<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/nfc, branch linux-5.17.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>NFC: NULL out the dev-&gt;rfkill to prevent UAF</title>
<updated>2022-06-09T08:25:39+00:00</updated>
<author>
<name>Lin Ma</name>
<email>linma@zju.edu.cn</email>
</author>
<published>2022-04-12T05:32:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4a68938f43b7c2663e4c90bb9bbe29ac8b9a42a0'/>
<id>4a68938f43b7c2663e4c90bb9bbe29ac8b9a42a0</id>
<content type='text'>
[ Upstream commit 1b0e81416a24d6e9b8c2341e22e8bf48f8b8bfc9 ]

Commit 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device")
assumes the device_is_registered() in function nfc_dev_up() will help
to check when the rfkill is unregistered. However, this check only
take effect when device_del(&amp;dev-&gt;dev) is done in nfc_unregister_device().
Hence, the rfkill object is still possible be dereferenced.

The crash trace in latest kernel (5.18-rc2):

[   68.760105] ==================================================================
[   68.760330] BUG: KASAN: use-after-free in __lock_acquire+0x3ec1/0x6750
[   68.760756] Read of size 8 at addr ffff888009c93018 by task fuzz/313
[   68.760756]
[   68.760756] CPU: 0 PID: 313 Comm: fuzz Not tainted 5.18.0-rc2 #4
[   68.760756] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[   68.760756] Call Trace:
[   68.760756]  &lt;TASK&gt;
[   68.760756]  dump_stack_lvl+0x57/0x7d
[   68.760756]  print_report.cold+0x5e/0x5db
[   68.760756]  ? __lock_acquire+0x3ec1/0x6750
[   68.760756]  kasan_report+0xbe/0x1c0
[   68.760756]  ? __lock_acquire+0x3ec1/0x6750
[   68.760756]  __lock_acquire+0x3ec1/0x6750
[   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   68.760756]  ? register_lock_class+0x18d0/0x18d0
[   68.760756]  lock_acquire+0x1ac/0x4f0
[   68.760756]  ? rfkill_blocked+0xe/0x60
[   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   68.760756]  ? mutex_lock_io_nested+0x12c0/0x12c0
[   68.760756]  ? nla_get_range_signed+0x540/0x540
[   68.760756]  ? _raw_spin_lock_irqsave+0x4e/0x50
[   68.760756]  _raw_spin_lock_irqsave+0x39/0x50
[   68.760756]  ? rfkill_blocked+0xe/0x60
[   68.760756]  rfkill_blocked+0xe/0x60
[   68.760756]  nfc_dev_up+0x84/0x260
[   68.760756]  nfc_genl_dev_up+0x90/0xe0
[   68.760756]  genl_family_rcv_msg_doit+0x1f4/0x2f0
[   68.760756]  ? genl_family_rcv_msg_attrs_parse.constprop.0+0x230/0x230
[   68.760756]  ? security_capable+0x51/0x90
[   68.760756]  genl_rcv_msg+0x280/0x500
[   68.760756]  ? genl_get_cmd+0x3c0/0x3c0
[   68.760756]  ? lock_acquire+0x1ac/0x4f0
[   68.760756]  ? nfc_genl_dev_down+0xe0/0xe0
[   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   68.760756]  netlink_rcv_skb+0x11b/0x340
[   68.760756]  ? genl_get_cmd+0x3c0/0x3c0
[   68.760756]  ? netlink_ack+0x9c0/0x9c0
[   68.760756]  ? netlink_deliver_tap+0x136/0xb00
[   68.760756]  genl_rcv+0x1f/0x30
[   68.760756]  netlink_unicast+0x430/0x710
[   68.760756]  ? memset+0x20/0x40
[   68.760756]  ? netlink_attachskb+0x740/0x740
[   68.760756]  ? __build_skb_around+0x1f4/0x2a0
[   68.760756]  netlink_sendmsg+0x75d/0xc00
[   68.760756]  ? netlink_unicast+0x710/0x710
[   68.760756]  ? netlink_unicast+0x710/0x710
[   68.760756]  sock_sendmsg+0xdf/0x110
[   68.760756]  __sys_sendto+0x19e/0x270
[   68.760756]  ? __ia32_sys_getpeername+0xa0/0xa0
[   68.760756]  ? fd_install+0x178/0x4c0
[   68.760756]  ? fd_install+0x195/0x4c0
[   68.760756]  ? kernel_fpu_begin_mask+0x1c0/0x1c0
[   68.760756]  __x64_sys_sendto+0xd8/0x1b0
[   68.760756]  ? lockdep_hardirqs_on+0xbf/0x130
[   68.760756]  ? syscall_enter_from_user_mode+0x1d/0x50
[   68.760756]  do_syscall_64+0x3b/0x90
[   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   68.760756] RIP: 0033:0x7f67fb50e6b3
...
[   68.760756] RSP: 002b:00007f67fa91fe90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
[   68.760756] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f67fb50e6b3
[   68.760756] RDX: 000000000000001c RSI: 0000559354603090 RDI: 0000000000000003
[   68.760756] RBP: 00007f67fa91ff00 R08: 00007f67fa91fedc R09: 000000000000000c
[   68.760756] R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe824d496e
[   68.760756] R13: 00007ffe824d496f R14: 00007f67fa120000 R15: 0000000000000003

[   68.760756]  &lt;/TASK&gt;
[   68.760756]
[   68.760756] Allocated by task 279:
[   68.760756]  kasan_save_stack+0x1e/0x40
[   68.760756]  __kasan_kmalloc+0x81/0xa0
[   68.760756]  rfkill_alloc+0x7f/0x280
[   68.760756]  nfc_register_device+0xa3/0x1a0
[   68.760756]  nci_register_device+0x77a/0xad0
[   68.760756]  nfcmrvl_nci_register_dev+0x20b/0x2c0
[   68.760756]  nfcmrvl_nci_uart_open+0xf2/0x1dd
[   68.760756]  nci_uart_tty_ioctl+0x2c3/0x4a0
[   68.760756]  tty_ioctl+0x764/0x1310
[   68.760756]  __x64_sys_ioctl+0x122/0x190
[   68.760756]  do_syscall_64+0x3b/0x90
[   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   68.760756]
[   68.760756] Freed by task 314:
[   68.760756]  kasan_save_stack+0x1e/0x40
[   68.760756]  kasan_set_track+0x21/0x30
[   68.760756]  kasan_set_free_info+0x20/0x30
[   68.760756]  __kasan_slab_free+0x108/0x170
[   68.760756]  kfree+0xb0/0x330
[   68.760756]  device_release+0x96/0x200
[   68.760756]  kobject_put+0xf9/0x1d0
[   68.760756]  nfc_unregister_device+0x77/0x190
[   68.760756]  nfcmrvl_nci_unregister_dev+0x88/0xd0
[   68.760756]  nci_uart_tty_close+0xdf/0x180
[   68.760756]  tty_ldisc_kill+0x73/0x110
[   68.760756]  tty_ldisc_hangup+0x281/0x5b0
[   68.760756]  __tty_hangup.part.0+0x431/0x890
[   68.760756]  tty_release+0x3a8/0xc80
[   68.760756]  __fput+0x1f0/0x8c0
[   68.760756]  task_work_run+0xc9/0x170
[   68.760756]  exit_to_user_mode_prepare+0x194/0x1a0
[   68.760756]  syscall_exit_to_user_mode+0x19/0x50
[   68.760756]  do_syscall_64+0x48/0x90
[   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae

