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<title>user/sven/linux.git/include, branch v4.19.124</title>
<subtitle>Linux Kernel
</subtitle>
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<updated>2020-05-20T06:18:49Z</updated>
<entry>
<title>x86: Fix early boot crash on gcc-10, third try</title>
<updated>2020-05-20T06:18:49Z</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2020-04-22T16:11:30Z</published>
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<content type='text'>
commit a9a3ed1eff3601b63aea4fb462d8b3b92c7c1e7e upstream.

... or the odyssey of trying to disable the stack protector for the
function which generates the stack canary value.

The whole story started with Sergei reporting a boot crash with a kernel
built with gcc-10:

  Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary
  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139
  Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013
  Call Trace:
    dump_stack
    panic
    ? start_secondary
    __stack_chk_fail
    start_secondary
    secondary_startup_64
  -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary

This happens because gcc-10 tail-call optimizes the last function call
in start_secondary() - cpu_startup_entry() - and thus emits a stack
canary check which fails because the canary value changes after the
boot_init_stack_canary() call.

To fix that, the initial attempt was to mark the one function which
generates the stack canary with:

  __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused)

however, using the optimize attribute doesn't work cumulatively
as the attribute does not add to but rather replaces previously
supplied optimization options - roughly all -fxxx options.

The key one among them being -fno-omit-frame-pointer and thus leading to
not present frame pointer - frame pointer which the kernel needs.

The next attempt to prevent compilers from tail-call optimizing
the last function call cpu_startup_entry(), shy of carving out
start_secondary() into a separate compilation unit and building it with
-fno-stack-protector, was to add an empty asm("").

This current solution was short and sweet, and reportedly, is supported
by both compilers but we didn't get very far this time: future (LTO?)
optimization passes could potentially eliminate this, which leads us
to the third attempt: having an actual memory barrier there which the
compiler cannot ignore or move around etc.

That should hold for a long time, but hey we said that about the other
two solutions too so...

Reported-by: Sergei Trofimovich &lt;slyfox@gentoo.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Tested-by: Kalle Valo &lt;kvalo@codeaurora.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>ALSA: rawmidi: Fix racy buffer resize under concurrent accesses</title>
<updated>2020-05-20T06:18:47Z</updated>
<author>
<name>Takashi Iwai</name>
<email>tiwai@suse.de</email>
</author>
<published>2020-05-07T11:44:56Z</published>
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<id>urn:sha1:a507658fdb2ad8ca282b0eb42f2a40b805deb1e6</id>
<content type='text'>
commit c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d upstream.

The rawmidi core allows user to resize the runtime buffer via ioctl,
and this may lead to UAF when performed during concurrent reads or
writes: the read/write functions unlock the runtime lock temporarily
during copying form/to user-space, and that's the race window.

This patch fixes the hole by introducing a reference counter for the
runtime buffer read/write access and returns -EBUSY error when the
resize is performed concurrently against read/write.

Note that the ref count field is a simple integer instead of
refcount_t here, since the all contexts accessing the buffer is
basically protected with a spinlock, hence we need no expensive atomic
ops.  Also, note that this busy check is needed only against read /
write functions, and not in receive/transmit callbacks; the race can
happen only at the spinlock hole mentioned in the above, while the
whole function is protected for receive / transmit callbacks.

Reported-by: butt3rflyh4ck &lt;butterflyhuangxx@gmail.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/CAFcO6XMWpUVK_yzzCpp8_XP7+=oUpQvuBeCbMffEDkpe8jWrfg@mail.gmail.com
Link: https://lore.kernel.org/r/s5heerw3r5z.wl-tiwai@suse.de
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>gcc-10 warnings: fix low-hanging fruit</title>
<updated>2020-05-20T06:18:45Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-05-04T16:16:37Z</published>
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<content type='text'>
commit 9d82973e032e246ff5663c9805fbb5407ae932e3 upstream.

Due to a bug-report that was compiler-dependent, I updated one of my
machines to gcc-10.  That shows a lot of new warnings.  Happily they
seem to be mostly the valid kind, but it's going to cause a round of
churn for getting rid of them..

