<feed xmlns='http://www.w3.org/2005/Atom'>
<title>wireguard-linux/net/nfc/nci/uart.c, branch jd/unified-crypt-queue</title>
<subtitle>WireGuard for the Linux kernel</subtitle>
<id>https://git.zx2c4.com/wireguard-linux/atom/net/nfc/nci/uart.c?h=jd%2Funified-crypt-queue</id>
<link rel='self' href='https://git.zx2c4.com/wireguard-linux/atom/net/nfc/nci/uart.c?h=jd%2Funified-crypt-queue'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/'/>
<updated>2019-12-18T19:57:33Z</updated>
<entry>
<title>net: nfc: nci: fix a possible sleep-in-atomic-context bug in nci_uart_tty_receive()</title>
<updated>2019-12-18T19:57:33Z</updated>
<author>
<name>Jia-Ju Bai</name>
<email>baijiaju1990@gmail.com</email>
</author>
<published>2019-12-18T09:21:55Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=b7ac893652cafadcf669f78452329727e4e255cc'/>
<id>urn:sha1:b7ac893652cafadcf669f78452329727e4e255cc</id>
<content type='text'>
The kernel may sleep while holding a spinlock.
The function call path (from bottom to top) in Linux 4.19 is:

net/nfc/nci/uart.c, 349:
	nci_skb_alloc in nci_uart_default_recv_buf
net/nfc/nci/uart.c, 255:
	(FUNC_PTR)nci_uart_default_recv_buf in nci_uart_tty_receive
net/nfc/nci/uart.c, 254:
	spin_lock in nci_uart_tty_receive

nci_skb_alloc(GFP_KERNEL) can sleep at runtime.
(FUNC_PTR) means a function pointer is called.

To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC for
nci_skb_alloc().

This bug is found by a static analysis tool STCheck written by myself.

Signed-off-by: Jia-Ju Bai &lt;baijiaju1990@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge branch 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2018-10-24T13:43:41Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-10-24T13:43:41Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=44adbac8f7217040be97928cd19998259d9d4418'/>
<id>urn:sha1:44adbac8f7217040be97928cd19998259d9d4418</id>
<content type='text'>
Pull tty ioctl updates from Al Viro:
 "This is the compat_ioctl work related to tty ioctls.

  Quite a bit of dead code taken out, all tty-related stuff gone from
  fs/compat_ioctl.c. A bunch of compat bugs fixed - some still remain,
  but all more or less generic tty-related ioctls should be covered
  (remaining issues are in things like driver-private ioctls in a pcmcia
  serial card driver not getting properly handled in 32bit processes on
  64bit host, etc)"

* 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (53 commits)
  kill TIOCSERGSTRUCT
  change semantics of ldisc -&gt;compat_ioctl()
  kill TIOCSER[SG]WILD
  synclink_gt(): fix compat_ioctl()
  pty: fix compat ioctls
  compat_ioctl - kill keyboard ioctl handling
  gigaset: add -&gt;compat_ioctl()
  vt_compat_ioctl(): clean up, use compat_ptr() properly
  gigaset: don't try to printk userland buffer contents
  dgnc: don't bother with (empty) stub for TCXONC
  dgnc: leave TIOC[GS]SOFTCAR to ldisc
  remove fallback to drivers for TIOCGICOUNT
  dgnc: break-related ioctls won't reach -&gt;ioctl()
  kill the rest of tty COMPAT_IOCTL() entries
  dgnc: TIOCM... won't reach -&gt;ioctl()
  isdn_tty: TCSBRK{,P} won't reach -&gt;ioctl()
  kill capinc_tty_ioctl()
  take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()
  synclink: reduce pointless checks in -&gt;ioctl()
  complete -&gt;[sg]et_serial() switchover
  ...
</content>
</entry>
<entry>
<title>change semantics of ldisc -&gt;compat_ioctl()</title>
<updated>2018-10-13T04:50:53Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2018-09-14T02:12:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=f0193d3ea73b966b5dbfa272c8228d743b8856ef'/>
<id>urn:sha1:f0193d3ea73b966b5dbfa272c8228d743b8856ef</id>
<content type='text'>
First of all, make it return int.  Returning long when native method
had never allowed that is ridiculous and inconvenient.

More importantly, change the caller; if ldisc -&gt;compat_ioctl() is NULL
or returns -ENOIOCTLCMD, tty_compat_ioctl() will try to feed cmd and
compat_ptr(arg) to ldisc's native -&gt;ioctl().

That simplifies -&gt;compat_ioctl() instances quite a bit - they only
need to deal with ioctls that are neither generic tty ones (those
would get shunted off to tty_ioctl()) nor simple compat pointer ones.

