Commit Graph

209 Commits

Author SHA1 Message Date
Ilya Shchipletsov
a4fd163aed netrom: check buffer length before accessing it
Syzkaller reports an uninit value read from ax25cmp when sending raw message
through ieee802154 implementation.

=====================================================
BUG: KMSAN: uninit-value in ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119
 ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119
 nr_dev_get+0x20e/0x450 net/netrom/nr_route.c:601
 nr_route_frame+0x1a2/0xfc0 net/netrom/nr_route.c:774
 nr_xmit+0x5a/0x1c0 net/netrom/nr_dev.c:144
 __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3548 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3564
 __dev_queue_xmit+0x33b8/0x5130 net/core/dev.c:4349
 dev_queue_xmit include/linux/netdevice.h:3134 [inline]
 raw_sendmsg+0x654/0xc10 net/ieee802154/socket.c:299
 ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560
 __alloc_skb+0x318/0x740 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6334
 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2780
 sock_alloc_send_skb include/net/sock.h:1884 [inline]
 raw_sendmsg+0x36d/0xc10 net/ieee802154/socket.c:282
 ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 0 PID: 5037 Comm: syz-executor166 Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
=====================================================

This issue occurs because the skb buffer is too small, and it's actual
allocation is aligned. This hides an actual issue, which is that nr_route_frame
does not validate the buffer size before using it.

Fix this issue by checking skb->len before accessing any fields in skb->data.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Co-developed-by: Nikita Marushkin <hfggklm@gmail.com>
Signed-off-by: Nikita Marushkin <hfggklm@gmail.com>
Signed-off-by: Ilya Shchipletsov <rabbelkin@mail.ru>
Link: https://patch.msgid.link/20241219082308.3942-1-rabbelkin@mail.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-23 10:04:55 -08:00
Hongbo Li
597be7bd17 net/netrom: prefer strscpy over strcpy
The deprecated helper strcpy() performs no bounds checking on the
destination buffer. This could result in linear overflows beyond
the end of the buffer, leading to all kinds of misbehaviors.
The safe replacement is strscpy() [1].

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]

Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Link: https://patch.msgid.link/20240828123224.3697672-4-lihongbo22@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-29 12:33:07 -07:00
Gavrilov Ilia
0b9130247f netrom: Fix a memory leak in nr_heartbeat_expiry()
syzbot reported a memory leak in nr_create() [0].

Commit 409db27e3a ("netrom: Fix use-after-free of a listening socket.")
added sock_hold() to the nr_heartbeat_expiry() function, where
a) a socket has a SOCK_DESTROY flag or
b) a listening socket has a SOCK_DEAD flag.

But in the case "a," when the SOCK_DESTROY flag is set, the file descriptor
has already been closed and the nr_release() function has been called.
So it makes no sense to hold the reference count because no one will
call another nr_destroy_socket() and put it as in the case "b."

nr_connect
  nr_establish_data_link
    nr_start_heartbeat

nr_release
  switch (nr->state)
  case NR_STATE_3
    nr->state = NR_STATE_2
    sock_set_flag(sk, SOCK_DESTROY);

                        nr_rx_frame
                          nr_process_rx_frame
                            switch (nr->state)
                            case NR_STATE_2
                              nr_state2_machine()
                                nr_disconnect()
                                  nr_sk(sk)->state = NR_STATE_0
                                  sock_set_flag(sk, SOCK_DEAD)

                        nr_heartbeat_expiry
                          switch (nr->state)
                          case NR_STATE_0
                            if (sock_flag(sk, SOCK_DESTROY) ||
                               (sk->sk_state == TCP_LISTEN
                                 && sock_flag(sk, SOCK_DEAD)))
                               sock_hold()  // ( !!! )
                               nr_destroy_socket()

To fix the memory leak, let's call sock_hold() only for a listening socket.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with Syzkaller.

