<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux, branch v4.14.265</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.14.265</id>
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<updated>2022-02-08T17:16:26Z</updated>
<entry>
<title>net: fix information leakage in /proc/net/ptype</title>
<updated>2022-02-08T17:16:26Z</updated>
<author>
<name>Congyu Liu</name>
<email>liu3101@purdue.edu</email>
</author>
<published>2022-01-18T19:20:13Z</published>
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<content type='text'>
commit 47934e06b65637c88a762d9c98329ae6e3238888 upstream.

In one net namespace, after creating a packet socket without binding
it to a device, users in other net namespaces can observe the new
`packet_type` added by this packet socket by reading `/proc/net/ptype`
file. This is minor information leakage as packet socket is
namespace aware.

Add a net pointer in `packet_type` to keep the net namespace of
of corresponding packet socket. In `ptype_seq_show`, this net pointer
must be checked when it is not NULL.

Fixes: 2feb27dbe00c ("[NETNS]: Minor information leak via /proc/net/ptype file.")
Signed-off-by: Congyu Liu &lt;liu3101@purdue.edu&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: skip virtio_net_hdr_set_proto if protocol already set</title>
<updated>2021-12-29T11:17:33Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2021-12-20T14:50:27Z</published>
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<id>urn:sha1:e3843ad124e85777a7c039d811aa9b9958da232e</id>
<content type='text'>
[ Upstream commit 1ed1d592113959f00cc552c3b9f47ca2d157768f ]

virtio_net_hdr_set_proto infers skb-&gt;protocol from the virtio_net_hdr
gso_type, to avoid packets getting dropped for lack of a proto type.

Its protocol choice is a guess, especially in the case of UFO, where
the single VIRTIO_NET_HDR_GSO_UDP label covers both UFOv4 and UFOv6.

Skip this best effort if the field is already initialized. Whether
explicitly from userspace, or implicitly based on an earlier call to
dev_parse_header_protocol (which is more robust, but was introduced
after this patch).

Fixes: 9d2f67e43b73 ("net/packet: fix packet drop as of virtio gso")
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Link: https://lore.kernel.org/r/20211220145027.2784293-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: accept UFOv6 packages in virtio_net_hdr_to_skb</title>
<updated>2021-12-29T11:17:33Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2021-12-20T14:49:01Z</published>
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<id>urn:sha1:97399eb6cc50b356eadcf5ff7bdbc805a209f94f</id>
<content type='text'>
[ Upstream commit 7e5cced9ca84df52d874aca6b632f930b3dc5bc6 ]

Skb with skb-&gt;protocol 0 at the time of virtio_net_hdr_to_skb may have
a protocol inferred from virtio_net_hdr with virtio_net_hdr_set_proto.

Unlike TCP, UDP does not have separate types for IPv4 and IPv6. Type
VIRTIO_NET_HDR_GSO_UDP is guessed to be IPv4/UDP. As of the below
commit, UFOv6 packets are dropped due to not matching the protocol as
obtained from dev_parse_header_protocol.

Invert the test to take that L2 protocol field as starting point and
pass both UFOv4 and UFOv6 for VIRTIO_NET_HDR_GSO_UDP.

Fixes: 924a9bc362a5 ("net: check if protocol extracted by virtio_net_hdr_set_proto is correct")
Link: https://lore.kernel.org/netdev/CABcq3pG9GRCYqFDBAJ48H1vpnnX=41u+MhQnayF1ztLH4WX0Fw@mail.gmail.com/
Reported-by: Andrew Melnichenko &lt;andrew@daynix.com&gt;
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Link: https://lore.kernel.org/r/20211220144901.2784030-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>wait: add wake_up_pollfree()</title>
<updated>2021-12-14T09:16:55Z</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2021-12-11T00:19:24Z</published>
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<id>urn:sha1:a36e1978c6cb6282fadd5d62d4b3e7808cf0597b</id>
<content type='text'>
commit 42288cb44c4b5fff7653bc392b583a2b8bd6a8c0 upstream.

