<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include/linux, branch linux-4.1.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>mtd: cfi: cmdset_0001: Do not allow read/write to suspend erase block.</title>
<updated>2018-05-23T01:36:38+00:00</updated>
<author>
<name>Joakim Tjernlund</name>
<email>joakim.tjernlund@transmode.se</email>
</author>
<published>2018-03-01T13:39:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=52b254df5975fc40acdbfc4bdf4206c39bd0e7ea'/>
<id>52b254df5975fc40acdbfc4bdf4206c39bd0e7ea</id>
<content type='text'>
[ Upstream commit 6510bbc88e3258631831ade49033537081950605 ]

Currently it is possible to read and/or write to suspend EB's.
Writing /dev/mtdX or /dev/mtdblockX from several processes may
break the flash state machine.

Signed-off-by: Joakim Tjernlund &lt;joakim.tjernlund@infinera.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Reviewed-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Boris Brezillon &lt;boris.brezillon@bootlin.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6510bbc88e3258631831ade49033537081950605 ]

Currently it is possible to read and/or write to suspend EB's.
Writing /dev/mtdX or /dev/mtdblockX from several processes may
break the flash state machine.

Signed-off-by: Joakim Tjernlund &lt;joakim.tjernlund@infinera.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Reviewed-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Boris Brezillon &lt;boris.brezillon@bootlin.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: Don't call panic() at tty_ldisc_init()</title>
<updated>2018-05-23T01:36:38+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@I-love.SAKURA.ne.jp</email>
</author>
<published>2018-04-05T10:40:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=26834e6a6d4653db4bbb19a0bddf5a2620ea9c47'/>
<id>26834e6a6d4653db4bbb19a0bddf5a2620ea9c47</id>
<content type='text'>
[ Upstream commit 903f9db10f18f735e62ba447147b6c434b6af003 ]

syzbot is reporting kernel panic [1] triggered by memory allocation failure
at tty_ldisc_get() from tty_ldisc_init(). But since both tty_ldisc_get()
and caller of tty_ldisc_init() can cleanly handle errors, tty_ldisc_init()
does not need to call panic() when tty_ldisc_get() failed.

[1] https://syzkaller.appspot.com/bug?id=883431818e036ae6a9981156a64b821110f39187

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Jiri Slaby &lt;jslaby@suse.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 903f9db10f18f735e62ba447147b6c434b6af003 ]

syzbot is reporting kernel panic [1] triggered by memory allocation failure
at tty_ldisc_get() from tty_ldisc_init(). But since both tty_ldisc_get()
and caller of tty_ldisc_init() can cleanly handle errors, tty_ldisc_init()
does not need to call panic() when tty_ldisc_get() failed.

[1] https://syzkaller.appspot.com/bug?id=883431818e036ae6a9981156a64b821110f39187

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Jiri Slaby &lt;jslaby@suse.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>virtio: add ability to iterate over vqs</title>
<updated>2018-05-23T01:36:37+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2018-04-20T17:22:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=851c5371237bd1826790c16d9a639af56360cad6'/>
<id>851c5371237bd1826790c16d9a639af56360cad6</id>
<content type='text'>
[ Upstream commit 24a7e4d20783c0514850f24a5c41ede46ab058f0 ]

For cleanup it's helpful to be able to simply scan all vqs and discard
all data. Add an iterator to do that.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 24a7e4d20783c0514850f24a5c41ede46ab058f0 ]

For cleanup it's helpful to be able to simply scan all vqs and discard
all data. Add an iterator to do that.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vlan: Fix reading memory beyond skb-&gt;tail in skb_vlan_tagged_multi</title>
<updated>2018-05-23T01:36:36+00:00</updated>
<author>
<name>Toshiaki Makita</name>
<email>makita.toshiaki@lab.ntt.co.jp</email>
</author>
<published>2018-04-17T09:46:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e368e772ea984ad2e6c37277163178c2d4932a31'/>
<id>e368e772ea984ad2e6c37277163178c2d4932a31</id>
<content type='text'>
[ Upstream commit 7ce2367254e84753bceb07327aaf5c953cfce117 ]

Syzkaller spotted an old bug which leads to reading skb beyond tail by 4
bytes on vlan tagged packets.
This is caused because skb_vlan_tagged_multi() did not check
skb_headlen.

