<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/tipc, branch v5.4.294</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>tipc: fix NULL pointer dereference in tipc_mon_reinit_self()</title>
<updated>2025-05-02T05:39:25+00:00</updated>
<author>
<name>Tung Nguyen</name>
<email>tung.quang.nguyen@est.tech</email>
</author>
<published>2025-04-17T07:47:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a3df56010403b2cd26388096ebccf959d23c4dcc'/>
<id>a3df56010403b2cd26388096ebccf959d23c4dcc</id>
<content type='text'>
[ Upstream commit d63527e109e811ef11abb1c2985048fdb528b4cb ]

syzbot reported:

tipc: Node number set to 1055423674
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 3 UID: 0 PID: 6017 Comm: kworker/3:5 Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events tipc_net_finalize_work
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 &lt;TASK&gt;
 tipc_net_finalize+0x10b/0x180 net/tipc/net.c:140
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 &lt;/TASK&gt;
...
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

There is a racing condition between workqueue created when enabling
bearer and another thread created when disabling bearer right after
that as follow:

enabling_bearer                          | disabling_bearer
---------------                          | ----------------
tipc_disc_timeout()                      |
{                                        | bearer_disable()
 ...                                     | {
 schedule_work(&amp;tn-&gt;work);               |  tipc_mon_delete()
 ...                                     |  {
}                                        |   ...
                                         |   write_lock_bh(&amp;mon-&gt;lock);
                                         |   mon-&gt;self = NULL;
                                         |   write_unlock_bh(&amp;mon-&gt;lock);
                                         |   ...
                                         |  }
tipc_net_finalize_work()                 | }
{                                        |
 ...                                     |
 tipc_net_finalize()                     |
 {                                       |
  ...                                    |
  tipc_mon_reinit_self()                 |
  {                                      |
   ...                                   |
   write_lock_bh(&amp;mon-&gt;lock);            |
   mon-&gt;self-&gt;addr = tipc_own_addr(net); |
   write_unlock_bh(&amp;mon-&gt;lock);          |
   ...                                   |
  }                                      |
  ...                                    |
 }                                       |
 ...                                     |
}                                        |

'mon-&gt;self' is set to NULL in disabling_bearer thread and dereferenced
later in enabling_bearer thread.

This commit fixes this issue by validating 'mon-&gt;self' before assigning
node address to it.

Reported-by: syzbot+ed60da8d686dc709164c@syzkaller.appspotmail.com
Fixes: 46cb01eeeb86 ("tipc: update mon's self addr when node addr generated")
Signed-off-by: Tung Nguyen &lt;tung.quang.nguyen@est.tech&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20250417074826.578115-1-tung.quang.nguyen@est.tech
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d63527e109e811ef11abb1c2985048fdb528b4cb ]

syzbot reported:

tipc: Node number set to 1055423674
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 3 UID: 0 PID: 6017 Comm: kworker/3:5 Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events tipc_net_finalize_work
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 &lt;TASK&gt;
 tipc_net_finalize+0x10b/0x180 net/tipc/net.c:140
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 &lt;/TASK&gt;
...
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

There is a racing condition between workqueue created when enabling
bearer and another thread created when disabling bearer right after
that as follow:

enabling_bearer                          | disabling_bearer
---------------                          | ----------------
tipc_disc_timeout()                      |
{                                        | bearer_disable()
 ...                                     | {
 schedule_work(&amp;tn-&gt;work);               |  tipc_mon_delete()
 ...                                     |  {
}                                        |   ...
                                         |   write_lock_bh(&amp;mon-&gt;lock);
                                         |   mon-&gt;self = NULL;
                                         |   write_unlock_bh(&amp;mon-&gt;lock);
                                         |   ...
                                         |  }
tipc_net_finalize_work()                 | }
{                                        |
 ...                                     |
 tipc_net_finalize()                     |
 {                                       |
  ...                                    |
  tipc_mon_reinit_self()                 |
  {                                      |
   ...                                   |
   write_lock_bh(&amp;mon-&gt;lock);            |
   mon-&gt;self-&gt;addr = tipc_own_addr(net); |
   write_unlock_bh(&amp;mon-&gt;lock);          |
   ...                                   |
  }                                      |
  ...                                    |
 }                                       |
 ...                                     |
}                                        |

'mon-&gt;self' is set to NULL in disabling_bearer thread and dereferenced
later in enabling_bearer thread.

This commit fixes this issue by validating 'mon-&gt;self' before assigning
node address to it.

Reported-by: syzbot+ed60da8d686dc709164c@syzkaller.appspotmail.com
Fixes: 46cb01eeeb86 ("tipc: update mon's self addr when node addr generated")
Signed-off-by: Tung Nguyen &lt;tung.quang.nguyen@est.tech&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20250417074826.578115-1-tung.quang.nguyen@est.tech
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix memory leak in tipc_link_xmit</title>
<updated>2025-05-02T05:39:08+00:00</updated>
<author>
<name>Tung Nguyen</name>
<email>tung.quang.nguyen@est.tech</email>
</author>
<published>2025-04-03T09:24:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=84895f5ce3829d9fc030e5ec2d8729da4c0c9d08'/>
<id>84895f5ce3829d9fc030e5ec2d8729da4c0c9d08</id>
<content type='text'>
[ Upstream commit 69ae94725f4fc9e75219d2d69022029c5b24bc9a ]

In case the backlog transmit queue for system-importance messages is overloaded,
tipc_link_xmit() returns -ENOBUFS but the skb list is not purged. This leads to
memory leak and failure when a skb is allocated.

