linux.git/net/core, branch v6.2 Linux kernel source tree devlink: Fix netdev notifier chain corruption 2023-02-16T10:53:47+00:00 Ido Schimmel idosch@nvidia.com 2023-02-15T07:31:39+00:00 b20b8aec6ffc07bb547966b356780cd344f20f5b Cited commit changed devlink to register its netdev notifier block on the global netdev notifier chain instead of on the per network namespace one. However, when changing the network namespace of the devlink instance, devlink still tries to unregister its notifier block from the chain of the old namespace and register it on the chain of the new namespace. This results in corruption of the notifier chains, as the same notifier block is registered on two different chains: The global one and the per network namespace one. In turn, this causes other problems such as the inability to dismantle namespaces due to netdev reference count issues. Fix by preventing devlink from moving its notifier block between namespaces. Reproducer: # echo "10 1" > /sys/bus/netdevsim/new_device # ip netns add test123 # devlink dev reload netdevsim/netdevsim10 netns test123 # ip netns del test123 [ 71.935619] unregister_netdevice: waiting for lo to become free. Usage count = 2 [ 71.938348] leaked reference. Fixes: 565b4824c39f ("devlink: change port event netdev notifier from per-net to global") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20230215073139.1360108-1-idosch@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Cited commit changed devlink to register its netdev notifier block on
the global netdev notifier chain instead of on the per network namespace
one.

However, when changing the network namespace of the devlink instance,
devlink still tries to unregister its notifier block from the chain of
the old namespace and register it on the chain of the new namespace.
This results in corruption of the notifier chains, as the same notifier
block is registered on two different chains: The global one and the per
network namespace one. In turn, this causes other problems such as the
inability to dismantle namespaces due to netdev reference count issues.

Fix by preventing devlink from moving its notifier block between
namespaces.

Reproducer:

 # echo "10 1" > /sys/bus/netdevsim/new_device
 # ip netns add test123
 # devlink dev reload netdevsim/netdevsim10 netns test123
 # ip netns del test123
 [   71.935619] unregister_netdevice: waiting for lo to become free. Usage count = 2
 [   71.938348] leaked reference.

Fixes: 565b4824c39f ("devlink: change port event netdev notifier from per-net to global")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230215073139.1360108-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: Fix unwanted sign extension in netdev_stats_to_stats64() 2023-02-13T09:53:25+00:00 Felix Riemann felix.riemann@sma.de 2023-02-10T12:36:44+00:00 9b55d3f0a69af649c62cbc2633e6d695bb3cc583 When converting net_device_stats to rtnl_link_stats64 sign extension is triggered on ILP32 machines as 6c1c509778 changed the previous "ulong -> u64" conversion to "long -> u64" by accessing the net_device_stats fields through a (signed) atomic_long_t. This causes for example the received bytes counter to jump to 16EiB after having received 2^31 bytes. Casting the atomic value to "unsigned long" beforehand converting it into u64 avoids this. Fixes: 6c1c5097781f ("net: add atomic_long_t to net_device_stats fields") Signed-off-by: Felix Riemann <felix.riemann@sma.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
When converting net_device_stats to rtnl_link_stats64 sign extension
is triggered on ILP32 machines as 6c1c509778 changed the previous
"ulong -> u64" conversion to "long -> u64" by accessing the
net_device_stats fields through a (signed) atomic_long_t.

This causes for example the received bytes counter to jump to 16EiB after
having received 2^31 bytes. Casting the atomic value to "unsigned long"
beforehand converting it into u64 avoids this.