BUG: KMSAN: uninit-value in eth_type_vlan include/linux/if_vlan.h:283 [inline]
BUG: KMSAN: uninit-value in skb_vlan_tagged_multi include/linux/if_vlan.h:656 [inline]
BUG: KMSAN: uninit-value in vlan_features_check include/linux/if_vlan.h:672 [inline]
BUG: KMSAN: uninit-value in dflt_features_check net/core/dev.c:2949 [inline]
BUG: KMSAN: uninit-value in netif_skb_features+0xd1b/0xdc0 net/core/dev.c:3009
CPU: 1 PID: 3582 Comm: syzkaller435149 Not tainted 4.16.0+ #82
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0x185/0x1d0 lib/dump_stack.c:53
  kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
  __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
  eth_type_vlan include/linux/if_vlan.h:283 [inline]
  skb_vlan_tagged_multi include/linux/if_vlan.h:656 [inline]
  vlan_features_check include/linux/if_vlan.h:672 [inline]
  dflt_features_check net/core/dev.c:2949 [inline]
  netif_skb_features+0xd1b/0xdc0 net/core/dev.c:3009
  validate_xmit_skb+0x89/0x1320 net/core/dev.c:3084
  __dev_queue_xmit+0x1cb2/0x2b60 net/core/dev.c:3549
  dev_queue_xmit+0x4b/0x60 net/core/dev.c:3590
  packet_snd net/packet/af_packet.c:2944 [inline]
  packet_sendmsg+0x7c57/0x8a10 net/packet/af_packet.c:2969
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg net/socket.c:640 [inline]
  sock_write_iter+0x3b9/0x470 net/socket.c:909
  do_iter_readv_writev+0x7bb/0x970 include/linux/fs.h:1776
  do_iter_write+0x30d/0xd40 fs/read_write.c:932
  vfs_writev fs/read_write.c:977 [inline]
  do_writev+0x3c9/0x830 fs/read_write.c:1012
  SYSC_writev+0x9b/0xb0 fs/read_write.c:1085
  SyS_writev+0x56/0x80 fs/read_write.c:1082
  do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43ffa9
RSP: 002b:00007fff2cff3948 EFLAGS: 00000217 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ffa9
RDX: 0000000000000001 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000217 R12: 00000000004018d0
R13: 0000000000401960 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
  kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
  kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
  kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
  kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
  slab_post_alloc_hook mm/slab.h:445 [inline]
  slab_alloc_node mm/slub.c:2737 [inline]
  __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
  __kmalloc_reserve net/core/skbuff.c:138 [inline]
  __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
  alloc_skb include/linux/skbuff.h:984 [inline]
  alloc_skb_with_frags+0x1d4/0xb20 net/core/skbuff.c:5234
  sock_alloc_send_pskb+0xb56/0x1190 net/core/sock.c:2085
  packet_alloc_skb net/packet/af_packet.c:2803 [inline]
  packet_snd net/packet/af_packet.c:2894 [inline]
  packet_sendmsg+0x6444/0x8a10 net/packet/af_packet.c:2969
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg net/socket.c:640 [inline]
  sock_write_iter+0x3b9/0x470 net/socket.c:909
  do_iter_readv_writev+0x7bb/0x970 include/linux/fs.h:1776
  do_iter_write+0x30d/0xd40 fs/read_write.c:932
  vfs_writev fs/read_write.c:977 [inline]
  do_writev+0x3c9/0x830 fs/read_write.c:1012
  SYSC_writev+0x9b/0xb0 fs/read_write.c:1085
  SyS_writev+0x56/0x80 fs/read_write.c:1082
  do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: 58e998c6d239 ("offloading: Force software GSO for multiple vlan tags.")
Reported-and-tested-by: syzbot+0bbe42c764feafa82c5a@syzkaller.appspotmail.com
Signed-off-by: Toshiaki Makita &lt;makita.toshiaki@lab.ntt.co.jp&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7ce2367254e84753bceb07327aaf5c953cfce117 ]

Syzkaller spotted an old bug which leads to reading skb beyond tail by 4
bytes on vlan tagged packets.
This is caused because skb_vlan_tagged_multi() did not check
skb_headlen.