This commit fixes this issue by purging the skb list before tipc_link_xmit()
returns.

Fixes: 365ad353c256 ("tipc: reduce risk of user starvation during link congestion")
Signed-off-by: Tung Nguyen &lt;tung.quang.nguyen@est.tech&gt;
Link: https://patch.msgid.link/20250403092431.514063-1-tung.quang.nguyen@est.tech
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 69ae94725f4fc9e75219d2d69022029c5b24bc9a ]

In case the backlog transmit queue for system-importance messages is overloaded,
tipc_link_xmit() returns -ENOBUFS but the skb list is not purged. This leads to
memory leak and failure when a skb is allocated.

This commit fixes this issue by purging the skb list before tipc_link_xmit()
returns.

Fixes: 365ad353c256 ("tipc: reduce risk of user starvation during link congestion")
Signed-off-by: Tung Nguyen &lt;tung.quang.nguyen@est.tech&gt;
Link: https://patch.msgid.link/20250403092431.514063-1-tung.quang.nguyen@est.tech
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix NULL deref in cleanup_bearer()</title>
<updated>2024-12-19T17:05:03+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2024-12-04T17:05:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d1d4dfb189a115734bff81c411bc58d9e348db7d'/>
<id>d1d4dfb189a115734bff81c411bc58d9e348db7d</id>
<content type='text'>
[ Upstream commit b04d86fff66b15c07505d226431f808c15b1703c ]

syzbot found [1] that after blamed commit, ub-&gt;ubsock-&gt;sk
was NULL when attempting the atomic_dec() :

atomic_dec(&amp;tipc_net(sock_net(ub-&gt;ubsock-&gt;sk))-&gt;wq_count);

Fix this by caching the tipc_net pointer.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 5896 Comm: kworker/0:3 Not tainted 6.13.0-rc1-next-20241203-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events cleanup_bearer
 RIP: 0010:read_pnet include/net/net_namespace.h:387 [inline]
 RIP: 0010:sock_net include/net/sock.h:655 [inline]
 RIP: 0010:cleanup_bearer+0x1f7/0x280 net/tipc/udp_media.c:820
Code: 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 3c f7 99 f6 48 8b 1b 48 83 c3 30 e8 f0 e4 60 00 48 89 d8 48 c1 e8 03 &lt;42&gt; 80 3c 28 00 74 08 48 89 df e8 1a f7 99 f6 49 83 c7 e8 48 8b 1b
RSP: 0018:ffffc9000410fb70 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88802fe45a00
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410f900
RBP: ffff88807e1f0908 R08: ffffc9000410f907 R09: 1ffff92000821f20
R10: dffffc0000000000 R11: fffff52000821f21 R12: ffff888031d19980
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807e1f0918
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ca050b000 CR3: 0000000031c0c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 6a2fa13312e5 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Reported-by: syzbot+46aa5474f179dacd1a3b@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67508b5f.050a0220.17bd51.0070.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://patch.msgid.link/20241204170548.4152658-1-edumazet@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b04d86fff66b15c07505d226431f808c15b1703c ]

syzbot found [1] that after blamed commit, ub-&gt;ubsock-&gt;sk
was NULL when attempting the atomic_dec() :

atomic_dec(&amp;tipc_net(sock_net(ub-&gt;ubsock-&gt;sk))-&gt;wq_count);

Fix this by caching the tipc_net pointer.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 5896 Comm: kworker/0:3 Not tainted 6.13.0-rc1-next-20241203-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events cleanup_bearer
 RIP: 0010:read_pnet include/net/net_namespace.h:387 [inline]
 RIP: 0010:sock_net include/net/sock.h:655 [inline]
 RIP: 0010:cleanup_bearer+0x1f7/0x280 net/tipc/udp_media.c:820
Code: 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 3c f7 99 f6 48 8b 1b 48 83 c3 30 e8 f0 e4 60 00 48 89 d8 48 c1 e8 03 &lt;42&gt; 80 3c 28 00 74 08 48 89 df e8 1a f7 99 f6 49 83 c7 e8 48 8b 1b
RSP: 0018:ffffc9000410fb70 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88802fe45a00
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410f900
RBP: ffff88807e1f0908 R08: ffffc9000410f907 R09: 1ffff92000821f20
R10: dffffc0000000000 R11: fffff52000821f21 R12: ffff888031d19980
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807e1f0918
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ca050b000 CR3: 0000000031c0c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 6a2fa13312e5 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Reported-by: syzbot+46aa5474f179dacd1a3b@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67508b5f.050a0220.17bd51.0070.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://patch.msgid.link/20241204170548.4152658-1-edumazet@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: Fix use-after-free of kernel socket in cleanup_bearer().</title>
<updated>2024-12-14T18:44:46+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2024-11-27T05:05:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4e69457f9dfae67435f3ccf29008768eae860415'/>
<id>4e69457f9dfae67435f3ccf29008768eae860415</id>
<content type='text'>
[ Upstream commit 6a2fa13312e51a621f652d522d7e2df7066330b6 ]

syzkaller reported a use-after-free of UDP kernel socket
in cleanup_bearer() without repro. [0][1]

