kernel/linux.git/net/mctp, branch v6.19.11

mctp: route: hold key->lock in mctp_flow_prepare_output()

2026-03-19T15:14:53+00:00

[ Upstream commit 7d86aa41c073c4e7eb75fd2e674f1fd8f289728a ] mctp_flow_prepare_output() checks key->dev and may call mctp_dev_set_key(), but it does not hold key->lock while doing so. mctp_dev_set_key() and mctp_dev_release_key() are annotated with __must_hold(&key->lock), so key->dev access is intended to be serialized by key->lock. The mctp_sendmsg() transmit path reaches mctp_flow_prepare_output() via mctp_local_output() -> mctp_dst_output() without holding key->lock, so the check-and-set sequence is racy. Example interleaving: CPU0 CPU1 ---- ---- mctp_flow_prepare_output(key, devA) if (!key->dev) // sees NULL mctp_flow_prepare_output( key, devB) if (!key->dev) // still NULL mctp_dev_set_key(devB, key) mctp_dev_hold(devB) key->dev = devB mctp_dev_set_key(devA, key) mctp_dev_hold(devA) key->dev = devA // overwrites devB Now both devA and devB references were acquired, but only the final key->dev value is tracked for release. One reference can be lost, causing a resource leak as mctp_dev_release_key() would only decrease the reference on one dev. Fix by taking key->lock around the key->dev check and mctp_dev_set_key() call. Fixes: 67737c457281 ("mctp: Pass flow data & flow release events to drivers") Signed-off-by: Chengfeng Ye Link: https://patch.msgid.link/20260306031402.857224-1-dg573847474@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: mctp: ensure our nlmsg responses are initialised

2026-02-26T23:01:29+00:00

[ Upstream commit a6a9bc544b675d8b5180f2718ec985ad267b5cbf ] Syed Faraz Abrar (@farazsth98) from Zellic, and Pumpkin (@u1f383) from DEVCORE Research Team working with Trend Micro Zero Day Initiative report that a RTM_GETNEIGH will return uninitalised data in the pad bytes of the ndmsg data. Ensure we're initialising the netlink data to zero, in the link, addr and neigh response messages. Fixes: 831119f88781 ("mctp: Add neighbour netlink interface") Fixes: 06d2f4c583a7 ("mctp: Add netlink route management") Fixes: 583be982d934 ("mctp: Add device handling and netlink interface") Signed-off-by: Jeremy Kerr Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260209-dev-mctp-nlmsg-v1-1-f1e30c346a43@codeconstruct.com.au Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: mctp: test: move TX packetqueue from dst to dev

2025-12-01T21:52:13+00:00

To capture TX packets during a test, we are currently intercepting the dst->output with an implementation that adds the transmitted packet to a skb queue attached to the test-specific mock dst. The netdev itself is not involved in the test TX path. Instead, we can just use our test device to stash TXed packets for later inspection by the test. This means we can include the actual mctp_dst_output() implementation in the test (by setting dst.output in the test case), and don't need to be creating fake dst objects, or their corresponding skb queues. We need to ensure that the netdev is up to allow delivery to ndo_start_xmit, but the tests assume active devices at present anyway. Signed-off-by: Jeremy Kerr Link: https://patch.msgid.link/20251126-dev-mctp-test-tx-queue-v2-1-4e5bbd1d6c57@codeconstruct.com.au Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-11-27T20:19:08+00:00

Conflicts: net/xdp/xsk.c 0ebc27a4c67d ("xsk: avoid data corruption on cq descriptor number") 8da7bea7db69 ("xsk: add indirect call for xsk_destruct_skb") 30ed05adca4a ("xsk: use a smaller new lock for shared pool case") https://lore.kernel.org/20251127105450.4a1665ec@canb.auug.org.au https://lore.kernel.org/eb4eee14-7e24-4d1b-b312-e9ea738fefee@kernel.org Signed-off-by: Jakub Kicinski

net: mctp: unconditionally set skb->dev on dst output

2025-11-27T10:39:12+00:00

On transmit, we are currently relying on skb->dev being set by mctp_local_output() when we first set up the skb destination fields. However, forwarded skbs do not use the local_output path, so will retain their incoming netdev as their ->dev on tx. This does not work when we're forwarding between interfaces. Set skb->dev unconditionally in the transmit path, to allow for proper forwarding. We keep the skb->dev initialisation in mctp_local_output(), as we use it for fragmentation. Fixes: 269936db5eb3 ("net: mctp: separate routing database from routing operations") Suggested-by: Vince Chang Signed-off-by: Jeremy Kerr Link: https://patch.msgid.link/20251125-dev-forward-v1-1-54ecffcd0616@codeconstruct.com.au Signed-off-by: Paolo Abeni

net: Convert proto_ops connect() callbacks to use sockaddr_unsized

2025-11-05T03:10:32+00:00

Update all struct proto_ops connect() callback function prototypes from "struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the compiler about object sizes. Calls into struct proto handlers gain casts that will be removed in the struct proto conversion patch. No binary changes expected. Signed-off-by: Kees Cook Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org Signed-off-by: Jakub Kicinski

net: Convert proto_ops bind() callbacks to use sockaddr_unsized

2025-11-05T03:10:32+00:00

Update all struct proto_ops bind() callback function prototypes from "struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the compiler about object sizes. Calls into struct proto handlers gain casts that will be removed in the struct proto conversion patch. No binary changes expected. Signed-off-by: Kees Cook Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org Signed-off-by: Jakub Kicinski

net: mctp: fix typo in comment

2025-09-09T00:47:57+00:00

Correct a typo in af_mctp.c: "fist" -> "first". Signed-off-by: Alok Tiwari Acked-by: Jeremy Kerr Link: https://patch.msgid.link/20250905165006.3032472-1-alok.a.tiwari@oracle.com Signed-off-by: Jakub Kicinski

mctp: return -ENOPROTOOPT for unknown getsockopt options

2025-09-04T00:01:52+00:00

In mctp_getsockopt(), unrecognized options currently return -EINVAL. In contrast, mctp_setsockopt() returns -ENOPROTOOPT for unknown options. Update mctp_getsockopt() to also return -ENOPROTOOPT for unknown options. This aligns the behavior of getsockopt() and setsockopt(), and matches the standard kernel socket API convention for handling unsupported options. Fixes: 99ce45d5e7db ("mctp: Implement extended addressing") Signed-off-by: Alok Tiwari Link: https://patch.msgid.link/20250902102059.1370008-1-alok.a.tiwari@oracle.com Signed-off-by: Jakub Kicinski

net: mctp: mctp_fraq_queue should take ownership of passed skb

2025-09-02T12:45:51+00:00

As of commit f5d83cf0eeb9 ("net: mctp: unshare packets when reassembling"), we skb_unshare() in mctp_frag_queue(). The unshare may invalidate the original skb pointer, so we need to treat the skb as entirely owned by the fraq queue, even on failure. Fixes: f5d83cf0eeb9 ("net: mctp: unshare packets when reassembling") Signed-off-by: Jeremy Kerr Link: https://patch.msgid.link/20250829-mctp-skb-unshare-v1-1-1c28fe10235a@codeconstruct.com.au Signed-off-by: Paolo Abeni