Fixes: 6c1c5097781f ("net: add atomic_long_t to net_device_stats fields")
Signed-off-by: Felix Riemann <felix.riemann@sma.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Remove WARN_ON_ONCE(sk->sk_forward_alloc) from sk_stream_kill_queues(). 2023-02-11T03:53:42+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2023-02-10T00:22:02+00:00 62ec33b44e0f7168ff2886520fec6fb62d03b5a3 Christoph Paasch reported that commit b5fc29233d28 ("inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy().") started triggering WARN_ON_ONCE(sk->sk_forward_alloc) in sk_stream_kill_queues(). [0 - 2] Also, we can reproduce it by a program in [3]. In the commit, we delay freeing ipv6_pinfo.pktoptions from sk->destroy() to sk->sk_destruct(), so sk->sk_forward_alloc is no longer zero in inet_csk_destroy_sock(). The same check has been in inet_sock_destruct() from at least v2.6, we can just remove the WARN_ON_ONCE(). However, among the users of sk_stream_kill_queues(), only CAIF is not calling inet_sock_destruct(). Thus, we add the same WARN_ON_ONCE() to caif_sock_destructor(). [0]: https://lore.kernel.org/netdev/39725AB4-88F1-41B3-B07F-949C5CAEFF4F@icloud.com/ [1]: https://github.com/multipath-tcp/mptcp_net-next/issues/341 [2]: WARNING: CPU: 0 PID: 3232 at net/core/stream.c:212 sk_stream_kill_queues+0x2f9/0x3e0 Modules linked in: CPU: 0 PID: 3232 Comm: syz-executor.0 Not tainted 6.2.0-rc5ab24eb4698afbe147b424149c529e2a43ec24eb5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:sk_stream_kill_queues+0x2f9/0x3e0 Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e ec 00 00 00 8b ab 08 01 00 00 e9 60 ff ff ff e8 d0 5f b6 fe 0f 0b eb 97 e8 c7 5f b6 fe <0f> 0b eb a0 e8 be 5f b6 fe 0f 0b e9 6a fe ff ff e8 02 07 e3 fe e9 RSP: 0018:ffff88810570fc68 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888101f38f40 RSI: ffffffff8285e529 RDI: 0000000000000005 RBP: 0000000000000ce0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000ce0 R11: 0000000000000001 R12: ffff8881009e9488 R13: ffffffff84af2cc0 R14: 0000000000000000 R15: ffff8881009e9458 FS: 00007f7fdfbd5800(0000) GS:ffff88811b600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32923000 CR3: 00000001062fc006 CR4: 0000000000170ef0 Call Trace: <TASK> inet_csk_destroy_sock+0x1a1/0x320 __tcp_close+0xab6/0xe90 tcp_close+0x30/0xc0 inet_release+0xe9/0x1f0 inet6_release+0x4c/0x70 __sock_release+0xd2/0x280 sock_close+0x15/0x20 __fput+0x252/0xa20 task_work_run+0x169/0x250 exit_to_user_mode_prepare+0x113/0x120 syscall_exit_to_user_mode+0x1d/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f7fdf7ae28d Code: c1 20 00 00 75 10 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 37 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00000000007dfbb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f7fdf7ae28d RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000007f338e0f R09: 0000000000000e0f R10: 000000007f338e13 R11: 0000000000000293 R12: 00007f7fdefff000 R13: 00007f7fdefffcd8 R14: 00007f7fdefffce0 R15: 00007f7fdefffcd8 </TASK> [3]: https://lore.kernel.org/netdev/20230208004245.83497-1-kuniyu@amazon.com/ Fixes: b5fc29233d28 ("inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy().") Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Christoph Paasch <christophpaasch@icloud.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Christoph Paasch reported that commit b5fc29233d28 ("inet6: Remove
inet6_destroy_sock() in sk->sk_prot->destroy().") started triggering
WARN_ON_ONCE(sk->sk_forward_alloc) in sk_stream_kill_queues().  [0 - 2]
Also, we can reproduce it by a program in [3].

In the commit, we delay freeing ipv6_pinfo.pktoptions from sk->destroy()
to sk->sk_destruct(), so sk->sk_forward_alloc is no longer zero in
inet_csk_destroy_sock().

The same check has been in inet_sock_destruct() from at least v2.6,
we can just remove the WARN_ON_ONCE().  However, among the users of
sk_stream_kill_queues(), only CAIF is not calling inet_sock_destruct().
Thus, we add the same WARN_ON_ONCE() to caif_sock_destructor().

