diff options
| author | Eric Biggers <ebiggers@kernel.org> | 2025-10-22 15:12:09 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-10-23 18:49:55 -0700 |
| commit | 05774d7e4201b673b415d65a1344dc396e7c00e1 (patch) | |
| tree | 5cbb9e6e440a8e4a2604ad08840c86608de98e0c /net/ipv4 | |
| parent | 9ff86092655f7a22cc115188e3bf1b88ef49ec9e (diff) | |
tcp: Remove unnecessary null check in tcp_inbound_md5_hash()
The 'if (!key && hash_location)' check in tcp_inbound_md5_hash() implies
that hash_location might be null. However, later code in the function
dereferences hash_location anyway, without checking for null first.
Fortunately, there is no real bug, since tcp_inbound_md5_hash() is
called only with non-null values of hash_location.
Therefore, remove the unnecessary and misleading null check of
hash_location. This silences a Smatch static checker warning
(https://lore.kernel.org/netdev/aPi4b6aWBbBR52P1@stanley.mountain/)
Also fix the related comment at the beginning of the function.
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://patch.msgid.link/20251022221209.19716-1-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index e15b38f6bd2d..b79da6d39392 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4886,18 +4886,16 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, int family, int l3index, const __u8 *hash_location) { /* This gets called for each TCP segment that has TCP-MD5 option. - * We have 3 drop cases: - * o No MD5 hash and one expected. - * o MD5 hash and we're not expecting one. - * o MD5 hash and its wrong. + * We have 2 drop cases: + * o An MD5 signature is present, but we're not expecting one. + * o The MD5 signature is wrong. */ const struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_key *key; u8 newhash[16]; key = tcp_md5_do_lookup(sk, l3index, saddr, family); - - if (!key && hash_location) { + if (!key) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); trace_tcp_hash_md5_unexpected(sk, skb); return SKB_DROP_REASON_TCP_MD5UNEXPECTED; |