6.6-stable review patch. If anyone has any objections, please let me know.
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From: Breno Leitao leitao@debian.org
[ Upstream commit 0b05b0cd78c92371fdde6333d006f39eaf9e0860 ]
Split __sys_getsockopt() into two functions by removing the core logic into a sub-function (do_sock_getsockopt()). This will avoid code duplication when doing the same operation in other callers, for instance.
do_sock_getsockopt() will be called by io_uring getsockopt() command operation in the following patch.
The same was done for the setsockopt pair.
Suggested-by: Martin KaFai Lau martin.lau@linux.dev Signed-off-by: Breno Leitao leitao@debian.org Acked-by: Jakub Kicinski kuba@kernel.org Acked-by: Martin KaFai Lau martin.lau@kernel.org Link: https://lore.kernel.org/r/20231016134750.1381153-5-leitao@debian.org Signed-off-by: Jens Axboe axboe@kernel.dk Stable-dep-of: 33f339a1ba54 ("bpf, net: Fix a potential race in do_sock_getsockopt()") Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/bpf-cgroup.h | 2 +- include/net/sock.h | 4 +-- net/core/sock.c | 8 ----- net/socket.c | 64 ++++++++++++++++++++++++-------------- 4 files changed, 44 insertions(+), 34 deletions(-)
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index ebfd3c5a776a..2aa82b7aed89 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -379,7 +379,7 @@ static inline bool cgroup_bpf_sock_enabled(struct sock *sk, ({ \ int __ret = 0; \ if (cgroup_bpf_enabled(CGROUP_GETSOCKOPT)) \ - get_user(__ret, optlen); \ + copy_from_sockptr(&__ret, optlen, sizeof(int)); \ __ret; \ })
diff --git a/include/net/sock.h b/include/net/sock.h index bb010cc53b91..2a1aee503848 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1877,11 +1877,11 @@ int sock_setsockopt(struct socket *sock, int level, int op, sockptr_t optval, unsigned int optlen); int do_sock_setsockopt(struct socket *sock, bool compat, int level, int optname, sockptr_t optval, int optlen); +int do_sock_getsockopt(struct socket *sock, bool compat, int level, + int optname, sockptr_t optval, sockptr_t optlen);
int sk_getsockopt(struct sock *sk, int level, int optname, sockptr_t optval, sockptr_t optlen); -int sock_getsockopt(struct socket *sock, int level, int op, - char __user *optval, int __user *optlen); int sock_gettstamp(struct socket *sock, void __user *userstamp, bool timeval, bool time32); struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, diff --git a/net/core/sock.c b/net/core/sock.c index 55d85d50b3e4..bc2a4e38dcea 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2019,14 +2019,6 @@ int sk_getsockopt(struct sock *sk, int level, int optname, return 0; }
-int sock_getsockopt(struct socket *sock, int level, int optname, - char __user *optval, int __user *optlen) -{ - return sk_getsockopt(sock->sk, level, optname, - USER_SOCKPTR(optval), - USER_SOCKPTR(optlen)); -} - /* * Initialize an sk_lock. * diff --git a/net/socket.c b/net/socket.c index aa563fc0cee4..d275f5f14882 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2352,6 +2352,43 @@ SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname, INDIRECT_CALLABLE_DECLARE(bool tcp_bpf_bypass_getsockopt(int level, int optname));
+int do_sock_getsockopt(struct socket *sock, bool compat, int level, + int optname, sockptr_t optval, sockptr_t optlen) +{ + int max_optlen __maybe_unused; + const struct proto_ops *ops; + int err; + + err = security_socket_getsockopt(sock, level, optname); + if (err) + return err; + + if (!compat) + max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen); + + ops = READ_ONCE(sock->ops); + if (level == SOL_SOCKET) { + err = sk_getsockopt(sock->sk, level, optname, optval, optlen); + } else if (unlikely(!ops->getsockopt)) { + err = -EOPNOTSUPP; + } else { + if (WARN_ONCE(optval.is_kernel || optlen.is_kernel, + "Invalid argument type")) + return -EOPNOTSUPP; + + err = ops->getsockopt(sock, level, optname, optval.user, + optlen.user); + } + + if (!compat) + err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname, + optval, optlen, max_optlen, + err); + + return err; +} +EXPORT_SYMBOL(do_sock_getsockopt); + /* * Get a socket option. Because we don't know the option lengths we have * to pass a user mode parameter for the protocols to sort out. @@ -2359,37 +2396,18 @@ INDIRECT_CALLABLE_DECLARE(bool tcp_bpf_bypass_getsockopt(int level, int __sys_getsockopt(int fd, int level, int optname, char __user *optval, int __user *optlen) { - int max_optlen __maybe_unused; - const struct proto_ops *ops; int err, fput_needed; struct socket *sock; + bool compat;
sock = sockfd_lookup_light(fd, &err, &fput_needed); if (!sock) return err;
- err = security_socket_getsockopt(sock, level, optname); - if (err) - goto out_put; + compat = in_compat_syscall(); + err = do_sock_getsockopt(sock, compat, level, optname, + USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
- if (!in_compat_syscall()) - max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen); - - ops = READ_ONCE(sock->ops); - if (level == SOL_SOCKET) - err = sock_getsockopt(sock, level, optname, optval, optlen); - else if (unlikely(!ops->getsockopt)) - err = -EOPNOTSUPP; - else - err = ops->getsockopt(sock, level, optname, optval, - optlen); - - if (!in_compat_syscall()) - err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname, - USER_SOCKPTR(optval), - USER_SOCKPTR(optlen), - max_optlen, err); -out_put: fput_light(sock->file, fput_needed); return err; }