[0]: https://lore.kernel.org/netdev/39725AB4-88F1-41B3-B07F-949C5CAEFF4F@icloud.com/
[1]: https://github.com/multipath-tcp/mptcp_net-next/issues/341
[2]:
WARNING: CPU: 0 PID: 3232 at net/core/stream.c:212 sk_stream_kill_queues+0x2f9/0x3e0
Modules linked in:
CPU: 0 PID: 3232 Comm: syz-executor.0 Not tainted 6.2.0-rc5ab24eb4698afbe147b424149c529e2a43ec24eb5 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:sk_stream_kill_queues+0x2f9/0x3e0
Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e ec 00 00 00 8b ab 08 01 00 00 e9 60 ff ff ff e8 d0 5f b6 fe 0f 0b eb 97 e8 c7 5f b6 fe <0f> 0b eb a0 e8 be 5f b6 fe 0f 0b e9 6a fe ff ff e8 02 07 e3 fe e9
RSP: 0018:ffff88810570fc68 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888101f38f40 RSI: ffffffff8285e529 RDI: 0000000000000005
RBP: 0000000000000ce0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000ce0 R11: 0000000000000001 R12: ffff8881009e9488
R13: ffffffff84af2cc0 R14: 0000000000000000 R15: ffff8881009e9458
FS:  00007f7fdfbd5800(0000) GS:ffff88811b600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32923000 CR3: 00000001062fc006 CR4: 0000000000170ef0
Call Trace:
 <TASK>
 inet_csk_destroy_sock+0x1a1/0x320
 __tcp_close+0xab6/0xe90
 tcp_close+0x30/0xc0
 inet_release+0xe9/0x1f0
 inet6_release+0x4c/0x70
 __sock_release+0xd2/0x280
 sock_close+0x15/0x20
 __fput+0x252/0xa20
 task_work_run+0x169/0x250
 exit_to_user_mode_prepare+0x113/0x120
 syscall_exit_to_user_mode+0x1d/0x40
 do_syscall_64+0x48/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f7fdf7ae28d
Code: c1 20 00 00 75 10 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 37 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00000000007dfbb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f7fdf7ae28d
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000003
RBP: 0000000000000000 R08: 000000007f338e0f R09: 0000000000000e0f
R10: 000000007f338e13 R11: 0000000000000293 R12: 00007f7fdefff000
R13: 00007f7fdefffcd8 R14: 00007f7fdefffce0 R15: 00007f7fdefffcd8
 </TASK>

[3]: https://lore.kernel.org/netdev/20230208004245.83497-1-kuniyu@amazon.com/

Fixes: b5fc29233d28 ("inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy().")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Christoph Paasch <christophpaasch@icloud.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: initialize net->notrefcnt_tracker earlier 2023-02-10T06:49:25+00:00 Eric Dumazet edumazet@google.com 2023-02-08T18:21:23+00:00 6e77a5a4af05d5e7391c841a4a4f3e4cadf72c25 syzbot was able to trigger a warning [1] from net_free() calling ref_tracker_dir_exit(&net->notrefcnt_tracker) while the corresponding ref_tracker_dir_init() has not been done yet. copy_net_ns() can indeed bypass the call to setup_net() in some error conditions. Note: We might factorize/move more code in preinit_net() in the future. [1] INFO: trying to register non-static key. The code is fine but needs lockdep annotation, or maybe you didn't initialize this object before use? turning off the locking correctness validator. CPU: 0 PID: 5817 Comm: syz-executor.3 Not tainted 6.2.0-rc7-next-20230208-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 assign_lock_key kernel/locking/lockdep.c:982 [inline] register_lock_class+0xdb6/0x1120 kernel/locking/lockdep.c:1295 __lock_acquire+0x10a/0x5df0 kernel/locking/lockdep.c:4951 lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5691 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 ref_tracker_dir_exit+0x52/0x600 lib/ref_tracker.c:24 net_free net/core/net_namespace.c:442 [inline] net_free+0x98/0xd0 net/core/net_namespace.c:436 copy_net_ns+0x4f3/0x6b0 net/core/net_namespace.c:493 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x449/0x920 kernel/fork.c:3205 __do_sys_unshare kernel/fork.c:3276 [inline] __se_sys_unshare kernel/fork.c:3274 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3274 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 Fixes: 0cafd77dcd03 ("net: add a refcount tracker for kernel sockets") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230208182123.3821604-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
syzbot was able to trigger a warning [1] from net_free()
calling ref_tracker_dir_exit(&net->notrefcnt_tracker)
while the corresponding ref_tracker_dir_init() has not been
done yet.

copy_net_ns() can indeed bypass the call to setup_net()
in some error conditions.

