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2026-04-20net: mctp: fix don't require received header reserved bits to be zeroYuan Zhaoming1-2/+6
From the MCTP Base specification (DSP0236 v1.2.1), the first byte of the MCTP header contains a 4 bit reserved field, and 4 bit version. On our current receive path, we require those 4 reserved bits to be zero, but the 9500-8i card is non-conformant, and may set these reserved bits. DSP0236 states that the reserved bits must be written as zero, and ignored when read. While the device might not conform to the former, we should accept these message to conform to the latter. Relax our check on the MCTP version byte to allow non-zero bits in the reserved field. Fixes: 889b7da23abf ("mctp: Add initial routing framework") Signed-off-by: Yuan Zhaoming <yuanzm2@lenovo.com> Cc: stable@vger.kernel.org Acked-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20260417141340.5306-1-yuanzhaoming901030@126.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-06net: mctp: defer creation of dst after source-address checkJeremy Kerr1-11/+11
Sashiko reports: > mctp_dst_from_route() increments the device reference count by calling > mctp_dev_hold(). When a valid route is found and dst is NULL, the > structure copy is bypassed and rc is set to 0. Instead of optimistically creating a dst from the final route (then releasing it if the saddr is invalid), perform the saddr check first. This means we don't have an unuecessary hold/release on the dev, which could leak if the dst pointer is NULL. No caller passes a NULL dst at present though (so the leak is not possible), but this is an intended use of mctp_dst_from_route(). Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260403-dev-mctp-dst-defer-v1-1-9c2c55faf9e9@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-02net: mctp: don't require a route for null-EID ingressJeremy Kerr1-19/+12
Currently, if we receive a physically-addressed packet for the local stack, we perform a route_lookup_null to find a matching device-based route. If a route is present, it will always have the ->output fn set to mctp_dst_input, which provides our delivery mechanism. However, if we don't yet have any local addresses assigned, we won't have any local routes to lookup, so this will fail. One of the use-cases for physical addressing is initial address assignment on endpoint nodes, where we would have no addresses, and therefore no local routes. Instead of iterating routes (looking for one matching the dev), just create a suitable mctp_dst for the device directly. Add a testcase for the no-route case too. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20260331-dev-mctp-null-eids-v1-3-b4d047372eaf@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-02net: mctp: allow local TX with no address assignedJeremy Kerr1-14/+4
If we're operating as a non-bus-owner endpoint, we may want to perform MCTP communication to get an address assigned. In this case, we'll have no local addresses, but can TX just fine either with extended routing, or where a direct route exists. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20260331-dev-mctp-null-eids-v1-2-b4d047372eaf@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-02net: mctp: perform source address lookups when we populate our dstJeremy Kerr1-19/+32
Rather than querying the output device for its address in mctp_local_output, set up the source address when we're populating the dst structure. If no address is assigned, use MCTP_ADDR_NULL. This will allow us more flexibility when routing for NULL-source-eid cases. For now though, we still reject a NULL source address in the output path. We need to update the tests a little, so that addresses are assigned before we do the dst lookups. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20260331-dev-mctp-null-eids-v1-1-b4d047372eaf@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-03-26net: mctp: avoid copy in fragmentation loop for near-MTU messagesJeremy Kerr1-15/+11
Currently, we incorrectly send messages that are within 4 bytes (a struct mctp_hdr) smaller than the MTU through mctp_do_fragment_route(). This has no effect on the actual fragmentation, as we will still send as one packet, but unnecessarily copies the original skb into a new single-fragment skb. Instead of having the MTU comparisons in both mctp_local_output() and mctp_do_fragment_route(), feed all local messages through the latter, and add the single-packet optimisation there. This means we can coalesce the routing path of mctp_local_output, so our out_release path is now solely for errors, so rename the label accordingly. Include a check in the route tests for the single-packet case too. Reported-by: yuanzhaoming <yuanzm2@lenovo.com> Closes: https://github.com/openbmc/linux/commit/269936db5eb3962fe290b1dc4dbf1859cd5a04dd#r175836230 Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260324-dev-mtu-copy-v1-1-7af6bd7027d3@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-10mctp: route: hold key->lock in mctp_flow_prepare_output()Chengfeng Ye1-4/+7
