net/socket: Break down __sys_getsockopt

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>
This commit is contained in:
Breno Leitao 2023-10-16 06:47:42 -07:00 committed by Jens Axboe
parent 1406245c29
commit 0b05b0cd78
4 changed files with 44 additions and 34 deletions

View File

@ -378,7 +378,7 @@ 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; \
})

View File

@ -1869,11 +1869,11 @@ 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,

View File

@ -2010,14 +2010,6 @@ lenout:
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.
*

View File

@ -2333,6 +2333,43 @@ 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.
@ -2340,37 +2377,18 @@ 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;
}