When bearer_disable() calls tipc_udp_disable(), cleanup
of the UDP kernel socket is deferred by work calling
cleanup_bearer().

tipc_net_stop() waits for such works to finish by checking
tipc_net(net)-&gt;wq_count.  However, the work decrements the
count too early before releasing the kernel socket,
unblocking cleanup_net() and resulting in use-after-free.

Let's move the decrement after releasing the socket in
cleanup_bearer().

[0]:
ref_tracker: net notrefcnt@000000009b3d1faf has 1/1 users at
     sk_alloc+0x438/0x608
     inet_create+0x4c8/0xcb0
     __sock_create+0x350/0x6b8
     sock_create_kern+0x58/0x78
     udp_sock_create4+0x68/0x398
     udp_sock_create+0x88/0xc8
     tipc_udp_enable+0x5e8/0x848
     __tipc_nl_bearer_enable+0x84c/0xed8
     tipc_nl_bearer_enable+0x38/0x60
     genl_family_rcv_msg_doit+0x170/0x248
     genl_rcv_msg+0x400/0x5b0
     netlink_rcv_skb+0x1dc/0x398
     genl_rcv+0x44/0x68
     netlink_unicast+0x678/0x8b0
     netlink_sendmsg+0x5e4/0x898
     ____sys_sendmsg+0x500/0x830

[1]:
BUG: KMSAN: use-after-free in udp_hashslot include/net/udp.h:85 [inline]
BUG: KMSAN: use-after-free in udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979
 udp_hashslot include/net/udp.h:85 [inline]
 udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979
 sk_common_release+0xaf/0x3f0 net/core/sock.c:3820
 inet_release+0x1e0/0x260 net/ipv4/af_inet.c:437
 inet6_release+0x6f/0xd0 net/ipv6/af_inet6.c:489
 __sock_release net/socket.c:658 [inline]
 sock_release+0xa0/0x210 net/socket.c:686
 cleanup_bearer+0x42d/0x4c0 net/tipc/udp_media.c:819
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310
 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391
 kthread+0x531/0x6b0 kernel/kthread.c:389
 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244

Uninit was created at:
 slab_free_hook mm/slub.c:2269 [inline]
 slab_free mm/slub.c:4580 [inline]
 kmem_cache_free+0x207/0xc40 mm/slub.c:4682
 net_free net/core/net_namespace.c:454 [inline]
 cleanup_net+0x16f2/0x19d0 net/core/net_namespace.c:647
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310
 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391
 kthread+0x531/0x6b0 kernel/kthread.c:389
 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244

CPU: 0 UID: 0 PID: 54 Comm: kworker/0:2 Not tainted 6.12.0-rc1-00131-gf66ebf37d69c #7 91723d6f74857f70725e1583cba3cf4adc716cfa
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: events cleanup_bearer

Fixes: 26abe14379f8 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.")
Reported-by: syzkaller &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://patch.msgid.link/20241127050512.28438-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6a2fa13312e51a621f652d522d7e2df7066330b6 ]

syzkaller reported a use-after-free of UDP kernel socket
in cleanup_bearer() without repro. [0][1]

When bearer_disable() calls tipc_udp_disable(), cleanup
of the UDP kernel socket is deferred by work calling
cleanup_bearer().

tipc_net_stop() waits for such works to finish by checking
tipc_net(net)-&gt;wq_count.  However, the work decrements the
count too early before releasing the kernel socket,
unblocking cleanup_net() and resulting in use-after-free.

Let's move the decrement after releasing the socket in
cleanup_bearer().

[0]:
ref_tracker: net notrefcnt@000000009b3d1faf has 1/1 users at
     sk_alloc+0x438/0x608
     inet_create+0x4c8/0xcb0
     __sock_create+0x350/0x6b8
     sock_create_kern+0x58/0x78
     udp_sock_create4+0x68/0x398
     udp_sock_create+0x88/0xc8
     tipc_udp_enable+0x5e8/0x848
     __tipc_nl_bearer_enable+0x84c/0xed8
     tipc_nl_bearer_enable+0x38/0x60
     genl_family_rcv_msg_doit+0x170/0x248
     genl_rcv_msg+0x400/0x5b0
     netlink_rcv_skb+0x1dc/0x398
     genl_rcv+0x44/0x68
     netlink_unicast+0x678/0x8b0
     netlink_sendmsg+0x5e4/0x898
     ____sys_sendmsg+0x500/0x830