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 <dg573847474@gmail.com> Link: https://patch.msgid.link/20260306031402.857224-1-dg573847474@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds1-1/+1
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook1-2/+2
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 <kees@kernel.org>
2026-02-12net: mctp: ensure our nlmsg responses are initialisedJeremy Kerr1-0/+1
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 <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260209-dev-mctp-nlmsg-v1-1-f1e30c346a43@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-27net: mctp: unconditionally set skb->dev on dst outputJeremy Kerr1-0/+1
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 <vince_chang@aspeedtech.com> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20251125-dev-forward-v1-1-54ecffcd0616@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-02net: mctp: mctp_fraq_queue should take ownership of passed skbJeremy Kerr1-16/+19
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 <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250829-mctp-skb-unshare-v1-1-1c28fe10235a@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-15net: mctp: Allow limiting binds to a peer addressMatt Johnston1-1/+5
Prior to calling bind() a program may call connect() on a socket to restrict to a remote peer address. Using connect() is the normal mechanism to specify a remote network peer, so we use that here. In MCTP connect() is only used for bound sockets - send() is not available for MCTP since a tag must be provided for each message. The smctp_type must match between connect() and bind() calls. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Link: https://patch.msgid.link/20250710-mctp-bind-v4-6-8ec2f6460c56@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-15net: mctp: Use hashtable for bindsMatt Johnston1-14/+61
Ensure that a specific EID (remote or local) bind will match in preference to a MCTP_ADDR_ANY bind. This adds infrastructure for binding a socket to receive messages from a specific remote peer address, a future commit will expose an API for this. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Link: https://patch.msgid.link/20250710-mctp-bind-v4-5-8ec2f6460c56@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: add gateway routing supportJeremy Kerr1-55/+151
This change allows for gateway routing, where a route table entry may reference a routable endpoint (by network and EID), instead of routing directly to a netdevice. We add support for a RTM_GATEWAY attribute for netlink route updates, with an attribute format of: struct mctp_fq_addr { unsigned int net; mctp_eid_t eid; } - we need the net here to uniquely identify the target EID, as we no longer have the device reference directly (which would provide the net id in the case of direct routes). This makes route lookups recursive, as a route lookup that returns a gateway route must be resolved into a direct route (ie, to a device) eventually. We provide a limit to the route lookups, to prevent infinite loop routing. The route lookup populates a new 'nexthop' field in the dst structure, which now specifies the key for the neighbour table lookup on device output, rather than using the packet destination address directly. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-13-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: allow NL parsing directly into a struct mctp_routeJeremy Kerr1-62/+140
The netlink route parsing functions end up setting a bunch of output variables from the rt attributes. This will get messy when the routes become more complex. So, split the rt parsing into two types: a lookup (returning route target data suitable for a route lookup, like when deleting a route) and a populate (setting fields of a struct mctp_route). In doing this, we need to separate the route allocation from mctp_route_add, so add some comments on the lifetime semantics for the latter. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-12-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: remove routes by netid, not by deviceJeremy Kerr1-4/+10
In upcoming changes, a route may not have a device associated. Since the route is matched on the (network, eid) tuple, pass the netid itself into mctp_route_remove. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-11-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: pass net into route creationJeremy Kerr1-15/+16