This patch just add the null out of dev-&gt;rfkill to make sure such
dereference cannot happen. This is safe since the device_lock() already
protect the check/write from data race.

Fixes: 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device")
Signed-off-by: Lin Ma &lt;linma@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1b0e81416a24d6e9b8c2341e22e8bf48f8b8bfc9 ]

Commit 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device")
assumes the device_is_registered() in function nfc_dev_up() will help
to check when the rfkill is unregistered. However, this check only
take effect when device_del(&amp;dev-&gt;dev) is done in nfc_unregister_device().
Hence, the rfkill object is still possible be dereferenced.

The crash trace in latest kernel (5.18-rc2):

[   68.760105] ==================================================================
[   68.760330] BUG: KASAN: use-after-free in __lock_acquire+0x3ec1/0x6750
[   68.760756] Read of size 8 at addr ffff888009c93018 by task fuzz/313
[   68.760756]
[   68.760756] CPU: 0 PID: 313 Comm: fuzz Not tainted 5.18.0-rc2 #4
[   68.760756] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[   68.760756] Call Trace:
[   68.760756]  &lt;TASK&gt;
[   68.760756]  dump_stack_lvl+0x57/0x7d
[   68.760756]  print_report.cold+0x5e/0x5db
[   68.760756]  ? __lock_acquire+0x3ec1/0x6750
[   68.760756]  kasan_report+0xbe/0x1c0
[   68.760756]  ? __lock_acquire+0x3ec1/0x6750
[   68.760756]  __lock_acquire+0x3ec1/0x6750
[   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   68.760756]  ? register_lock_class+0x18d0/0x18d0
[   68.760756]  lock_acquire+0x1ac/0x4f0
[   68.760756]  ? rfkill_blocked+0xe/0x60
[   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   68.760756]  ? mutex_lock_io_nested+0x12c0/0x12c0
[   68.760756]  ? nla_get_range_signed+0x540/0x540
[   68.760756]  ? _raw_spin_lock_irqsave+0x4e/0x50
[   68.760756]  _raw_spin_lock_irqsave+0x39/0x50
[   68.760756]  ? rfkill_blocked+0xe/0x60
[   68.760756]  rfkill_blocked+0xe/0x60
[   68.760756]  nfc_dev_up+0x84/0x260
[   68.760756]  nfc_genl_dev_up+0x90/0xe0
[   68.760756]  genl_family_rcv_msg_doit+0x1f4/0x2f0
[   68.760756]  ? genl_family_rcv_msg_attrs_parse.constprop.0+0x230/0x230
[   68.760756]  ? security_capable+0x51/0x90
[   68.760756]  genl_rcv_msg+0x280/0x500
[   68.760756]  ? genl_get_cmd+0x3c0/0x3c0
[   68.760756]  ? lock_acquire+0x1ac/0x4f0
[   68.760756]  ? nfc_genl_dev_down+0xe0/0xe0
[   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   68.760756]  netlink_rcv_skb+0x11b/0x340
[   68.760756]  ? genl_get_cmd+0x3c0/0x3c0
[   68.760756]  ? netlink_ack+0x9c0/0x9c0
[   68.760756]  ? netlink_deliver_tap+0x136/0xb00
[   68.760756]  genl_rcv+0x1f/0x30
[   68.760756]  netlink_unicast+0x430/0x710
[   68.760756]  ? memset+0x20/0x40
[   68.760756]  ? netlink_attachskb+0x740/0x740
[   68.760756]  ? __build_skb_around+0x1f4/0x2a0
[   68.760756]  netlink_sendmsg+0x75d/0xc00
[   68.760756]  ? netlink_unicast+0x710/0x710
[   68.760756]  ? netlink_unicast+0x710/0x710
[   68.760756]  sock_sendmsg+0xdf/0x110
[   68.760756]  __sys_sendto+0x19e/0x270
[   68.760756]  ? __ia32_sys_getpeername+0xa0/0xa0
[   68.760756]  ? fd_install+0x178/0x4c0
[   68.760756]  ? fd_install+0x195/0x4c0
[   68.760756]  ? kernel_fpu_begin_mask+0x1c0/0x1c0
[   68.760756]  __x64_sys_sendto+0xd8/0x1b0
[   68.760756]  ? lockdep_hardirqs_on+0xbf/0x130
[   68.760756]  ? syscall_enter_from_user_mode+0x1d/0x50
[   68.760756]  do_syscall_64+0x3b/0x90
[   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   68.760756] RIP: 0033:0x7f67fb50e6b3
...
[   68.760756] RSP: 002b:00007f67fa91fe90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
[   68.760756] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f67fb50e6b3
[   68.760756] RDX: 000000000000001c RSI: 0000559354603090 RDI: 0000000000000003
[   68.760756] RBP: 00007f67fa91ff00 R08: 00007f67fa91fedc R09: 000000000000000c
[   68.760756] R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe824d496e
[   68.760756] R13: 00007ffe824d496f R14: 00007f67fa120000 R15: 0000000000000003

