<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net/ax25, branch v4.19.145</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>AX.25: Prevent integer overflows in connect and sendmsg</title>
<updated>2020-07-31T16:37:48+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2020-07-23T14:49:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f0965dc9e6b5a3e215c69c9c554081d108ff1aa2'/>
<id>f0965dc9e6b5a3e215c69c9c554081d108ff1aa2</id>
<content type='text'>
[ Upstream commit 17ad73e941b71f3bec7523ea4e9cbc3752461c2d ]

We recently added some bounds checking in ax25_connect() and
ax25_sendmsg() and we so we removed the AX25_MAX_DIGIS checks because
they were no longer required.

Unfortunately, I believe they are required to prevent integer overflows
so I have added them back.

Fixes: 8885bb0621f0 ("AX.25: Prevent out-of-bounds read in ax25_sendmsg()")
Fixes: 2f2a7ffad5c6 ("AX.25: Fix out-of-bounds read in ax25_connect()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 17ad73e941b71f3bec7523ea4e9cbc3752461c2d ]

We recently added some bounds checking in ax25_connect() and
ax25_sendmsg() and we so we removed the AX25_MAX_DIGIS checks because
they were no longer required.

Unfortunately, I believe they are required to prevent integer overflows
so I have added them back.

Fixes: 8885bb0621f0 ("AX.25: Prevent out-of-bounds read in ax25_sendmsg()")
Fixes: 2f2a7ffad5c6 ("AX.25: Fix out-of-bounds read in ax25_connect()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>AX.25: Prevent out-of-bounds read in ax25_sendmsg()</title>
<updated>2020-07-31T16:37:47+00:00</updated>
<author>
<name>Peilin Ye</name>
<email>yepeilin.cs@gmail.com</email>
</author>
<published>2020-07-22T16:05:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=4d9bd02c9e76118d36aec820a4e8b8d295980859'/>
<id>4d9bd02c9e76118d36aec820a4e8b8d295980859</id>
<content type='text'>
[ Upstream commit 8885bb0621f01a6c82be60a91e5fc0f6e2f71186 ]

Checks on `addr_len` and `usax-&gt;sax25_ndigis` are insufficient.
ax25_sendmsg() can go out of bounds when `usax-&gt;sax25_ndigis` equals to 7
or 8. Fix it.

It is safe to remove `usax-&gt;sax25_ndigis &gt; AX25_MAX_DIGIS`, since
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`

Signed-off-by: Peilin Ye &lt;yepeilin.cs@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8885bb0621f01a6c82be60a91e5fc0f6e2f71186 ]

Checks on `addr_len` and `usax-&gt;sax25_ndigis` are insufficient.
ax25_sendmsg() can go out of bounds when `usax-&gt;sax25_ndigis` equals to 7
or 8. Fix it.

It is safe to remove `usax-&gt;sax25_ndigis &gt; AX25_MAX_DIGIS`, since
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`

Signed-off-by: Peilin Ye &lt;yepeilin.cs@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>AX.25: Fix out-of-bounds read in ax25_connect()</title>
<updated>2020-07-31T16:37:47+00:00</updated>
<author>
<name>Peilin Ye</name>
<email>yepeilin.cs@gmail.com</email>
</author>
<published>2020-07-22T15:19:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=0724acc5660c6976c53216a5dd7a062ce15a11da'/>
<id>0724acc5660c6976c53216a5dd7a062ce15a11da</id>
<content type='text'>
[ Upstream commit 2f2a7ffad5c6cbf3d438e813cfdc88230e185ba6 ]

Checks on `addr_len` and `fsa-&gt;fsa_ax25.sax25_ndigis` are insufficient.
ax25_connect() can go out of bounds when `fsa-&gt;fsa_ax25.sax25_ndigis`
equals to 7 or 8. Fix it.

This issue has been reported as a KMSAN uninit-value bug, because in such
a case, ax25_connect() reaches into the uninitialized portion of the
`struct sockaddr_storage` statically allocated in __sys_connect().

It is safe to remove `fsa-&gt;fsa_ax25.sax25_ndigis &gt; AX25_MAX_DIGIS` because
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`.