[0]: https://syzkaller.appspot.com/bug?extid=d327a1f3b12e1e206c16

Reported-by: syzbot+d327a1f3b12e1e206c16@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d327a1f3b12e1e206c16
Fixes: 409db27e3a ("netrom: Fix use-after-free of a listening socket.")
Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-17 13:06:23 +01:00
Linus Torvalds
89721e3038 Merge tag 'net-accept-more-20240515' of git://git.kernel.dk/linux
Pull more io_uring updates from Jens Axboe:
 "This adds support for IORING_CQE_F_SOCK_NONEMPTY for io_uring accept
  requests.

  This is very similar to previous work that enabled the same hint for
  doing receives on sockets. By far the majority of the work here is
  refactoring to enable the networking side to pass back whether or not
  the socket had more pending requests after accepting the current one,
  the last patch just wires it up for io_uring.

  Not only does this enable applications to know whether there are more
  connections to accept right now, it also enables smarter logic for
  io_uring multishot accept on whether to retry immediately or wait for
  a poll trigger"

* tag 'net-accept-more-20240515' of git://git.kernel.dk/linux:
  io_uring/net: wire up IORING_CQE_F_SOCK_NONEMPTY for accept
  net: pass back whether socket was empty post accept
  net: have do_accept() take a struct proto_accept_arg argument
  net: change proto and proto_ops accept type
2024-05-18 10:32:39 -07:00
Eric Dumazet
e03e7f20eb netrom: fix possible dead-lock in nr_rt_ioctl()
syzbot loves netrom, and found a possible deadlock in nr_rt_ioctl [1]

Make sure we always acquire nr_node_list_lock before nr_node_lock(nr_node)

[1]
WARNING: possible circular locking dependency detected
6.9.0-rc7-syzkaller-02147-g654de42f3fc6 #0 Not tainted
------------------------------------------------------
syz-executor350/5129 is trying to acquire lock:
 ffff8880186e2070 (&nr_node->node_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
 ffff8880186e2070 (&nr_node->node_lock){+...}-{2:2}, at: nr_node_lock include/net/netrom.h:152 [inline]
 ffff8880186e2070 (&nr_node->node_lock){+...}-{2:2}, at: nr_dec_obs net/netrom/nr_route.c:464 [inline]
 ffff8880186e2070 (&nr_node->node_lock){+...}-{2:2}, at: nr_rt_ioctl+0x1bb/0x1090 net/netrom/nr_route.c:697

but task is already holding lock:
 ffffffff8f7053b8 (nr_node_list_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
 ffffffff8f7053b8 (nr_node_list_lock){+...}-{2:2}, at: nr_dec_obs net/netrom/nr_route.c:462 [inline]
 ffffffff8f7053b8 (nr_node_list_lock){+...}-{2:2}, at: nr_rt_ioctl+0x10a/0x1090 net/netrom/nr_route.c:697

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (nr_node_list_lock){+...}-{2:2}:
        lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
        __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
        _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
        spin_lock_bh include/linux/spinlock.h:356 [inline]
        nr_remove_node net/netrom/nr_route.c:299 [inline]
        nr_del_node+0x4b4/0x820 net/netrom/nr_route.c:355
        nr_rt_ioctl+0xa95/0x1090 net/netrom/nr_route.c:683
        sock_do_ioctl+0x158/0x460 net/socket.c:1222
        sock_ioctl+0x629/0x8e0 net/socket.c:1341
        vfs_ioctl fs/ioctl.c:51 [inline]
        __do_sys_ioctl fs/ioctl.c:904 [inline]
        __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:890
        do_syscall_x64 arch/x86/entry/common.c:52 [inline]
        do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&nr_node->node_lock){+...}-{2:2}:
        check_prev_add kernel/locking/lockdep.c:3134 [inline]
        check_prevs_add kernel/locking/lockdep.c:3253 [inline]
        validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869
        __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
        lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
        __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
        _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
        spin_lock_bh include/linux/spinlock.h:356 [inline]
        nr_node_lock include/net/netrom.h:152 [inline]
        nr_dec_obs net/netrom/nr_route.c:464 [inline]
        nr_rt_ioctl+0x1bb/0x1090 net/netrom/nr_route.c:697
        sock_do_ioctl+0x158/0x460 net/socket.c:1222
        sock_ioctl+0x629/0x8e0 net/socket.c:1341
        vfs_ioctl fs/ioctl.c:51 [inline]
        __do_sys_ioctl fs/ioctl.c:904 [inline]
        __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:890
        do_syscall_x64 arch/x86/entry/common.c:52 [inline]
        do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(nr_node_list_lock);
                               lock(&nr_node->node_lock);
                               lock(nr_node_list_lock);
  lock(&nr_node->node_lock);

