mirror of
https://github.com/torvalds/linux.git
synced 2024-11-10 22:21:40 +00:00
633547973f
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>
100 lines
2.7 KiB
C
100 lines
2.7 KiB
C
/* ar-skbuff.c: socket buffer destruction handling
|
|
*
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/net.h>
|
|
#include <linux/skbuff.h>
|
|
#include <net/sock.h>
|
|
#include <net/af_rxrpc.h>
|
|
#include "ar-internal.h"
|
|
|
|
#define select_skb_count(op) (op >= rxrpc_skb_tx_cleaned ? &rxrpc_n_tx_skbs : &rxrpc_n_rx_skbs)
|
|
|
|
/*
|
|
* Note the allocation or reception of a socket buffer.
|
|
*/
|
|
void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
int n = atomic_inc_return(select_skb_count(op));
|
|
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
|
|
}
|
|
|
|
/*
|
|
* Note the re-emergence of a socket buffer from a queue or buffer.
|
|
*/
|
|
void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
if (skb) {
|
|
int n = atomic_read(select_skb_count(op));
|
|
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Note the addition of a ref on a socket buffer.
|
|
*/
|
|
void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
int n = atomic_inc_return(select_skb_count(op));
|
|
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
|
|
skb_get(skb);
|
|
}
|
|
|
|
/*
|
|
* Note the destruction of a socket buffer.
|
|
*/
|
|
void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
if (skb) {
|
|
int n;
|
|
CHECK_SLAB_OKAY(&skb->users);
|
|
n = atomic_dec_return(select_skb_count(op));
|
|
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
|
|
kfree_skb(skb);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Note the injected loss of a socket buffer.
|
|
*/
|
|
void rxrpc_lose_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
if (skb) {
|
|
int n;
|
|
CHECK_SLAB_OKAY(&skb->users);
|
|
n = atomic_dec_return(select_skb_count(op));
|
|
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
|
|
kfree_skb(skb);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Clear a queue of socket buffers.
|
|
*/
|
|
void rxrpc_purge_queue(struct sk_buff_head *list)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
struct sk_buff *skb;
|
|
while ((skb = skb_dequeue((list))) != NULL) {
|
|
int n = atomic_dec_return(select_skb_count(rxrpc_skb_rx_purged));
|
|
trace_rxrpc_skb(skb, rxrpc_skb_rx_purged,
|
|
refcount_read(&skb->users), n, here);
|
|
kfree_skb(skb);
|
|
}
|
|
}
|