BUG: KMSAN: uninit-value in eth_type_vlan include/linux/if_vlan.h:283 [inline]
BUG: KMSAN: uninit-value in skb_vlan_tagged_multi include/linux/if_vlan.h:656 [inline]
BUG: KMSAN: uninit-value in vlan_features_check include/linux/if_vlan.h:672 [inline]
BUG: KMSAN: uninit-value in dflt_features_check net/core/dev.c:2949 [inline]
BUG: KMSAN: uninit-value in netif_skb_features+0xd1b/0xdc0 net/core/dev.c:3009
CPU: 1 PID: 3582 Comm: syzkaller435149 Not tainted 4.16.0+ #82
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0x185/0x1d0 lib/dump_stack.c:53
  kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
  __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
  eth_type_vlan include/linux/if_vlan.h:283 [inline]
  skb_vlan_tagged_multi include/linux/if_vlan.h:656 [inline]
  vlan_features_check include/linux/if_vlan.h:672 [inline]
  dflt_features_check net/core/dev.c:2949 [inline]
  netif_skb_features+0xd1b/0xdc0 net/core/dev.c:3009
  validate_xmit_skb+0x89/0x1320 net/core/dev.c:3084
  __dev_queue_xmit+0x1cb2/0x2b60 net/core/dev.c:3549
  dev_queue_xmit+0x4b/0x60 net/core/dev.c:3590
  packet_snd net/packet/af_packet.c:2944 [inline]
  packet_sendmsg+0x7c57/0x8a10 net/packet/af_packet.c:2969
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg net/socket.c:640 [inline]
  sock_write_iter+0x3b9/0x470 net/socket.c:909
  do_iter_readv_writev+0x7bb/0x970 include/linux/fs.h:1776
  do_iter_write+0x30d/0xd40 fs/read_write.c:932
  vfs_writev fs/read_write.c:977 [inline]
  do_writev+0x3c9/0x830 fs/read_write.c:1012
  SYSC_writev+0x9b/0xb0 fs/read_write.c:1085
  SyS_writev+0x56/0x80 fs/read_write.c:1082
  do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43ffa9
RSP: 002b:00007fff2cff3948 EFLAGS: 00000217 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ffa9
RDX: 0000000000000001 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000217 R12: 00000000004018d0
R13: 0000000000401960 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
  kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
  kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
  kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
  kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
  slab_post_alloc_hook mm/slab.h:445 [inline]
  slab_alloc_node mm/slub.c:2737 [inline]
  __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
  __kmalloc_reserve net/core/skbuff.c:138 [inline]
  __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
  alloc_skb include/linux/skbuff.h:984 [inline]
  alloc_skb_with_frags+0x1d4/0xb20 net/core/skbuff.c:5234
  sock_alloc_send_pskb+0xb56/0x1190 net/core/sock.c:2085
  packet_alloc_skb net/packet/af_packet.c:2803 [inline]
  packet_snd net/packet/af_packet.c:2894 [inline]
  packet_sendmsg+0x6444/0x8a10 net/packet/af_packet.c:2969
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg net/socket.c:640 [inline]
  sock_write_iter+0x3b9/0x470 net/socket.c:909
  do_iter_readv_writev+0x7bb/0x970 include/linux/fs.h:1776
  do_iter_write+0x30d/0xd40 fs/read_write.c:932
  vfs_writev fs/read_write.c:977 [inline]
  do_writev+0x3c9/0x830 fs/read_write.c:1012
  SYSC_writev+0x9b/0xb0 fs/read_write.c:1085
  SyS_writev+0x56/0x80 fs/read_write.c:1082
  do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: 58e998c6d239 ("offloading: Force software GSO for multiple vlan tags.")
Reported-and-tested-by: syzbot+0bbe42c764feafa82c5a@syzkaller.appspotmail.com
Signed-off-by: Toshiaki Makita &lt;makita.toshiaki@lab.ntt.co.jp&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>HID: core: Fix size as type u32</title>
<updated>2018-05-23T01:36:33+00:00</updated>
<author>
<name>Aaron Ma</name>
<email>aaron.ma@canonical.com</email>
</author>
<published>2018-01-08T02:41:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0f97219d779a39c85843b69f13cdfc81a457a059'/>
<id>0f97219d779a39c85843b69f13cdfc81a457a059</id>
<content type='text'>
[ Upstream commit 6de0b13cc0b4ba10e98a9263d7a83b940720b77a ]

