net: convert sock.sk_wmem_alloc from atomic_t to refcount_t

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Reshetova, Elena 2017-06-30 13:08:00 +03:00 committed by David S. Miller
parent 2638595afc
commit 14afee4b60
37 changed files with 74 additions and 85 deletions

View file

@ -164,7 +164,7 @@ static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
sizeof(struct sk_buff) +
sizeof(struct sctp_chunk);
atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
refcount_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
sk->sk_wmem_queued += chunk->skb->truesize;
sk_mem_charge(sk, chunk->skb->truesize);
}
@ -7684,7 +7684,7 @@ static void sctp_wfree(struct sk_buff *skb)
sizeof(struct sk_buff) +
sizeof(struct sctp_chunk);
atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
WARN_ON(refcount_sub_and_test(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc));
/*
* This undoes what is done via sctp_set_owner_w and sk_mem_charge