From: Anastasia Kovaleva <a.kovaleva@yadro.com> stable inclusion from stable-v5.10.227 commit 68ad5da6ca630a276f0a5c924179e57724d00013 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYRDW CVE: CVE-2024-50024 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 1dae9f1187189bc09ff6d25ca97ead711f7e26f9 upstream. The kernel may crash when deleting a genetlink family if there are still listeners for that family: Oops: Kernel access of bad area, sig: 11 [#1] ... NIP [c000000000c080bc] netlink_update_socket_mc+0x3c/0xc0 LR [c000000000c0f764] __netlink_clear_multicast_users+0x74/0xc0 Call Trace: __netlink_clear_multicast_users+0x74/0xc0 genl_unregister_family+0xd4/0x2d0 Change the unsafe loop on the list to a safe one, because inside the loop there is an element removal from this list. Fixes: b8273570f802 ("genetlink: fix netns vs. netlink table locking (2)") Cc: stable@vger.kernel.org Signed-off-by: Anastasia Kovaleva <a.kovaleva@yadro.com> Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20241003104431.12391-1-a.kovaleva@yadro.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Wang Liang <wangliang74@huawei.com> --- include/net/sock.h | 2 ++ net/netlink/af_netlink.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/net/sock.h b/include/net/sock.h index 2a78dd349577..13f62fd4dbc7 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -853,6 +853,8 @@ static inline void sk_add_bind_node(struct sock *sk, hlist_for_each_entry_safe(__sk, tmp, list, sk_node) #define sk_for_each_bound(__sk, list) \ hlist_for_each_entry(__sk, list, sk_bind_node) +#define sk_for_each_bound_safe(__sk, tmp, list) \ + hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node) /** * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index b9d1b3a68cba..1bb8a0268c1a 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2172,8 +2172,9 @@ void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) { struct sock *sk; struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; + struct hlist_node *tmp; - sk_for_each_bound(sk, &tbl->mc_list) + sk_for_each_bound_safe(sk, tmp, &tbl->mc_list) netlink_update_socket_mc(nlk_sk(sk), group, 0); } -- 2.34.1