When size is negative, calling memset will make segment fault.
Declare the size as type u32 to keep memset safe.

size in struct hid_report is unsigned, fix return type of
hid_report_len to u32.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma &lt;aaron.ma@canonical.com&gt;
Signed-off-by: Jiri Kosina &lt;jkosina@suse.cz&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6de0b13cc0b4ba10e98a9263d7a83b940720b77a ]

When size is negative, calling memset will make segment fault.
Declare the size as type u32 to keep memset safe.

size in struct hid_report is unsigned, fix return type of
hid_report_len to u32.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma &lt;aaron.ma@canonical.com&gt;
Signed-off-by: Jiri Kosina &lt;jkosina@suse.cz&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: make n_tty_read() always abort if hangup is in progress</title>
<updated>2018-05-23T01:36:32+00:00</updated>
<author>
<name>Tejun Heo</name>
<email>tj@kernel.org</email>
</author>
<published>2018-02-13T15:38:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=27c07e3cdc0bb455de146b776bb6f3d19850ccd2'/>
<id>27c07e3cdc0bb455de146b776bb6f3d19850ccd2</id>
<content type='text'>
[ Upstream commit 28b0f8a6962a24ed21737578f3b1b07424635c9e ]

A tty is hung up by __tty_hangup() setting file-&gt;f_op to
hung_up_tty_fops, which is skipped on ttys whose write operation isn't
tty_write().  This means that, for example, /dev/console whose write
op is redirected_tty_write() is never actually marked hung up.

Because n_tty_read() uses the hung up status to decide whether to
abort the waiting readers, the lack of hung-up marking can lead to the
following scenario.

 1. A session contains two processes.  The leader and its child.  The
    child ignores SIGHUP.

 2. The leader exits and starts disassociating from the controlling
    terminal (/dev/console).

 3. __tty_hangup() skips setting f_op to hung_up_tty_fops.

 4. SIGHUP is delivered and ignored.

 5. tty_ldisc_hangup() is invoked.  It wakes up the waits which should
    clear the read lockers of tty-&gt;ldisc_sem.

 6. The reader wakes up but because tty_hung_up_p() is false, it
    doesn't abort and goes back to sleep while read-holding
    tty-&gt;ldisc_sem.

 7. The leader progresses to tty_ldisc_lock() in tty_ldisc_hangup()
    and is now stuck in D sleep indefinitely waiting for
    tty-&gt;ldisc_sem.

The following is Alan's explanation on why some ttys aren't hung up.

 http://lkml.kernel.org/r/20171101170908.6ad08580@alans-desktop

 1. It broke the serial consoles because they would hang up and close
    down the hardware. With tty_port that *should* be fixable properly
    for any cases remaining.

 2. The console layer was (and still is) completely broken and doens't
    refcount properly. So if you turn on console hangups it breaks (as
    indeed does freeing consoles and half a dozen other things).

As neither can be fixed quickly, this patch works around the problem
by introducing a new flag, TTY_HUPPING, which is used solely to tell
n_tty_read() that hang-up is in progress for the console and the
readers should be aborted regardless of the hung-up status of the
device.

The following is a sample hung task warning caused by this issue.

  INFO: task agetty:2662 blocked for more than 120 seconds.
        Not tainted 4.11.3-dbg-tty-lockup-02478-gfd6c7ee-dirty #28
  "echo 0 &gt; /proc/sys/kernel/hung_task_timeout_secs" disables this message.
      0  2662      1 0x00000086
  Call Trace:
   __schedule+0x267/0x890
   schedule+0x36/0x80
   schedule_timeout+0x23c/0x2e0
   ldsem_down_write+0xce/0x1f6
   tty_ldisc_lock+0x16/0x30
   tty_ldisc_hangup+0xb3/0x1b0
   __tty_hangup+0x300/0x410
   disassociate_ctty+0x6c/0x290
   do_exit+0x7ef/0xb00
   do_group_exit+0x3f/0xa0
   get_signal+0x1b3/0x5d0
   do_signal+0x28/0x660
   exit_to_usermode_loop+0x46/0x86
   do_syscall_64+0x9c/0xb0
   entry_SYSCALL64_slow_path+0x25/0x25

The following is the repro.  Run "$PROG /dev/console".  The parent
process hangs in D state.