[   68.760756]  &lt;/TASK&gt;
[   68.760756]
[   68.760756] Allocated by task 279:
[   68.760756]  kasan_save_stack+0x1e/0x40
[   68.760756]  __kasan_kmalloc+0x81/0xa0
[   68.760756]  rfkill_alloc+0x7f/0x280
[   68.760756]  nfc_register_device+0xa3/0x1a0
[   68.760756]  nci_register_device+0x77a/0xad0
[   68.760756]  nfcmrvl_nci_register_dev+0x20b/0x2c0
[   68.760756]  nfcmrvl_nci_uart_open+0xf2/0x1dd
[   68.760756]  nci_uart_tty_ioctl+0x2c3/0x4a0
[   68.760756]  tty_ioctl+0x764/0x1310
[   68.760756]  __x64_sys_ioctl+0x122/0x190
[   68.760756]  do_syscall_64+0x3b/0x90
[   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   68.760756]
[   68.760756] Freed by task 314:
[   68.760756]  kasan_save_stack+0x1e/0x40
[   68.760756]  kasan_set_track+0x21/0x30
[   68.760756]  kasan_set_free_info+0x20/0x30
[   68.760756]  __kasan_slab_free+0x108/0x170
[   68.760756]  kfree+0xb0/0x330
[   68.760756]  device_release+0x96/0x200
[   68.760756]  kobject_put+0xf9/0x1d0
[   68.760756]  nfc_unregister_device+0x77/0x190
[   68.760756]  nfcmrvl_nci_unregister_dev+0x88/0xd0
[   68.760756]  nci_uart_tty_close+0xdf/0x180
[   68.760756]  tty_ldisc_kill+0x73/0x110
[   68.760756]  tty_ldisc_hangup+0x281/0x5b0
[   68.760756]  __tty_hangup.part.0+0x431/0x890
[   68.760756]  tty_release+0x3a8/0xc80
[   68.760756]  __fput+0x1f0/0x8c0
[   68.760756]  task_work_run+0xc9/0x170
[   68.760756]  exit_to_user_mode_prepare+0x194/0x1a0
[   68.760756]  syscall_exit_to_user_mode+0x19/0x50
[   68.760756]  do_syscall_64+0x48/0x90
[   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae

This patch just add the null out of dev-&gt;rfkill to make sure such
dereference cannot happen. This is safe since the device_lock() already
protect the check/write from data race.

Fixes: 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device")
Signed-off-by: Lin Ma &lt;linma@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>NFC: nci: fix sleep in atomic context bugs caused by nci_skb_alloc</title>
<updated>2022-05-25T07:59:08+00:00</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-05-17T01:25:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=11818186914493a1530c6217ba2de2d4212b2738'/>
<id>11818186914493a1530c6217ba2de2d4212b2738</id>
<content type='text'>
[ Upstream commit 23dd4581350d4ffa23d58976ec46408f8f4c1e16 ]

There are sleep in atomic context bugs when the request to secure
element of st-nci is timeout. The root cause is that nci_skb_alloc
with GFP_KERNEL parameter is called in st_nci_se_wt_timeout which is
a timer handler. The call paths that could trigger bugs are shown below:

    (interrupt context 1)
st_nci_se_wt_timeout
  nci_hci_send_event
    nci_hci_send_data
      nci_skb_alloc(..., GFP_KERNEL) //may sleep

   (interrupt context 2)
st_nci_se_wt_timeout
  nci_hci_send_event
    nci_hci_send_data
      nci_send_data
        nci_queue_tx_data_frags
          nci_skb_alloc(..., GFP_KERNEL) //may sleep

This patch changes allocation mode of nci_skb_alloc from GFP_KERNEL to
GFP_ATOMIC in order to prevent atomic context sleeping. The GFP_ATOMIC
flag makes memory allocation operation could be used in atomic context.

Fixes: ed06aeefdac3 ("nfc: st-nci: Rename st21nfcb to st-nci")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Link: https://lore.kernel.org/r/20220517012530.75714-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 23dd4581350d4ffa23d58976ec46408f8f4c1e16 ]

There are sleep in atomic context bugs when the request to secure
element of st-nci is timeout. The root cause is that nci_skb_alloc
with GFP_KERNEL parameter is called in st_nci_se_wt_timeout which is
a timer handler. The call paths that could trigger bugs are shown below:

    (interrupt context 1)
st_nci_se_wt_timeout
  nci_hci_send_event
    nci_hci_send_data
      nci_skb_alloc(..., GFP_KERNEL) //may sleep

   (interrupt context 2)
st_nci_se_wt_timeout
  nci_hci_send_event
    nci_hci_send_data
      nci_send_data
        nci_queue_tx_data_frags
          nci_skb_alloc(..., GFP_KERNEL) //may sleep

This patch changes allocation mode of nci_skb_alloc from GFP_KERNEL to
GFP_ATOMIC in order to prevent atomic context sleeping. The GFP_ATOMIC
flag makes memory allocation operation could be used in atomic context.

Fixes: ed06aeefdac3 ("nfc: st-nci: Rename st21nfcb to st-nci")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Link: https://lore.kernel.org/r/20220517012530.75714-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>NFC: netlink: fix sleep in atomic bug when firmware download timeout</title>
<updated>2022-05-12T10:32:26+00:00</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-05-04T05:58:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=63a545103b77091f2309b44a8975cdf255bb99b2'/>
<id>63a545103b77091f2309b44a8975cdf255bb99b2</id>
<content type='text'>
commit 4071bf121d59944d5cd2238de0642f3d7995a997 upstream.

There are sleep in atomic bug that could cause kernel panic during
firmware download process. The root cause is that nlmsg_new with
GFP_KERNEL parameter is called in fw_dnld_timeout which is a timer
handler. The call trace is shown below:

BUG: sleeping function called from invalid context at include/linux/sched/mm.h:265
Call Trace:
kmem_cache_alloc_node
__alloc_skb
nfc_genl_fw_download_done
call_timer_fn
__run_timers.part.0
run_timer_softirq
__do_softirq
...

The nlmsg_new with GFP_KERNEL parameter may sleep during memory
allocation process, and the timer handler is run as the result of
a "software interrupt" that should not call any other function
that could sleep.

This patch changes allocation mode of netlink message from GFP_KERNEL
to GFP_ATOMIC in order to prevent sleep in atomic bug. The GFP_ATOMIC
flag makes memory allocation operation could be used in atomic context.

Fixes: 9674da8759df ("NFC: Add firmware upload netlink command")
Fixes: 9ea7187c53f6 ("NFC: netlink: Rename CMD_FW_UPLOAD to CMD_FW_DOWNLOAD")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Link: https://lore.kernel.org/r/20220504055847.38026-1-duoming@zju.edu.cn
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4071bf121d59944d5cd2238de0642f3d7995a997 upstream.

There are sleep in atomic bug that could cause kernel panic during
firmware download process. The root cause is that nlmsg_new with
GFP_KERNEL parameter is called in fw_dnld_timeout which is a timer
handler. The call trace is shown below:

BUG: sleeping function called from invalid context at include/linux/sched/mm.h:265
Call Trace:
kmem_cache_alloc_node
__alloc_skb
nfc_genl_fw_download_done
call_timer_fn
__run_timers.part.0
run_timer_softirq
__do_softirq
...