Reported-by: syzbot+c82752228ed975b0a623@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=55ef9d629f3b3d7d70b69558015b63b48d01af66
Signed-off-by: Peilin Ye &lt;yepeilin.cs@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2f2a7ffad5c6cbf3d438e813cfdc88230e185ba6 ]

Checks on `addr_len` and `fsa-&gt;fsa_ax25.sax25_ndigis` are insufficient.
ax25_connect() can go out of bounds when `fsa-&gt;fsa_ax25.sax25_ndigis`
equals to 7 or 8. Fix it.

This issue has been reported as a KMSAN uninit-value bug, because in such
a case, ax25_connect() reaches into the uninitialized portion of the
`struct sockaddr_storage` statically allocated in __sys_connect().

It is safe to remove `fsa-&gt;fsa_ax25.sax25_ndigis &gt; AX25_MAX_DIGIS` because
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`.

Reported-by: syzbot+c82752228ed975b0a623@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=55ef9d629f3b3d7d70b69558015b63b48d01af66
Signed-off-by: Peilin Ye &lt;yepeilin.cs@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ax25: fix setsockopt(SO_BINDTODEVICE)</title>
<updated>2020-06-03T06:19:02+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2020-05-20T01:24:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=efdf6e3c7860139fb79a47b8ef0596b9a58540bd'/>
<id>efdf6e3c7860139fb79a47b8ef0596b9a58540bd</id>
<content type='text'>
[ Upstream commit 687775cec056b38a4c8f3291e0dd7a9145f7b667 ]

syzbot was able to trigger this trace [1], probably by using
a zero optlen.

While we are at it, cap optlen to IFNAMSIZ - 1 instead of IFNAMSIZ.

[1]
BUG: KMSAN: uninit-value in strnlen+0xf9/0x170 lib/string.c:569
CPU: 0 PID: 8807 Comm: syz-executor483 Not tainted 5.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 strnlen+0xf9/0x170 lib/string.c:569
 dev_name_hash net/core/dev.c:207 [inline]
 netdev_name_node_lookup net/core/dev.c:277 [inline]
 __dev_get_by_name+0x75/0x2b0 net/core/dev.c:778
 ax25_setsockopt+0xfa3/0x1170 net/ax25/af_ax25.c:654
 __compat_sys_setsockopt+0x4ed/0x910 net/compat.c:403
 __do_compat_sys_setsockopt net/compat.c:413 [inline]
 __se_compat_sys_setsockopt+0xdd/0x100 net/compat.c:410
 __ia32_compat_sys_setsockopt+0x62/0x80 net/compat.c:410
 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline]
 do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398
 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f57dd9
Code: 90 e8 0b 00 00 00 f3 90 0f ae e8 eb f9 8d 74 26 00 89 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 &lt;5d&gt; 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000ffae8c1c EFLAGS: 00000217 ORIG_RAX: 000000000000016e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000101
RDX: 0000000000000019 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 0000000000000012 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Local variable ----devname@ax25_setsockopt created at:
 ax25_setsockopt+0xe6/0x1170 net/ax25/af_ax25.c:536
 ax25_setsockopt+0xe6/0x1170 net/ax25/af_ax25.c:536

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 687775cec056b38a4c8f3291e0dd7a9145f7b667 ]

syzbot was able to trigger this trace [1], probably by using
a zero optlen.

While we are at it, cap optlen to IFNAMSIZ - 1 instead of IFNAMSIZ.

[1]
BUG: KMSAN: uninit-value in strnlen+0xf9/0x170 lib/string.c:569
CPU: 0 PID: 8807 Comm: syz-executor483 Not tainted 5.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 strnlen+0xf9/0x170 lib/string.c:569
 dev_name_hash net/core/dev.c:207 [inline]
 netdev_name_node_lookup net/core/dev.c:277 [inline]
 __dev_get_by_name+0x75/0x2b0 net/core/dev.c:778
 ax25_setsockopt+0xfa3/0x1170 net/ax25/af_ax25.c:654
 __compat_sys_setsockopt+0x4ed/0x910 net/compat.c:403
 __do_compat_sys_setsockopt net/compat.c:413 [inline]
 __se_compat_sys_setsockopt+0xdd/0x100 net/compat.c:410
 __ia32_compat_sys_setsockopt+0x62/0x80 net/compat.c:410
 do_syscall_32_irqs_on arch/x86/entry/common.c:339 [inline]
 do_fast_syscall_32+0x3bf/0x6d0 arch/x86/entry/common.c:398
 entry_SYSENTER_compat+0x68/0x77 arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f57dd9
Code: 90 e8 0b 00 00 00 f3 90 0f ae e8 eb f9 8d 74 26 00 89 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 &lt;5d&gt; 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000ffae8c1c EFLAGS: 00000217 ORIG_RAX: 000000000000016e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000101
RDX: 0000000000000019 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 0000000000000012 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Local variable ----devname@ax25_setsockopt created at:
 ax25_setsockopt+0xe6/0x1170 net/ax25/af_ax25.c:536
 ax25_setsockopt+0xe6/0x1170 net/ax25/af_ax25.c:536