[1]:
BUG: KMSAN: use-after-free in udp_hashslot include/net/udp.h:85 [inline]
BUG: KMSAN: use-after-free in udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979
 udp_hashslot include/net/udp.h:85 [inline]
 udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979
 sk_common_release+0xaf/0x3f0 net/core/sock.c:3820
 inet_release+0x1e0/0x260 net/ipv4/af_inet.c:437
 inet6_release+0x6f/0xd0 net/ipv6/af_inet6.c:489
 __sock_release net/socket.c:658 [inline]
 sock_release+0xa0/0x210 net/socket.c:686
 cleanup_bearer+0x42d/0x4c0 net/tipc/udp_media.c:819
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310
 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391
 kthread+0x531/0x6b0 kernel/kthread.c:389
 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244

Uninit was created at:
 slab_free_hook mm/slub.c:2269 [inline]
 slab_free mm/slub.c:4580 [inline]
 kmem_cache_free+0x207/0xc40 mm/slub.c:4682
 net_free net/core/net_namespace.c:454 [inline]
 cleanup_net+0x16f2/0x19d0 net/core/net_namespace.c:647
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310
 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391
 kthread+0x531/0x6b0 kernel/kthread.c:389
 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244

CPU: 0 UID: 0 PID: 54 Comm: kworker/0:2 Not tainted 6.12.0-rc1-00131-gf66ebf37d69c #7 91723d6f74857f70725e1583cba3cf4adc716cfa
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: events cleanup_bearer

Fixes: 26abe14379f8 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.")
Reported-by: syzkaller &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Link: https://patch.msgid.link/20241127050512.28438-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: enable creating a "preliminary" node</title>
<updated>2024-12-14T18:44:45+00:00</updated>
<author>
<name>Tuong Lien</name>
<email>tuong.t.lien@dektech.com.au</email>
</author>
<published>2019-11-08T05:05:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0b8f0026bbd4df1688e1726026476e60762daf2a'/>
<id>0b8f0026bbd4df1688e1726026476e60762daf2a</id>
<content type='text'>
[ Upstream commit 4cbf8ac2fe5a0846508fe02b95a5de1a90fa73f4 ]

When user sets RX key for a peer not existing on the own node, a new
node entry is needed to which the RX key will be attached. However,
since the peer node address (&amp; capabilities) is unknown at that moment,
only the node-ID is provided, this commit allows the creation of a node
with only the data that we call as “preliminary”.

A preliminary node is not the object of the “tipc_node_find()” but the
“tipc_node_find_by_id()”. Once the first message i.e. LINK_CONFIG comes
from that peer, and is successfully decrypted by the own node, the
actual peer node data will be properly updated and the node will
function as usual.

In addition, the node timer always starts when a node object is created
so if a preliminary node is not used, it will be cleaned up.

The later encryption functions will also use the node timer and be able
to create a preliminary node automatically when needed.

Acked-by: Ying Xue &lt;ying.xue@windreiver.com&gt;
Acked-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 6a2fa13312e5 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4cbf8ac2fe5a0846508fe02b95a5de1a90fa73f4 ]

When user sets RX key for a peer not existing on the own node, a new
node entry is needed to which the RX key will be attached. However,
since the peer node address (&amp; capabilities) is unknown at that moment,
only the node-ID is provided, this commit allows the creation of a node
with only the data that we call as “preliminary”.

A preliminary node is not the object of the “tipc_node_find()” but the
“tipc_node_find_by_id()”. Once the first message i.e. LINK_CONFIG comes
from that peer, and is successfully decrypted by the own node, the
actual peer node data will be properly updated and the node will
function as usual.

In addition, the node timer always starts when a node object is created
so if a preliminary node is not used, it will be cleaned up.

The later encryption functions will also use the node timer and be able
to create a preliminary node automatically when needed.

Acked-by: Ying Xue &lt;ying.xue@windreiver.com&gt;
Acked-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 6a2fa13312e5 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: add reference counter to bearer</title>
<updated>2024-12-14T18:44:45+00:00</updated>
<author>
<name>Tuong Lien</name>
<email>tuong.t.lien@dektech.com.au</email>
</author>
<published>2019-11-08T05:05:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6b7fbc30ec69c49c183390acccf6e7ee3076316f'/>
<id>6b7fbc30ec69c49c183390acccf6e7ee3076316f</id>
<content type='text'>
[ Upstream commit 2a7ee696f7b000a970dcce0cb06fdcd0a9e6ee76 ]

As a need to support the crypto asynchronous operations in the later
commits, apart from the current RCU mechanism for bearer pointer, we
add a 'refcnt' to the bearer object as well.

So, a bearer can be hold via 'tipc_bearer_hold()' without being freed
even though the bearer or interface can be disabled in the meanwhile.
If that happens, the bearer will be released then when the crypto
operation is completed and 'tipc_bearer_put()' is called.