 *** DEADLOCK ***

1 lock held by syz-executor350/5129:
  #0: ffffffff8f7053b8 (nr_node_list_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
  #0: ffffffff8f7053b8 (nr_node_list_lock){+...}-{2:2}, at: nr_dec_obs net/netrom/nr_route.c:462 [inline]
  #0: ffffffff8f7053b8 (nr_node_list_lock){+...}-{2:2}, at: nr_rt_ioctl+0x10a/0x1090 net/netrom/nr_route.c:697

stack backtrace:
CPU: 0 PID: 5129 Comm: syz-executor350 Not tainted 6.9.0-rc7-syzkaller-02147-g654de42f3fc6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
  check_prev_add kernel/locking/lockdep.c:3134 [inline]
  check_prevs_add kernel/locking/lockdep.c:3253 [inline]
  validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869
  __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
  lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
  __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
  _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
  spin_lock_bh include/linux/spinlock.h:356 [inline]
  nr_node_lock include/net/netrom.h:152 [inline]
  nr_dec_obs net/netrom/nr_route.c:464 [inline]
  nr_rt_ioctl+0x1bb/0x1090 net/netrom/nr_route.c:697
  sock_do_ioctl+0x158/0x460 net/socket.c:1222
  sock_ioctl+0x629/0x8e0 net/socket.c:1341
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:904 [inline]
  __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:890
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240515142934.3708038-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-16 19:35:44 -07:00
Jens Axboe
92ef0fd55a net: change proto and proto_ops accept type
Rather than pass in flags, error pointer, and whether this is a kernel
invocation or not, add a struct proto_accept_arg struct as the argument.
This then holds all of these arguments, and prepares accept for being
able to pass back more information.

No functional changes in this patch.

Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-13 18:19:09 -06:00
Joel Granados
73dbd8cf79 net: Remove ctl_table sentinel elements from several networking subsystems
This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

To avoid lots of small commits, this commit brings together network
changes from (as they appear in MAINTAINERS) LLC, MPTCP, NETROM NETWORK
LAYER, PHONET PROTOCOL, ROSE NETWORK LAYER, RXRPC SOCKETS, SCTP
PROTOCOL, SHARED MEMORY COMMUNICATIONS (SMC), TIPC NETWORK LAYER and
NETWORKING [IPSEC]

* Remove sentinel element from ctl_table structs.
* Replace empty array registration with the register_net_sysctl_sz call
  in llc_sysctl_init
* Replace the for loop stop condition that tests for procname == NULL
  with one that depends on array size in sctp_sysctl_net_register
* Remove instances where an array element is zeroed out to make it look
  like a sentinel in xfrm_sysctl_init. This is not longer needed and is
  safe after commit c899710fe7 ("networking: Update to
  register_net_sysctl_sz") added the array size to the ctl_table
  registration
* Use a table_size variable to keep the value of ARRAY_SIZE

Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-03 13:29:42 +01:00
Jason Xing
d380ce7005 netrom: Fix data-races around sysctl_net_busy_read
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
bc76645ebd netrom: Fix a data-race around sysctl_netrom_link_fails_count
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
b5dffcb8f7 netrom: Fix a data-race around sysctl_netrom_routing_control
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
f99b494b40 netrom: Fix a data-race around sysctl_netrom_transport_no_activity_timeout
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
a2e7068414 netrom: Fix a data-race around sysctl_netrom_transport_requested_window_size
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
43547d8699 netrom: Fix a data-race around sysctl_netrom_transport_busy_delay
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
806f462ba9 netrom: Fix a data-race around sysctl_netrom_transport_acknowledge_delay
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
e799299aaf netrom: Fix a data-race around sysctl_netrom_transport_maximum_tries
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
60a7a152ab netrom: Fix a data-race around sysctl_netrom_transport_timeout
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
119cae5ea3 netrom: Fix data-races around sysctl_netrom_network_ttl_initialiser
We need to protect the reader reading the sysctl value because the
value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
cfd9f4a740 netrom: Fix a data-race around sysctl_netrom_obsolescence_count_initialiser
We need to protect the reader reading the sysctl value
because the value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Jason Xing
958d6145a6 netrom: Fix a data-race around sysctl_netrom_default_path_quality
We need to protect the reader reading sysctl_netrom_default_path_quality
because the value can be changed concurrently.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-07 10:36:58 +01:00
Eric Dumazet
10bbf1652c net: implement lockless SO_PRIORITY
This is a followup of 8bf43be799 ("net: annotate data-races
around sk->sk_priority").

sk->sk_priority can be read and written without holding the socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-01 19:09:54 +01:00
Kuniyuki Iwashima
c2f8fd7949 netrom: Deny concurrent connect().
syzkaller reported null-ptr-deref [0] related to AF_NETROM.
This is another self-accept issue from the strace log. [1]

syz-executor creates an AF_NETROM socket and calls connect(), which
is blocked at that time.  Then, sk->sk_state is TCP_SYN_SENT and
sock->state is SS_CONNECTING.

  [pid  5059] socket(AF_NETROM, SOCK_SEQPACKET, 0) = 4
  [pid  5059] connect(4, {sa_family=AF_NETROM, sa_data="..." <unfinished ...>

Another thread calls connect() concurrently, which finally fails
with -EINVAL.  However, the problem here is the socket state is
reset even while the first connect() is blocked.

  [pid  5060] connect(4, NULL, 0 <unfinished ...>
  [pid  5060] <... connect resumed>)      = -1 EINVAL (Invalid argument)

As sk->state is TCP_CLOSE and sock->state is SS_UNCONNECTED, the
following listen() succeeds.  Then, the first connect() looks up
itself as a listener and puts skb into the queue with skb->sk itself.
As a result, the next accept() gets another FD of itself as 3, and
the first connect() finishes.

  [pid  5060] listen(4, 0 <unfinished ...>
  [pid  5060] <... listen resumed>)       = 0
  [pid  5060] accept(4, NULL, NULL <unfinished ...>
  [pid  5060] <... accept resumed>)       = 3
  [pid  5059] <... connect resumed>)      = 0

Then, accept4() is called but blocked, which causes the general protection
fault later.

  [pid  5059] accept4(4, NULL, 0x20000400, SOCK_NONBLOCK <unfinished ...>

After that, another self-accept occurs by accept() and writev().

  [pid  5060] accept(4, NULL, NULL <unfinished ...>
  [pid  5061] writev(3, [{iov_base=...}] <unfinished ...>
  [pid  5061] <... writev resumed>)       = 99
  [pid  5060] <... accept resumed>)       = 6

Finally, the leader thread close()s all FDs.  Since the three FDs
reference the same socket, nr_release() does the cleanup for it
three times, and the remaining accept4() causes the following fault.

  [pid  5058] close(3)                    = 0
  [pid  5058] close(4)                    = 0
  [pid  5058] close(5)                    = -1 EBADF (Bad file descriptor)
  [pid  5058] close(6)                    = 0
  [pid  5058] <... exit_group resumed>)   = ?
  [   83.456055][ T5059] general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN

To avoid the issue, we need to return an error for connect() if
another connect() is in progress, as done in __inet_stream_connect().