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ax25: enforce CAP_NET_RAW for raw sockets</title>
<updated>2019-10-05T11:09:32+00:00</updated>
<author>
<name>Ori Nimron</name>
<email>orinimron123@gmail.com</email>
</author>
<published>2019-09-20T07:35:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6f0f18e532693ecc1e0c7938e0d63531ea62bc3e'/>
<id>6f0f18e532693ecc1e0c7938e0d63531ea62bc3e</id>
<content type='text'>
[ Upstream commit 0614e2b73768b502fc32a75349823356d98aae2c ]

When creating a raw AF_AX25 socket, CAP_NET_RAW needs to be checked
first.

Signed-off-by: Ori Nimron &lt;orinimron123@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0614e2b73768b502fc32a75349823356d98aae2c ]

When creating a raw AF_AX25 socket, CAP_NET_RAW needs to be checked
first.

Signed-off-by: Ori Nimron &lt;orinimron123@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ax25: fix inconsistent lock state in ax25_destroy_timer</title>
<updated>2019-06-22T06:15:13+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2019-06-15T23:40:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=10faaa359b41797ef86373ca6028b2c9049686b9'/>
<id>10faaa359b41797ef86373ca6028b2c9049686b9</id>
<content type='text'>
[ Upstream commit d4d5d8e83c9616aeef28a2869cea49cc3fb35526 ]

Before thread in process context uses bh_lock_sock()
we must disable bh.

sysbot reported :

WARNING: inconsistent lock state
5.2.0-rc3+ #32 Not tainted

inconsistent {SOFTIRQ-ON-W} -&gt; {IN-SOFTIRQ-W} usage.
blkid/26581 [HC0[0]:SC1[1]:HE1:SE0] takes:
00000000e0da85ee (slock-AF_AX25){+.?.}, at: spin_lock include/linux/spinlock.h:338 [inline]
00000000e0da85ee (slock-AF_AX25){+.?.}, at: ax25_destroy_timer+0x53/0xc0 net/ax25/af_ax25.c:275
{SOFTIRQ-ON-W} state was registered at:
  lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
  spin_lock include/linux/spinlock.h:338 [inline]
  ax25_rt_autobind+0x3ca/0x720 net/ax25/ax25_route.c:429
  ax25_connect.cold+0x30/0xa4 net/ax25/af_ax25.c:1221
  __sys_connect+0x264/0x330 net/socket.c:1834
  __do_sys_connect net/socket.c:1845 [inline]
  __se_sys_connect net/socket.c:1842 [inline]
  __x64_sys_connect+0x73/0xb0 net/socket.c:1842
  do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
irq event stamp: 2272
hardirqs last  enabled at (2272): [&lt;ffffffff810065f3&gt;] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (2271): [&lt;ffffffff8100660f&gt;] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (1522): [&lt;ffffffff87400654&gt;] __do_softirq+0x654/0x94c kernel/softirq.c:320
softirqs last disabled at (2267): [&lt;ffffffff81449010&gt;] invoke_softirq kernel/softirq.c:374 [inline]
softirqs last disabled at (2267): [&lt;ffffffff81449010&gt;] irq_exit+0x180/0x1d0 kernel/softirq.c:414

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(slock-AF_AX25);
  &lt;Interrupt&gt;
    lock(slock-AF_AX25);