Note:

We might factorize/move more code in preinit_net() in the future.

[1]
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 0 PID: 5817 Comm: syz-executor.3 Not tainted 6.2.0-rc7-next-20230208-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
assign_lock_key kernel/locking/lockdep.c:982 [inline]
register_lock_class+0xdb6/0x1120 kernel/locking/lockdep.c:1295
__lock_acquire+0x10a/0x5df0 kernel/locking/lockdep.c:4951
lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5691
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162
ref_tracker_dir_exit+0x52/0x600 lib/ref_tracker.c:24
net_free net/core/net_namespace.c:442 [inline]
net_free+0x98/0xd0 net/core/net_namespace.c:436
copy_net_ns+0x4f3/0x6b0 net/core/net_namespace.c:493
create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228
ksys_unshare+0x449/0x920 kernel/fork.c:3205
__do_sys_unshare kernel/fork.c:3276 [inline]
__se_sys_unshare kernel/fork.c:3274 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3274
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80

Fixes: 0cafd77dcd03 ("net: add a refcount tracker for kernel sockets")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230208182123.3821604-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
txhash: fix sk->sk_txrehash default 2023-02-08T09:07:11+00:00 Kevin Yang yyd@google.com 2023-02-07T02:08:20+00:00 c11204c78d6966c5bda6dd05c3ac5cbb193f93e3 This code fix a bug that sk->sk_txrehash gets its default enable value from sysctl_txrehash only when the socket is a TCP listener. We should have sysctl_txrehash to set the default sk->sk_txrehash, no matter TCP, nor listerner/connector. Tested by following packetdrill: 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 socket(..., SOCK_DGRAM, IPPROTO_UDP) = 4 // SO_TXREHASH == 74, default to sysctl_txrehash == 1 +0 getsockopt(3, SOL_SOCKET, 74, [1], [4]) = 0 +0 getsockopt(4, SOL_SOCKET, 74, [1], [4]) = 0 Fixes: 26859240e4ee ("txhash: Add socket option to control TX hash rethink behavior") Signed-off-by: Kevin Yang <yyd@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
This code fix a bug that sk->sk_txrehash gets its default enable
value from sysctl_txrehash only when the socket is a TCP listener.

We should have sysctl_txrehash to set the default sk->sk_txrehash,
no matter TCP, nor listerner/connector.

Tested by following packetdrill:
  0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
  +0 socket(..., SOCK_DGRAM, IPPROTO_UDP) = 4
  // SO_TXREHASH == 74, default to sysctl_txrehash == 1
  +0 getsockopt(3, SOL_SOCKET, 74, [1], [4]) = 0
  +0 getsockopt(4, SOL_SOCKET, 74, [1], [4]) = 0

Fixes: 26859240e4ee ("txhash: Add socket option to control TX hash rethink behavior")
Signed-off-by: Kevin Yang <yyd@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
devlink: change port event netdev notifier from per-net to global 2023-02-07T13:13:55+00:00 Jiri Pirko jiri@nvidia.com 2023-02-06T09:41:51+00:00 565b4824c39fa335cba2028a09d7beb7112f3c9a Currently only the network namespace of devlink instance is monitored for port events. If netdev is moved to a different namespace and then unregistered, NETDEV_PRE_UNINIT is missed which leads to trigger following WARN_ON in devl_port_unregister(). WARN_ON(devlink_port->type != DEVLINK_PORT_TYPE_NOTSET); Fix this by changing the netdev notifier from per-net to global so no event is missed. Fixes: 02a68a47eade ("net: devlink: track netdev with devlink_port assigned") Signed-off-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Link: https://lore.kernel.org/r/20230206094151.2557264-1-jiri@resnulli.us Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Currently only the network namespace of devlink instance is monitored
for port events. If netdev is moved to a different namespace and then
unregistered, NETDEV_PRE_UNINIT is missed which leads to trigger
following WARN_ON in devl_port_unregister().
WARN_ON(devlink_port->type != DEVLINK_PORT_TYPE_NOTSET);

Fix this by changing the netdev notifier from per-net to global so no
event is missed.

