diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-10-06 11:53:46 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-10-12 17:50:37 -0700 |
| commit | 21985f43376cee092702d6cb963ff97a9d2ede68 (patch) | |
| tree | 0084a093718e00e822b53495b5f506a2aee4ea15 /net | |
| parent | 3c52c6bb831f6335c176a0fc7214e26f43adbd11 (diff) | |
udp: Call inet6_destroy_sock() in setsockopt(IPV6_ADDRFORM).
Commit 4b340ae20d0e ("IPv6: Complete IPV6_DONTFRAG support") forgot
to add a change to free inet6_sk(sk)->rxpmtu while converting an IPv6
socket into IPv4 with IPV6_ADDRFORM. After conversion, sk_prot is
changed to udp_prot and ->destroy() never cleans it up, resulting in
a memory leak.
This is due to the discrepancy between inet6_destroy_sock() and
IPV6_ADDRFORM, so let's call inet6_destroy_sock() from IPV6_ADDRFORM
to remove the difference.
However, this is not enough for now because rxpmtu can be changed
without lock_sock() after commit 03485f2adcde ("udpv6: Add lockless
sendmsg() support"). We will fix this case in the following patch.
Note we will rename inet6_destroy_sock() to inet6_cleanup_sock() and
remove unnecessary inet6_destroy_sock() calls in sk_prot->destroy()
in the future.
Fixes: 4b340ae20d0e ("IPv6: Complete IPV6_DONTFRAG support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/af_inet6.c | 6 | ||||
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 20 |
2 files changed, 14 insertions, 12 deletions
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index d40b7d60e00e..ded827944fa6 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -510,6 +510,12 @@ void inet6_destroy_sock(struct sock *sk) } EXPORT_SYMBOL_GPL(inet6_destroy_sock); +void inet6_cleanup_sock(struct sock *sk) +{ + inet6_destroy_sock(sk); +} +EXPORT_SYMBOL_GPL(inet6_cleanup_sock); + /* * This does both peername and sockname. */ diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 408345fc4c5c..a20edae868fd 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -431,9 +431,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, if (optlen < sizeof(int)) goto e_inval; if (val == PF_INET) { - struct ipv6_txoptions *opt; - struct sk_buff *pktopt; - if (sk->sk_type == SOCK_RAW) break; @@ -464,7 +461,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, break; } - fl6_free_socklist(sk); __ipv6_sock_mc_close(sk); __ipv6_sock_ac_close(sk); @@ -501,14 +497,14 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sk->sk_socket->ops = &inet_dgram_ops; sk->sk_family = PF_INET; } - opt = xchg((__force struct ipv6_txoptions **)&np->opt, - NULL); - if (opt) { - atomic_sub(opt->tot_len, &sk->sk_omem_alloc); - txopt_put(opt); - } - pktopt = xchg(&np->pktoptions, NULL); - kfree_skb(pktopt); + + /* Disable all options not to allocate memory anymore, + * but there is still a race. See the lockless path + * in udpv6_sendmsg() and ipv6_local_rxpmtu(). + */ + np->rxopt.all = 0; + + inet6_cleanup_sock(sk); /* * ... and add it to the refcnt debug socks count |