We may not have a mdev pointer, from which we currently extract the net. Instead, pass the net directly. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-10-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: test: Add initial socket testsJeremy Kerr1-0/+5
Recent changes have modified the extaddr path a little, so add a couple of kunit tests to af-mctp.c. These check that we're correctly passing lladdr data between sendmsg/recvmsg and the routing layer. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-9-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: separate cb from direct-addressing routingJeremy Kerr1-16/+5
Now that we have the dst->haddr populated by sendmsg (when extended addressing is in use), we no longer need to stash the link-layer address in the skb->cb. Instead, only use skb->cb for incoming lladdr data. While we're at it: remove cb->src, as was never used. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-4-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: separate routing database from routing operationsJeremy Kerr1-100/+110
This change adds a struct mctp_dst, representing the result of a routing lookup. This decouples the struct mctp_route from the actual implementation of a routing operation. This will allow for future routing changes which may require more involved lookup logic, such as gateway routing - which may require multiple traversals of the routing table. Since we only use the struct mctp_route at lookup time, we no longer hold routes over a routing operation, as we only need it to populate the dst. However, we do hold the dev while the dst is active. This requires some changes to the route test infrastructure, as we no longer have a mock route to handle the route output operation, and transient dsts are created by the routing code, so we can't override them as easily. Instead, we use kunit->priv to stash a packet queue, and a custom dst_output function queues into that packet queue, which we can use for later expectations. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-3-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-08net: mctp: don't use source cb data when forwarding, ensure pkt_type is setJeremy Kerr1-1/+12
In the output path, only check the skb->cb data when we know it's from a local socket; input packets will have source address information there instead. In order to detect when we're forwarding, set skb->pkt_type on input/output. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20250702-dev-forwarding-v5-1-1468191da8a4@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-09net: mctp: Ensure keys maintain only one ref to corresponding devAndrew Jeffery1-1/+3
mctp_flow_prepare_output() is called in mctp_route_output(), which places outbound packets onto a given interface. The packet may represent a message fragment, in which case we provoke an unbalanced reference count to the underlying device. This causes trouble if we ever attempt to remove the interface: [ 48.702195] usb 1-1: USB disconnect, device number 2 [ 58.883056] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2 [ 69.022548] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2 [ 79.172568] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2 ... Predicate the invocation of mctp_dev_set_key() in mctp_flow_prepare_output() on not already having associated the device with the key. It's not yet realistic to uphold the property that the key maintains only one device reference earlier in the transmission sequence as the route (and therefore the device) may not be known at the time the key is associated with the socket. Fixes: 67737c457281 ("mctp: Pass flow data & flow release events to drivers") Acked-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au> Link: https://patch.msgid.link/20250508-mctp-dev-refcount-v1-1-d4f965c67bb5@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-11net: mctp: unshare packets when reassemblingMatt Johnston1-2/+8
Ensure that the frag_list used for reassembly isn't shared with other packets. This avoids incorrect reassembly when packets are cloned, and prevents a memory leak due to circular references between fragments and their skb_shared_info. The upcoming MCTP-over-USB driver uses skb_clone which can trigger the problem - other MCTP drivers don't share SKBs. A kunit test is added to reproduce the issue. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Fixes: 4a992bbd3650 ("mctp: Implement message fragmentation & reassembly") Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250306-matt-mctp-usb-v1-1-085502b3dd28@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-12-19net: mctp: handle skb cleanup on sock_queue failuresJeremy Kerr1-10/+26
