diff options
| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-08-03 09:37:31 -0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-08-03 09:37:31 -0300 |
| commit | b1aa3db2c13ec0c63a73bd8fc5dfbfb112e3ff56 (patch) | |
| tree | 92ce9158daae144032cc6297ab8fdbad12664247 /net/ipv4/tcp_ipv4.c | |
| parent | 7c43b0c1d499c790cdb5623d27fdcef544ddb566 (diff) | |
| parent | bcf876870b95592b52519ed4aafcf9d95999bc9c (diff) | |
Merge remote-tracking branch 'torvalds/master' into perf/core
Minor conflict in tools/perf/arch/arm/util/auxtrace.c as one fix there
was cherry-picked for the last perf/urgent pull req to Linus, so was
already there.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index ad6435ba6d72..04bfcbbfee83 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1111,9 +1111,21 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index); if (key) { - /* Pre-existing entry - just update that one. */ - memcpy(key->key, newkey, newkeylen); - key->keylen = newkeylen; + /* Pre-existing entry - just update that one. + * Note that the key might be used concurrently. + * data_race() is telling kcsan that we do not care of + * key mismatches, since changing MD5 key on live flows + * can lead to packet drops. + */ + data_race(memcpy(key->key, newkey, newkeylen)); + + /* Pairs with READ_ONCE() in tcp_md5_hash_key(). + * Also note that a reader could catch new key->keylen value + * but old key->key[], this is the reason we use __GFP_ZERO + * at sock_kmalloc() time below these lines. + */ + WRITE_ONCE(key->keylen, newkeylen); + return 0; } @@ -1129,7 +1141,7 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, rcu_assign_pointer(tp->md5sig_info, md5sig); } - key = sock_kmalloc(sk, sizeof(*key), gfp); + key = sock_kmalloc(sk, sizeof(*key), gfp | __GFP_ZERO); if (!key) return -ENOMEM; if (!tcp_alloc_md5sig_pool()) { |