 *** DEADLOCK ***

1 lock held by blkid/26581:
 #0: 0000000010fd154d ((&amp;ax25-&gt;dtimer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:175 [inline]
 #0: 0000000010fd154d ((&amp;ax25-&gt;dtimer)){+.-.}, at: call_timer_fn+0xe0/0x720 kernel/time/timer.c:1312

stack backtrace:
CPU: 1 PID: 26581 Comm: blkid Not tainted 5.2.0-rc3+ #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 &lt;IRQ&gt;
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_usage_bug.cold+0x393/0x4a2 kernel/locking/lockdep.c:2935
 valid_state kernel/locking/lockdep.c:2948 [inline]
 mark_lock_irq kernel/locking/lockdep.c:3138 [inline]
 mark_lock+0xd46/0x1370 kernel/locking/lockdep.c:3513
 mark_irqflags kernel/locking/lockdep.c:3391 [inline]
 __lock_acquire+0x159f/0x5490 kernel/locking/lockdep.c:3745
 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:338 [inline]
 ax25_destroy_timer+0x53/0xc0 net/ax25/af_ax25.c:275
 call_timer_fn+0x193/0x720 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers kernel/time/timer.c:1685 [inline]
 __run_timers kernel/time/timer.c:1653 [inline]
 run_timer_softirq+0x66f/0x1740 kernel/time/timer.c:1698
 __do_softirq+0x25c/0x94c kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:414
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x13b/0x550 arch/x86/kernel/apic/apic.c:1068
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
 &lt;/IRQ&gt;
RIP: 0033:0x7f858d5c3232
Code: 8b 61 08 48 8b 84 24 d8 00 00 00 4c 89 44 24 28 48 8b ac 24 d0 00 00 00 4c 8b b4 24 e8 00 00 00 48 89 7c 24 68 48 89 4c 24 78 &lt;48&gt; 89 44 24 58 8b 84 24 e0 00 00 00 89 84 24 84 00 00 00 8b 84 24
RSP: 002b:00007ffcaf0cf5c0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 00007f858d7d27a8 RBX: 00007f858d7d8820 RCX: 00007f858d3940d8
RDX: 00007ffcaf0cf798 RSI: 00000000f5e616f3 RDI: 00007f858d394fee
RBP: 0000000000000000 R08: 00007ffcaf0cf780 R09: 00007f858d7db480
R10: 0000000000000000 R11: 0000000009691a75 R12: 0000000000000005
R13: 00000000f5e616f3 R14: 0000000000000000 R15: 00007ffcaf0cf798

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d4d5d8e83c9616aeef28a2869cea49cc3fb35526 ]

Before thread in process context uses bh_lock_sock()
we must disable bh.

sysbot reported :

WARNING: inconsistent lock state
5.2.0-rc3+ #32 Not tainted

inconsistent {SOFTIRQ-ON-W} -&gt; {IN-SOFTIRQ-W} usage.
blkid/26581 [HC0[0]:SC1[1]:HE1:SE0] takes:
00000000e0da85ee (slock-AF_AX25){+.?.}, at: spin_lock include/linux/spinlock.h:338 [inline]
00000000e0da85ee (slock-AF_AX25){+.?.}, at: ax25_destroy_timer+0x53/0xc0 net/ax25/af_ax25.c:275
{SOFTIRQ-ON-W} state was registered at:
  lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
  spin_lock include/linux/spinlock.h:338 [inline]
  ax25_rt_autobind+0x3ca/0x720 net/ax25/ax25_route.c:429
  ax25_connect.cold+0x30/0xa4 net/ax25/af_ax25.c:1221
  __sys_connect+0x264/0x330 net/socket.c:1834
  __do_sys_connect net/socket.c:1845 [inline]
  __se_sys_connect net/socket.c:1842 [inline]
  __x64_sys_connect+0x73/0xb0 net/socket.c:1842
  do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
irq event stamp: 2272
hardirqs last  enabled at (2272): [&lt;ffffffff810065f3&gt;] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (2271): [&lt;ffffffff8100660f&gt;] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (1522): [&lt;ffffffff87400654&gt;] __do_softirq+0x654/0x94c kernel/softirq.c:320
softirqs last disabled at (2267): [&lt;ffffffff81449010&gt;] invoke_softirq kernel/softirq.c:374 [inline]
softirqs last disabled at (2267): [&lt;ffffffff81449010&gt;] irq_exit+0x180/0x1d0 kernel/softirq.c:414

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(slock-AF_AX25);
  &lt;Interrupt&gt;
    lock(slock-AF_AX25);

