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| author | Eric Dumazet <edumazet@google.com> | 2019-10-10 20:17:44 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-10-13 10:13:08 -0700 |
| commit | ebb3b78db7bf842270a46fd4fe7cc45c78fa5ed6 (patch) | |
| tree | 9a0ecbc667473f785c77851f2db6c31f1fa3d2a4 /net/core/sock.c | |
| parent | d9b55bf7b6788ec0bd1db1acefbc4feb1399144a (diff) | |
| download | linux-stable-ebb3b78db7bf842270a46fd4fe7cc45c78fa5ed6.tar.gz linux-stable-ebb3b78db7bf842270a46fd4fe7cc45c78fa5ed6.tar.bz2 linux-stable-ebb3b78db7bf842270a46fd4fe7cc45c78fa5ed6.zip | |
tcp: annotate sk->sk_rcvbuf lockless reads
For the sake of tcp_poll(), there are few places where we fetch
sk->sk_rcvbuf while this field can change from IRQ or other cpu.
We need to add READ_ONCE() annotations, and also make sure write
sides use corresponding WRITE_ONCE() to avoid store-tearing.
Note that other transports probably need similar fixes.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/sock.c')
| -rw-r--r-- | net/core/sock.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index 2a053999df11..8c8f61e70141 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -831,7 +831,8 @@ set_rcvbuf: * returning the value we actually used in getsockopt * is the most desirable behavior. */ - sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); + WRITE_ONCE(sk->sk_rcvbuf, + max_t(int, val * 2, SOCK_MIN_RCVBUF)); break; case SO_RCVBUFFORCE: @@ -3204,7 +3205,7 @@ void sk_get_meminfo(const struct sock *sk, u32 *mem) memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); - mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; + mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf); mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; |