(len, GFP_USER | __GFP_NOWARN); diff --git a/net/core/filter.c b/net/core/filter.c index 6cfc8fb0562a2..49e4d1535cc82 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -9903,8 +9903,7 @@ int sk_detach_filter(struct sock *sk) } EXPORT_SYMBOL_GPL(sk_detach_filter); -int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, - unsigned int len) +int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len) { struct sock_fprog_kern *fprog; struct sk_filter *filter; @@ -9935,7 +9934,7 @@ int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, goto out; ret = -EFAULT; - if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog))) + if (copy_to_sockptr(optval, fprog->filter, bpf_classic_proglen(fprog))) goto out; /* Instead of bytes, the API requests to return the number diff --git a/net/core/sock.c b/net/core/sock.c index 95559d088a169..42da46965b16f 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -644,8 +644,8 @@ static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen) return ret; } -static int sock_getbindtodevice(struct sock *sk, char __user *optval, - int __user *optlen, int len) +static int sock_getbindtodevice(struct sock *sk, sockptr_t optval, + sockptr_t optlen, int len) { int ret = -ENOPROTOOPT; #ifdef CONFIG_NETDEVICES @@ -668,12 +668,12 @@ static int sock_getbindtodevice(struct sock *sk, char __user *optval, len = strlen(devname) + 1; ret = -EFAULT; - if (copy_to_user(optval, devname, len)) + if (copy_to_sockptr(optval, devname, len)) goto out; zero: ret = -EFAULT; - if (put_user(len, optlen)) + if (copy_to_sockptr(optlen, &len, sizeof(int))) goto out; ret = 0; @@ -1281,20 +1281,23 @@ static void cred_to_ucred(struct pid *pid, const struct cred *cred, } } -static int groups_to_user(gid_t __user *dst, const struct group_info *src) +static int groups_to_user(sockptr_t dst, const struct group_info *src) { struct user_namespace *user_ns = current_user_ns(); int i; - for (i = 0; i < src->ngroups; i++) - if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i)) + for (i = 0; i < src->ngroups; i++) { + gid_t gid = from_kgid_munged(user_ns, src->gid[i]); + + if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid))) return -EFAULT; + } return 0; } static int sk_getsockopt(struct sock *sk, int level, int optname, - char __user *optval, int __user *optlen) + sockptr_t optval, sockptr_t optlen) { struct socket *sock = sk->sk_socket; @@ -1312,7 +1315,7 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, int lv = sizeof(int); int len; - if (get_user(len, optlen)) + if (copy_from_sockptr(&len, optlen, sizeof(int))) return -EFAULT; if (len < 0) return -EINVAL; @@ -1445,7 +1448,7 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); spin_unlock(&sk->sk_peer_lock); - if (copy_to_user(optval, &peercred, len)) + if (copy_to_sockptr(optval, &peercred, len)) return -EFAULT; goto lenout; } @@ -1463,11 +1466,11 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, if (len < n * sizeof(gid_t)) { len = n * sizeof(gid_t); put_cred(cred); - return put_user(len, optlen) ? -EFAULT : -ERANGE; + return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE; } len = n * sizeof(gid_t); - ret = groups_to_user((gid_t __user *)optval, cred->group_info); + ret = groups_to_user(optval, cred->group_info); put_cred(cred); if (ret) return ret; @@ -1483,7 +1486,7 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, return -ENOTCONN; if (lv < len) return -EINVAL; - if (copy_to_user(optval, address, len)) + if (copy_to_sockptr(optval, address, len)) return -EFAULT; goto lenout; } @@ -1500,7 +1503,7 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, break; case SO_PEERSEC: - return security_socket_getpeersec_stream(sock, optval, optlen, len); + return security_socket_getpeersec_stream(sock, optval.user, optlen.user, len); case SO_MARK: v.val = sk->sk_mark; @@ -1528,7 +1531,7 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, return sock_getbindtodevice(sk, optval, optlen, len); case SO_GET_FILTER: - len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); + len = sk_get_filter(sk, optval, len); if (len < 0) return len; @@ -1575,7 +1578,7 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, sk_get_meminfo(sk, meminfo); len = min_t(unsigned int, len, sizeof(meminfo)); - if (copy_to_user(optval, &meminfo, len)) + if (copy_to_sockptr(optval, &meminfo, len)) return -EFAULT; goto lenout; @@ -1625,10 +1628,10 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, if (len > lv) len = lv; - if (copy_to_user(optval, &v, len)) + if (copy_to_sockptr(optval, &v, len)) return -EFAULT; lenout: - if (put_user(len, optlen)) + if (copy_to_sockptr(optlen, &len, sizeof(int))) return -EFAULT; return 0; } @@ -1636,7 +1639,9 @@ static int sk_getsockopt(struct sock *sk, int level, int optname, int sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { - return sk_getsockopt(sock->sk, level, optname, optval, optlen); + return sk_getsockopt(sock->sk, level, optname, + USER_SOCKPTR(optval), + USER_SOCKPTR(optlen)); } /* -- 2.43.0