The nlmsg_new with GFP_KERNEL parameter may sleep during memory
allocation process, and the timer handler is run as the result of
a "software interrupt" that should not call any other function
that could sleep.

This patch changes allocation mode of netlink message from GFP_KERNEL
to GFP_ATOMIC in order to prevent sleep in atomic bug. The GFP_ATOMIC
flag makes memory allocation operation could be used in atomic context.

Fixes: 9674da8759df ("NFC: Add firmware upload netlink command")
Fixes: 9ea7187c53f6 ("NFC: netlink: Rename CMD_FW_UPLOAD to CMD_FW_DOWNLOAD")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Link: https://lore.kernel.org/r/20220504055847.38026-1-duoming@zju.edu.cn
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nfc: replace improper check device_is_registered() in netlink related functions</title>
<updated>2022-05-12T10:32:26+00:00</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-04-29T12:45:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b58d6e565d83443c51b3fc076bd4472674aca0c'/>
<id>8b58d6e565d83443c51b3fc076bd4472674aca0c</id>
<content type='text'>
commit da5c0f119203ad9728920456a0f52a6d850c01cd upstream.

The device_is_registered() in nfc core is used to check whether
nfc device is registered in netlink related functions such as
nfc_fw_download(), nfc_dev_up() and so on. Although device_is_registered()
is protected by device_lock, there is still a race condition between
device_del() and device_is_registered(). The root cause is that
kobject_del() in device_del() is not protected by device_lock.

   (cleanup task)         |     (netlink task)
                          |
nfc_unregister_device     | nfc_fw_download
 device_del               |  device_lock
  ...                     |   if (!device_is_registered)//(1)
  kobject_del//(2)        |   ...
 ...                      |  device_unlock

The device_is_registered() returns the value of state_in_sysfs and
the state_in_sysfs is set to zero in kobject_del(). If we pass check in
position (1), then set zero in position (2). As a result, the check
in position (1) is useless.

This patch uses bool variable instead of device_is_registered() to judge
whether the nfc device is registered, which is well synchronized.

Fixes: 3e256b8f8dfa ("NFC: add nfc subsystem core")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit da5c0f119203ad9728920456a0f52a6d850c01cd upstream.

The device_is_registered() in nfc core is used to check whether
nfc device is registered in netlink related functions such as
nfc_fw_download(), nfc_dev_up() and so on. Although device_is_registered()
is protected by device_lock, there is still a race condition between
device_del() and device_is_registered(). The root cause is that
kobject_del() in device_del() is not protected by device_lock.

   (cleanup task)         |     (netlink task)
                          |
nfc_unregister_device     | nfc_fw_download
 device_del               |  device_lock
  ...                     |   if (!device_is_registered)//(1)
  kobject_del//(2)        |   ...
 ...                      |  device_unlock

The device_is_registered() returns the value of state_in_sysfs and
the state_in_sysfs is set to zero in kobject_del(). If we pass check in
position (1), then set zero in position (2). As a result, the check
in position (1) is useless.

This patch uses bool variable instead of device_is_registered() to judge
whether the nfc device is registered, which is well synchronized.

Fixes: 3e256b8f8dfa ("NFC: add nfc subsystem core")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nfc: nci: add flush_workqueue to prevent uaf</title>
<updated>2022-04-20T07:36:17+00:00</updated>
<author>
<name>Lin Ma</name>
<email>linma@zju.edu.cn</email>
</author>
<published>2022-04-12T16:04:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=edd4600120641e1714e30112e69a548cfb68e067'/>
<id>edd4600120641e1714e30112e69a548cfb68e067</id>
<content type='text'>
[ Upstream commit ef27324e2cb7bb24542d6cb2571740eefe6b00dc ]

Our detector found a concurrent use-after-free bug when detaching an
NCI device. The main reason for this bug is the unexpected scheduling
between the used delayed mechanism (timer and workqueue).

The race can be demonstrated below:

Thread-1                           Thread-2
                                 | nci_dev_up()
                                 |   nci_open_device()
                                 |     __nci_request(nci_reset_req)
                                 |       nci_send_cmd
                                 |         queue_work(cmd_work)
nci_unregister_device()          |
  nci_close_device()             | ...
    del_timer_sync(cmd_timer)[1] |
...                              | Worker
nci_free_device()                | nci_cmd_work()
  kfree(ndev)[3]                 |   mod_timer(cmd_timer)[2]

In short, the cleanup routine thought that the cmd_timer has already
been detached by [1] but the mod_timer can re-attach the timer [2], even
it is already released [3], resulting in UAF.

