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author | Riccardo Paolo Bestetti <pbl@bestov.io> | 2022-06-17 10:54:35 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-06-17 11:41:34 +0100 |
commit | b4a028c4d031c27704ad73b1195ca69a1206941e (patch) | |
tree | 52dcd1febe816f60868811d29e412509f8a60a8c /net | |
parent | 2b04495e21cdb9b45c28c6aeb2da560184de20a3 (diff) | |
download | lwn-b4a028c4d031c27704ad73b1195ca69a1206941e.tar.gz lwn-b4a028c4d031c27704ad73b1195ca69a1206941e.zip |
ipv4: ping: fix bind address validity check
Commit 8ff978b8b222 ("ipv4/raw: support binding to nonlocal addresses")
introduced a helper function to fold duplicated validity checks of bind
addresses into inet_addr_valid_or_nonlocal(). However, this caused an
unintended regression in ping_check_bind_addr(), which previously would
reject binding to multicast and broadcast addresses, but now these are
both incorrectly allowed as reported in [1].
This patch restores the original check. A simple reordering is done to
improve readability and make it evident that multicast and broadcast
addresses should not be allowed. Also, add an early exit for INADDR_ANY
which replaces lost behavior added by commit 0ce779a9f501 ("net: Avoid
unnecessary inet_addr_type() call when addr is INADDR_ANY").
Furthermore, this patch introduces regression selftests to catch these
specific cases.
[1] https://lore.kernel.org/netdev/CANP3RGdkAcDyAZoT1h8Gtuu0saq+eOrrTiWbxnOs+5zn+cpyKg@mail.gmail.com/
Fixes: 8ff978b8b222 ("ipv4/raw: support binding to nonlocal addresses")
Cc: Miaohe Lin <linmiaohe@huawei.com>
Reported-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: Riccardo Paolo Bestetti <pbl@bestov.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/ipv4/ping.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 1a43ca73f94d..3c6101def7d6 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -319,12 +319,16 @@ static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk, pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n", sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port)); + if (addr->sin_addr.s_addr == htonl(INADDR_ANY)) + return 0; + tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id; chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id); - if (!inet_addr_valid_or_nonlocal(net, inet_sk(sk), - addr->sin_addr.s_addr, - chk_addr_ret)) + if (chk_addr_ret == RTN_MULTICAST || + chk_addr_ret == RTN_BROADCAST || + (chk_addr_ret != RTN_LOCAL && + !inet_can_nonlocal_bind(net, isk))) return -EADDRNOTAVAIL; #if IS_ENABLED(CONFIG_IPV6) |