linux/net/nfc/rawsock.c
Eric Dumazet 03e934f620 NFC: Return from rawsock_release when sk is NULL
Sasha Levin reported following panic :

[ 2136.383310] BUG: unable to handle kernel NULL pointer dereference at
00000000000003b0
[ 2136.384022] IP: [<ffffffff8114e400>] __lock_acquire+0xc0/0x4b0
[ 2136.384022] PGD 131c4067 PUD 11c0c067 PMD 0
[ 2136.388106] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 2136.388106] CPU 1
[ 2136.388106] Pid: 24855, comm: trinity-child1 Tainted: G        W
3.5.0-rc2-sasha-00015-g7b268f7 #374
[ 2136.388106] RIP: 0010:[<ffffffff8114e400>]  [<ffffffff8114e400>]
__lock_acquire+0xc0/0x4b0
[ 2136.388106] RSP: 0018:ffff8800130b3ca8  EFLAGS: 00010046
[ 2136.388106] RAX: 0000000000000086 RBX: ffff88001186b000 RCX:
0000000000000000
[ 2136.388106] RDX: 0000000000000000 RSI: 0000000000000000 RDI:
0000000000000000
[ 2136.388106] RBP: ffff8800130b3d08 R08: 0000000000000001 R09:
0000000000000000
[ 2136.388106] R10: 0000000000000000 R11: 0000000000000001 R12:
0000000000000002
[ 2136.388106] R13: 00000000000003b0 R14: 0000000000000000 R15:
0000000000000000
[ 2136.388106] FS:  00007fa5b1bd4700(0000) GS:ffff88001b800000(0000)
knlGS:0000000000000000
[ 2136.388106] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2136.388106] CR2: 00000000000003b0 CR3: 0000000011d1f000 CR4:
00000000000406e0
[ 2136.388106] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 2136.388106] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[ 2136.388106] Process trinity-child1 (pid: 24855, threadinfo
ffff8800130b2000, task ffff88001186b000)
[ 2136.388106] Stack:
[ 2136.388106]  ffff8800130b3cd8 ffffffff81121785 ffffffff81236774
000080d000000001
[ 2136.388106]  ffff88001b9d6c00 00000000001d6c00 ffffffff130b3d08
ffff88001186b000
[ 2136.388106]  0000000000000000 0000000000000002 0000000000000000
0000000000000000
[ 2136.388106] Call Trace:
[ 2136.388106]  [<ffffffff81121785>] ? sched_clock_local+0x25/0x90
[ 2136.388106]  [<ffffffff81236774>] ? get_empty_filp+0x74/0x220
[ 2136.388106]  [<ffffffff8114e97a>] lock_acquire+0x18a/0x1e0
[ 2136.388106]  [<ffffffff836b37df>] ? rawsock_release+0x4f/0xa0
[ 2136.388106]  [<ffffffff837c0ef0>] _raw_write_lock_bh+0x40/0x80
[ 2136.388106]  [<ffffffff836b37df>] ? rawsock_release+0x4f/0xa0
[ 2136.388106]  [<ffffffff836b37df>] rawsock_release+0x4f/0xa0
[ 2136.388106]  [<ffffffff8321cfe8>] sock_release+0x18/0x70
[ 2136.388106]  [<ffffffff8321d069>] sock_close+0x29/0x30
[ 2136.388106]  [<ffffffff81236bca>] __fput+0x11a/0x2c0
[ 2136.388106]  [<ffffffff81236d85>] fput+0x15/0x20
[ 2136.388106]  [<ffffffff8321de34>] sys_accept4+0x1b4/0x200
[ 2136.388106]  [<ffffffff837c165c>] ? _raw_spin_unlock_irq+0x4c/0x80
[ 2136.388106]  [<ffffffff837c1669>] ? _raw_spin_unlock_irq+0x59/0x80
[ 2136.388106]  [<ffffffff837c2565>] ? sysret_check+0x22/0x5d
[ 2136.388106]  [<ffffffff8321de8b>] sys_accept+0xb/0x10
[ 2136.388106]  [<ffffffff837c2539>] system_call_fastpath+0x16/0x1b
[ 2136.388106] Code: ec 04 00 0f 85 ea 03 00 00 be d5 0b 00 00 48 c7 c7
8a c1 40 84 e8 b1 a5 f8 ff 31 c0 e9 d4 03 00 00 66 2e 0f 1f 84 00 00 00
00 00 <49> 81 7d 00 60 73 5e 85 b8 01 00 00 00 44 0f 44 e0 83 fe 01 77
[ 2136.388106] RIP  [<ffffffff8114e400>] __lock_acquire+0xc0/0x4b0
[ 2136.388106]  RSP <ffff8800130b3ca8>
[ 2136.388106] CR2: 00000000000003b0
[ 2136.388106] ---[ end trace 6d450e935ee18982 ]---
[ 2136.388106] Kernel panic - not syncing: Fatal exception in interrupt