Currently, we don't use the return value from sock_queue_rcv_skb, which means we may leak skbs if a message is not successfully queued to a socket. Instead, ensure that we're freeing the skb where the sock hasn't otherwise taken ownership of the skb by adding checks on the sock_queue_rcv_skb() to invoke a kfree on failure. In doing so, rather than using the 'rc' value to trigger the kfree_skb(), use the skb pointer itself, which is more explicit. Also, add a kunit test for the sock delivery failure cases. Fixes: 4a992bbd3650 ("mctp: Implement message fragmentation & reassembly") Cc: stable@vger.kernel.org Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20241218-mctp-next-v2-1-1c1729645eaa@codeconstruct.com.au Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-10mctp: Handle error of rtnl_register_module().Kuniyuki Iwashima1-10/+23
Since introduced, mctp has been ignoring the returned value of rtnl_register_module(), which could fail silently. Handling the error allows users to view a module as an all-or-nothing thing in terms of the rtnetlink functionality. This prevents syzkaller from reporting spurious errors from its tests, where OOM often occurs and module is automatically loaded. Let's handle the errors by rtnl_register_many(). Fixes: 583be982d934 ("mctp: Add device handling and netlink interface") Fixes: 831119f88781 ("mctp: Add neighbour netlink interface") Fixes: 06d2f4c583a7 ("mctp: Add netlink route management") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-2/+8
Cross-merge networking fixes after downstream PR. Conflicts: net/mptcp/protocol.c adf1bb78dab5 ("mptcp: fix snd_wnd initialization for passive socket") 9426ce476a70 ("mptcp: annotate lockless access for RX path fields") https://lore.kernel.org/all/20240228103048.19255709@canb.auug.org.au/ Adjacent changes: drivers/dpll/dpll_core.c 0d60d8df6f49 ("dpll: rely on rcu for netdev_dpll_pin()") e7f8df0e81bf ("dpll: move xa_erase() call in to match dpll_pin_alloc() error path order") drivers/net/veth.c 1ce7d306ea63 ("veth: try harder when allocating queue memory") 0bef512012b1 ("net: add netdev_lockdep_set_classes() to virtual drivers") drivers/net/wireless/intel/iwlwifi/mvm/d3.c 8c9bef26e98b ("wifi: iwlwifi: mvm: d3: implement suspend with MLO") 78f65fbf421a ("wifi: iwlwifi: mvm: ensure offloading TID queue exists") net/wireless/nl80211.c f78c1375339a ("wifi: nl80211: reject iftype change with mesh ID change") 414532d8aa89 ("wifi: cfg80211: use IEEE80211_MAX_MESH_ID_LEN appropriately") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22net: mctp: take ownership of skb in mctp_local_outputJeremy Kerr1-2/+8
Currently, mctp_local_output only takes ownership of skb on success, and we may leak an skb if mctp_local_output fails in specific states; the skb ownership isn't transferred until the actual output routing occurs. Instead, make mctp_local_output free the skb on all error paths up to the route action, so it always consumes the passed skb. Fixes: 833ef3b91de6 ("mctp: Populate socket implementation") Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240220081053.1439104-1-jk@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+1
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/udp.c f796feabb9f5 ("udp: add local "peek offset enabled" flag") 56667da7399e ("net: implement lockless setsockopt(SO_PEEK_OFF)") Adjacent changes: net/unix/garbage.c aa82ac51d633 ("af_unix: Drop oob_skb ref before purging queue in GC.") 11498715f266 ("af_unix: Remove io_uring code for GC.") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22net: mctp: copy skb ext data when fragmentingJeremy Kerr1-0/+3
If we're fragmenting on local output, the original packet may contain ext data for the MCTP flows. We'll want this in the resulting fragment skbs too. So, do a skb_ext_copy() in the fragmentation path, and implement the MCTP-specific parts of an ext copy operation. Fixes: 67737c457281 ("mctp: Pass flow data & flow release events to drivers") Reported-by: Jian Zhang <zhangjian.3032@bytedance.com> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-22net: mctp: separate key correlation across netsJeremy Kerr1-12/+31
Currently, we lookup sk_keys from the entire struct net_namespace, which may contain multiple MCTP net IDs. In those cases we want to distinguish between endpoints with the same EID but different net ID. Add the net ID data to the struct mctp_sk_key, populate on add and filter on this during route lookup. For the ioctl interface, we use a default net of MCTP_INITIAL_DEFAULT_NET (ie., what will be in use for single-net configurations), but we'll extend the ioctl interface to provide net-specific tag allocation in an upcoming change. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-22net: mctp: make key lookups match the ANY address on either local or peerJeremy Kerr1-3/+11