Acked-by: Ying Xue &lt;ying.xue@windreiver.com&gt;
Acked-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 6a2fa13312e5 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2a7ee696f7b000a970dcce0cb06fdcd0a9e6ee76 ]

As a need to support the crypto asynchronous operations in the later
commits, apart from the current RCU mechanism for bearer pointer, we
add a 'refcnt' to the bearer object as well.

So, a bearer can be hold via 'tipc_bearer_hold()' without being freed
even though the bearer or interface can be disabled in the meanwhile.
If that happens, the bearer will be released then when the crypto
operation is completed and 'tipc_bearer_put()' is called.

Acked-by: Ying Xue &lt;ying.xue@windreiver.com&gt;
Acked-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 6a2fa13312e5 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: guard against string buffer overrun</title>
<updated>2024-11-08T15:20:37+00:00</updated>
<author>
<name>Simon Horman</name>
<email>horms@kernel.org</email>
</author>
<published>2024-08-01T18:35:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c79768ffba5b6e95569a463a69b3101c95694867'/>
<id>c79768ffba5b6e95569a463a69b3101c95694867</id>
<content type='text'>
[ Upstream commit 6555a2a9212be6983d2319d65276484f7c5f431a ]

Smatch reports that copying media_name and if_name to name_parts may
overwrite the destination.

 .../bearer.c:166 bearer_name_validate() error: strcpy() 'media_name' too large for 'name_parts-&gt;media_name' (32 vs 16)
 .../bearer.c:167 bearer_name_validate() error: strcpy() 'if_name' too large for 'name_parts-&gt;if_name' (1010102 vs 16)

This does seem to be the case so guard against this possibility by using
strscpy() and failing if truncation occurs.

Introduced by commit b97bf3fd8f6a ("[TIPC] Initial merge")

Compile tested only.

Reviewed-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20240801-tipic-overrun-v2-1-c5b869d1f074@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6555a2a9212be6983d2319d65276484f7c5f431a ]

Smatch reports that copying media_name and if_name to name_parts may
overwrite the destination.

 .../bearer.c:166 bearer_name_validate() error: strcpy() 'media_name' too large for 'name_parts-&gt;media_name' (32 vs 16)
 .../bearer.c:167 bearer_name_validate() error: strcpy() 'if_name' too large for 'name_parts-&gt;if_name' (1010102 vs 16)

This does seem to be the case so guard against this possibility by using
strscpy() and failing if truncation occurs.

Introduced by commit b97bf3fd8f6a ("[TIPC] Initial merge")

Compile tested only.

Reviewed-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Simon Horman &lt;horms@kernel.org&gt;
Link: https://patch.msgid.link/20240801-tipic-overrun-v2-1-c5b869d1f074@kernel.org
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: tipc: avoid possible garbage value</title>
<updated>2024-11-08T15:20:27+00:00</updated>
<author>
<name>Su Hui</name>
<email>suhui@nfschina.com</email>
</author>
<published>2024-09-12T11:01:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c3026230d2907111a085fbe207985cfdf5fea1ea'/>
<id>c3026230d2907111a085fbe207985cfdf5fea1ea</id>
<content type='text'>
[ Upstream commit 99655a304e450baaae6b396cb942b9e47659d644 ]

Clang static checker (scan-build) warning:
net/tipc/bcast.c:305:4:
The expression is an uninitialized value. The computed value will also
be garbage [core.uninitialized.Assign]
  305 |                         (*cong_link_cnt)++;
      |                         ^~~~~~~~~~~~~~~~~~

tipc_rcast_xmit() will increase cong_link_cnt's value, but cong_link_cnt
is uninitialized. Although it won't really cause a problem, it's better
to fix it.

Fixes: dca4a17d24ee ("tipc: fix potential hanging after b/rcast changing")
Signed-off-by: Su Hui &lt;suhui@nfschina.com&gt;
Reviewed-by: Justin Stitt &lt;justinstitt@google.com&gt;
Link: https://patch.msgid.link/20240912110119.2025503-1-suhui@nfschina.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 99655a304e450baaae6b396cb942b9e47659d644 ]

Clang static checker (scan-build) warning:
net/tipc/bcast.c:305:4:
The expression is an uninitialized value. The computed value will also
be garbage [core.uninitialized.Assign]
  305 |                         (*cong_link_cnt)++;
      |                         ^~~~~~~~~~~~~~~~~~

tipc_rcast_xmit() will increase cong_link_cnt's value, but cong_link_cnt
is uninitialized. Although it won't really cause a problem, it's better
to fix it.

Fixes: dca4a17d24ee ("tipc: fix potential hanging after b/rcast changing")
Signed-off-by: Su Hui &lt;suhui@nfschina.com&gt;
Reviewed-by: Justin Stitt &lt;justinstitt@google.com&gt;
Link: https://patch.msgid.link/20240912110119.2025503-1-suhui@nfschina.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: Return non-zero value from tipc_udp_addr2str() on error</title>
<updated>2024-08-19T03:33:41+00:00</updated>
<author>
<name>Shigeru Yoshida</name>
<email>syoshida@redhat.com</email>
</author>
<published>2024-07-16T02:09:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=253405541be2f15ffebdeac2f4cf4b7e9144d12f'/>
<id>253405541be2f15ffebdeac2f4cf4b7e9144d12f</id>
<content type='text'>
[ Upstream commit fa96c6baef1b5385e2f0c0677b32b3839e716076 ]

tipc_udp_addr2str() should return non-zero value if the UDP media
address is invalid. Otherwise, a buffer overflow access can occur in
tipc_media_addr_printf(). Fix this by returning 1 on an invalid UDP
media address.

