[PATCH net-next 2/2] pppox: convert pppox_sk() to use container_of()

[Qingfang Deng <qingfang.deng@linux.dev>]

Use container_of() macro instead of direct pointer casting to get the
pppox_sock from a sock pointer. This improves type safety and removes
the requirement that sk must be the first struct member.

Signed-off-by: Qingfang Deng <qingfang.deng@linux.dev>
---
 include/linux/if_pppox.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/include/linux/if_pppox.h b/include/linux/if_pppox.h
index 636772693f9a..4f8d9e02cd7f 100644
--- a/include/linux/if_pppox.h
+++ b/include/linux/if_pppox.h
@@ -38,7 +38,6 @@ struct pptp_opt {
 #include <net/sock.h>
 
 struct pppox_sock {
-	/* struct sock must be the first member of pppox_sock */
 	struct sock sk;
 	struct ppp_channel chan;
 	struct pppox_sock __rcu	*next;	  /* for hash table */
@@ -54,7 +53,7 @@ struct pppox_sock {
 
 static inline struct pppox_sock *pppox_sk(struct sock *sk)
 {
-	return (struct pppox_sock *)sk;
+	return container_of(sk, struct pppox_sock, sk);
 }
 
 struct module;
-- 
2.43.0