 *** DEADLOCK ***

1 lock held by blkid/26581:
 #0: 0000000010fd154d ((&amp;ax25-&gt;dtimer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:175 [inline]
 #0: 0000000010fd154d ((&amp;ax25-&gt;dtimer)){+.-.}, at: call_timer_fn+0xe0/0x720 kernel/time/timer.c:1312

stack backtrace:
CPU: 1 PID: 26581 Comm: blkid Not tainted 5.2.0-rc3+ #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 &lt;IRQ&gt;
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_usage_bug.cold+0x393/0x4a2 kernel/locking/lockdep.c:2935
 valid_state kernel/locking/lockdep.c:2948 [inline]
 mark_lock_irq kernel/locking/lockdep.c:3138 [inline]
 mark_lock+0xd46/0x1370 kernel/locking/lockdep.c:3513
 mark_irqflags kernel/locking/lockdep.c:3391 [inline]
 __lock_acquire+0x159f/0x5490 kernel/locking/lockdep.c:3745
 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:338 [inline]
 ax25_destroy_timer+0x53/0xc0 net/ax25/af_ax25.c:275
 call_timer_fn+0x193/0x720 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers kernel/time/timer.c:1685 [inline]
 __run_timers kernel/time/timer.c:1653 [inline]
 run_timer_softirq+0x66f/0x1740 kernel/time/timer.c:1698
 __do_softirq+0x25c/0x94c kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:414
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x13b/0x550 arch/x86/kernel/apic/apic.c:1068
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
 &lt;/IRQ&gt;
RIP: 0033:0x7f858d5c3232
Code: 8b 61 08 48 8b 84 24 d8 00 00 00 4c 89 44 24 28 48 8b ac 24 d0 00 00 00 4c 8b b4 24 e8 00 00 00 48 89 7c 24 68 48 89 4c 24 78 &lt;48&gt; 89 44 24 58 8b 84 24 e0 00 00 00 89 84 24 84 00 00 00 8b 84 24
RSP: 002b:00007ffcaf0cf5c0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 00007f858d7d27a8 RBX: 00007f858d7d8820 RCX: 00007f858d3940d8
RDX: 00007ffcaf0cf798 RSI: 00000000f5e616f3 RDI: 00007f858d394fee
RBP: 0000000000000000 R08: 00007ffcaf0cf780 R09: 00007f858d7db480
R10: 0000000000000000 R11: 0000000009691a75 R12: 0000000000000005
R13: 00000000f5e616f3 R14: 0000000000000000 R15: 00007ffcaf0cf798

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ax25: fix possible use-after-free</title>
<updated>2019-02-23T08:07:27+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2019-01-22T18:40:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=eed11c69d275790ac83b8adaf54b7cbef5d316a5'/>
<id>eed11c69d275790ac83b8adaf54b7cbef5d316a5</id>
<content type='text'>
commit 63530aba7826a0f8e129874df9c4d264f9db3f9e upstream.

syzbot found that ax25 routes where not properly protected
against concurrent use [1].

In this particular report the bug happened while
copying ax25-&gt;digipeat.

Fix this problem by making sure we call ax25_get_route()
while ax25_route_lock is held, so that no modification
could happen while using the route.

The current two ax25_get_route() callers do not sleep,
so this change should be fine.

Once we do that, ax25_get_route() no longer needs to
grab a reference on the found route.

[1]
ax25_connect(): syz-executor0 uses autobind, please contact jreuter@yaina.de
BUG: KASAN: use-after-free in memcpy include/linux/string.h:352 [inline]
BUG: KASAN: use-after-free in kmemdup+0x42/0x60 mm/util.c:113
Read of size 66 at addr ffff888066641a80 by task syz-executor2/531

ax25_connect(): syz-executor0 uses autobind, please contact jreuter@yaina.de
CPU: 1 PID: 531 Comm: syz-executor2 Not tainted 5.0.0-rc2+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 memcpy+0x24/0x50 mm/kasan/common.c:130
 memcpy include/linux/string.h:352 [inline]
 kmemdup+0x42/0x60 mm/util.c:113
 kmemdup include/linux/string.h:425 [inline]
 ax25_rt_autobind+0x25d/0x750 net/ax25/ax25_route.c:424
 ax25_connect.cold+0x30/0xa4 net/ax25/af_ax25.c:1224
 __sys_connect+0x357/0x490 net/socket.c:1664
 __do_sys_connect net/socket.c:1675 [inline]
 __se_sys_connect net/socket.c:1672 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1672
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458099
Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f870ee22c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458099
RDX: 0000000000000048 RSI: 0000000020000080 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
ax25_connect(): syz-executor4 uses autobind, please contact jreuter@yaina.de
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f870ee236d4
R13: 00000000004be48e R14: 00000000004ce9a8 R15: 00000000ffffffff