[0]:
general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 0 PID: 5059 Comm: syz-executor.0 Not tainted 6.5.0-rc5-syzkaller-00194-gace0ab3a4b54 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:__lock_acquire+0x109/0x5de0 kernel/locking/lockdep.c:5012
Code: 45 85 c9 0f 84 cc 0e 00 00 44 8b 05 11 6e 23 0b 45 85 c0 0f 84 be 0d 00 00 48 ba 00 00 00 00 00 fc ff df 4c 89 d1 48 c1 e9 03 <80> 3c 11 00 0f 85 e8 40 00 00 49 81 3a a0 69 48 90 0f 84 96 0d 00
RSP: 0018:ffffc90003d6f9e0 EFLAGS: 00010006
RAX: ffff8880244c8000 RBX: 1ffff920007adf6c RCX: 0000000000000003
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000018
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000018 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f51d519a6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f51d5158d58 CR3: 000000002943f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire kernel/locking/lockdep.c:5761 [inline]
 lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
 prepare_to_wait+0x47/0x380 kernel/sched/wait.c:269
 nr_accept+0x20d/0x650 net/netrom/af_netrom.c:798
 do_accept+0x3a6/0x570 net/socket.c:1872
 __sys_accept4_file net/socket.c:1913 [inline]
 __sys_accept4+0x99/0x120 net/socket.c:1943
 __do_sys_accept4 net/socket.c:1954 [inline]
 __se_sys_accept4 net/socket.c:1951 [inline]
 __x64_sys_accept4+0x96/0x100 net/socket.c:1951
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f51d447cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f51d519a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000120
RAX: ffffffffffffffda RBX: 00007f51d459bf80 RCX: 00007f51d447cae9
RDX: 0000000020000400 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f51d44c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000800 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f51d459bf80 R15: 00007ffc25c34e48
 </TASK>

Link: https://syzkaller.appspot.com/text?tag=CrashLog&x=152cdb63a80000 [1]
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+666c97e4686410e79649@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=666c97e4686410e79649
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-28 06:58:46 +01:00
David Howells
dc97391e66 sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)
Remove ->sendpage() and ->sendpage_locked().  sendmsg() with
MSG_SPLICE_PAGES should be used instead.  This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-24 15:50:13 -07:00
Eric Dumazet
31642e7089 netrom: fix info-leak in nr_write_internal()
Simon Kapadia reported the following issue:

<quote>

The Online Amateur Radio Community (OARC) has recently been experimenting
with building a nationwide packet network in the UK.
As part of our experimentation, we have been testing out packet on 300bps HF,
and playing with net/rom.  For HF packet at this baud rate you really need
to make sure that your MTU is relatively low; AX.25 suggests a PACLEN of 60,
and a net/rom PACLEN of 40 to go with that.
However the Linux net/rom support didn't work with a low PACLEN;
the mkiss module would truncate packets if you set the PACLEN below about 200 or so, e.g.:

Apr 19 14:00:51 radio kernel: [12985.747310] mkiss: ax1: truncating oversized transmit packet!

This didn't make any sense to me (if the packets are smaller why would they
be truncated?) so I started investigating.
I looked at the packets using ethereal, and found that many were just huge
compared to what I would expect.
A simple net/rom connection request packet had the request and then a bunch
of what appeared to be random data following it:

</quote>

Simon provided a patch that I slightly revised:
Not only we must not use skb_tailroom(), we also do
not want to count NR_NETWORK_LEN twice.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Co-Developed-by: Simon Kapadia <szymon@kapadia.pl>
Signed-off-by: Simon Kapadia <szymon@kapadia.pl>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Simon Kapadia <szymon@kapadia.pl>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230524141456.1045467-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-25 21:02:29 -07:00
Hyunwoo Kim
6117929209 netrom: Fix use-after-free caused by accept on already connected socket
If you call listen() and accept() on an already connect()ed
AF_NETROM socket, accept() can successfully connect.
This is because when the peer socket sends data to sendmsg,
the skb with its own sk stored in the connected socket's
sk->sk_receive_queue is connected, and nr_accept() dequeues
the skb waiting in the sk->sk_receive_queue.