Several -&gt;poll() implementations are special in that they use a
waitqueue whose lifetime is the current task, rather than the struct
file as is normally the case.  This is okay for blocking polls, since a
blocking poll occurs within one task; however, non-blocking polls
require another solution.  This solution is for the queue to be cleared
before it is freed, using 'wake_up_poll(wq, EPOLLHUP | POLLFREE);'.

However, that has a bug: wake_up_poll() calls __wake_up() with
nr_exclusive=1.  Therefore, if there are multiple "exclusive" waiters,
and the wakeup function for the first one returns a positive value, only
that one will be called.  That's *not* what's needed for POLLFREE;
POLLFREE is special in that it really needs to wake up everyone.

Considering the three non-blocking poll systems:

- io_uring poll doesn't handle POLLFREE at all, so it is broken anyway.

- aio poll is unaffected, since it doesn't support exclusive waits.
  However, that's fragile, as someone could add this feature later.

- epoll doesn't appear to be broken by this, since its wakeup function
  returns 0 when it sees POLLFREE.  But this is fragile.

Although there is a workaround (see epoll), it's better to define a
function which always sends POLLFREE to all waiters.  Add such a
function.  Also make it verify that the queue really becomes empty after
all waiters have been woken up.

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211209010455.42744-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>HID: add hid_is_usb() function to make it simpler for USB detection</title>
<updated>2021-12-14T09:16:53Z</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2021-12-01T18:35:01Z</published>
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<content type='text'>
commit f83baa0cb6cfc92ebaf7f9d3a99d7e34f2e77a8a upstream.

A number of HID drivers already call hid_is_using_ll_driver() but only
for the detection of if this is a USB device or not.  Make this more
obvious by creating hid_is_usb() and calling the function that way.

Also converts the existing hid_is_using_ll_driver() functions to use the
new call.

Cc: Jiri Kosina &lt;jikos@kernel.org&gt;
Cc: Benjamin Tissoires &lt;benjamin.tissoires@redhat.com&gt;
Cc: linux-input@vger.kernel.org
Cc: stable@vger.kernel.org
Tested-by: Benjamin Tissoires &lt;benjamin.tissoires@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Benjamin Tissoires &lt;benjamin.tissoires@redhat.com&gt;
Link: https://lore.kernel.org/r/20211201183503.2373082-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>siphash: use _unaligned version by default</title>
<updated>2021-12-08T07:46:55Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2021-11-29T15:39:29Z</published>
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<id>urn:sha1:b1cd494e04e1466ab61662c0045b66a7a6eb7023</id>
<content type='text'>
commit f7e5b9bfa6c8820407b64eabc1f29c9a87e8993d upstream.

On ARM v6 and later, we define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
because the ordinary load/store instructions (ldr, ldrh, ldrb) can
tolerate any misalignment of the memory address. However, load/store
double and load/store multiple instructions (ldrd, ldm) may still only
be used on memory addresses that are 32-bit aligned, and so we have to
use the CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS macro with care, or we
may end up with a severe performance hit due to alignment traps that
require fixups by the kernel. Testing shows that this currently happens
with clang-13 but not gcc-11. In theory, any compiler version can
produce this bug or other problems, as we are dealing with undefined
behavior in C99 even on architectures that support this in hardware,
see also https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100363.

Fortunately, the get_unaligned() accessors do the right thing: when
building for ARMv6 or later, the compiler will emit unaligned accesses
using the ordinary load/store instructions (but avoid the ones that
require 32-bit alignment). When building for older ARM, those accessors
will emit the appropriate sequence of ldrb/mov/orr instructions. And on
architectures that can truly tolerate any kind of misalignment, the
get_unaligned() accessors resolve to the leXX_to_cpup accessors that
operate on aligned addresses.