Allocated by task 526:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
ax25_connect(): syz-executor5 uses autobind, please contact jreuter@yaina.de
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3609
 kmalloc include/linux/slab.h:545 [inline]
 ax25_rt_add net/ax25/ax25_route.c:95 [inline]
 ax25_rt_ioctl+0x3b9/0x1270 net/ax25/ax25_route.c:233
 ax25_ioctl+0x322/0x10b0 net/ax25/af_ax25.c:1763
 sock_do_ioctl+0xe2/0x400 net/socket.c:950
 sock_ioctl+0x32f/0x6c0 net/socket.c:1074
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

ax25_connect(): syz-executor5 uses autobind, please contact jreuter@yaina.de
Freed by task 550:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466
 __cache_free mm/slab.c:3487 [inline]
 kfree+0xcf/0x230 mm/slab.c:3806
 ax25_rt_add net/ax25/ax25_route.c:92 [inline]
 ax25_rt_ioctl+0x304/0x1270 net/ax25/ax25_route.c:233
 ax25_ioctl+0x322/0x10b0 net/ax25/af_ax25.c:1763
 sock_do_ioctl+0xe2/0x400 net/socket.c:950
 sock_ioctl+0x32f/0x6c0 net/socket.c:1074
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888066641a80
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 0 bytes inside of
 96-byte region [ffff888066641a80, ffff888066641ae0)
The buggy address belongs to the page:
page:ffffea0001999040 count:1 mapcount:0 mapping:ffff88812c3f04c0 index:0x0
flags: 0x1fffc0000000200(slab)
ax25_connect(): syz-executor4 uses autobind, please contact jreuter@yaina.de
raw: 01fffc0000000200 ffffea0001817948 ffffea0002341dc8 ffff88812c3f04c0
raw: 0000000000000000 ffff888066641000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888066641980: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888066641a00: 00 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc
&gt;ffff888066641a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                   ^
 ffff888066641b00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888066641b80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 63530aba7826a0f8e129874df9c4d264f9db3f9e upstream.

syzbot found that ax25 routes where not properly protected
against concurrent use [1].

In this particular report the bug happened while
copying ax25-&gt;digipeat.

Fix this problem by making sure we call ax25_get_route()
while ax25_route_lock is held, so that no modification
could happen while using the route.

The current two ax25_get_route() callers do not sleep,
so this change should be fine.

Once we do that, ax25_get_route() no longer needs to
grab a reference on the found route.

[1]
ax25_connect(): syz-executor0 uses autobind, please contact jreuter@yaina.de
BUG: KASAN: use-after-free in memcpy include/linux/string.h:352 [inline]
BUG: KASAN: use-after-free in kmemdup+0x42/0x60 mm/util.c:113
Read of size 66 at addr ffff888066641a80 by task syz-executor2/531

ax25_connect(): syz-executor0 uses autobind, please contact jreuter@yaina.de
CPU: 1 PID: 531 Comm: syz-executor2 Not tainted 5.0.0-rc2+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 memcpy+0x24/0x50 mm/kasan/common.c:130
 memcpy include/linux/string.h:352 [inline]
 kmemdup+0x42/0x60 mm/util.c:113
 kmemdup include/linux/string.h:425 [inline]
 ax25_rt_autobind+0x25d/0x750 net/ax25/ax25_route.c:424
 ax25_connect.cold+0x30/0xa4 net/ax25/af_ax25.c:1224
 __sys_connect+0x357/0x490 net/socket.c:1664
 __do_sys_connect net/socket.c:1675 [inline]
 __se_sys_connect net/socket.c:1672 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1672
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458099
Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f870ee22c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458099
RDX: 0000000000000048 RSI: 0000000020000080 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
ax25_connect(): syz-executor4 uses autobind, please contact jreuter@yaina.de
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f870ee236d4
R13: 00000000004be48e R14: 00000000004ce9a8 R15: 00000000ffffffff