As a result, nr_accept() allocates and returns a sock with
the sk of the parent AF_NETROM socket.

And here use-after-free can happen through complex race conditions:
```
                  cpu0                                                     cpu1
                                                               1. socket_2 = socket(AF_NETROM)
                                                                        .
                                                                        .
                                                                  listen(socket_2)
                                                                  accepted_socket = accept(socket_2)
       2. socket_1 = socket(AF_NETROM)
            nr_create()    // sk refcount : 1
          connect(socket_1)
                                                               3. write(accepted_socket)
                                                                    nr_sendmsg()
                                                                    nr_output()
                                                                    nr_kick()
                                                                    nr_send_iframe()
                                                                    nr_transmit_buffer()
                                                                    nr_route_frame()
                                                                    nr_loopback_queue()
                                                                    nr_loopback_timer()
                                                                    nr_rx_frame()
                                                                    nr_process_rx_frame(sk, skb);    // sk : socket_1's sk
                                                                    nr_state3_machine()
                                                                    nr_queue_rx_frame()
                                                                    sock_queue_rcv_skb()
                                                                    sock_queue_rcv_skb_reason()
                                                                    __sock_queue_rcv_skb()
                                                                    __skb_queue_tail(list, skb);    // list : socket_1's sk->sk_receive_queue
       4. listen(socket_1)
            nr_listen()
          uaf_socket = accept(socket_1)
            nr_accept()
            skb_dequeue(&sk->sk_receive_queue);
                                                               5. close(accepted_socket)
                                                                    nr_release()
                                                                    nr_write_internal(sk, NR_DISCREQ)
                                                                    nr_transmit_buffer()    // NR_DISCREQ
                                                                    nr_route_frame()
                                                                    nr_loopback_queue()
                                                                    nr_loopback_timer()
                                                                    nr_rx_frame()    // sk : socket_1's sk
                                                                    nr_process_rx_frame()  // NR_STATE_3
                                                                    nr_state3_machine()    // NR_DISCREQ
                                                                    nr_disconnect()
                                                                    nr_sk(sk)->state = NR_STATE_0;
       6. close(socket_1)    // sk refcount : 3
            nr_release()    // NR_STATE_0
            sock_put(sk);    // sk refcount : 0
            sk_free(sk);
          close(uaf_socket)
            nr_release()
            sock_hold(sk);    // UAF
```