Since the compiler will in fact emit ldrd or ldm instructions when
building this code for ARM v6 or later, the solution is to use the
unaligned accessors unconditionally on architectures where this is
known to be fast. The _aligned version of the hash function is
however still needed to get the best performance on architectures
that cannot do any unaligned access in hardware.

This new version avoids the undefined behavior and should produce
the fastest hash on all architectures we support.

Link: https://lore.kernel.org/linux-arm-kernel/20181008211554.5355-4-ard.biesheuvel@linaro.org/
Link: https://lore.kernel.org/linux-crypto/CAK8P3a2KfmmGDbVHULWevB0hv71P2oi2ZCHEAqT=8dQfa0=cqQ@mail.gmail.com/
Reported-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Fixes: 2c956a60778c ("siphash: add cryptographically secure PRF")
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: add fget_many() and fput_many()</title>
<updated>2021-12-08T07:46:55Z</updated>
<author>
<name>Jens Axboe</name>
<email>axboe@kernel.dk</email>
</author>
<published>2018-11-21T17:32:39Z</published>
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<id>urn:sha1:1d8e40836044aeff3192f072425ea19f5c5807eb</id>
<content type='text'>
commit 091141a42e15fe47ada737f3996b317072afcefb upstream.

Some uses cases repeatedly get and put references to the same file, but
the only exposed interface is doing these one at the time. As each of
these entail an atomic inc or dec on a shared structure, that cost can
add up.

Add fget_many(), which works just like fget(), except it takes an
argument for how many references to get on the file. Ditto fput_many(),
which can drop an arbitrary number of references to a file.

Reviewed-by: Hannes Reinecke &lt;hare@suse.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>kprobes: Limit max data_size of the kretprobe instances</title>
<updated>2021-12-08T07:46:54Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2021-12-01T14:45:50Z</published>
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<id>urn:sha1:2f16a42930c06e87807663dde2e9b3a77f5da6c8</id>
<content type='text'>
commit 6bbfa44116689469267f1a6e3d233b52114139d2 upstream.

The 'kprobe::data_size' is unsigned, thus it can not be negative.  But if
user sets it enough big number (e.g. (size_t)-8), the result of 'data_size
+ sizeof(struct kretprobe_instance)' becomes smaller than sizeof(struct
kretprobe_instance) or zero. In result, the kretprobe_instance are
allocated without enough memory, and kretprobe accesses outside of
allocated memory.

To avoid this issue, introduce a max limitation of the
kretprobe::data_size. 4KB per instance should be OK.

Link: https://lkml.kernel.org/r/163836995040.432120.10322772773821182925.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: f47cd9b553aa ("kprobes: kretprobe user entry-handler")
Reported-by: zhangyue &lt;zhangyue1@kylinos.cn&gt;
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>shm: extend forced shm destroy to support objects from several IPC nses</title>
<updated>2021-12-08T07:46:53Z</updated>
<author>
<name>Alexander Mikhalitsyn</name>
<email>alexander.mikhalitsyn@virtuozzo.com</email>
</author>
<published>2021-11-20T00:43:21Z</published>
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<id>urn:sha1:8619236d939f19fc8e177b17e8365a3ff16f9b0e</id>
<content type='text'>
commit 85b6d24646e4125c591639841169baa98a2da503 upstream.

Currently, the exit_shm() function not designed to work properly when
task-&gt;sysvshm.shm_clist holds shm objects from different IPC namespaces.

This is a real pain when sysctl kernel.shm_rmid_forced = 1, because it
leads to use-after-free (reproducer exists).

This is an attempt to fix the problem by extending exit_shm mechanism to
handle shm's destroy from several IPC ns'es.

To achieve that we do several things:

1. add a namespace (non-refcounted) pointer to the struct shmid_kernel

2. during new shm object creation (newseg()/shmget syscall) we
   initialize this pointer by current task IPC ns

3. exit_shm() fully reworked such that it traverses over all shp's in
   task-&gt;sysvshm.shm_clist and gets IPC namespace not from current task
   as it was before but from shp's object itself, then call
   shm_destroy(shp, ns).

