kernel/linux.git/drivers/net/netdevsim, branch v6.19.11

netdevsim: drop PSP ext ref on forward failure

2026-03-25T10:13:28+00:00

[ Upstream commit 7d9351435ebba08bbb60f42793175c9dc714d2fb ] nsim_do_psp() takes an extra reference to the PSP skb extension so the extension survives __dev_forward_skb(). That forward path scrubs the skb and drops attached skb extensions before nsim_psp_handle_ext() can reattach the PSP metadata. If __dev_forward_skb() fails in nsim_forward_skb(), the function returns before nsim_psp_handle_ext() can attach that extension to the skb, leaving the extra reference leaked. Drop the saved PSP extension reference before returning from the forward-failure path. Guard the put because plain or non-decapsulated traffic can also fail forwarding without ever taking the extra PSP reference. Fixes: f857478d6206 ("netdevsim: a basic test PSP implementation") Signed-off-by: Wesley Atwell Reviewed-by: Daniel Zahka Link: https://patch.msgid.link/20260317061431.1482716-1-atwellwea@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

netdevsim: fix a race issue related to the operation on bpf_bound_progs list

2026-01-20T16:18:52+00:00

The netdevsim driver lacks a protection mechanism for operations on the bpf_bound_progs list. When the nsim_bpf_create_prog() performs list_add_tail, it is possible that nsim_bpf_destroy_prog() is simultaneously performs list_del. Concurrent operations on the list may lead to list corruption and trigger a kernel crash as follows: [ 417.290971] kernel BUG at lib/list_debug.c:62! [ 417.290983] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 417.290992] CPU: 10 PID: 168 Comm: kworker/10:1 Kdump: loaded Not tainted 6.19.0-rc5 #1 [ 417.291003] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 417.291007] Workqueue: events bpf_prog_free_deferred [ 417.291021] RIP: 0010:__list_del_entry_valid_or_report+0xa7/0xc0 [ 417.291034] Code: a8 ff 0f 0b 48 89 fe 48 89 ca 48 c7 c7 48 a1 eb ae e8 ed fb a8 ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 80 a1 eb ae e8 d9 fb a8 ff <0f> 0b 48 89 d1 48 c7 c7 d0 a1 eb ae 48 89 f2 48 89 c6 e8 c2 fb a8 [ 417.291040] RSP: 0018:ffffb16a40807df8 EFLAGS: 00010246 [ 417.291046] RAX: 000000000000006d RBX: ffff8e589866f500 RCX: 0000000000000000 [ 417.291051] RDX: 0000000000000000 RSI: ffff8e59f7b23180 RDI: ffff8e59f7b23180 [ 417.291055] RBP: ffffb16a412c9000 R08: 0000000000000000 R09: 0000000000000003 [ 417.291059] R10: ffffb16a40807c80 R11: ffffffffaf9edce8 R12: ffff8e594427ac20 [ 417.291063] R13: ffff8e59f7b44780 R14: ffff8e58800b7a05 R15: 0000000000000000 [ 417.291074] FS: 0000000000000000(0000) GS:ffff8e59f7b00000(0000) knlGS:0000000000000000 [ 417.291079] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 417.291083] CR2: 00007fc4083efe08 CR3: 00000001c3626006 CR4: 0000000000770ee0 [ 417.291088] PKRU: 55555554 [ 417.291091] Call Trace: [ 417.291096] [ 417.291103] nsim_bpf_destroy_prog+0x31/0x80 [netdevsim] [ 417.291154] __bpf_prog_offload_destroy+0x2a/0x80 [ 417.291163] bpf_prog_dev_bound_destroy+0x6f/0xb0 [ 417.291171] bpf_prog_free_deferred+0x18e/0x1a0 [ 417.291178] process_one_work+0x18a/0x3a0 [ 417.291188] worker_thread+0x27b/0x3a0 [ 417.291197] ? __pfx_worker_thread+0x10/0x10 [ 417.291207] kthread+0xe5/0x120 [ 417.291214] ? __pfx_kthread+0x10/0x10 [ 417.291221] ret_from_fork+0x31/0x50 [ 417.291230] ? __pfx_kthread+0x10/0x10 [ 417.291236] ret_from_fork_asm+0x1a/0x30 [ 417.291246] Add a mutex lock, to prevent simultaneous addition and deletion operations on the list. Fixes: 31d3ad832948 ("netdevsim: add bpf offload support") Reported-by: Yinhao Hu Reported-by: Kaiyan Mei Signed-off-by: Yun Lu Link: https://patch.msgid.link/20260116095308.11441-1-luyun_611@163.com Signed-off-by: Paolo Abeni