Fixes: 02a68a47eade ("net: devlink: track netdev with devlink_port assigned")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230206094151.2557264-1-jiri@resnulli.us
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
neigh: make sure used and confirmed times are valid 2023-02-06T08:44:31+00:00 Julian Anastasov ja@ssi.bg 2023-02-02T15:25:51+00:00 c1d2ecdf5e38e3489ce8328238b558b3b2866fe1 Entries can linger in cache without timer for days, thanks to the gc_thresh1 limit. As result, without traffic, the confirmed time can be outdated and to appear to be in the future. Later, on traffic, NUD_STALE entries can switch to NUD_DELAY and start the timer which can see the invalid confirmed time and wrongly switch to NUD_REACHABLE state instead of NUD_PROBE. As result, timer is set many days in the future. This is more visible on 32-bit platforms, with higher HZ value. Why this is a problem? While we expect unused entries to expire, such entries stay in REACHABLE state for too long, locked in cache. They are not expired normally, only when cache is full. Problem and the wrong state change reported by Zhang Changzhong: 172.16.1.18 dev bond0 lladdr 0a:0e:0f:01:12:01 ref 1 used 350521/15994171/350520 probes 4 REACHABLE 350520 seconds have elapsed since this entry was last updated, but it is still in the REACHABLE state (base_reachable_time_ms is 30000), preventing lladdr from being updated through probe. Fix it by ensuring timer is started with valid used/confirmed times. Considering the valid time range is LONG_MAX jiffies, we try not to go too much in the past while we are in DELAY/PROBE state. There are also places that need used/updated times to be validated while timer is not running. Reported-by: Zhang Changzhong <zhangchangzhong@huawei.com> Signed-off-by: Julian Anastasov <ja@ssi.bg> Tested-by: Zhang Changzhong <zhangchangzhong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Entries can linger in cache without timer for days, thanks to
the gc_thresh1 limit. As result, without traffic, the confirmed
time can be outdated and to appear to be in the future. Later,
on traffic, NUD_STALE entries can switch to NUD_DELAY and start
the timer which can see the invalid confirmed time and wrongly
switch to NUD_REACHABLE state instead of NUD_PROBE. As result,
timer is set many days in the future. This is more visible on
32-bit platforms, with higher HZ value.

Why this is a problem? While we expect unused entries to expire,
such entries stay in REACHABLE state for too long, locked in
cache. They are not expired normally, only when cache is full.

Problem and the wrong state change reported by Zhang Changzhong:

172.16.1.18 dev bond0 lladdr 0a:0e:0f:01:12:01 ref 1 used 350521/15994171/350520 probes 4 REACHABLE

350520 seconds have elapsed since this entry was last updated, but it is
still in the REACHABLE state (base_reachable_time_ms is 30000),
preventing lladdr from being updated through probe.

Fix it by ensuring timer is started with valid used/confirmed
times. Considering the valid time range is LONG_MAX jiffies,
we try not to go too much in the past while we are in
DELAY/PROBE state. There are also places that need
used/updated times to be validated while timer is not running.