  #include &lt;sys/types.h&gt;
  #include &lt;sys/stat.h&gt;
  #include &lt;sys/wait.h&gt;
  #include &lt;sys/ioctl.h&gt;
  #include &lt;fcntl.h&gt;
  #include &lt;unistd.h&gt;
  #include &lt;stdio.h&gt;
  #include &lt;stdlib.h&gt;
  #include &lt;errno.h&gt;
  #include &lt;signal.h&gt;
  #include &lt;time.h&gt;
  #include &lt;termios.h&gt;

  int main(int argc, char **argv)
  {
	  struct sigaction sact = { .sa_handler = SIG_IGN };
	  struct timespec ts1s = { .tv_sec = 1 };
	  pid_t pid;
	  int fd;

	  if (argc &lt; 2) {
		  fprintf(stderr, "test-hung-tty /dev/$TTY\n");
		  return 1;
	  }

	  /* fork a child to ensure that it isn't already the session leader */
	  pid = fork();
	  if (pid &lt; 0) {
		  perror("fork");
		  return 1;
	  }

	  if (pid &gt; 0) {
		  /* top parent, wait for everyone */
		  while (waitpid(-1, NULL, 0) &gt;= 0)
			  ;
		  if (errno != ECHILD)
			  perror("waitpid");
		  return 0;
	  }

	  /* new session, start a new session and set the controlling tty */
	  if (setsid() &lt; 0) {
		  perror("setsid");
		  return 1;
	  }

	  fd = open(argv[1], O_RDWR);
	  if (fd &lt; 0) {
		  perror("open");
		  return 1;
	  }

	  if (ioctl(fd, TIOCSCTTY, 1) &lt; 0) {
		  perror("ioctl");
		  return 1;
	  }

	  /* fork a child, sleep a bit and exit */
	  pid = fork();
	  if (pid &lt; 0) {
		  perror("fork");
		  return 1;
	  }

	  if (pid &gt; 0) {
		  nanosleep(&amp;ts1s, NULL);
		  printf("Session leader exiting\n");
		  exit(0);
	  }

	  /*
	   * The child ignores SIGHUP and keeps reading from the controlling
	   * tty.  Because SIGHUP is ignored, the child doesn't get killed on
	   * parent exit and the bug in n_tty makes the read(2) block the
	   * parent's control terminal hangup attempt.  The parent ends up in
	   * D sleep until the child is explicitly killed.
	   */
	  sigaction(SIGHUP, &amp;sact, NULL);
	  printf("Child reading tty\n");
	  while (1) {
		  char buf[1024];

		  if (read(fd, buf, sizeof(buf)) &lt; 0) {
			  perror("read");
			  return 1;
		  }
	  }

	  return 0;
  }

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Alan Cox &lt;alan@llwyncelyn.cymru&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 28b0f8a6962a24ed21737578f3b1b07424635c9e ]

A tty is hung up by __tty_hangup() setting file-&gt;f_op to
hung_up_tty_fops, which is skipped on ttys whose write operation isn't
tty_write().  This means that, for example, /dev/console whose write
op is redirected_tty_write() is never actually marked hung up.

Because n_tty_read() uses the hung up status to decide whether to
abort the waiting readers, the lack of hung-up marking can lead to the
following scenario.

 1. A session contains two processes.  The leader and its child.  The
    child ignores SIGHUP.

 2. The leader exits and starts disassociating from the controlling
    terminal (/dev/console).

 3. __tty_hangup() skips setting f_op to hung_up_tty_fops.

 4. SIGHUP is delivered and ignored.

 5. tty_ldisc_hangup() is invoked.  It wakes up the waits which should
    clear the read lockers of tty-&gt;ldisc_sem.

 6. The reader wakes up but because tty_hung_up_p() is false, it
    doesn't abort and goes back to sleep while read-holding
    tty-&gt;ldisc_sem.

 7. The leader progresses to tty_ldisc_lock() in tty_ldisc_hangup()
    and is now stuck in D sleep indefinitely waiting for
    tty-&gt;ldisc_sem.

The following is Alan's explanation on why some ttys aren't hung up.

 http://lkml.kernel.org/r/20171101170908.6ad08580@alans-desktop

 1. It broke the serial consoles because they would hang up and close
    down the hardware. With tty_port that *should* be fixable properly
    for any cases remaining.