This is the really low-hanging fruit of removing a couple of zero-sized
arrays in some core code.  We have had a round of these patches before,
and we'll have many more coming, and there is nothing special about
these except that they were particularly trivial, and triggered more
warnings than most.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>pnp: Use list_for_each_entry() instead of open coding</title>
<updated>2020-05-20T06:18:45Z</updated>
<author>
<name>Jason Gunthorpe</name>
<email>jgg@mellanox.com</email>
</author>
<published>2020-04-14T15:10:50Z</published>
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<id>urn:sha1:bd2cefcd8815fc4f6dd5226065ac20e613e007b4</id>
<content type='text'>
commit 01b2bafe57b19d9119413f138765ef57990921ce upstream.

Aside from good practice, this avoids a warning from gcc 10:

./include/linux/kernel.h:997:3: warning: array subscript -31 is outside array bounds of ‘struct list_head[1]’ [-Warray-bounds]
  997 |  ((type *)(__mptr - offsetof(type, member))); })
      |  ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/list.h:493:2: note: in expansion of macro ‘container_of’
  493 |  container_of(ptr, type, member)
      |  ^~~~~~~~~~~~
./include/linux/pnp.h:275:30: note: in expansion of macro ‘list_entry’
  275 | #define global_to_pnp_dev(n) list_entry(n, struct pnp_dev, global_list)
      |                              ^~~~~~~~~~
./include/linux/pnp.h:281:11: note: in expansion of macro ‘global_to_pnp_dev’
  281 |  (dev) != global_to_pnp_dev(&amp;pnp_global); \
      |           ^~~~~~~~~~~~~~~~~
arch/x86/kernel/rtc.c:189:2: note: in expansion of macro ‘pnp_for_each_dev’
  189 |  pnp_for_each_dev(dev) {

Because the common code doesn't cast the starting list_head to the
containing struct.

Signed-off-by: Jason Gunthorpe &lt;jgg@mellanox.com&gt;
[ rjw: Whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>netfilter: conntrack: avoid gcc-10 zero-length-bounds warning</title>
<updated>2020-05-20T06:18:43Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2020-04-30T21:30:48Z</published>
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<id>urn:sha1:d2413ec1f789f6e21134ff895cd47b5b82613b99</id>
<content type='text'>
[ Upstream commit 2c407aca64977ede9b9f35158e919773cae2082f ]

gcc-10 warns around a suspicious access to an empty struct member:

net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc':
net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds]
 1522 |  memset(&amp;ct-&gt;__nfct_init_offset[0], 0,
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from net/netfilter/nf_conntrack_core.c:37:
include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset'
   90 |  u8 __nfct_init_offset[0];
      |     ^~~~~~~~~~~~~~~~~~

The code is correct but a bit unusual. Rework it slightly in a way that
does not trigger the warning, using an empty struct instead of an empty
array. There are probably more elegant ways to do this, but this is the
smallest change.

Fixes: c41884ce0562 ("netfilter: conntrack: avoid zeroing timer")
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tcp: fix SO_RCVLOWAT hangs with fat skbs</title>
<updated>2020-05-20T06:18:38Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2020-05-12T13:54:30Z</published>
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<id>urn:sha1:99779c24bf4c2b56129df5891902eb4e9a62f275</id>
<content type='text'>
[ Upstream commit 24adbc1676af4e134e709ddc7f34cf2adc2131e4 ]

We autotune rcvbuf whenever SO_RCVLOWAT is set to account for 100%
overhead in tcp_set_rcvlowat()

This works well when skb-&gt;len/skb-&gt;truesize ratio is bigger than 0.5

But if we receive packets with small MSS, we can end up in a situation
where not enough bytes are available in the receive queue to satisfy
RCVLOWAT setting.
As our sk_rcvbuf limit is hit, we send zero windows in ACK packets,
preventing remote peer from sending more data.

Even autotuning does not help, because it only triggers at the time
user process drains the queue. If no EPOLLIN is generated, this
can not happen.

Note poll() has a similar issue, after commit
c7004482e8dc ("tcp: Respect SO_RCVLOWAT in tcp_poll().")

Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: stricter validation of untrusted gso packets</title>
<updated>2020-05-14T05:57:19Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2020-05-04T16:48:54Z</published>
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<content type='text'>
[ Upstream commit 9274124f023b5c56dc4326637d4f787968b03607 ]

Syzkaller again found a path to a kernel crash through bad gso input:
a packet with transport header extending beyond skb_headlen(skb).

Tighten validation at kernel entry:

- Verify that the transport header lies within the linear section.

    To avoid pulling linux/tcp.h, verify just sizeof tcphdr.
    tcp_gso_segment will call pskb_may_pull (th-&gt;doff * 4) before use.

- Match the gso_type against the ip_proto found by the flow dissector.

Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mac80211: add ieee80211_is_any_nullfunc()</title>
<updated>2020-05-10T08:30:12Z</updated>
<author>
<name>Thomas Pedersen</name>
<email>thomas@adapt-ip.com</email>
</author>
<published>2020-01-14T05:59:40Z</published>
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<id>urn:sha1:2f83c2cce5fb07752b8eb0bcbae704c42566bb44</id>
<content type='text'>
commit 30b2f0be23fb40e58d0ad2caf8702c2a44cda2e1 upstream.

commit 08a5bdde3812 ("mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED")
Fixed a bug where we failed to take into account a
nullfunc frame can be either non-QoS or QoS. It turns out
there is at least one more bug in
ieee80211_sta_tx_notify(), introduced in
commit 7b6ddeaf27ec ("mac80211: use QoS NDP for AP probing"),
where we forgot to check for the QoS variant and so
assumed the QoS nullfunc frame never went out

Fix this by adding a helper ieee80211_is_any_nullfunc()
which consolidates the check for non-QoS and QoS nullfunc
frames. Replace existing compound conditionals and add a
couple more missing checks for QoS variant.

Signed-off-by: Thomas Pedersen &lt;thomas@adapt-ip.com&gt;
Link: https://lore.kernel.org/r/20200114055940.18502-3-thomas@adapt-ip.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>lib: devres: add a helper function for ioremap_uc</title>
<updated>2020-05-10T08:30:11Z</updated>
<author>
<name>Tuowen Zhao</name>
<email>ztuowen@gmail.com</email>
</author>
<published>2019-10-16T21:06:28Z</published>
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<id>urn:sha1:ccc4433062ce800ec03f573c156b893148fcf2c6</id>
<content type='text'>
[ Upstream commit e537654b7039aacfe8ae629d49655c0e5692ad44 ]

Implement a resource managed strongly uncachable ioremap function.

Cc: &lt;stable@vger.kernel.org&gt; # v4.19+
Tested-by: AceLan Kao &lt;acelan.kao@canonical.com&gt;
Signed-off-by: Tuowen Zhao &lt;ztuowen@gmail.com&gt;
Acked-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Acked-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Acked-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>qed: Fix use after free in qed_chain_free</title>
<updated>2020-05-02T15:26:00Z</updated>
<author>
<name>Yuval Basson</name>
<email>ybason@marvell.com</email>
</author>
<published>2020-03-29T17:32:49Z</published>
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<id>urn:sha1:64325c2855567e9324c3dff7bf343d7faa2f8e95</id>
<content type='text'>
commit 8063f761cd7c17fc1d0018728936e0c33a25388a upstream.

The qed_chain data structure was modified in
commit 1a4a69751f4d ("qed: Chain support for external PBL") to support
receiving an external pbl (due to iWARP FW requirements).
The pages pointed to by the pbl are allocated in qed_chain_alloc
and their virtual address are stored in an virtual addresses array to
enable accessing and freeing the data. The physical addresses however
weren't stored and were accessed directly from the external-pbl
during free.

Destroy-qp flow, leads to freeing the external pbl before the chain is
freed, when the chain is freed it tries accessing the already freed
external pbl, leading to a use-after-free. Therefore we need to store
the physical addresses in additional to the virtual addresses in a
new data structure.

Fixes: 1a4a69751f4d ("qed: Chain support for external PBL")
Signed-off-by: Michal Kalderon &lt;mkalderon@marvell.com&gt;
Signed-off-by: Yuval Bason &lt;ybason@marvell.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
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