mptcp: annotate data-races around msk->rmem_fwd_alloc

msk->rmem_fwd_alloc can be read locklessly.

Add mptcp_rmem_fwd_alloc_add(), similar to sk_forward_alloc_add(),
and appropriate READ_ONCE()/WRITE_ONCE() annotations.

Fixes: 6511882cdd ("mptcp: allocate fwd memory separately on the rx and tx path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2023-08-31 13:52:10 +00:00 коммит произвёл David S. Miller
Родитель 5e6300e7b3
Коммит 9531e4a83f
1 изменённых файлов: 13 добавлений и 6 удалений

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@ -134,9 +134,15 @@ static void mptcp_drop(struct sock *sk, struct sk_buff *skb)
__kfree_skb(skb);
}
static void mptcp_rmem_fwd_alloc_add(struct sock *sk, int size)
{
WRITE_ONCE(mptcp_sk(sk)->rmem_fwd_alloc,
mptcp_sk(sk)->rmem_fwd_alloc + size);
}
static void mptcp_rmem_charge(struct sock *sk, int size)
{
mptcp_sk(sk)->rmem_fwd_alloc -= size;
mptcp_rmem_fwd_alloc_add(sk, -size);
}
static bool mptcp_try_coalesce(struct sock *sk, struct sk_buff *to,
@ -177,7 +183,7 @@ static bool mptcp_ooo_try_coalesce(struct mptcp_sock *msk, struct sk_buff *to,
static void __mptcp_rmem_reclaim(struct sock *sk, int amount)
{
amount >>= PAGE_SHIFT;
mptcp_sk(sk)->rmem_fwd_alloc -= amount << PAGE_SHIFT;
mptcp_rmem_charge(sk, amount << PAGE_SHIFT);
__sk_mem_reduce_allocated(sk, amount);
}
@ -186,7 +192,7 @@ static void mptcp_rmem_uncharge(struct sock *sk, int size)
struct mptcp_sock *msk = mptcp_sk(sk);
int reclaimable;
msk->rmem_fwd_alloc += size;
mptcp_rmem_fwd_alloc_add(sk, size);
reclaimable = msk->rmem_fwd_alloc - sk_unused_reserved_mem(sk);
/* see sk_mem_uncharge() for the rationale behind the following schema */
@ -341,7 +347,7 @@ static bool mptcp_rmem_schedule(struct sock *sk, struct sock *ssk, int size)
if (!__sk_mem_raise_allocated(sk, size, amt, SK_MEM_RECV))
return false;
msk->rmem_fwd_alloc += amount;
mptcp_rmem_fwd_alloc_add(sk, amount);
return true;
}
@ -3258,7 +3264,7 @@ void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags)
* inet_sock_destruct() will dispose it
*/
sk_forward_alloc_add(sk, msk->rmem_fwd_alloc);
msk->rmem_fwd_alloc = 0;
WRITE_ONCE(msk->rmem_fwd_alloc, 0);
mptcp_token_destroy(msk);
mptcp_pm_free_anno_list(msk);
mptcp_free_local_addr_list(msk);
@ -3522,7 +3528,8 @@ static void mptcp_shutdown(struct sock *sk, int how)
static int mptcp_forward_alloc_get(const struct sock *sk)
{
return READ_ONCE(sk->sk_forward_alloc) + mptcp_sk(sk)->rmem_fwd_alloc;
return READ_ONCE(sk->sk_forward_alloc) +
READ_ONCE(mptcp_sk(sk)->rmem_fwd_alloc);
}
static int mptcp_ioctl_outq(const struct mptcp_sock *msk, u64 v)