kernel/linux.git/drivers/net/netdevsim/netdev.c, branch v7.0-rc7

netdevsim: drop PSP ext ref on forward failure

2026-03-19T00:13:34+00:00

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

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

net: add bare bone queue configs

2026-01-14T02:13:36+00:00

We'll need to pass extra parameters when allocating a queue for memory providers. Define a new structure for queue configurations, and pass it to qapi callbacks. It's empty for now, actual parameters will be added in following patches. Configurations should persist across resets, and for that they're default-initialised on device registration and stored in struct netdev_rx_queue. We also add a new qapi callback for defaulting a given config. It must be implemented if a driver wants to use queue configs and is optional otherwise. Suggested-by: Jakub Kicinski Signed-off-by: Pavel Begunkov

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: 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

netdevsim: Fix wild pointer access in nsim_queue_free().

2025-08-14T00:26:39+00:00

syzbot reported the splat below. [0] When nsim_queue_uninit() is called from nsim_init_netdevsim(), register_netdevice() has not been called, thus dev->dstats has not been allocated. Let's not call dev_dstats_rx_dropped_add() in such a case. [0] BUG: unable to handle page fault for address: ffff88809782c020 PF: supervisor write access in kernel mode PF: error_code(0x0002) - not-present page PGD 1b401067 P4D 1b401067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN NOPTI CPU: 3 UID: 0 PID: 8476 Comm: syz.1.251 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #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 RIP: 0010:local_add arch/x86/include/asm/local.h:33 [inline] RIP: 0010:u64_stats_add include/linux/u64_stats_sync.h:89 [inline] RIP: 0010:dev_dstats_rx_dropped_add include/linux/netdevice.h:3027 [inline] RIP: 0010:nsim_queue_free+0xba/0x120 drivers/net/netdevsim/netdev.c:714 Code: 07 77 6c 4a 8d 3c ed 20 7e f1 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 46 4a 03 1c ed 20 7e f1 8d <4c> 01 63 20 be 00 02 00 00 48 8d 3d 00 00 00 00 e8 61 2f 58 fa 48 RSP: 0018:ffffc900044af150 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: ffff88809782c000 RCX: 00000000000079c3 RDX: 1ffffffff1be2fc7 RSI: ffffffff8c15f380 RDI: ffffffff8df17e38 RBP: ffff88805f59d000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000003 R14: ffff88806ceb3d00 R15: ffffed100dfd308e FS: 0000000000000000(0000) GS:ffff88809782c000(0063) knlGS:00000000f505db40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: ffff88809782c020 CR3: 000000006fc6a000 CR4: 0000000000352ef0 Call Trace: nsim_queue_uninit drivers/net/netdevsim/netdev.c:993 [inline] nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline] nsim_create+0xd0a/0x1260 drivers/net/netdevsim/netdev.c:1101 __nsim_dev_port_add+0x435/0x7d0 drivers/net/netdevsim/dev.c:1438 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1494 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline] nsim_dev_reload_up+0x5b8/0x860 drivers/net/netdevsim/dev.c:1003 devlink_reload+0x322/0x7c0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xe31/0x1410 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x206/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf708e579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f505d55c EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 0000000080000080 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: CR2: ffff88809782c020 Fixes: 2a68a22304f9 ("netdevsim: account dropped packet length in stats on queue free") Reported-by: syzbot+8aa80c6232008f7b957d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/688bb9ca.a00a0220.26d0e1.0050.GAE@google.com/ Suggested-by: Jakub Kicinski Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250812162130.4129322-1-kuniyu@google.com Signed-off-by: Jakub Kicinski

netdevsim: access ->pp through netmem_desc instead of page

2025-07-24T00:46:54+00:00

To eliminate the use of struct page in page pool, the page pool users should use netmem descriptor and APIs instead. Make netdevsim access ->pp through netmem_desc instead of page. Signed-off-by: Byungchul Park Link: https://patch.msgid.link/20250721021835.63939-5-byungchul@sk.com Signed-off-by: Jakub Kicinski

net: netdevsim: hook in XDP handling

2025-07-23T01:15:53+00:00

Add basic XDP support by hooking in do_xdp_generic(). This should be enough to validate most basic XDP tests. Signed-off-by: Mohsin Bashir Link: https://patch.msgid.link/20250719083059.3209169-2-mohsin.bashr@gmail.com Signed-off-by: Jakub Kicinski