 2. The console layer was (and still is) completely broken and doens't
    refcount properly. So if you turn on console hangups it breaks (as
    indeed does freeing consoles and half a dozen other things).

As neither can be fixed quickly, this patch works around the problem
by introducing a new flag, TTY_HUPPING, which is used solely to tell
n_tty_read() that hang-up is in progress for the console and the
readers should be aborted regardless of the hung-up status of the
device.

The following is a sample hung task warning caused by this issue.

  INFO: task agetty:2662 blocked for more than 120 seconds.
        Not tainted 4.11.3-dbg-tty-lockup-02478-gfd6c7ee-dirty #28
  "echo 0 &gt; /proc/sys/kernel/hung_task_timeout_secs" disables this message.
      0  2662      1 0x00000086
  Call Trace:
   __schedule+0x267/0x890
   schedule+0x36/0x80
   schedule_timeout+0x23c/0x2e0
   ldsem_down_write+0xce/0x1f6
   tty_ldisc_lock+0x16/0x30
   tty_ldisc_hangup+0xb3/0x1b0
   __tty_hangup+0x300/0x410
   disassociate_ctty+0x6c/0x290
   do_exit+0x7ef/0xb00
   do_group_exit+0x3f/0xa0
   get_signal+0x1b3/0x5d0
   do_signal+0x28/0x660
   exit_to_usermode_loop+0x46/0x86
   do_syscall_64+0x9c/0xb0
   entry_SYSCALL64_slow_path+0x25/0x25

The following is the repro.  Run "$PROG /dev/console".  The parent
process hangs in D state.

  #include &lt;sys/types.h&gt;
  #include &lt;sys/stat.h&gt;
  #include &lt;sys/wait.h&gt;
  #include &lt;sys/ioctl.h&gt;
  #include &lt;fcntl.h&gt;
  #include &lt;unistd.h&gt;
  #include &lt;stdio.h&gt;
  #include &lt;stdlib.h&gt;
  #include &lt;errno.h&gt;
  #include &lt;signal.h&gt;
  #include &lt;time.h&gt;
  #include &lt;termios.h&gt;

  int main(int argc, char **argv)
  {
	  struct sigaction sact = { .sa_handler = SIG_IGN };
	  struct timespec ts1s = { .tv_sec = 1 };
	  pid_t pid;
	  int fd;

	  if (argc &lt; 2) {
		  fprintf(stderr, "test-hung-tty /dev/$TTY\n");
		  return 1;
	  }

	  /* fork a child to ensure that it isn't already the session leader */
	  pid = fork();
	  if (pid &lt; 0) {
		  perror("fork");
		  return 1;
	  }

	  if (pid &gt; 0) {
		  /* top parent, wait for everyone */
		  while (waitpid(-1, NULL, 0) &gt;= 0)
			  ;
		  if (errno != ECHILD)
			  perror("waitpid");
		  return 0;
	  }

	  /* new session, start a new session and set the controlling tty */
	  if (setsid() &lt; 0) {
		  perror("setsid");
		  return 1;
	  }

	  fd = open(argv[1], O_RDWR);
	  if (fd &lt; 0) {
		  perror("open");
		  return 1;
	  }

	  if (ioctl(fd, TIOCSCTTY, 1) &lt; 0) {
		  perror("ioctl");
		  return 1;
	  }

	  /* fork a child, sleep a bit and exit */
	  pid = fork();
	  if (pid &lt; 0) {
		  perror("fork");
		  return 1;
	  }

	  if (pid &gt; 0) {
		  nanosleep(&amp;ts1s, NULL);
		  printf("Session leader exiting\n");
		  exit(0);
	  }

	  /*
	   * The child ignores SIGHUP and keeps reading from the controlling
	   * tty.  Because SIGHUP is ignored, the child doesn't get killed on
	   * parent exit and the bug in n_tty makes the read(2) block the
	   * parent's control terminal hangup attempt.  The parent ends up in
	   * D sleep until the child is explicitly killed.
	   */
	  sigaction(SIGHUP, &amp;sact, NULL);
	  printf("Child reading tty\n");
	  while (1) {
		  char buf[1024];

		  if (read(fd, buf, sizeof(buf)) &lt; 0) {
			  perror("read");
			  return 1;
		  }
	  }

	  return 0;
  }

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Alan Cox &lt;alan@llwyncelyn.cymru&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Kbuild: provide a __UNIQUE_ID for clang</title>
<updated>2018-05-23T01:36:30+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2016-02-08T14:38:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9fd0d2d5b61ca06e093dab355813c3ded2252f31'/>
<id>9fd0d2d5b61ca06e093dab355813c3ded2252f31</id>
<content type='text'>
[ Upstream commit b41c29b0527c7fd6a95d0f71274abb79933bf960 ]

