<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/net/nfc/core.c, branch linus/master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/net/nfc/core.c?h=linus%2Fmaster</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/net/nfc/core.c?h=linus%2Fmaster'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-05-28T14:28:47Z</updated>
<entry>
<title>net: nfc: Directly use ida_alloc()/free()</title>
<updated>2022-05-28T14:28:47Z</updated>
<author>
<name>keliu</name>
<email>liuke94@huawei.com</email>
</author>
<published>2022-05-27T06:42:25Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=911799172d2f703cc14e9000c55d124d5e0a91a2'/>
<id>urn:sha1:911799172d2f703cc14e9000c55d124d5e0a91a2</id>
<content type='text'>
Use ida_alloc()/ida_free() instead of deprecated
ida_simple_get()/ida_simple_remove() .

Signed-off-by: keliu &lt;liuke94@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2022-05-05T20:03:18Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2022-05-05T20:03:18Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=c8227d568ddf2f38a8806fdcd2e20b9e11747d9a'/>
<id>urn:sha1:c8227d568ddf2f38a8806fdcd2e20b9e11747d9a</id>
<content type='text'>
tools/testing/selftests/net/forwarding/Makefile
  f62c5acc800e ("selftests/net/forwarding: add missing tests to Makefile")
  50fe062c806e ("selftests: forwarding: new test, verify host mdb entries")
https://lore.kernel.org/all/20220502111539.0b7e4621@canb.auug.org.au/

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>nfc: replace improper check device_is_registered() in netlink related functions</title>
<updated>2022-05-01T12:26:05Z</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-04-29T12:45:50Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=da5c0f119203ad9728920456a0f52a6d850c01cd'/>
<id>urn:sha1:da5c0f119203ad9728920456a0f52a6d850c01cd</id>
<content type='text'>
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;
</content>
</entry>
<entry>
<title>NFC: NULL out the dev-&gt;rfkill to prevent UAF</title>
<updated>2022-04-13T11:22:05Z</updated>
<author>
<name>Lin Ma</name>
<email>linma@zju.edu.cn</email>
</author>
<published>2022-04-12T05:32:08Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=1b0e81416a24d6e9b8c2341e22e8bf48f8b8bfc9'/>
<id>urn:sha1:1b0e81416a24d6e9b8c2341e22e8bf48f8b8bfc9</id>
<content type='text'>
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;
</content>
</entry>
<entry>
<title>NFC: reorder the logic in nfc_{un,}register_device</title>
<updated>2021-11-18T04:17:05Z</updated>
<author>
<name>Lin Ma</name>
<email>linma@zju.edu.cn</email>
</author>
<published>2021-11-16T15:26:52Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=3e3b5dfcd16a3e254aab61bd1e8c417dd4503102'/>
<id>urn:sha1:3e3b5dfcd16a3e254aab61bd1e8c417dd4503102</id>
<content type='text'>
There is a potential UAF between the unregistration routine and the NFC
netlink operations.

The race that cause that UAF can be shown as below:

 (FREE)                      |  (USE)
nfcmrvl_nci_unregister_dev   |  nfc_genl_dev_up
  nci_close_device           |
  nci_unregister_device      |    nfc_get_device
    nfc_unregister_device    |    nfc_dev_up
      rfkill_destory         |
      device_del             |      rfkill_blocked
  ...                        |    ...

The root cause for this race is concluded below:
1. The rfkill_blocked (USE) in nfc_dev_up is supposed to be placed after
the device_is_registered check.
2. Since the netlink operations are possible just after the device_add
in nfc_register_device, the nfc_dev_up() can happen anywhere during the
rfkill creation process, which leads to data race.

This patch reorder these actions to permit
1. Once device_del is finished, the nfc_dev_up cannot dereference the
rfkill object.
2. The rfkill_register need to be placed after the device_add of nfc_dev
because the parent device need to be created first. So this patch keeps
the order but inject device_lock to prevent the data race.

Signed-off-by: Lin Ma &lt;linma@zju.edu.cn&gt;
Fixes: be055b2f89b5 ("NFC: RFKILL support")
Reviewed-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Reviewed-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Link: https://lore.kernel.org/r/20211116152652.19217-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>nfc: constify local pointer variables</title>
<updated>2021-07-30T15:22:52Z</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>krzysztof.kozlowski@canonical.com</email>
</author>
<published>2021-07-30T14:42:00Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=f2479c0a22948c5998938fa5bb9d98f9931791b7'/>
<id>urn:sha1:f2479c0a22948c5998938fa5bb9d98f9931791b7</id>
<content type='text'>
Few pointers to struct nfc_target and struct nfc_se can be made const.

Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>nfc: constify several pointers to u8, char and sk_buff</title>
<updated>2021-07-30T15:22:52Z</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>krzysztof.kozlowski@canonical.com</email>
</author>
<published>2021-07-30T14:41:59Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=3df40eb3a2ea58bf404a38f15a7a2768e4762cb0'/>
<id>urn:sha1:3df40eb3a2ea58bf404a38f15a7a2768e4762cb0</id>
<content type='text'>
Several functions receive pointers to u8, char or sk_buff but do not
modify the contents so make them const.  This allows doing the same for
local variables and in total makes the code a little bit safer.

Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>nfc: constify nfc_ops</title>
<updated>2021-07-25T08:21:21Z</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>krzysztof.kozlowski@canonical.com</email>
</author>
<published>2021-07-24T21:49:25Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=f6c802a726aea43a2937763f13560c1fd170fae6'/>
<id>urn:sha1:f6c802a726aea43a2937763f13560c1fd170fae6</id>
<content type='text'>
Neither the core nor the drivers modify the passed pointer to struct
nfc_ops, so make it a pointer to const for correctness and safety.

Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>net: nfc: Fix kerneldoc warnings</title>
<updated>2020-10-30T18:57:56Z</updated>
<author>
<name>Andrew Lunn</name>
<email>andrew@lunn.ch</email>
</author>
<published>2020-10-28T00:56:53Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=7cdda1c1c58d0c1686d41c2f789ea90bfef17709'/>
<id>urn:sha1:7cdda1c1c58d0c1686d41c2f789ea90bfef17709</id>
<content type='text'>
net//nfc/core.c:1046: warning: Function parameter or member 'tx_headroom' not described in 'nfc_allocate_device'
net//nfc/core.c:1046: warning: Function parameter or member 'tx_tailroom' not described in 'nfc_allocate_device'
net//nfc/core.c:198: warning: Excess function parameter 'protocols' description in 'nfc_start_poll'
net//nfc/core.c:198: warning: Function parameter or member 'im_protocols' not described in 'nfc_start_poll'
net//nfc/core.c:198: warning: Function parameter or member 'tm_protocols' not described in 'nfc_start_poll'
net//nfc/core.c:441: warning: Function parameter or member 'mode' not described in 'nfc_deactivate_target'
net//nfc/core.c:711: warning: Function parameter or member 'dev' not described in 'nfc_alloc_send_skb'
net//nfc/core.c:711: warning: Function parameter or member 'err' not described in 'nfc_alloc_send_skb'
net//nfc/core.c:711: warning: Function parameter or member 'flags' not described in 'nfc_alloc_send_skb'
net//nfc/core.c:711: warning: Function parameter or member 'sk' not described in 'nfc_alloc_send_skb'
net//nfc/digital_core.c:470: warning: Function parameter or member 'im_protocols' not described in 'digital_start_poll'
net//nfc/digital_core.c:470: warning: Function parameter or member 'nfc_dev' not described in 'digital_start_poll'
net//nfc/digital_core.c:470: warning: Function parameter or member 'tm_protocols' not described in 'digital_start_poll'
net//nfc/nci/core.c:1119: warning: Function parameter or member 'tx_headroom' not described in 'nci_allocate_device'
net//nfc/nci/core.c:1119: warning: Function parameter or member 'tx_tailroom' not described in 'nci_allocate_device'

Signed-off-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://lore.kernel.org/r/20201028005653.930467-1-andrew@lunn.ch
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: nfc: kerneldoc fixes</title>
<updated>2020-07-14T00:20:40Z</updated>
<author>
<name>Andrew Lunn</name>
<email>andrew@lunn.ch</email>
</author>
<published>2020-07-12T23:15:08Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=ffbab1c93b52b3405183eb3643664d8a2e9b38ea'/>
<id>urn:sha1:ffbab1c93b52b3405183eb3643664d8a2e9b38ea</id>
<content type='text'>
Simple fixes which require no deep knowledge of the code.

Signed-off-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