This UAF is easy to trigger, crash trace by POC is like below

[   66.703713] ==================================================================
[   66.703974] BUG: KASAN: use-after-free in enqueue_timer+0x448/0x490
[   66.703974] Write of size 8 at addr ffff888009fb7058 by task kworker/u4:1/33
[   66.703974]
[   66.703974] CPU: 1 PID: 33 Comm: kworker/u4:1 Not tainted 5.18.0-rc2 #5
[   66.703974] Workqueue: nfc2_nci_cmd_wq nci_cmd_work
[   66.703974] Call Trace:
[   66.703974]  &lt;TASK&gt;
[   66.703974]  dump_stack_lvl+0x57/0x7d
[   66.703974]  print_report.cold+0x5e/0x5db
[   66.703974]  ? enqueue_timer+0x448/0x490
[   66.703974]  kasan_report+0xbe/0x1c0
[   66.703974]  ? enqueue_timer+0x448/0x490
[   66.703974]  enqueue_timer+0x448/0x490
[   66.703974]  __mod_timer+0x5e6/0xb80
[   66.703974]  ? mark_held_locks+0x9e/0xe0
[   66.703974]  ? try_to_del_timer_sync+0xf0/0xf0
[   66.703974]  ? lockdep_hardirqs_on_prepare+0x17b/0x410
[   66.703974]  ? queue_work_on+0x61/0x80
[   66.703974]  ? lockdep_hardirqs_on+0xbf/0x130
[   66.703974]  process_one_work+0x8bb/0x1510
[   66.703974]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   66.703974]  ? pwq_dec_nr_in_flight+0x230/0x230
[   66.703974]  ? rwlock_bug.part.0+0x90/0x90
[   66.703974]  ? _raw_spin_lock_irq+0x41/0x50
[   66.703974]  worker_thread+0x575/0x1190
[   66.703974]  ? process_one_work+0x1510/0x1510
[   66.703974]  kthread+0x2a0/0x340
[   66.703974]  ? kthread_complete_and_exit+0x20/0x20
[   66.703974]  ret_from_fork+0x22/0x30
[   66.703974]  &lt;/TASK&gt;
[   66.703974]
[   66.703974] Allocated by task 267:
[   66.703974]  kasan_save_stack+0x1e/0x40
[   66.703974]  __kasan_kmalloc+0x81/0xa0
[   66.703974]  nci_allocate_device+0xd3/0x390
[   66.703974]  nfcmrvl_nci_register_dev+0x183/0x2c0
[   66.703974]  nfcmrvl_nci_uart_open+0xf2/0x1dd
[   66.703974]  nci_uart_tty_ioctl+0x2c3/0x4a0
[   66.703974]  tty_ioctl+0x764/0x1310
[   66.703974]  __x64_sys_ioctl+0x122/0x190
[   66.703974]  do_syscall_64+0x3b/0x90
[   66.703974]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   66.703974]
[   66.703974] Freed by task 406:
[   66.703974]  kasan_save_stack+0x1e/0x40
[   66.703974]  kasan_set_track+0x21/0x30
[   66.703974]  kasan_set_free_info+0x20/0x30
[   66.703974]  __kasan_slab_free+0x108/0x170
[   66.703974]  kfree+0xb0/0x330
[   66.703974]  nfcmrvl_nci_unregister_dev+0x90/0xd0
[   66.703974]  nci_uart_tty_close+0xdf/0x180
[   66.703974]  tty_ldisc_kill+0x73/0x110
[   66.703974]  tty_ldisc_hangup+0x281/0x5b0
[   66.703974]  __tty_hangup.part.0+0x431/0x890
[   66.703974]  tty_release+0x3a8/0xc80
[   66.703974]  __fput+0x1f0/0x8c0
[   66.703974]  task_work_run+0xc9/0x170
[   66.703974]  exit_to_user_mode_prepare+0x194/0x1a0
[   66.703974]  syscall_exit_to_user_mode+0x19/0x50
[   66.703974]  do_syscall_64+0x48/0x90
[   66.703974]  entry_SYSCALL_64_after_hwframe+0x44/0xae

To fix the UAF, this patch adds flush_workqueue() to ensure the
nci_cmd_work is finished before the following del_timer_sync.
This combination will promise the timer is actually detached.

Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation")
Signed-off-by: Lin Ma &lt;linma@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ef27324e2cb7bb24542d6cb2571740eefe6b00dc ]

Our detector found a concurrent use-after-free bug when detaching an
NCI device. The main reason for this bug is the unexpected scheduling
between the used delayed mechanism (timer and workqueue).

The race can be demonstrated below:

Thread-1                           Thread-2
                                 | nci_dev_up()
                                 |   nci_open_device()
                                 |     __nci_request(nci_reset_req)
                                 |       nci_send_cmd
                                 |         queue_work(cmd_work)
nci_unregister_device()          |
  nci_close_device()             | ...
    del_timer_sync(cmd_timer)[1] |
...                              | Worker
nci_free_device()                | nci_cmd_work()
  kfree(ndev)[3]                 |   mod_timer(cmd_timer)[2]

In short, the cleanup routine thought that the cmd_timer has already
been detached by [1] but the mod_timer can re-attach the timer [2], even
it is already released [3], resulting in UAF.

This UAF is easy to trigger, crash trace by POC is like below

[   66.703713] ==================================================================
[   66.703974] BUG: KASAN: use-after-free in enqueue_timer+0x448/0x490
[   66.703974] Write of size 8 at addr ffff888009fb7058 by task kworker/u4:1/33
[   66.703974]
[   66.703974] CPU: 1 PID: 33 Comm: kworker/u4:1 Not tainted 5.18.0-rc2 #5
[   66.703974] Workqueue: nfc2_nci_cmd_wq nci_cmd_work
[   66.703974] Call Trace:
[   66.703974]  &lt;TASK&gt;
[   66.703974]  dump_stack_lvl+0x57/0x7d
[   66.703974]  print_report.cold+0x5e/0x5db
[   66.703974]  ? enqueue_timer+0x448/0x490
[   66.703974]  kasan_report+0xbe/0x1c0
[   66.703974]  ? enqueue_timer+0x448/0x490
[   66.703974]  enqueue_timer+0x448/0x490
[   66.703974]  __mod_timer+0x5e6/0xb80
[   66.703974]  ? mark_held_locks+0x9e/0xe0
[   66.703974]  ? try_to_del_timer_sync+0xf0/0xf0
[   66.703974]  ? lockdep_hardirqs_on_prepare+0x17b/0x410
[   66.703974]  ? queue_work_on+0x61/0x80
[   66.703974]  ? lockdep_hardirqs_on+0xbf/0x130
[   66.703974]  process_one_work+0x8bb/0x1510
[   66.703974]  ? lockdep_hardirqs_on_prepare+0x410/0x410
[   66.703974]  ? pwq_dec_nr_in_flight+0x230/0x230
[   66.703974]  ? rwlock_bug.part.0+0x90/0x90
[   66.703974]  ? _raw_spin_lock_irq+0x41/0x50
[   66.703974]  worker_thread+0x575/0x1190
[   66.703974]  ? process_one_work+0x1510/0x1510
[   66.703974]  kthread+0x2a0/0x340
[   66.703974]  ? kthread_complete_and_exit+0x20/0x20
[   66.703974]  ret_from_fork+0x22/0x30
[   66.703974]  &lt;/TASK&gt;
[   66.703974]
[   66.703974] Allocated by task 267:
[   66.703974]  kasan_save_stack+0x1e/0x40
[   66.703974]  __kasan_kmalloc+0x81/0xa0
[   66.703974]  nci_allocate_device+0xd3/0x390
[   66.703974]  nfcmrvl_nci_register_dev+0x183/0x2c0
[   66.703974]  nfcmrvl_nci_uart_open+0xf2/0x1dd
[   66.703974]  nci_uart_tty_ioctl+0x2c3/0x4a0
[   66.703974]  tty_ioctl+0x764/0x1310
[   66.703974]  __x64_sys_ioctl+0x122/0x190
[   66.703974]  do_syscall_64+0x3b/0x90
[   66.703974]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   66.703974]
[   66.703974] Freed by task 406:
[   66.703974]  kasan_save_stack+0x1e/0x40
[   66.703974]  kasan_set_track+0x21/0x30
[   66.703974]  kasan_set_free_info+0x20/0x30
[   66.703974]  __kasan_slab_free+0x108/0x170
[   66.703974]  kfree+0xb0/0x330
[   66.703974]  nfcmrvl_nci_unregister_dev+0x90/0xd0
[   66.703974]  nci_uart_tty_close+0xdf/0x180
[   66.703974]  tty_ldisc_kill+0x73/0x110
[   66.703974]  tty_ldisc_hangup+0x281/0x5b0
[   66.703974]  __tty_hangup.part.0+0x431/0x890
[   66.703974]  tty_release+0x3a8/0xc80
[   66.703974]  __fput+0x1f0/0x8c0
[   66.703974]  task_work_run+0xc9/0x170
[   66.703974]  exit_to_user_mode_prepare+0x194/0x1a0
[   66.703974]  syscall_exit_to_user_mode+0x19/0x50
[   66.703974]  do_syscall_64+0x48/0x90
[   66.703974]  entry_SYSCALL_64_after_hwframe+0x44/0xae

To fix the UAF, this patch adds flush_workqueue() to ensure the
nci_cmd_work is finished before the following del_timer_sync.
This combination will promise the timer is actually detached.

Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation")
Signed-off-by: Lin Ma &lt;linma@zju.edu.cn&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@linaro.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'net-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2022-01-20T08:57:05+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-20T08:57:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa2e1ba3e9e39072fa7a6a9d11ac432c505b4ac7'/>
<id>fa2e1ba3e9e39072fa7a6a9d11ac432c505b4ac7</id>
<content type='text'>
Pull networking fixes from Jakub Kicinski:
 "Including fixes from netfilter, bpf.

  Quite a handful of old regression fixes but most of those are
  pre-5.16.

  Current release - regressions:

   - fix memory leaks in the skb free deferral scheme if upper layer
     protocols are used, i.e. in-kernel TCP readers like TLS

  Current release - new code bugs:

   - nf_tables: fix NULL check typo in _clone() functions

   - change the default to y for Vertexcom vendor Kconfig

   - a couple of fixes to incorrect uses of ref tracking

   - two fixes for constifying netdev-&gt;dev_addr

  Previous releases - regressions:

   - bpf:
      - various verifier fixes mainly around register offset handling
        when passed to helper functions
      - fix mount source displayed for bpffs (none -&gt; bpffs)

   - bonding:
      - fix extraction of ports for connection hash calculation
      - fix bond_xmit_broadcast return value when some devices are down

   - phy: marvell: add Marvell specific PHY loopback

   - sch_api: don't skip qdisc attach on ingress, prevent ref leak

   - htb: restore minimal packet size handling in rate control

   - sfp: fix high power modules without diagnostic monitoring

   - mscc: ocelot:
      - don't let phylink re-enable TX PAUSE on the NPI port
      - don't dereference NULL pointers with shared tc filters

   - smsc95xx: correct reset handling for LAN9514

   - cpsw: avoid alignment faults by taking NET_IP_ALIGN into account

   - phy: micrel: use kszphy_suspend/_resume for irq aware devices,
     avoid races with the interrupt

  Previous releases - always broken:

   - xdp: check prog type before updating BPF link

   - smc: resolve various races around abnormal connection termination

   - sit: allow encapsulated IPv6 traffic to be delivered locally

   - axienet: fix init/reset handling, add missing barriers, read the
     right status words, stop queues correctly

   - add missing dev_put() in sock_timestamping_bind_phc()

  Misc:

   - ipv4: prevent accidentally passing RTO_ONLINK to
     ip_route_output_key_hash() by sanitizing flags

   - ipv4: avoid quadratic behavior in netns dismantle

   - stmmac: dwmac-oxnas: add support for OX810SE

   - fsl: xgmac_mdio: add workaround for erratum A-009885"

* tag 'net-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (92 commits)
  ipv4: add net_hash_mix() dispersion to fib_info_laddrhash keys
  ipv4: avoid quadratic behavior in netns dismantle
  net/fsl: xgmac_mdio: Fix incorrect iounmap when removing module
  powerpc/fsl/dts: Enable WA for erratum A-009885 on fman3l MDIO buses
  dt-bindings: net: Document fsl,erratum-a009885
  net/fsl: xgmac_mdio: Add workaround for erratum A-009885
  net: mscc: ocelot: fix using match before it is set
  net: phy: micrel: use kszphy_suspend()/kszphy_resume for irq aware devices
  net: cpsw: avoid alignment faults by taking NET_IP_ALIGN into account
  nfc: llcp: fix NULL error pointer dereference on sendmsg() after failed bind()
  net: axienet: increase default TX ring size to 128
  net: axienet: fix for TX busy handling
  net: axienet: fix number of TX ring slots for available check
  net: axienet: Fix TX ring slot available check
  net: axienet: limit minimum TX ring size
  net: axienet: add missing memory barriers
  net: axienet: reset core on initialization prior to MDIO access
  net: axienet: Wait for PhyRstCmplt after core reset
  net: axienet: increase reset timeout
  bpf, selftests: Add ringbuf memory type confusion test
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from Jakub Kicinski:
 "Including fixes from netfilter, bpf.

  Quite a handful of old regression fixes but most of those are
  pre-5.16.

  Current release - regressions:

   - fix memory leaks in the skb free deferral scheme if upper layer
     protocols are used, i.e. in-kernel TCP readers like TLS

  Current release - new code bugs:

   - nf_tables: fix NULL check typo in _clone() functions

   - change the default to y for Vertexcom vendor Kconfig

   - a couple of fixes to incorrect uses of ref tracking

   - two fixes for constifying netdev-&gt;dev_addr

  Previous releases - regressions:

   - bpf:
      - various verifier fixes mainly around register offset handling
        when passed to helper functions
      - fix mount source displayed for bpffs (none -&gt; bpffs)

   - bonding:
      - fix extraction of ports for connection hash calculation
      - fix bond_xmit_broadcast return value when some devices are down

   - phy: marvell: add Marvell specific PHY loopback

   - sch_api: don't skip qdisc attach on ingress, prevent ref leak

   - htb: restore minimal packet size handling in rate control

   - sfp: fix high power modules without diagnostic monitoring

   - mscc: ocelot:
      - don't let phylink re-enable TX PAUSE on the NPI port
      - don't dereference NULL pointers with shared tc filters

   - smsc95xx: correct reset handling for LAN9514

   - cpsw: avoid alignment faults by taking NET_IP_ALIGN into account

   - phy: micrel: use kszphy_suspend/_resume for irq aware devices,
     avoid races with the interrupt

  Previous releases - always broken:

   - xdp: check prog type before updating BPF link

   - smc: resolve various races around abnormal connection termination

   - sit: allow encapsulated IPv6 traffic to be delivered locally

   - axienet: fix init/reset handling, add missing barriers, read the
     right status words, stop queues correctly

