diff options
| author | Anastasia Kovaleva <a.kovaleva@yadro.com> | 2024-10-03 13:44:31 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-10-17 16:24:35 +0300 |
| commit | 3be342e0332a7c83eb26fbb22bf156fdca467a5d (patch) | |
| tree | 303ea8d6fbc43a6b32a5498f26038ba67fb8cd0b | |
| parent | 563e6892e21d6ecabdf62103fc4e7b326d212334 (diff) | |
| download | linux-3be342e0332a7c83eb26fbb22bf156fdca467a5d.tar.xz | |
net: Fix an unsafe loop on the list
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>
| -rw-r--r-- | include/net/sock.h | 2 | ||||
| -rw-r--r-- | net/netlink/af_netlink.c | 3 |
2 files changed, 4 insertions, 1 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 2a1aee503848..c3961050b8e3 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -902,6 +902,8 @@ static inline void sk_add_bind2_node(struct sock *sk, struct hlist_head *list) hlist_for_each_entry(__sk, list, sk_bind_node) #define sk_for_each_bound_bhash2(__sk, list) \ hlist_for_each_entry(__sk, list, sk_bind2_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 8e7d5f17c58b..50e13207a05a 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2143,8 +2143,9 @@ 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); } |