We may have an ANY address in either the local or peer address of a sk_key, and may want to match on an incoming daddr or saddr being ANY. Do this by altering the conflicting-tag lookup to also accept ANY as the local/peer address. We don't want mctp_address_matches to match on the requested EID being ANY, as that is a specific lookup case on packet input. Reported-by: Eric Chuang <echuang@google.com> Reported-by: Anthony <anthonyhkf@google.com> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-22net: mctp: Add some detail on the key allocation implementationJeremy Kerr1-0/+37
We could do with a little more comment on where MCTP_ADDR_ANY will match in the key allocations. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-22net: mctp: avoid confusion over local/peer dest/source addressesJeremy Kerr1-8/+8
We have a double-swap of local and peer addresses in mctp_alloc_local_tag; the arguments in both call sites are swapped, but there is also a swap in the implementation of alloc_local_tag. This is opaque because we're using source/dest address references, which don't match the local/peer semantics. Avoid this confusion by naming the arguments as 'local' and 'peer', and remove the double swap. The calling order now matches mctp_key_alloc. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-21net: mctp: put sock on tag allocation failureJeremy Kerr1-1/+1
We may hold an extra reference on a socket if a tag allocation fails: we optimistically allocate the sk_key, and take a ref there, but do not drop if we end up not using the allocated key. Ensure we're dropping the sock on this failure by doing a proper unref rather than directly kfree()ing. Fixes: de8a6b15d965 ("net: mctp: add an explicit reference from a mctp_sk_key to sock") Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/ce9b61e44d1cdae7797be0c5e3141baf582d23a0.1707983487.git.jk@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-10mctp: perform route lookups under a RCU read-side lockJeremy Kerr1-6/+16
Our current route lookups (mctp_route_lookup and mctp_route_lookup_null) traverse the net's route list without the RCU read lock held. This means the route lookup is subject to preemption, resulting in an potential grace period expiry, and so an eventual kfree() while we still have the route pointer. Add the proper read-side critical section locks around the route lookups, preventing premption and a possible parallel kfree. The remaining net->mctp.routes accesses are already under a rcu_read_lock, or protected by the RTNL for updates. Based on an analysis from Sili Luo <rootlab@huawei.com>, where introducing a delay in the route lookup could cause a UAF on simultaneous sendmsg() and route deletion. Reported-by: Sili Luo <rootlab@huawei.com> Fixes: 889b7da23abf ("mctp: Add initial routing framework") Cc: stable@vger.kernel.org Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/29c4b0e67dc1bf3571df3982de87df90cae9b631.1696837310.git.jk@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-17net: mctp: remove redundant RTN_UNICAST checkLin Ma1-3/+0
Current mctp_newroute() contains two exactly same check against rtm->rtm_type static int mctp_newroute(...) { ... if (rtm->rtm_type != RTN_UNICAST) { // (1) NL_SET_ERR_MSG(extack, "rtm_type must be RTN_UNICAST"); return -EINVAL; } ... if (rtm->rtm_type != RTN_UNICAST) // (2) return -EINVAL; ... } This commits removes the (2) check as it is redundant. Signed-off-by: Lin Ma <linma@zju.edu.cn> Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Acked-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://lore.kernel.org/r/20230615152240.1749428-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-25net: mctp: mark socks as dead on unhash, prevent re-addJeremy Kerr1-0/+6
Once a socket has been unhashed, we want to prevent it from being re-used in a sk_key entry as part of a routing operation. This change marks the sk as SOCK_DEAD on unhash, which prevents addition into the net's key list. We need to do this during the key add path, rather than key lookup, as we release the net keys_lock between those operations. Fixes: 4a992bbd3650 ("mctp: Implement message fragmentation & reassembly") Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-25net: mctp: hold key reference when looking up a general keyPaolo Abeni1-7/+7
Currently, we have a race where we look up a sock through a "general" (ie, not directly associated with the (src,dest,tag) tuple) key, then drop the key reference while still holding the key's sock. This change expands the key reference until we've finished using the sock, and hence the sock reference too. Commit message changes from Jeremy Kerr <jk@codeconstruct.com.au>. Reported-by: Noam Rathaus <noamr@ssd-disclosure.com> Fixes: 73c618456dc5 ("mctp: locking, lifetime and validity changes for sk_keys") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-25net: mctp: add an explicit reference from a mctp_sk_key to sockJeremy Kerr1-6/+8