Note: We need to be really careful here, because as it was said before
(1), our pointer to IPC ns non-refcnt'ed.  To be on the safe side we
using special helper get_ipc_ns_not_zero() which allows to get IPC ns
refcounter only if IPC ns not in the "state of destruction".

Q/A

Q: Why can we access shp-&gt;ns memory using non-refcounted pointer?
A: Because shp object lifetime is always shorther than IPC namespace
   lifetime, so, if we get shp object from the task-&gt;sysvshm.shm_clist
   while holding task_lock(task) nobody can steal our namespace.

Q: Does this patch change semantics of unshare/setns/clone syscalls?
A: No. It's just fixes non-covered case when process may leave IPC
   namespace without getting task-&gt;sysvshm.shm_clist list cleaned up.

Link: https://lkml.kernel.org/r/67bb03e5-f79c-1815-e2bf-949c67047418@colorfullife.com
Link: https://lkml.kernel.org/r/20211109151501.4921-1-manfred@colorfullife.com
Fixes: ab602f79915 ("shm: make exit_shm work proportional to task activity")
Co-developed-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Signed-off-by: Alexander Mikhalitsyn &lt;alexander.mikhalitsyn@virtuozzo.com&gt;
Cc: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Greg KH &lt;gregkh@linuxfoundation.org&gt;
Cc: Andrei Vagin &lt;avagin@gmail.com&gt;
Cc: Pavel Tikhomirov &lt;ptikhomirov@virtuozzo.com&gt;
Cc: Vasily Averin &lt;vvs@virtuozzo.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
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>net: virtio_net_hdr_to_skb: count transport header in UFO</title>
<updated>2021-11-26T10:40:40Z</updated>
<author>
<name>Jonathan Davies</name>
<email>jonathan.davies@nutanix.com</email>
</author>
<published>2021-11-16T17:42:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2128303bff700c857739a0af8cc39c1a41840650'/>
<id>urn:sha1:2128303bff700c857739a0af8cc39c1a41840650</id>
<content type='text'>
[ Upstream commit cf9acc90c80ecbee00334aa85d92f4e74014bcff ]

virtio_net_hdr_to_skb does not set the skb's gso_size and gso_type
correctly for UFO packets received via virtio-net that are a little over
the GSO size. This can lead to problems elsewhere in the networking
stack, e.g. ovs_vport_send dropping over-sized packets if gso_size is
not set.

This is due to the comparison

  if (skb-&gt;len - p_off &gt; gso_size)

not properly accounting for the transport layer header.

p_off includes the size of the transport layer header (thlen), so
skb-&gt;len - p_off is the size of the TCP/UDP payload.

gso_size is read from the virtio-net header. For UFO, fragmentation
happens at the IP level so does not need to include the UDP header.

Hence the calculation could be comparing a TCP/UDP payload length with
an IP payload length, causing legitimate virtio-net packets to have
lack gso_type/gso_size information.

Example: a UDP packet with payload size 1473 has IP payload size 1481.
If the guest used UFO, it is not fragmented and the virtio-net header's
flags indicate that it is a GSO frame (VIRTIO_NET_HDR_GSO_UDP), with
gso_size = 1480 for an MTU of 1500.  skb-&gt;len will be 1515 and p_off
will be 42, so skb-&gt;len - p_off = 1473.  Hence the comparison fails, and
shinfo-&gt;gso_size and gso_type are not set as they should be.

Instead, add the UDP header length before comparing to gso_size when
using UFO. In this way, it is the size of the IP payload that is
compared to gso_size.

Fixes: 6dd912f82680 ("net: check untrusted gso_size at kernel entry")
Signed-off-by: Jonathan Davies &lt;jonathan.davies@nutanix.com&gt;
Reviewed-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