Reported-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Tested-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: fix NULL pointer in skb_segment_list 2023-02-01T05:07:04+00:00 Yan Zhai yan@cloudflare.com 2023-01-30T20:51:48+00:00 876e8ca8366735a604bac86ff7e2732fc9d85d2d Commit 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.") introduced UDP listifyed GRO. The segmentation relies on frag_list being untouched when passing through the network stack. This assumption can be broken sometimes, where frag_list itself gets pulled into linear area, leaving frag_list being NULL. When this happens it can trigger following NULL pointer dereference, and panic the kernel. Reverse the test condition should fix it. [19185.577801][ C1] BUG: kernel NULL pointer dereference, address: ... [19185.663775][ C1] RIP: 0010:skb_segment_list+0x1cc/0x390 ... [19185.834644][ C1] Call Trace: [19185.841730][ C1] <TASK> [19185.848563][ C1] __udp_gso_segment+0x33e/0x510 [19185.857370][ C1] inet_gso_segment+0x15b/0x3e0 [19185.866059][ C1] skb_mac_gso_segment+0x97/0x110 [19185.874939][ C1] __skb_gso_segment+0xb2/0x160 [19185.883646][ C1] udp_queue_rcv_skb+0xc3/0x1d0 [19185.892319][ C1] udp_unicast_rcv_skb+0x75/0x90 [19185.900979][ C1] ip_protocol_deliver_rcu+0xd2/0x200 [19185.910003][ C1] ip_local_deliver_finish+0x44/0x60 [19185.918757][ C1] __netif_receive_skb_one_core+0x8b/0xa0 [19185.927834][ C1] process_backlog+0x88/0x130 [19185.935840][ C1] __napi_poll+0x27/0x150 [19185.943447][ C1] net_rx_action+0x27e/0x5f0 [19185.951331][ C1] ? mlx5_cq_tasklet_cb+0x70/0x160 [mlx5_core] [19185.960848][ C1] __do_softirq+0xbc/0x25d [19185.968607][ C1] irq_exit_rcu+0x83/0xb0 [19185.976247][ C1] common_interrupt+0x43/0xa0 [19185.984235][ C1] asm_common_interrupt+0x22/0x40 ... [19186.094106][ C1] </TASK> Fixes: 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.") Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/Y9gt5EUizK1UImEP@debian Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Commit 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.")
introduced UDP listifyed GRO. The segmentation relies on frag_list being
untouched when passing through the network stack. This assumption can be
broken sometimes, where frag_list itself gets pulled into linear area,
leaving frag_list being NULL. When this happens it can trigger
following NULL pointer dereference, and panic the kernel. Reverse the
test condition should fix it.

[19185.577801][    C1] BUG: kernel NULL pointer dereference, address:
...
[19185.663775][    C1] RIP: 0010:skb_segment_list+0x1cc/0x390
...
[19185.834644][    C1] Call Trace:
[19185.841730][    C1]  <TASK>
[19185.848563][    C1]  __udp_gso_segment+0x33e/0x510
[19185.857370][    C1]  inet_gso_segment+0x15b/0x3e0
[19185.866059][    C1]  skb_mac_gso_segment+0x97/0x110
[19185.874939][    C1]  __skb_gso_segment+0xb2/0x160
[19185.883646][    C1]  udp_queue_rcv_skb+0xc3/0x1d0
[19185.892319][    C1]  udp_unicast_rcv_skb+0x75/0x90
[19185.900979][    C1]  ip_protocol_deliver_rcu+0xd2/0x200
[19185.910003][    C1]  ip_local_deliver_finish+0x44/0x60
[19185.918757][    C1]  __netif_receive_skb_one_core+0x8b/0xa0
[19185.927834][    C1]  process_backlog+0x88/0x130
[19185.935840][    C1]  __napi_poll+0x27/0x150
[19185.943447][    C1]  net_rx_action+0x27e/0x5f0
[19185.951331][    C1]  ? mlx5_cq_tasklet_cb+0x70/0x160 [mlx5_core]
[19185.960848][    C1]  __do_softirq+0xbc/0x25d
[19185.968607][    C1]  irq_exit_rcu+0x83/0xb0
[19185.976247][    C1]  common_interrupt+0x43/0xa0
[19185.984235][    C1]  asm_common_interrupt+0x22/0x40
...
[19186.094106][    C1]  </TASK>