Fixes: d0f91938bede ("tipc: add ip/udp media type")
Signed-off-by: Shigeru Yoshida &lt;syoshida@redhat.com&gt;
Reviewed-by: Tung Nguyen &lt;tung.q.nguyen@endava.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit fa96c6baef1b5385e2f0c0677b32b3839e716076 ]

tipc_udp_addr2str() should return non-zero value if the UDP media
address is invalid. Otherwise, a buffer overflow access can occur in
tipc_media_addr_printf(). Fix this by returning 1 on an invalid UDP
media address.

Fixes: d0f91938bede ("tipc: add ip/udp media type")
Signed-off-by: Shigeru Yoshida &lt;syoshida@redhat.com&gt;
Reviewed-by: Tung Nguyen &lt;tung.q.nguyen@endava.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix UAF in error path</title>
<updated>2024-05-17T09:43:55+00:00</updated>
<author>
<name>Paolo Abeni</name>
<email>pabeni@redhat.com</email>
</author>
<published>2024-04-30T13:53:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=93bc2d6d16f2c3178736ba6b845b30475856dc40'/>
<id>93bc2d6d16f2c3178736ba6b845b30475856dc40</id>
<content type='text'>
commit 080cbb890286cd794f1ee788bbc5463e2deb7c2b upstream.

Sam Page (sam4k) working with Trend Micro Zero Day Initiative reported
a UAF in the tipc_buf_append() error path:

BUG: KASAN: slab-use-after-free in kfree_skb_list_reason+0x47e/0x4c0
linux/net/core/skbuff.c:1183
Read of size 8 at addr ffff88804d2a7c80 by task poc/8034