KASAN report by syzbot:
```
BUG: KASAN: use-after-free in nr_release+0x66/0x460 net/netrom/af_netrom.c:520
Write of size 4 at addr ffff8880235d8080 by task syz-executor564/5128

Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:306 [inline]
 print_report+0x15e/0x461 mm/kasan/report.c:417
 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x141/0x190 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 sock_hold include/net/sock.h:775 [inline]
 nr_release+0x66/0x460 net/netrom/af_netrom.c:520
 __sock_release+0xcd/0x280 net/socket.c:650
 sock_close+0x1c/0x20 net/socket.c:1365
 __fput+0x27c/0xa90 fs/file_table.c:320
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xaa8/0x2950 kernel/exit.c:867
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012
 get_signal+0x21c3/0x2450 kernel/signal.c:2859
 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f6c19e3c9b9
Code: Unable to access opcode bytes at 0x7f6c19e3c98f.
RSP: 002b:00007fffd4ba2ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: 0000000000000116 RBX: 0000000000000003 RCX: 00007f6c19e3c9b9
RDX: 0000000000000318 RSI: 00000000200bd000 RDI: 0000000000000006
RBP: 0000000000000003 R08: 000000000000000d R09: 000000000000000d
R10: 0000000000000000 R11: 0000000000000246 R12: 000055555566a2c0
R13: 0000000000000011 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 5128:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:371 [inline]
 ____kasan_kmalloc mm/kasan/common.c:330 [inline]
 __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:380
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:968 [inline]
 __kmalloc+0x5a/0xd0 mm/slab_common.c:981
 kmalloc include/linux/slab.h:584 [inline]
 sk_prot_alloc+0x140/0x290 net/core/sock.c:2038
 sk_alloc+0x3a/0x7a0 net/core/sock.c:2091
 nr_create+0xb6/0x5f0 net/netrom/af_netrom.c:433
 __sock_create+0x359/0x790 net/socket.c:1515
 sock_create net/socket.c:1566 [inline]
 __sys_socket_create net/socket.c:1603 [inline]
 __sys_socket_create net/socket.c:1588 [inline]
 __sys_socket+0x133/0x250 net/socket.c:1636
 __do_sys_socket net/socket.c:1649 [inline]
 __se_sys_socket net/socket.c:1647 [inline]
 __x64_sys_socket+0x73/0xb0 net/socket.c:1647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 5128:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:518
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:177 [inline]
 __cache_free mm/slab.c:3394 [inline]
 __do_kmem_cache_free mm/slab.c:3580 [inline]
 __kmem_cache_free+0xcd/0x3b0 mm/slab.c:3587
 sk_prot_free net/core/sock.c:2074 [inline]
 __sk_destruct+0x5df/0x750 net/core/sock.c:2166
 sk_destruct net/core/sock.c:2181 [inline]
 __sk_free+0x175/0x460 net/core/sock.c:2192
 sk_free+0x7c/0xa0 net/core/sock.c:2203
 sock_put include/net/sock.h:1991 [inline]
 nr_release+0x39e/0x460 net/netrom/af_netrom.c:554
 __sock_release+0xcd/0x280 net/socket.c:650
 sock_close+0x1c/0x20 net/socket.c:1365
 __fput+0x27c/0xa90 fs/file_table.c:320
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xaa8/0x2950 kernel/exit.c:867
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012
 get_signal+0x21c3/0x2450 kernel/signal.c:2859
 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
```

To fix this issue, nr_listen() returns -EINVAL for sockets that
successfully nr_connect().

Reported-by: syzbot+caa188bdfc1eeafeb418@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Hyunwoo Kim <v4bel@theori.io>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-30 07:30:47 +00:00
Kuniyuki Iwashima
409db27e3a netrom: Fix use-after-free of a listening socket.
syzbot reported a use-after-free in do_accept(), precisely nr_accept()
as sk_prot_alloc() allocated the memory and sock_put() frees it. [0]

The issue could happen if the heartbeat timer is fired and
nr_heartbeat_expiry() calls nr_destroy_socket(), where a socket
has SOCK_DESTROY or a listening socket has SOCK_DEAD.

In this case, the first condition cannot be true.  SOCK_DESTROY is
flagged in nr_release() only when the file descriptor is close()d,
but accept() is being called for the listening socket, so the second
condition must be true.

Usually, the AF_NETROM listener neither starts timers nor sets
SOCK_DEAD.  However, the condition is met if connect() fails before
listen().  connect() starts the t1 timer and heartbeat timer, and
t1timer calls nr_disconnect() when timeout happens.  Then, SOCK_DEAD
is set, and if we call listen(), the heartbeat timer calls
nr_destroy_socket().

  nr_connect
    nr_establish_data_link(sk)
      nr_start_t1timer(sk)
    nr_start_heartbeat(sk)
                                    nr_t1timer_expiry
                                      nr_disconnect(sk, ETIMEDOUT)
                                        nr_sk(sk)->state = NR_STATE_0
                                        sk->sk_state = TCP_CLOSE
                                        sock_set_flag(sk, SOCK_DEAD)
nr_listen
  if (sk->sk_state != TCP_LISTEN)
    sk->sk_state = TCP_LISTEN
                                    nr_heartbeat_expiry
                                      switch (nr->state)
                                      case NR_STATE_0
                                        if (sk->sk_state == TCP_LISTEN &&
                                            sock_flag(sk, SOCK_DEAD))
                                          nr_destroy_socket(sk)

This path seems expected, and nr_destroy_socket() is called to clean
up resources.  Initially, there was sock_hold() before nr_destroy_socket()
so that the socket would not be freed, but the commit 517a16b1a8
("netrom: Decrease sock refcount when sock timers expire") accidentally
removed it.

