This is a note to let you know that I've just added the patch titled
net: Change sock_getsockopt() to take the sk ptr instead of the sock ptr
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-change-sock_getsockopt-to-take-the-sk-ptr-instea.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9b1c36493c827100b8aa5b3dd82cdd808f29d801
Author: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
Date: Thu Sep 1 17:27:56 2022 -0700
net: Change sock_getsockopt() to take the sk ptr instead of the sock ptr
[ Upstream commit ba74a7608dc12fbbd8ea36e660087f08a81ef26a ]
A latter patch refactors bpf_getsockopt(SOL_SOCKET) with the
sock_getsockopt() to avoid code duplication and code
drift between the two duplicates.
The current sock_getsockopt() takes sock ptr as the argument.
The very first thing of this function is to get back the sk ptr
by 'sk = sock->sk'.
bpf_getsockopt() could be called when the sk does not have
the sock ptr created. Meaning sk->sk_socket is NULL. For example,
when a passive tcp connection has just been established but has yet
been accept()-ed. Thus, it cannot use the sock_getsockopt(sk->sk_socket)
or else it will pass a NULL ptr.
This patch moves all sock_getsockopt implementation to the newly
added sk_getsockopt(). The new sk_getsockopt() takes a sk ptr
and immediately gets the sock ptr by 'sock = sk->sk_socket'
The existing sock_getsockopt(sock) is changed to call
sk_getsockopt(sock->sk). All existing callers have both sock->sk
and sk->sk_socket pointer.
The latter patch will make bpf_getsockopt(SOL_SOCKET) call
sk_getsockopt(sk) directly. The bpf_getsockopt(SOL_SOCKET) does
not use the optnames that require sk->sk_socket, so it will
be safe.
Signed-off-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220902002756.2887884-1-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>
diff --git a/net/core/sock.c b/net/core/sock.c
index 769e969cd1dc5..95559d088a169 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1293,10 +1293,10 @@ static int groups_to_user(gid_t __user *dst, const struct group_info *src)
return 0;
}
-int sock_getsockopt(struct socket *sock, int level, int optname,
- char __user *optval, int __user *optlen)
+static int sk_getsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, int __user *optlen)
{
- struct sock *sk = sock->sk;
+ struct socket *sock = sk->sk_socket;
union {
int val;
@@ -1633,6 +1633,12 @@ int sock_getsockopt(struct socket *sock, 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, optval, optlen);
+}
+
/*
* Initialize an sk_lock.
*