rawsock_release() should test if sock->sk is NULL before calling
sock_orphan()/sock_put()

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2012-06-26 01:35:26 +02:00

351 lines
7.6 KiB
C

/*
* Copyright (C) 2011 Instituto Nokia de Tecnologia
*
* Authors:
* Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
* Lauro Ramos Venancio <lauro.venancio@openbossa.org>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
#include <net/tcp_states.h>
#include <linux/nfc.h>
#include <linux/export.h>
#include "nfc.h"
static void rawsock_write_queue_purge(struct sock *sk)
{
pr_debug("sk=%p\n", sk);
spin_lock_bh(&sk->sk_write_queue.lock);
__skb_queue_purge(&sk->sk_write_queue);
nfc_rawsock(sk)->tx_work_scheduled = false;
spin_unlock_bh(&sk->sk_write_queue.lock);
}
static void rawsock_report_error(struct sock *sk, int err)
{
pr_debug("sk=%p err=%d\n", sk, err);
sk->sk_shutdown = SHUTDOWN_MASK;
sk->sk_err = -err;
sk->sk_error_report(sk);
rawsock_write_queue_purge(sk);
}
static int rawsock_release(struct socket *sock)
{
struct sock *sk = sock->sk;
pr_debug("sock=%p sk=%p\n", sock, sk);
if (!sk)
return 0;
sock_orphan(sk);
sock_put(sk);
return 0;
}
static int rawsock_connect(struct socket *sock, struct sockaddr *_addr,
int len, int flags)
{
struct sock *sk = sock->sk;
struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr;
struct nfc_dev *dev;
int rc = 0;
pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags);
if (!addr || len < sizeof(struct sockaddr_nfc) ||
addr->sa_family != AF_NFC)
return -EINVAL;
pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n",
addr->dev_idx, addr->target_idx, addr->nfc_protocol);
lock_sock(sk);
if (sock->state == SS_CONNECTED) {
rc = -EISCONN;
goto error;
}
dev = nfc_get_device(addr->dev_idx);
if (!dev) {
rc = -ENODEV;
goto error;
}
if (addr->target_idx > dev->target_next_idx - 1 ||
addr->target_idx < dev->target_next_idx - dev->n_targets) {
rc = -EINVAL;
goto error;
}
rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol);
if (rc)
goto put_dev;
nfc_rawsock(sk)->dev = dev;
nfc_rawsock(sk)->target_idx = addr->target_idx;
sock->state = SS_CONNECTED;
sk->sk_state = TCP_ESTABLISHED;
sk->sk_state_change(sk);
release_sock(sk);
return 0;
put_dev:
nfc_put_device(dev);
error:
release_sock(sk);
return rc;
}
static int rawsock_add_header(struct sk_buff *skb)
{
*skb_push(skb, NFC_HEADER_SIZE) = 0;
return 0;
}
static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb,
int err)
{
struct sock *sk = (struct sock *) context;
BUG_ON(in_irq());
pr_debug("sk=%p err=%d\n", sk, err);
if (err)
goto error;
err = rawsock_add_header(skb);
if (err)
goto error;
err = sock_queue_rcv_skb(sk, skb);
if (err)
goto error;
spin_lock_bh(&sk->sk_write_queue.lock);
if (!skb_queue_empty(&sk->sk_write_queue))
schedule_work(&nfc_rawsock(sk)->tx_work);
else
nfc_rawsock(sk)->tx_work_scheduled = false;
spin_unlock_bh(&sk->sk_write_queue.lock);
sock_put(sk);
return;
error:
rawsock_report_error(sk, err);
sock_put(sk);
}
static void rawsock_tx_work(struct work_struct *work)
{
struct sock *sk = to_rawsock_sk(work);
struct nfc_dev *dev = nfc_rawsock(sk)->dev;
u32 target_idx = nfc_rawsock(sk)->target_idx;
struct sk_buff *skb;
int rc;
pr_debug("sk=%p target_idx=%u\n", sk, target_idx);
if (sk->sk_shutdown & SEND_SHUTDOWN) {