To fix use-after-free, let's add sock_hold().

[0]:
BUG: KASAN: use-after-free in do_accept+0x483/0x510 net/socket.c:1848
Read of size 8 at addr ffff88807978d398 by task syz-executor.3/5315

CPU: 0 PID: 5315 Comm: syz-executor.3 Not tainted 6.2.0-rc3-syzkaller-00165-gd9fc1511728c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:306 [inline]
 print_report+0x15e/0x461 mm/kasan/report.c:417
 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517
 do_accept+0x483/0x510 net/socket.c:1848
 __sys_accept4_file net/socket.c:1897 [inline]
 __sys_accept4+0x9a/0x120 net/socket.c:1927
 __do_sys_accept net/socket.c:1944 [inline]
 __se_sys_accept net/socket.c:1941 [inline]
 __x64_sys_accept+0x75/0xb0 net/socket.c:1941
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fa436a8c0c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa437784168 EFLAGS: 00000246 ORIG_RAX: 000000000000002b
RAX: ffffffffffffffda RBX: 00007fa436bac050 RCX: 00007fa436a8c0c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007fa436ae7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffebc6700df R14: 00007fa437784300 R15: 0000000000022000
 </TASK>

Allocated by task 5294:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:371 [inline]
 ____kasan_kmalloc mm/kasan/common.c:330 [inline]
 __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:380
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:968 [inline]
 __kmalloc+0x5a/0xd0 mm/slab_common.c:981
 kmalloc include/linux/slab.h:584 [inline]
 sk_prot_alloc+0x140/0x290 net/core/sock.c:2038
 sk_alloc+0x3a/0x7a0 net/core/sock.c:2091
 nr_create+0xb6/0x5f0 net/netrom/af_netrom.c:433
 __sock_create+0x359/0x790 net/socket.c:1515
 sock_create net/socket.c:1566 [inline]
 __sys_socket_create net/socket.c:1603 [inline]
 __sys_socket_create net/socket.c:1588 [inline]
 __sys_socket+0x133/0x250 net/socket.c:1636
 __do_sys_socket net/socket.c:1649 [inline]
 __se_sys_socket net/socket.c:1647 [inline]
 __x64_sys_socket+0x73/0xb0 net/socket.c:1647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 14:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:518
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:177 [inline]
 __cache_free mm/slab.c:3394 [inline]
 __do_kmem_cache_free mm/slab.c:3580 [inline]
 __kmem_cache_free+0xcd/0x3b0 mm/slab.c:3587
 sk_prot_free net/core/sock.c:2074 [inline]
 __sk_destruct+0x5df/0x750 net/core/sock.c:2166
 sk_destruct net/core/sock.c:2181 [inline]
 __sk_free+0x175/0x460 net/core/sock.c:2192
 sk_free+0x7c/0xa0 net/core/sock.c:2203
 sock_put include/net/sock.h:1991 [inline]
 nr_heartbeat_expiry+0x1d7/0x460 net/netrom/nr_timer.c:148
 call_timer_fn+0x1da/0x7c0 kernel/time/timer.c:1700
 expire_timers+0x2c6/0x5c0 kernel/time/timer.c:1751
 __run_timers kernel/time/timer.c:2022 [inline]
 __run_timers kernel/time/timer.c:1995 [inline]
 run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
 __do_softirq+0x1fb/0xadc kernel/softirq.c:571

Fixes: 517a16b1a8 ("netrom: Decrease sock refcount when sock timers expire")
Reported-by: syzbot+5fafd5cfe1fc91f6b352@syzkaller.appspotmail.com
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230120231927.51711-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-01-24 11:54:01 +01:00