CPU: 1 PID: 8034 Comm: poc Not tainted 6.8.2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.0-debian-1.16.0-5 04/01/2014
Call Trace:
 &lt;IRQ&gt;
 __dump_stack linux/lib/dump_stack.c:88
 dump_stack_lvl+0xd9/0x1b0 linux/lib/dump_stack.c:106
 print_address_description linux/mm/kasan/report.c:377
 print_report+0xc4/0x620 linux/mm/kasan/report.c:488
 kasan_report+0xda/0x110 linux/mm/kasan/report.c:601
 kfree_skb_list_reason+0x47e/0x4c0 linux/net/core/skbuff.c:1183
 skb_release_data+0x5af/0x880 linux/net/core/skbuff.c:1026
 skb_release_all linux/net/core/skbuff.c:1094
 __kfree_skb linux/net/core/skbuff.c:1108
 kfree_skb_reason+0x12d/0x210 linux/net/core/skbuff.c:1144
 kfree_skb linux/./include/linux/skbuff.h:1244
 tipc_buf_append+0x425/0xb50 linux/net/tipc/msg.c:186
 tipc_link_input+0x224/0x7c0 linux/net/tipc/link.c:1324
 tipc_link_rcv+0x76e/0x2d70 linux/net/tipc/link.c:1824
 tipc_rcv+0x45f/0x10f0 linux/net/tipc/node.c:2159
 tipc_udp_recv+0x73b/0x8f0 linux/net/tipc/udp_media.c:390
 udp_queue_rcv_one_skb+0xad2/0x1850 linux/net/ipv4/udp.c:2108
 udp_queue_rcv_skb+0x131/0xb00 linux/net/ipv4/udp.c:2186
 udp_unicast_rcv_skb+0x165/0x3b0 linux/net/ipv4/udp.c:2346
 __udp4_lib_rcv+0x2594/0x3400 linux/net/ipv4/udp.c:2422
 ip_protocol_deliver_rcu+0x30c/0x4e0 linux/net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2e4/0x520 linux/net/ipv4/ip_input.c:233
 NF_HOOK linux/./include/linux/netfilter.h:314
 NF_HOOK linux/./include/linux/netfilter.h:308
 ip_local_deliver+0x18e/0x1f0 linux/net/ipv4/ip_input.c:254
 dst_input linux/./include/net/dst.h:461
 ip_rcv_finish linux/net/ipv4/ip_input.c:449
 NF_HOOK linux/./include/linux/netfilter.h:314
 NF_HOOK linux/./include/linux/netfilter.h:308
 ip_rcv+0x2c5/0x5d0 linux/net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core+0x199/0x1e0 linux/net/core/dev.c:5534
 __netif_receive_skb+0x1f/0x1c0 linux/net/core/dev.c:5648
 process_backlog+0x101/0x6b0 linux/net/core/dev.c:5976
 __napi_poll.constprop.0+0xba/0x550 linux/net/core/dev.c:6576
 napi_poll linux/net/core/dev.c:6645
 net_rx_action+0x95a/0xe90 linux/net/core/dev.c:6781
 __do_softirq+0x21f/0x8e7 linux/kernel/softirq.c:553
 do_softirq linux/kernel/softirq.c:454
 do_softirq+0xb2/0xf0 linux/kernel/softirq.c:441
 &lt;/IRQ&gt;
 &lt;TASK&gt;
 __local_bh_enable_ip+0x100/0x120 linux/kernel/softirq.c:381
 local_bh_enable linux/./include/linux/bottom_half.h:33
 rcu_read_unlock_bh linux/./include/linux/rcupdate.h:851
 __dev_queue_xmit+0x871/0x3ee0 linux/net/core/dev.c:4378
 dev_queue_xmit linux/./include/linux/netdevice.h:3169
 neigh_hh_output linux/./include/net/neighbour.h:526
 neigh_output linux/./include/net/neighbour.h:540
 ip_finish_output2+0x169f/0x2550 linux/net/ipv4/ip_output.c:235
 __ip_finish_output linux/net/ipv4/ip_output.c:313
 __ip_finish_output+0x49e/0x950 linux/net/ipv4/ip_output.c:295
 ip_finish_output+0x31/0x310 linux/net/ipv4/ip_output.c:323
 NF_HOOK_COND linux/./include/linux/netfilter.h:303
 ip_output+0x13b/0x2a0 linux/net/ipv4/ip_output.c:433
 dst_output linux/./include/net/dst.h:451
 ip_local_out linux/net/ipv4/ip_output.c:129
 ip_send_skb+0x3e5/0x560 linux/net/ipv4/ip_output.c:1492
 udp_send_skb+0x73f/0x1530 linux/net/ipv4/udp.c:963
 udp_sendmsg+0x1a36/0x2b40 linux/net/ipv4/udp.c:1250
 inet_sendmsg+0x105/0x140 linux/net/ipv4/af_inet.c:850
 sock_sendmsg_nosec linux/net/socket.c:730
 __sock_sendmsg linux/net/socket.c:745
 __sys_sendto+0x42c/0x4e0 linux/net/socket.c:2191
 __do_sys_sendto linux/net/socket.c:2203
 __se_sys_sendto linux/net/socket.c:2199
 __x64_sys_sendto+0xe0/0x1c0 linux/net/socket.c:2199
 do_syscall_x64 linux/arch/x86/entry/common.c:52
 do_syscall_64+0xd8/0x270 linux/arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77 linux/arch/x86/entry/entry_64.S:120
RIP: 0033:0x7f3434974f29
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 8b 0d 37 8f 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007fff9154f2b8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3434974f29
RDX: 00000000000032c8 RSI: 00007fff9154f300 RDI: 0000000000000003
RBP: 00007fff915532e0 R08: 00007fff91553360 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000212 R12: 000055ed86d261d0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 &lt;/TASK&gt;

In the critical scenario, either the relevant skb is freed or its
ownership is transferred into a frag_lists. In both cases, the cleanup
code must not free it again: we need to clear the skb reference earlier.

Fixes: 1149557d64c9 ("tipc: eliminate unnecessary linearization of incoming buffers")
Cc: stable@vger.kernel.org
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-23852
Acked-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/752f1ccf762223d109845365d07f55414058e5a3.1714484273.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&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 080cbb890286cd794f1ee788bbc5463e2deb7c2b upstream.

Sam Page (sam4k) working with Trend Micro Zero Day Initiative reported
a UAF in the tipc_buf_append() error path:

BUG: KASAN: slab-use-after-free in kfree_skb_list_reason+0x47e/0x4c0
linux/net/core/skbuff.c:1183
Read of size 8 at addr ffff88804d2a7c80 by task poc/8034