Allocated by task 526:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
ax25_connect(): syz-executor5 uses autobind, please contact jreuter@yaina.de
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3609
 kmalloc include/linux/slab.h:545 [inline]
 ax25_rt_add net/ax25/ax25_route.c:95 [inline]
 ax25_rt_ioctl+0x3b9/0x1270 net/ax25/ax25_route.c:233
 ax25_ioctl+0x322/0x10b0 net/ax25/af_ax25.c:1763
 sock_do_ioctl+0xe2/0x400 net/socket.c:950
 sock_ioctl+0x32f/0x6c0 net/socket.c:1074
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

ax25_connect(): syz-executor5 uses autobind, please contact jreuter@yaina.de
Freed by task 550:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466
 __cache_free mm/slab.c:3487 [inline]
 kfree+0xcf/0x230 mm/slab.c:3806
 ax25_rt_add net/ax25/ax25_route.c:92 [inline]
 ax25_rt_ioctl+0x304/0x1270 net/ax25/ax25_route.c:233
 ax25_ioctl+0x322/0x10b0 net/ax25/af_ax25.c:1763
 sock_do_ioctl+0xe2/0x400 net/socket.c:950
 sock_ioctl+0x32f/0x6c0 net/socket.c:1074
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x107b/0x17d0 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888066641a80
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 0 bytes inside of
 96-byte region [ffff888066641a80, ffff888066641ae0)
The buggy address belongs to the page:
page:ffffea0001999040 count:1 mapcount:0 mapping:ffff88812c3f04c0 index:0x0
flags: 0x1fffc0000000200(slab)
ax25_connect(): syz-executor4 uses autobind, please contact jreuter@yaina.de
raw: 01fffc0000000200 ffffea0001817948 ffffea0002341dc8 ffff88812c3f04c0
raw: 0000000000000000 ffff888066641000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888066641980: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888066641a00: 00 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc
&gt;ffff888066641a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                   ^
 ffff888066641b00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888066641b80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ax25: fix a use-after-free in ax25_fillin_cb()</title>
<updated>2019-01-09T16:38:30+00:00</updated>
<author>
<name>Cong Wang</name>
<email>xiyou.wangcong@gmail.com</email>
</author>
<published>2018-12-29T21:56:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=3e881d8764ed9b04ae3e5c3e5d132acb75ef91ba'/>
<id>3e881d8764ed9b04ae3e5c3e5d132acb75ef91ba</id>
<content type='text'>
[ Upstream commit c433570458e49bccea5c551df628d058b3526289 ]

There are multiple issues here:

1. After freeing dev-&gt;ax25_ptr, we need to set it to NULL otherwise
   we may use a dangling pointer.

2. There is a race between ax25_setsockopt() and device notifier as
   reported by syzbot. Close it by holding RTNL lock.

3. We need to test if dev-&gt;ax25_ptr is NULL before using it.

Reported-and-tested-by: syzbot+ae6bb869cbed29b29040@syzkaller.appspotmail.com
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c433570458e49bccea5c551df628d058b3526289 ]

There are multiple issues here:

1. After freeing dev-&gt;ax25_ptr, we need to set it to NULL otherwise
   we may use a dangling pointer.

2. There is a race between ax25_setsockopt() and device notifier as
   reported by syzbot. Close it by holding RTNL lock.

3. We need to test if dev-&gt;ax25_ptr is NULL before using it.

Reported-and-tested-by: syzbot+ae6bb869cbed29b29040@syzkaller.appspotmail.com
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ax25: remove blank line at EOF</title>
<updated>2018-07-24T21:10:42+00:00</updated>
<author>
<name>Stephen Hemminger</name>
<email>stephen@networkplumber.org</email>
</author>
<published>2018-07-24T19:29:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9d82a1cdd391e84bfe5d70702ad4efe5be7d2236'/>
<id>9d82a1cdd391e84bfe5d70702ad4efe5be7d2236</id>
<content type='text'>
Signed-off-by: Stephen Hemminger &lt;stephen@networkplumber.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Stephen Hemminger &lt;stephen@networkplumber.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert changes to convert to -&gt;poll_mask() and aio IOCB_CMD_POLL</title>
<updated>2018-06-28T17:40:47+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-06-28T16:43:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=a11e1d432b51f63ba698d044441284a661f01144'/>
<id>a11e1d432b51f63ba698d044441284a661f01144</id>
<content type='text'>
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"-&gt;poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"-&gt;get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"-&gt;poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"-&gt;get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