Note that something like TCFLSH won't reach -&gt;compat_ioctl(),
even if ldisc -&gt;ioctl() does handle it - it will be recognized
earlier and passed to tty_ioctl() (and ultimately - ldisc -&gt;ioctl()).

For many ldiscs it means that NULL -&gt;compat_ioctl() does the
right thing.  Those where it won't serve (see e.g. n_r3964.c) are
also easily dealt with - we need to handle the numeric-argument
ioctls (calling the native instance) and, if such would exist,
the ioctls that need layout conversion, etc.

All in-tree ldiscs dealt with.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>net: nci: remove redundant null pointer check before kfree_skb</title>
<updated>2018-09-21T16:04:37Z</updated>
<author>
<name>zhong jiang</name>
<email>zhongjiang@huawei.com</email>
</author>
<published>2018-09-20T09:37:44Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=e3c3215e41f60f9debb17f920e4da7cb3a82a55b'/>
<id>urn:sha1:e3c3215e41f60f9debb17f920e4da7cb3a82a55b</id>
<content type='text'>
kfree_skb has taken the null pointer into account. hence it is safe
to remove the redundant null pointer check before kfree_skb.

Signed-off-by: zhong jiang &lt;zhongjiang@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>net: annotate -&gt;poll() instances</title>
<updated>2017-11-27T21:20:04Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2017-07-03T04:01:49Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=ade994f4f6c8c3ef4c3bfc2d02166262fb9d089c'/>
<id>urn:sha1:ade994f4f6c8c3ef4c3bfc2d02166262fb9d089c</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>networking: add and use skb_put_u8()</title>
<updated>2017-06-16T15:48:40Z</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2017-06-16T12:29:24Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=634fef61076d644b989b86abc2f560d81a089a31'/>
<id>urn:sha1:634fef61076d644b989b86abc2f560d81a089a31</id>
<content type='text'>
Joe and Bjørn suggested that it'd be nicer to not have the
cast in the fairly common case of doing
	*(u8 *)skb_put(skb, 1) = c;

Add skb_put_u8() for this case, and use it across the code,
using the following spatch:

    @@
    expression SKB, C, S;
    typedef u8;
    identifier fn = {skb_put};
    fresh identifier fn2 = fn ## "_u8";
    @@
    - *(u8 *)fn(SKB, S) = C;
    + fn2(SKB, C);

Note that due to the "S", the spatch isn't perfect, it should
have checked that S is 1, but there's also places that use a
sizeof expression like sizeof(var) or sizeof(u8) etc. Turns
out that nobody ever did something like
	*(u8 *)skb_put(skb, 2) = c;

which would be wrong anyway since the second byte wouldn't be
initialized.

Suggested-by: Joe Perches &lt;joe@perches.com&gt;
Suggested-by: Bjørn Mork &lt;bjorn@mork.no&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>networking: make skb_put &amp; friends return void pointers</title>
<updated>2017-06-16T15:48:39Z</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2017-06-16T12:29:21Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=4df864c1d9afb46e2461a9f808d9f11a42d31bad'/>
<id>urn:sha1:4df864c1d9afb46e2461a9f808d9f11a42d31bad</id>
<content type='text'>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>networking: introduce and use skb_put_data()</title>
<updated>2017-06-16T15:48:37Z</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2017-06-16T12:29:20Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=59ae1d127ac0ae404baf414c434ba2651b793f46'/>
<id>urn:sha1:59ae1d127ac0ae404baf414c434ba2651b793f46</id>
<content type='text'>
A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger &lt;stephen@networkplumber.org&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>NFC: nci: Remove dead code</title>
<updated>2016-01-27T23:01:44Z</updated>
<author>
<name>Peter Hurley</name>
<email>peter@hurleysoftware.com</email>
</author>
<published>2016-01-11T06:40:53Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=582e20a03b9bcbddaeaffb38800323ddcc4a9173'/>
<id>urn:sha1:582e20a03b9bcbddaeaffb38800323ddcc4a9173</id>
<content type='text'>
The N_NCI ldisc does not define a flush_buffer() ldisc method, so
the check when opening the ldisc is always false.

Signed-off-by: Peter Hurley &lt;peter@hurleysoftware.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>NFC: nci: fix mistake in uart generic driver</title>
<updated>2015-06-15T16:10:37Z</updated>
<author>
<name>Vincent Cuissard</name>
<email>cuissard@marvell.com</email>
</author>
<published>2015-06-15T15:34:23Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=fb77ff4f43990dc91926ce2704036a547482544e'/>
<id>urn:sha1:fb77ff4f43990dc91926ce2704036a547482544e</id>
<content type='text'>
It was not possible to register a UART driver due
to a bad condition.

Signed-off-by: Vincent Cuissard &lt;cuissard@marvell.com&gt;
Signed-off-by: Samuel Ortiz &lt;sameo@linux.intel.com&gt;
</content>
</entry>
</feed>