Currently, we correlate the mctp_sk_key lifetime to the sock lifetime through the sock hash/unhash operations, but this is pretty tenuous, and there are cases where we may have a temporary reference to an unhashed sk. This change makes the reference more explicit, by adding a hold on the sock when it's associated with a mctp_sk_key, released on final key unref. Fixes: 73c618456dc5 ("mctp: locking, lifetime and validity changes for sk_keys") Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-09mctp: Fix an error handling path in mctp_init()Wei Yongjun1-1/+1
If mctp_neigh_init() return error, the routes resources should be released in the error handling path. Otherwise some resources leak. Fixes: 4d8b9319282a ("mctp: Add neighbour implementation") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Matt Johnston <matt@codeconstruct.com.au> Link: https://lore.kernel.org/r/20221108095517.620115-1-weiyongjun@huaweicloud.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-12mctp: prevent double key removal and unrefJeremy Kerr1-5/+5
Currently, we have a bug where a simultaneous DROPTAG ioctl and socket close may race, as we attempt to remove a key from lists twice, and perform an unref for each removal operation. This may result in a uaf when we attempt the second unref. This change fixes the race by making __mctp_key_remove tolerant to being called on a key that has already been removed from the socket/net lists, and only performs the unref when we do the actual remove. We also need to hold the list lock on the ioctl cleanup path. This fix is based on a bug report and comprehensive analysis from butt3rflyh4ck <butterflyhuangxx@gmail.com>, found via syzkaller. Cc: stable@vger.kernel.org Fixes: 63ed1aab3d40 ("mctp: Add SIOCMCTP{ALLOC,DROP}TAG ioctls for tag control") Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-01mctp: Use output netdev to allocate skb headroomMatt Johnston1-3/+11
Previously the skb was allocated with headroom MCTP_HEADER_MAXLEN, but that isn't sufficient if we are using devs that are not MCTP specific. This also adds a check that the smctp_halen provided to sendmsg for extended addressing is the correct size for the netdev. Fixes: 833ef3b91de6 ("mctp: Populate socket implementation") Reported-by: Matthew Rinaldi <mjrinal@g.clemson.edu> Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-01mctp: Fix check for dev_hard_header() resultMatt Johnston1-1/+1
dev_hard_header() returns the length of the header, so we need to test for negative errors rather than non-zero. Fixes: 889b7da23abf ("mctp: Add initial routing framework") Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23mctp: Fix warnings reported by clang-analyzerMatt Johnston1-1/+0
net/mctp/device.c:140:11: warning: Assigned value is garbage or undefined [clang-analyzer-core.uninitialized.Assign] mcb->idx = idx; - Not a real problem due to how the callback runs, fix the warning. net/mctp/route.c:458:4: warning: Value stored to 'msk' is never read [clang-analyzer-deadcode.DeadStores] msk = container_of(key->sk, struct mctp_sock, sk); - 'msk' dead assignment can be removed here. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23mctp: Fix incorrect netdev unref for extended addrMatt Johnston1-6/+2
In the extended addressing local route output codepath dev_get_by_index_rcu() doesn't take a dev_hold() so we shouldn't dev_put(). Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-23mctp: make __mctp_dev_get() take a refcount holdMatt Johnston1-1/+4
Previously there was a race that could allow the mctp_dev refcount to hit zero: rcu_read_lock(); mdev = __mctp_dev_get(dev); // mctp_unregister() happens here, mdev->refs hits zero mctp_dev_hold(dev); rcu_read_unlock(); Now we make __mctp_dev_get() take the hold itself. It is safe to test against the zero refcount because __mctp_dev_get() is called holding rcu_read_lock and mctp_dev uses kfree_rcu(). Reported-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-18mctp: add address validity checking for packet receiveJeremy Kerr1-0/+11
This change adds some basic sanity checks for the source and dest headers of packets on initial receive. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-18mctp: replace mctp_address_ok with more fine-grained helpersJeremy Kerr1-1/+1
Currently, we have mctp_address_ok(), which checks if an EID is in the "valid" range of 8-254 inclusive. However, 0 and 255 may also be valid addresses, depending on context. 0 is the NULL EID, which may be set when physical addressing is used. 255 is valid as a destination address for broadcasts. This change renames mctp_address_ok to mctp_address_unicast, and adds similar helpers for broadcast and null EIDs, which will be used in an upcoming commit. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-5/+6
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>