rawsock_write_queue_purge(sk);
return;
}
skb = skb_dequeue(&sk->sk_write_queue);
sock_hold(sk);
rc = nfc_data_exchange(dev, target_idx, skb,
rawsock_data_exchange_complete, sk);
if (rc) {
rawsock_report_error(sk, rc);
sock_put(sk);
}
}
static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct nfc_dev *dev = nfc_rawsock(sk)->dev;
struct sk_buff *skb;
int rc;
pr_debug("sock=%p sk=%p len=%zu\n", sock, sk, len);
if (msg->msg_namelen)
return -EOPNOTSUPP;
if (sock->state != SS_CONNECTED)
return -ENOTCONN;
skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc);
if (skb == NULL)
return rc;
rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
if (rc < 0) {
kfree_skb(skb);
return rc;
}
spin_lock_bh(&sk->sk_write_queue.lock);
__skb_queue_tail(&sk->sk_write_queue, skb);
if (!nfc_rawsock(sk)->tx_work_scheduled) {
schedule_work(&nfc_rawsock(sk)->tx_work);
nfc_rawsock(sk)->tx_work_scheduled = true;
}
spin_unlock_bh(&sk->sk_write_queue.lock);
return len;
}
static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len, int flags)
{
int noblock = flags & MSG_DONTWAIT;
struct sock *sk = sock->sk;
struct sk_buff *skb;
int copied;
int rc;
pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags);
skb = skb_recv_datagram(sk, flags, noblock, &rc);
if (!skb)
return rc;
msg->msg_namelen = 0;
copied = skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
skb_free_datagram(sk, skb);
return rc ? : copied;
}
static const struct proto_ops rawsock_ops = {
.family = PF_NFC,
.owner = THIS_MODULE,
.release = rawsock_release,
.bind = sock_no_bind,
.connect = rawsock_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = sock_no_getname,
.poll = datagram_poll,
.ioctl = sock_no_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.setsockopt = sock_no_setsockopt,
.getsockopt = sock_no_getsockopt,
.sendmsg = rawsock_sendmsg,
.recvmsg = rawsock_recvmsg,
.mmap = sock_no_mmap,
};
static void rawsock_destruct(struct sock *sk)
{
pr_debug("sk=%p\n", sk);
if (sk->sk_state == TCP_ESTABLISHED) {
nfc_deactivate_target(nfc_rawsock(sk)->dev,
nfc_rawsock(sk)->target_idx);
nfc_put_device(nfc_rawsock(sk)->dev);
}
skb_queue_purge(&sk->sk_receive_queue);
if (!sock_flag(sk, SOCK_DEAD)) {
pr_err("Freeing alive NFC raw socket %p\n", sk);
return;
}
}
static int rawsock_create(struct net *net, struct socket *sock,
const struct nfc_protocol *nfc_proto)
{
struct sock *sk;
pr_debug("sock=%p\n", sock);
if (sock->type != SOCK_SEQPACKET)
return -ESOCKTNOSUPPORT;
sock->ops = &rawsock_ops;
sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto);
if (!sk)
return -ENOMEM;
sock_init_data(sock, sk);
sk->sk_protocol = nfc_proto->id;
sk->sk_destruct = rawsock_destruct;
sock->state = SS_UNCONNECTED;
INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work);
nfc_rawsock(sk)->tx_work_scheduled = false;
return 0;
}
static struct proto rawsock_proto = {
.name = "NFC_RAW",
.owner = THIS_MODULE,
.obj_size = sizeof(struct nfc_rawsock),
};
static const struct nfc_protocol rawsock_nfc_proto = {
.id = NFC_SOCKPROTO_RAW,
.proto = &rawsock_proto,
.owner = THIS_MODULE,
.create = rawsock_create
};
int __init rawsock_init(void)
{
int rc;
rc = nfc_proto_register(&rawsock_nfc_proto);
return rc;
}
void rawsock_exit(void)
{
nfc_proto_unregister(&rawsock_nfc_proto);
}