The default __UNIQUE_ID macro in compiler.h fails to work for some drivers:

drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c:615:1: error: redefinition of
      '__UNIQUE_ID_firmware615'
BRCMF_FW_NVRAM_DEF(4354, "brcmfmac4354-sdio.bin", "brcmfmac4354-sdio.txt");

This adds a copy of the version we use for gcc-4.3 and higher, as the same
one works with all versions of clang that I could find in svn (2.6 and higher).

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Michal Marek &lt;mmarek@suse.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b41c29b0527c7fd6a95d0f71274abb79933bf960 ]

The default __UNIQUE_ID macro in compiler.h fails to work for some drivers:

drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c:615:1: error: redefinition of
      '__UNIQUE_ID_firmware615'
BRCMF_FW_NVRAM_DEF(4354, "brcmfmac4354-sdio.bin", "brcmfmac4354-sdio.txt");

This adds a copy of the version we use for gcc-4.3 and higher, as the same
one works with all versions of clang that I could find in svn (2.6 and higher).

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Michal Marek &lt;mmarek@suse.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/mlx4: Fix the check in attaching steering rules</title>
<updated>2018-05-23T01:36:27+00:00</updated>
<author>
<name>Talat Batheesh</name>
<email>talatb@mellanox.com</email>
</author>
<published>2017-06-04T11:30:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=63e5ecca42f1162dc0832be0b8c95b9a181e89a0'/>
<id>63e5ecca42f1162dc0832be0b8c95b9a181e89a0</id>
<content type='text'>
[ Upstream commit 6dc06c08bef1c746ff8da33dab677cfbacdcad32 ]

Our previous patch (cited below) introduced a regression
for RAW Eth QPs.

Fix it by checking if the QP number provided by user-space
exists, hence allowing steering rules to be added for valid
QPs only.

Fixes: 89c557687a32 ("net/mlx4_en: Avoid adding steering rules with invalid ring")
Reported-by: Or Gerlitz &lt;gerlitz.or@gmail.com&gt;
Signed-off-by: Talat Batheesh &lt;talatb@mellanox.com&gt;
Signed-off-by: Tariq Toukan &lt;tariqt@mellanox.com&gt;
Acked-by: Or Gerlitz &lt;ogerlitz@mellanox.com&gt;
Reviewed-by: Leon Romanovsky &lt;leonro@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6dc06c08bef1c746ff8da33dab677cfbacdcad32 ]

Our previous patch (cited below) introduced a regression
for RAW Eth QPs.

Fix it by checking if the QP number provided by user-space
exists, hence allowing steering rules to be added for valid
QPs only.

Fixes: 89c557687a32 ("net/mlx4_en: Avoid adding steering rules with invalid ring")
Reported-by: Or Gerlitz &lt;gerlitz.or@gmail.com&gt;
Signed-off-by: Talat Batheesh &lt;talatb@mellanox.com&gt;
Signed-off-by: Tariq Toukan &lt;tariqt@mellanox.com&gt;
Acked-by: Or Gerlitz &lt;ogerlitz@mellanox.com&gt;
Reviewed-by: Leon Romanovsky &lt;leonro@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>skbuff: return -EMSGSIZE in skb_to_sgvec to prevent overflow</title>
<updated>2018-05-23T01:36:27+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2017-06-04T02:16:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=de85297ffe4c7ec2ae917a0a2065e2bd9b485781'/>
<id>de85297ffe4c7ec2ae917a0a2065e2bd9b485781</id>
<content type='text'>
[ Upstream commit 48a1df65334b74bd7531f932cca5928932abf769 ]

This is a defense-in-depth measure in response to bugs like
4d6fa57b4dab ("macsec: avoid heap overflow in skb_to_sgvec"). There's
not only a potential overflow of sglist items, but also a stack overflow
potential, so we fix this by limiting the amount of recursion this function
is allowed to do. Not actually providing a bounded base case is a future
disaster that we can easily avoid here.