   - add missing dev_put() in sock_timestamping_bind_phc()

  Misc:

   - ipv4: prevent accidentally passing RTO_ONLINK to
     ip_route_output_key_hash() by sanitizing flags

   - ipv4: avoid quadratic behavior in netns dismantle

   - stmmac: dwmac-oxnas: add support for OX810SE

   - fsl: xgmac_mdio: add workaround for erratum A-009885"

* tag 'net-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (92 commits)
  ipv4: add net_hash_mix() dispersion to fib_info_laddrhash keys
  ipv4: avoid quadratic behavior in netns dismantle
  net/fsl: xgmac_mdio: Fix incorrect iounmap when removing module
  powerpc/fsl/dts: Enable WA for erratum A-009885 on fman3l MDIO buses
  dt-bindings: net: Document fsl,erratum-a009885
  net/fsl: xgmac_mdio: Add workaround for erratum A-009885
  net: mscc: ocelot: fix using match before it is set
  net: phy: micrel: use kszphy_suspend()/kszphy_resume for irq aware devices
  net: cpsw: avoid alignment faults by taking NET_IP_ALIGN into account
  nfc: llcp: fix NULL error pointer dereference on sendmsg() after failed bind()
  net: axienet: increase default TX ring size to 128
  net: axienet: fix for TX busy handling
  net: axienet: fix number of TX ring slots for available check
  net: axienet: Fix TX ring slot available check
  net: axienet: limit minimum TX ring size
  net: axienet: add missing memory barriers
  net: axienet: reset core on initialization prior to MDIO access
  net: axienet: Wait for PhyRstCmplt after core reset
  net: axienet: increase reset timeout
  bpf, selftests: Add ringbuf memory type confusion test
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>nfc: llcp: fix NULL error pointer dereference on sendmsg() after failed bind()</title>
<updated>2022-01-19T14:11:30+00:00</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>krzysztof.kozlowski@canonical.com</email>
</author>
<published>2022-01-19T07:48:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dded08927ca3c31a5c37f8e7f95fe98770475dd4'/>
<id>dded08927ca3c31a5c37f8e7f95fe98770475dd4</id>
<content type='text'>
Syzbot detected a NULL pointer dereference of nfc_llcp_sock-&gt;dev pointer
(which is a 'struct nfc_dev *') with calls to llcp_sock_sendmsg() after
a failed llcp_sock_bind(). The message being sent is a SOCK_DGRAM.

KASAN report:

  BUG: KASAN: null-ptr-deref in nfc_alloc_send_skb+0x2d/0xc0
  Read of size 4 at addr 00000000000005c8 by task llcp_sock_nfc_a/899

  CPU: 5 PID: 899 Comm: llcp_sock_nfc_a Not tainted 5.16.0-rc6-next-20211224-00001-gc6437fbf18b0 #125
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
  Call Trace:
   &lt;TASK&gt;
   dump_stack_lvl+0x45/0x59
   ? nfc_alloc_send_skb+0x2d/0xc0
   __kasan_report.cold+0x117/0x11c
   ? mark_lock+0x480/0x4f0
   ? nfc_alloc_send_skb+0x2d/0xc0
   kasan_report+0x38/0x50
   nfc_alloc_send_skb+0x2d/0xc0
   nfc_llcp_send_ui_frame+0x18c/0x2a0
   ? nfc_llcp_send_i_frame+0x230/0x230
   ? __local_bh_enable_ip+0x86/0xe0
   ? llcp_sock_connect+0x470/0x470
   ? llcp_sock_connect+0x470/0x470
   sock_sendmsg+0x8e/0xa0
   ____sys_sendmsg+0x253/0x3f0
   ...

The issue was visible only with multiple simultaneous calls to bind() and
sendmsg(), which resulted in most of the bind() calls to fail.  The
bind() was failing on checking if there is available WKS/SDP/SAP
(respective bit in 'struct nfc_llcp_local' fields).  When there was no
available WKS/SDP/SAP, the bind returned error but the sendmsg() to such
socket was able to trigger mentioned NULL pointer dereference of
nfc_llcp_sock-&gt;dev.

The code looks simply racy and currently it protects several paths
against race with checks for (!nfc_llcp_sock-&gt;local) which is NULL-ified
in error paths of bind().  The llcp_sock_sendmsg() did not have such
check but called function nfc_llcp_send_ui_frame() had, although not
protected with lock_sock().

Therefore the race could look like (same socket is used all the time):
  CPU0                                     CPU1
  ====                                     ====
  llcp_sock_bind()
  - lock_sock()
    - success
  - release_sock()
  - return 0
                                           llcp_sock_sendmsg()
                                           - lock_sock()
                                           - release_sock()
  llcp_sock_bind(), same socket
  - lock_sock()
    - error
                                           - nfc_llcp_send_ui_frame()
                                             - if (!llcp_sock-&gt;local)
    - llcp_sock-&gt;local = NULL
    - nfc_put_device(dev)
                                             - dereference llcp_sock-&gt;dev
  - release_sock()
  - return -ERRNO

The nfc_llcp_send_ui_frame() checked llcp_sock-&gt;local outside of the
lock, which is racy and ineffective check.  Instead, its caller
llcp_sock_sendmsg(), should perform the check inside lock_sock().

Reported-and-tested-by: syzbot+7f23bcddf626e0593a39@syzkaller.appspotmail.com
Fixes: b874dec21d1c ("NFC: Implement LLCP connection less Tx path")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Syzbot detected a NULL pointer dereference of nfc_llcp_sock-&gt;dev pointer
(which is a 'struct nfc_dev *') with calls to llcp_sock_sendmsg() after
a failed llcp_sock_bind(). The message being sent is a SOCK_DGRAM.

KASAN report:

  BUG: KASAN: null-ptr-deref in nfc_alloc_send_skb+0x2d/0xc0
  Read of size 4 at addr 00000000000005c8 by task llcp_sock_nfc_a/899

  CPU: 5 PID: 899 Comm: llcp_sock_nfc_a Not tainted 5.16.0-rc6-next-20211224-00001-gc6437fbf18b0 #125
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
  Call Trace:
   &lt;TASK&gt;
   dump_stack_lvl+0x45/0x59
   ? nfc_alloc_send_skb+0x2d/0xc0
   __kasan_report.cold+0x117/0x11c
   ? mark_lock+0x480/0x4f0
   ? nfc_alloc_send_skb+0x2d/0xc0
   kasan_report+0x38/0x50
   nfc_alloc_send_skb+0x2d/0xc0
   nfc_llcp_send_ui_frame+0x18c/0x2a0
   ? nfc_llcp_send_i_frame+0x230/0x230
   ? __local_bh_enable_ip+0x86/0xe0
   ? llcp_sock_connect+0x470/0x470
   ? llcp_sock_connect+0x470/0x470
   sock_sendmsg+0x8e/0xa0
   ____sys_sendmsg+0x253/0x3f0
   ...

