diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2024-10-18 04:41:00 +0300 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2024-10-23 14:17:35 +0300 |
| commit | c972c1c41d9b20fb38b54e77dcee763e27e715a9 (patch) | |
| tree | 32cf93781e6608687bbeea13262263e51841b085 | |
| parent | 7213a1c417d2c690de2c5aaa05b9dbec0d68a1b1 (diff) | |
| download | linux-c972c1c41d9b20fb38b54e77dcee763e27e715a9.tar.xz | |
ipv4: Switch inet_addr_hash() to less predictable hash.
Recently, commit 4a0ec2aa0704 ("ipv6: switch inet6_addr_hash()
to less predictable hash") and commit 4daf4dc275f1 ("ipv6: switch
inet6_acaddr_hash() to less predictable hash") hardened IPv6
address hash functions.
inet_addr_hash() is also highly predictable, and a malicious use
could abuse a specific bucket.
Let's follow the change on IPv4 by using jhash_1word().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241018014100.93776-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | include/net/ip.h | 5 | ||||
| -rw-r--r-- | net/ipv4/devinet.c | 2 |
2 files changed, 6 insertions, 1 deletions
diff --git a/include/net/ip.h b/include/net/ip.h index 4be0a6a603b2..0e548c1f2a0e 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -690,6 +690,11 @@ static inline unsigned int ipv4_addr_hash(__be32 ip) return (__force unsigned int) ip; } +static inline u32 __ipv4_addr_hash(const __be32 ip, const u32 initval) +{ + return jhash_1word((__force u32)ip, initval); +} + static inline u32 ipv4_portaddr_hash(const struct net *net, __be32 saddr, unsigned int port) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 0ff9c0abfaa0..5f859d01cbbe 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -121,7 +121,7 @@ struct inet_fill_args { static u32 inet_addr_hash(const struct net *net, __be32 addr) { - u32 val = (__force u32) addr ^ net_hash_mix(net); + u32 val = __ipv4_addr_hash(addr, net_hash_mix(net)); return hash_32(val, IN4_ADDR_HSIZE_SHIFT); } |