As a small matter of house keeping, we take this opportunity to move the
documentation comment over the actual function the documentation is for.

While this could be implemented by using an explicit stack of skbuffs,
when implementing this, the function complexity increased considerably,
and I don't think such complexity and bloat is actually worth it. So,
instead I built this and tested it on x86, x86_64, ARM, ARM64, and MIPS,
and measured the stack usage there. I also reverted the recent MIPS
changes that give it a separate IRQ stack, so that I could experience
some worst-case situations. I found that limiting it to 24 layers deep
yielded a good stack usage with room for safety, as well as being much
deeper than any driver actually ever creates.

Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Cc: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Sabrina Dubroca &lt;sd@queasysnail.net&gt;
Cc: "Michael S. Tsirkin" &lt;mst@redhat.com&gt;
Cc: Jason Wang &lt;jasowang@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 48a1df65334b74bd7531f932cca5928932abf769 ]

This is a defense-in-depth measure in response to bugs like
4d6fa57b4dab ("macsec: avoid heap overflow in skb_to_sgvec"). There's
not only a potential overflow of sglist items, but also a stack overflow
potential, so we fix this by limiting the amount of recursion this function
is allowed to do. Not actually providing a bounded base case is a future
disaster that we can easily avoid here.

As a small matter of house keeping, we take this opportunity to move the
documentation comment over the actual function the documentation is for.

While this could be implemented by using an explicit stack of skbuffs,
when implementing this, the function complexity increased considerably,
and I don't think such complexity and bloat is actually worth it. So,
instead I built this and tested it on x86, x86_64, ARM, ARM64, and MIPS,
and measured the stack usage there. I also reverted the recent MIPS
changes that give it a separate IRQ stack, so that I could experience
some worst-case situations. I found that limiting it to 24 layers deep
yielded a good stack usage with room for safety, as well as being much
deeper than any driver actually ever creates.

Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Cc: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Sabrina Dubroca &lt;sd@queasysnail.net&gt;
Cc: "Michael S. Tsirkin" &lt;mst@redhat.com&gt;
Cc: Jason Wang &lt;jasowang@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>llist: clang: introduce member_address_is_nonnull()</title>
<updated>2018-05-23T01:33:57+00:00</updated>
<author>
<name>Alexander Potapenko</name>
<email>glider@google.com</email>
</author>
<published>2017-07-19T18:27:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=de7d849418ce67c65bcefdaf6f1c8a257962208a'/>
<id>de7d849418ce67c65bcefdaf6f1c8a257962208a</id>
<content type='text'>
[ Upstream commit beaec533fc2701a28a4d667f67c9f59c6e4e0d13 ]

Currently llist_for_each_entry() and llist_for_each_entry_safe() iterate
until &amp;pos-&gt;member != NULL.  But when building the kernel with Clang,
the compiler assumes &amp;pos-&gt;member cannot be NULL if the member's offset
is greater than 0 (which would be equivalent to the object being
non-contiguous in memory).  Therefore the loop condition is always true,
and the loops become infinite.

To work around this, introduce the member_address_is_nonnull() macro,
which casts object pointer to uintptr_t, thus letting the member pointer
to be NULL.

Signed-off-by: Alexander Potapenko &lt;glider@google.com&gt;
Tested-by: Sodagudi Prasad &lt;psodagud@codeaurora.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit beaec533fc2701a28a4d667f67c9f59c6e4e0d13 ]

Currently llist_for_each_entry() and llist_for_each_entry_safe() iterate
until &amp;pos-&gt;member != NULL.  But when building the kernel with Clang,
the compiler assumes &amp;pos-&gt;member cannot be NULL if the member's offset
is greater than 0 (which would be equivalent to the object being
non-contiguous in memory).  Therefore the loop condition is always true,
and the loops become infinite.

To work around this, introduce the member_address_is_nonnull() macro,
which casts object pointer to uintptr_t, thus letting the member pointer
to be NULL.

Signed-off-by: Alexander Potapenko &lt;glider@google.com&gt;
Tested-by: Sodagudi Prasad &lt;psodagud@codeaurora.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