The issue was visible only with multiple simultaneous calls to bind() and
sendmsg(), which resulted in most of the bind() calls to fail.  The
bind() was failing on checking if there is available WKS/SDP/SAP
(respective bit in 'struct nfc_llcp_local' fields).  When there was no
available WKS/SDP/SAP, the bind returned error but the sendmsg() to such
socket was able to trigger mentioned NULL pointer dereference of
nfc_llcp_sock-&gt;dev.

The code looks simply racy and currently it protects several paths
against race with checks for (!nfc_llcp_sock-&gt;local) which is NULL-ified
in error paths of bind().  The llcp_sock_sendmsg() did not have such
check but called function nfc_llcp_send_ui_frame() had, although not
protected with lock_sock().

Therefore the race could look like (same socket is used all the time):
  CPU0                                     CPU1
  ====                                     ====
  llcp_sock_bind()
  - lock_sock()
    - success
  - release_sock()
  - return 0
                                           llcp_sock_sendmsg()
                                           - lock_sock()
                                           - release_sock()
  llcp_sock_bind(), same socket
  - lock_sock()
    - error
                                           - nfc_llcp_send_ui_frame()
                                             - if (!llcp_sock-&gt;local)
    - llcp_sock-&gt;local = NULL
    - nfc_put_device(dev)
                                             - dereference llcp_sock-&gt;dev
  - release_sock()
  - return -ERRNO

The nfc_llcp_send_ui_frame() checked llcp_sock-&gt;local outside of the
lock, which is racy and ineffective check.  Instead, its caller
llcp_sock_sendmsg(), should perform the check inside lock_sock().

Reported-and-tested-by: syzbot+7f23bcddf626e0593a39@syzkaller.appspotmail.com
Fixes: b874dec21d1c ("NFC: Implement LLCP connection less Tx path")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge 5.16-rc6 into tty-next</title>
<updated>2021-12-20T09:00:30+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2021-12-20T09:00:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=35eaa42c4a1017c08d0572008db375becb621744'/>
<id>35eaa42c4a1017c08d0572008db375becb621744</id>
<content type='text'>
We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done</title>
<updated>2021-12-09T15:50:32+00:00</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>krzysztof.kozlowski@canonical.com</email>
</author>
<published>2021-12-09T08:13:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4cd8371a234d051f9c9557fcbb1f8c523b1c0d10'/>
<id>4cd8371a234d051f9c9557fcbb1f8c523b1c0d10</id>
<content type='text'>
The done() netlink callback nfc_genl_dump_ses_done() should check if
received argument is non-NULL, because its allocation could fail earlier
in dumpit() (nfc_genl_dump_ses()).

Fixes: ac22ac466a65 ("NFC: Add a GET_SE netlink API")
Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Link: https://lore.kernel.org/r/20211209081307.57337-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The done() netlink callback nfc_genl_dump_ses_done() should check if
received argument is non-NULL, because its allocation could fail earlier
in dumpit() (nfc_genl_dump_ses()).

Fixes: ac22ac466a65 ("NFC: Add a GET_SE netlink API")
Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Link: https://lore.kernel.org/r/20211209081307.57337-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nfc: fix segfault in nfc_genl_dump_devices_done</title>
<updated>2021-12-09T15:50:23+00:00</updated>
<author>
<name>Tadeusz Struk</name>
<email>tadeusz.struk@linaro.org</email>
</author>
<published>2021-12-08T18:27:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fd79a0cbf0b2e34bcc45b13acf962e2032a82203'/>
<id>fd79a0cbf0b2e34bcc45b13acf962e2032a82203</id>
<content type='text'>
When kmalloc in nfc_genl_dump_devices() fails then
nfc_genl_dump_devices_done() segfaults as below

KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 25 Comm: kworker/0:1 Not tainted 5.16.0-rc4-01180-g2a987e65025e-dirty #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-6.fc35 04/01/2014
Workqueue: events netlink_sock_destruct_work
RIP: 0010:klist_iter_exit+0x26/0x80
Call Trace:
&lt;TASK&gt;
class_dev_iter_exit+0x15/0x20
nfc_genl_dump_devices_done+0x3b/0x50
genl_lock_done+0x84/0xd0
netlink_sock_destruct+0x8f/0x270
__sk_destruct+0x64/0x3b0
sk_destruct+0xa8/0xd0
__sk_free+0x2e8/0x3d0
sk_free+0x51/0x90
netlink_sock_destruct_work+0x1c/0x20
process_one_work+0x411/0x710
worker_thread+0x6fd/0xa80

Link: https://syzkaller.appspot.com/bug?id=fc0fa5a53db9edd261d56e74325419faf18bd0df
Reported-by: syzbot+f9f76f4a0766420b4a02@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk &lt;tadeusz.struk@linaro.org&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Link: https://lore.kernel.org/r/20211208182742.340542-1-tadeusz.struk@linaro.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When kmalloc in nfc_genl_dump_devices() fails then
nfc_genl_dump_devices_done() segfaults as below

KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 25 Comm: kworker/0:1 Not tainted 5.16.0-rc4-01180-g2a987e65025e-dirty #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-6.fc35 04/01/2014
Workqueue: events netlink_sock_destruct_work
RIP: 0010:klist_iter_exit+0x26/0x80
Call Trace:
&lt;TASK&gt;
class_dev_iter_exit+0x15/0x20
nfc_genl_dump_devices_done+0x3b/0x50
genl_lock_done+0x84/0xd0
netlink_sock_destruct+0x8f/0x270
__sk_destruct+0x64/0x3b0
sk_destruct+0xa8/0xd0
__sk_free+0x2e8/0x3d0
sk_free+0x51/0x90
netlink_sock_destruct_work+0x1c/0x20
process_one_work+0x411/0x710
worker_thread+0x6fd/0xa80

Link: https://syzkaller.appspot.com/bug?id=fc0fa5a53db9edd261d56e74325419faf18bd0df
Reported-by: syzbot+f9f76f4a0766420b4a02@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk &lt;tadeusz.struk@linaro.org&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Link: https://lore.kernel.org/r/20211208182742.340542-1-tadeusz.struk@linaro.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