CPU: 1 PID: 8034 Comm: poc Not tainted 6.8.2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.0-debian-1.16.0-5 04/01/2014
Call Trace:
 &lt;IRQ&gt;
 __dump_stack linux/lib/dump_stack.c:88
 dump_stack_lvl+0xd9/0x1b0 linux/lib/dump_stack.c:106
 print_address_description linux/mm/kasan/report.c:377
 print_report+0xc4/0x620 linux/mm/kasan/report.c:488
 kasan_report+0xda/0x110 linux/mm/kasan/report.c:601
 kfree_skb_list_reason+0x47e/0x4c0 linux/net/core/skbuff.c:1183
 skb_release_data+0x5af/0x880 linux/net/core/skbuff.c:1026
 skb_release_all linux/net/core/skbuff.c:1094
 __kfree_skb linux/net/core/skbuff.c:1108
 kfree_skb_reason+0x12d/0x210 linux/net/core/skbuff.c:1144
 kfree_skb linux/./include/linux/skbuff.h:1244
 tipc_buf_append+0x425/0xb50 linux/net/tipc/msg.c:186
 tipc_link_input+0x224/0x7c0 linux/net/tipc/link.c:1324
 tipc_link_rcv+0x76e/0x2d70 linux/net/tipc/link.c:1824
 tipc_rcv+0x45f/0x10f0 linux/net/tipc/node.c:2159
 tipc_udp_recv+0x73b/0x8f0 linux/net/tipc/udp_media.c:390
 udp_queue_rcv_one_skb+0xad2/0x1850 linux/net/ipv4/udp.c:2108
 udp_queue_rcv_skb+0x131/0xb00 linux/net/ipv4/udp.c:2186
 udp_unicast_rcv_skb+0x165/0x3b0 linux/net/ipv4/udp.c:2346
 __udp4_lib_rcv+0x2594/0x3400 linux/net/ipv4/udp.c:2422
 ip_protocol_deliver_rcu+0x30c/0x4e0 linux/net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2e4/0x520 linux/net/ipv4/ip_input.c:233
 NF_HOOK linux/./include/linux/netfilter.h:314
 NF_HOOK linux/./include/linux/netfilter.h:308
 ip_local_deliver+0x18e/0x1f0 linux/net/ipv4/ip_input.c:254
 dst_input linux/./include/net/dst.h:461
 ip_rcv_finish linux/net/ipv4/ip_input.c:449
 NF_HOOK linux/./include/linux/netfilter.h:314
 NF_HOOK linux/./include/linux/netfilter.h:308
 ip_rcv+0x2c5/0x5d0 linux/net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core+0x199/0x1e0 linux/net/core/dev.c:5534
 __netif_receive_skb+0x1f/0x1c0 linux/net/core/dev.c:5648
 process_backlog+0x101/0x6b0 linux/net/core/dev.c:5976
 __napi_poll.constprop.0+0xba/0x550 linux/net/core/dev.c:6576
 napi_poll linux/net/core/dev.c:6645
 net_rx_action+0x95a/0xe90 linux/net/core/dev.c:6781
 __do_softirq+0x21f/0x8e7 linux/kernel/softirq.c:553
 do_softirq linux/kernel/softirq.c:454
 do_softirq+0xb2/0xf0 linux/kernel/softirq.c:441
 &lt;/IRQ&gt;
 &lt;TASK&gt;
 __local_bh_enable_ip+0x100/0x120 linux/kernel/softirq.c:381
 local_bh_enable linux/./include/linux/bottom_half.h:33
 rcu_read_unlock_bh linux/./include/linux/rcupdate.h:851
 __dev_queue_xmit+0x871/0x3ee0 linux/net/core/dev.c:4378
 dev_queue_xmit linux/./include/linux/netdevice.h:3169
 neigh_hh_output linux/./include/net/neighbour.h:526
 neigh_output linux/./include/net/neighbour.h:540
 ip_finish_output2+0x169f/0x2550 linux/net/ipv4/ip_output.c:235
 __ip_finish_output linux/net/ipv4/ip_output.c:313
 __ip_finish_output+0x49e/0x950 linux/net/ipv4/ip_output.c:295
 ip_finish_output+0x31/0x310 linux/net/ipv4/ip_output.c:323
 NF_HOOK_COND linux/./include/linux/netfilter.h:303
 ip_output+0x13b/0x2a0 linux/net/ipv4/ip_output.c:433
 dst_output linux/./include/net/dst.h:451
 ip_local_out linux/net/ipv4/ip_output.c:129
 ip_send_skb+0x3e5/0x560 linux/net/ipv4/ip_output.c:1492
 udp_send_skb+0x73f/0x1530 linux/net/ipv4/udp.c:963
 udp_sendmsg+0x1a36/0x2b40 linux/net/ipv4/udp.c:1250
 inet_sendmsg+0x105/0x140 linux/net/ipv4/af_inet.c:850
 sock_sendmsg_nosec linux/net/socket.c:730
 __sock_sendmsg linux/net/socket.c:745
 __sys_sendto+0x42c/0x4e0 linux/net/socket.c:2191
 __do_sys_sendto linux/net/socket.c:2203
 __se_sys_sendto linux/net/socket.c:2199
 __x64_sys_sendto+0xe0/0x1c0 linux/net/socket.c:2199
 do_syscall_x64 linux/arch/x86/entry/common.c:52
 do_syscall_64+0xd8/0x270 linux/arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77 linux/arch/x86/entry/entry_64.S:120
RIP: 0033:0x7f3434974f29
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 8b 0d 37 8f 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007fff9154f2b8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3434974f29
RDX: 00000000000032c8 RSI: 00007fff9154f300 RDI: 0000000000000003
RBP: 00007fff915532e0 R08: 00007fff91553360 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000212 R12: 000055ed86d261d0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 &lt;/TASK&gt;

In the critical scenario, either the relevant skb is freed or its
ownership is transferred into a frag_lists. In both cases, the cleanup
code must not free it again: we need to clear the skb reference earlier.

Fixes: 1149557d64c9 ("tipc: eliminate unnecessary linearization of incoming buffers")
Cc: stable@vger.kernel.org
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-23852
Acked-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/752f1ccf762223d109845365d07f55414058e5a3.1714484273.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
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