net: netdevsim: fix inconsistent carrier state after link/unlink

2026-01-07T02:04:00+00:00

This patch fixes the edge case behavior on ifup/ifdown and linking/unlinking two netdevsim interfaces: 1. unlink two interfaces netdevsim1 and netdevsim2 2. ifdown netdevsim1 3. ifup netdevsim1 4. link two interfaces netdevsim1 and netdevsim2 5. (Now two interfaces are linked in terms of netdevsim peer, but carrier state of the two interfaces remains DOWN.) This inconsistent behavior is caused by the current implementation, which only cares about the "link, then ifup" order, not "ifup, then link" order. This patch fixes the inconsistency by calling netif_carrier_on() when two netdevsim interfaces are linked. This patch fixes buggy behavior on NetworkManager-based systems which causes the netdevsim test to fail with the following error: # timeout set to 600 # selftests: drivers/net/netdevsim: peer.sh # 2025/12/25 00:54:03 socat[9115] W address is opened in read-write mode but only supports read-only # 2025/12/25 00:56:17 socat[9115] W connect(7, AF=2 192.168.1.1:1234, 16): Connection timed out # 2025/12/25 00:56:17 socat[9115] E TCP:192.168.1.1:1234: Connection timed out # expected 3 bytes, got 0 # 2025/12/25 00:56:17 socat[9109] W exiting on signal 15 not ok 13 selftests: drivers/net/netdevsim: peer.sh # exit=1 This patch also solves timeout on TCP Fast Open (TFO) test in NetworkManager-based systems because it also depends on netdevsim's carrier consistency. Fixes: 1a8fed52f7be ("netdevsim: set the carrier when the device goes up") Signed-off-by: Yohei Kojima Reviewed-by: Breno Leitao Link: https://patch.msgid.link/602c9e1ba5bb2ee1997bb38b1d866c9c3b807ae9.1767624906.git.yk@y-koj.net Signed-off-by: Jakub Kicinski

netdevsim: register a new devlink param with default value interface

2025-11-21T03:01:23+00:00

Create a new devlink param, test2, that supports default param actions via the devlink_param::get_default() and devlink_param::reset_default() functions. Reviewed-by: Aleksandr Loktionov Signed-off-by: Daniel Zahka Link: https://patch.msgid.link/20251119025038.651131-6-daniel.zahka@gmail.com Signed-off-by: Jakub Kicinski

netdevsim: add loopback support

2025-11-21T02:19:30+00:00

Support device loopback. Apparently this mode has been historically supported by the toeplitz test and I don't have any HW which lets me test the conversion.. Reviewed-by: Petr Machata Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20251120021024.2944527-12-kuba@kernel.org Signed-off-by: Jakub Kicinski

netdevsim: pass packets thru GRO on Rx

2025-11-21T02:19:30+00:00

To replace veth in software GRO testing with netdevsim we need GRO support in netdevsim. Luckily we already have NAPI support so this change is trivial (compared to veth). Reviewed-by: Petr Machata Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20251120021024.2944527-9-kuba@kernel.org Signed-off-by: Jakub Kicinski

netdevsim: implement psp device stats

2025-11-08T02:53:57+00:00

For now only tx/rx packets/bytes are reported. This is not compliant with the PSP Architecture Specification. Signed-off-by: Daniel Zahka Link: https://patch.msgid.link/20251106002608.1578518-6-daniel.zahka@gmail.com Signed-off-by: Jakub Kicinski

netdevsim: add ipsec hw_features

2025-10-16T22:44:32+00:00

Currently, netdevsim only sets dev->features, which makes the ESP features fixed. For example: # ethtool -k eni0np1 | grep esp tx-esp-segmentation: on [fixed] esp-hw-offload: on [fixed] esp-tx-csum-hw-offload: on [fixed] This patch adds the ESP features to hw_features, allowing them to be changed manually. For example: # ethtool -k eni0np1 | grep esp tx-esp-segmentation: on esp-hw-offload: on esp-tx-csum-hw-offload: on Suggested-by: Sabrina Dubroca Signed-off-by: Hangbin Liu Reviewed-by: Sabrina Dubroca Link: https://patch.msgid.link/20251015083649.54744-1-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski

netdevsim: set the carrier when the device goes up

2025-10-16T00:43:17+00:00

Bringing a linked netdevsim device down and then up causes communication failure because both interfaces lack carrier. Basically a ifdown/ifup on the interface make the link broken. Commit 3762ec05a9fbda ("netdevsim: add NAPI support") added supported for NAPI, calling netif_carrier_off() in nsim_stop(). This patch re-enables the carrier symmetrically on nsim_open(), in case the device is linked and the peer is up. Signed-off-by: Breno Leitao Fixes: 3762ec05a9fbda ("netdevsim: add NAPI support") Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/20251014-netdevsim_fix-v2-1-53b40590dae1@debian.org Signed-off-by: Jakub Kicinski

netdevsim: a basic test PSP implementation

2025-09-30T13:17:21+00:00

Provide a PSP implementation for netdevsim. Use psp_dev_encapsulate() and psp_dev_rcv() to do actual encapsulation and decapsulation on skbs, but perform no encryption or decryption. In order to make encryption with a bad key result in a drop on the peer's rx side, we stash our psd's generation number in the first byte of each key before handing to the peer. Signed-off-by: Jakub Kicinski Co-developed-by: Daniel Zahka Signed-off-by: Daniel Zahka Link: https://patch.msgid.link/20250927225420.1443468-2-kuba@kernel.org Reviewed-by: Willem de Bruijn Signed-off-by: Paolo Abeni