linux/net/atm/raw.c
Kuniyuki Iwashima 7851263998 atm: Revert atm_account_tx() if copy_from_iter_full() fails.
In vcc_sendmsg(), we account skb->truesize to sk->sk_wmem_alloc by
atm_account_tx().

It is expected to be reverted by atm_pop_raw() later called by
vcc->dev->ops->send(vcc, skb).

However, vcc_sendmsg() misses the same revert when copy_from_iter_full()
fails, and then we will leak a socket.

Let's factorise the revert part as atm_return_tx() and call it in
the failure path.

Note that the corresponding sk_wmem_alloc operation can be found in
alloc_tx() as of the blamed commit.

  $ git blame -L:alloc_tx net/atm/common.c c55fa3cccb~

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Simon Horman <horms@kernel.org>
Closes: https://lore.kernel.org/netdev/20250614161959.GR414686@horms.kernel.org/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250616182147.963333-3-kuni1840@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-17 18:42:44 -07:00

94 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* net/atm/raw.c - Raw AAL0 and AAL5 transports */
/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
#include <linux/module.h>
#include <linux/atmdev.h>
#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include "common.h"
#include "protocols.h"
/*
* SKB == NULL indicates that the link is being closed
*/
static void atm_push_raw(struct atm_vcc *vcc, struct sk_buff *skb)
{
if (skb) {
struct sock *sk = sk_atm(vcc);
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk);
}
}
static void atm_pop_raw(struct atm_vcc *vcc, struct sk_buff *skb)
{
struct sock *sk = sk_atm(vcc);
pr_debug("(%d) %d -= %d\n",
vcc->vci, sk_wmem_alloc_get(sk), ATM_SKB(skb)->acct_truesize);
atm_return_tx(vcc, skb);
dev_kfree_skb_any(skb);
sk->sk_write_space(sk);
}
static int atm_send_aal0(struct atm_vcc *vcc, struct sk_buff *skb)
{
/*
* Note that if vpi/vci are _ANY or _UNSPEC the below will
* still work
*/
if (!capable(CAP_NET_ADMIN) &&
(((u32 *)skb->data)[0] & (ATM_HDR_VPI_MASK | ATM_HDR_VCI_MASK)) !=
((vcc->vpi << ATM_HDR_VPI_SHIFT) |
(vcc->vci << ATM_HDR_VCI_SHIFT))) {
kfree_skb(skb);
return -EADDRNOTAVAIL;
}
if (vcc->dev->ops->send_bh)
return vcc->dev->ops->send_bh(vcc, skb);
return vcc->dev->ops->send(vcc, skb);
}
int atm_init_aal0(struct atm_vcc *vcc)
{
vcc->push = atm_push_raw;
vcc->pop = atm_pop_raw;
vcc->push_oam = NULL;
vcc->send = atm_send_aal0;
return 0;
}
int atm_init_aal34(struct atm_vcc *vcc)
{
vcc->push = atm_push_raw;
vcc->pop = atm_pop_raw;
vcc->push_oam = NULL;
if (vcc->dev->ops->send_bh)
vcc->send = vcc->dev->ops->send_bh;
else
vcc->send = vcc->dev->ops->send;
return 0;
}
int atm_init_aal5(struct atm_vcc *vcc)
{
vcc->push = atm_push_raw;
vcc->pop = atm_pop_raw;
vcc->push_oam = NULL;
if (vcc->dev->ops->send_bh)
vcc->send = vcc->dev->ops->send_bh;
else
vcc->send = vcc->dev->ops->send;
return 0;
}
EXPORT_SYMBOL(atm_init_aal5);