Fixes: 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.")
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/Y9gt5EUizK1UImEP@debian
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2023-01-28T07:32:03+00:00 Jakub Kicinski kuba@kernel.org 2023-01-28T07:32:02+00:00 0548c5f26a0fefa721b29be2bfff1c44f15b6d73 Daniel Borkmann says: ==================== bpf 2023-01-27 We've added 10 non-merge commits during the last 9 day(s) which contain a total of 10 files changed, 170 insertions(+), 59 deletions(-). The main changes are: 1) Fix preservation of register's parent/live fields when copying range-info, from Eduard Zingerman. 2) Fix an off-by-one bug in bpf_mem_cache_idx() to select the right cache, from Hou Tao. 3) Fix stack overflow from infinite recursion in sock_map_close(), from Jakub Sitnicki. 4) Fix missing btf_put() in register_btf_id_dtor_kfuncs()'s error path, from Jiri Olsa. 5) Fix a splat from bpf_setsockopt() via lsm_cgroup/socket_sock_rcv_skb, from Kui-Feng Lee. 6) Fix bpf_send_signal[_thread]() helpers to hold a reference on the task, from Yonghong Song. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Fix the kernel crash caused by bpf_setsockopt(). selftests/bpf: Cover listener cloning with progs attached to sockmap selftests/bpf: Pass BPF skeleton to sockmap_listen ops tests bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener bpf, sockmap: Don't let sock_map_{close,destroy,unhash} call itself bpf: Add missing btf_put to register_btf_id_dtor_kfuncs selftests/bpf: Verify copy_register_state() preserves parent/live fields bpf: Fix to preserve reg parent/live fields when copying range info bpf: Fix a possible task gone issue with bpf_send_signal[_thread]() helpers bpf: Fix off-by-one error in bpf_mem_cache_idx() ==================== Link: https://lore.kernel.org/r/20230127215820.4993-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Daniel Borkmann says:

====================
bpf 2023-01-27

We've added 10 non-merge commits during the last 9 day(s) which contain
a total of 10 files changed, 170 insertions(+), 59 deletions(-).

The main changes are:

1) Fix preservation of register's parent/live fields when copying
   range-info, from Eduard Zingerman.

2) Fix an off-by-one bug in bpf_mem_cache_idx() to select the right
   cache, from Hou Tao.

3) Fix stack overflow from infinite recursion in sock_map_close(),
   from Jakub Sitnicki.

4) Fix missing btf_put() in register_btf_id_dtor_kfuncs()'s error path,
   from Jiri Olsa.

5) Fix a splat from bpf_setsockopt() via lsm_cgroup/socket_sock_rcv_skb,
   from Kui-Feng Lee.

6) Fix bpf_send_signal[_thread]() helpers to hold a reference on the task,
   from Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Fix the kernel crash caused by bpf_setsockopt().
  selftests/bpf: Cover listener cloning with progs attached to sockmap
  selftests/bpf: Pass BPF skeleton to sockmap_listen ops tests
  bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener
  bpf, sockmap: Don't let sock_map_{close,destroy,unhash} call itself
  bpf: Add missing btf_put to register_btf_id_dtor_kfuncs
  selftests/bpf: Verify copy_register_state() preserves parent/live fields
  bpf: Fix to preserve reg parent/live fields when copying range info
  bpf: Fix a possible task gone issue with bpf_send_signal[_thread]() helpers
  bpf: Fix off-by-one error in bpf_mem_cache_idx()
====================

Link: https://lore.kernel.org/r/20230127215820.4993-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
skb: Do mix page pool and page referenced frags in GRO 2023-01-28T07:21:27+00:00 Alexander Duyck alexanderduyck@fb.com 2023-01-26T19:06:59+00:00 7d2c89b325874a35564db5630a459966afab04cc GSO should not merge page pool recycled frames with standard reference counted frames. Traditionally this didn't occur, at least not often. However as we start looking at adding support for wireless adapters there becomes the potential to mix the two due to A-MSDU repartitioning frames in the receive path. There are possibly other places where this may have occurred however I suspect they must be few and far between as we have not seen this issue until now. Fixes: 53e0961da1c7 ("page_pool: add frag page recycling support in page pool") Reported-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/167475990764.1934330.11960904198087757911.stgit@localhost.localdomain Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
GSO should not merge page pool recycled frames with standard reference
counted frames. Traditionally this didn't occur, at least not often.
However as we start looking at adding support for wireless adapters there
becomes the potential to mix the two due to A-MSDU repartitioning frames in
the receive path. There are possibly other places where this may have
occurred however I suspect they must be few and far between as we have not
seen this issue until now.

Fixes: 53e0961da1c7 ("page_pool: add frag page recycling support in page pool")
Reported-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Alexander Duyck <alexanderduyck@fb.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/167475990764.1934330.11960904198087757911.stgit@localhost.localdomain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>