kernel/linux.git/net/can/raw.c, branch v7.1.6

can: raw: add locking for raw flags bitfield

2026-08-03T09:25:22+00:00

[ Upstream commit 1e5185c090589f4146d728ab36417d8a5419f127 ] With commit 890e5198a6e5 ("can: raw: use bitfields to store flags in struct raw_sock") the formerly separate integer values have been integrated into a single bitfield. This led to a read-modify-write operation when changing a flag in raw_setsockopt() which now needs a locking to prevent concurrent access. Instead of adding a lock/unlock hell in each of the flag manipulations this patch introduces a wrapper for a new raw_setsockopt_locked() function analogue to the isotp_setsockopt[_locked]() approach in net/can/isotp.c Fixes: 890e5198a6e5 ("can: raw: use bitfields to store flags in struct raw_sock") Reported-by: Eulgyu Kim Closes: https://lore.kernel.org/linux-can/20260503112200.22727-1-eulgyukim@snu.ac.kr/ Tested-by: Eulgyu Kim Signed-off-by: Oliver Hartkopp Reviewed-by: Vincent Mailhol Tested-by: Vincent Mailhol Link: https://patch.msgid.link/20260504111928.41856-1-socketcan@hartkopp.net [mkl: use Closes tag instead of Link] Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

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

2026-04-14T19:04:00+00:00

Merge in late fixes in preparation for the net-next PR. Conflicts: include/net/sch_generic.h a6bd339dbb351 ("net_sched: fix skb memory leak in deferred qdisc drops") ff2998f29f390 ("net: sched: introduce qdisc-specific drop reason tracing") https://lore.kernel.org/adz0iX85FHMz0HdO@sirena.org.uk drivers/net/ethernet/airoha/airoha_eth.c 1acdfbdb516b ("net: airoha: Fix VIP configuration for AN7583 SoC") bf3471e6e6c0 ("net: airoha: Make flow control source port mapping dependent on nbq parameter") Adjacent changes: drivers/net/ethernet/airoha/airoha_ppe.c f44218cd5e6a ("net: airoha: Reset PPE cpu port configuration in airoha_ppe_hw_init()") 7da62262ec96 ("inet: add ip_local_port_step_width sysctl to improve port usage distribution") Signed-off-by: Jakub Kicinski

can: raw: convert to getsockopt_iter

2026-04-13T21:56:29+00:00

Convert CAN raw socket's getsockopt implementation to use the new getsockopt_iter callback with sockopt_t. Key changes: - Replace (char __user *optval, int __user *optlen) with sockopt_t *opt - Use opt->optlen for buffer length (input) and returned size (output) - Use copy_to_iter() instead of copy_to_user() - For CAN_RAW_FILTER and CAN_RAW_XL_VCID_OPTS: on -ERANGE, set opt->optlen to the required buffer size. The wrapper writes this back to userspace even on error, preserving the existing API that lets userspace discover the needed allocation size. Signed-off-by: Breno Leitao Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20260408-getsockopt-v3-4-061bb9cb355d@debian.org Signed-off-by: Jakub Kicinski

net: change sock_queue_rcv_skb_reason() to return a drop_reason

2026-04-12T21:30:25+00:00

Change sock_queue_rcv_skb_reason() to return the drop_reason directly instead of using a reference. This is part of an effort to remove stack canaries and reduce bloat. $ scripts/bloat-o-meter -t vmlinux.old vmlinux.new add/remove: 0/0 grow/shrink: 3/7 up/down: 79/-301 (-222) Function old new delta vsock_queue_rcv_skb 50 79 +29 ipmr_cache_report 1290 1315 +25 ip6mr_cache_report 1322 1347 +25 packet_rcv_spkt 329 327 -2 sock_queue_rcv_skb_reason 166 128 -38 raw_rcv_skb 122 80 -42 ping_queue_rcv_skb 109 61 -48 ping_rcv 215 162 -53 rawv6_rcv_skb 278 224 -54 raw_rcv 591 527 -64 Total: Before=29722890, After=29722668, chg -0.00% Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260409145625.2306224-2-edumazet@google.com Signed-off-by: Jakub Kicinski

can: raw: fix ro->uniq use-after-free in raw_rcv()

2026-04-09T16:51:42+00:00

raw_release() unregisters raw CAN receive filters via can_rx_unregister(), but receiver deletion is deferred with call_rcu(). This leaves a window where raw_rcv() may still be running in an RCU read-side critical section after raw_release() frees ro->uniq, leading to a use-after-free of the percpu uniq storage. Move free_percpu(ro->uniq) out of raw_release() and into a raw-specific socket destructor. can_rx_unregister() takes an extra reference to the socket and only drops it from the RCU callback, so freeing uniq from sk_destruct ensures the percpu area is not released until the relevant callbacks have drained. Fixes: 514ac99c64b2 ("can: fix multiple delivery of a single CAN frame for overlapping CAN filters") Cc: stable@vger.kernel.org # v4.1+ Assisted-by: Bynario AI Signed-off-by: Samuel Page Link: https://patch.msgid.link/26ec626d-cae7-4418-9782-7198864d070c@bynar.io Acked-by: Oliver Hartkopp [mkl: applied manually] Signed-off-by: Marc Kleine-Budde

can: remove private CAN skb headroom infrastructure

2026-02-05T10:58:40+00:00

This patch removes struct can_skb_priv which was stored at skb->head and the can_skb_reserve() helper which was used to shift skb->head. Signed-off-by: Marc Kleine-Budde Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260201-can_skb_ext-v8-5-3635d790fe8b@hartkopp.net Signed-off-by: Paolo Abeni

can: move ifindex to CAN skb extensions

2026-02-05T10:58:40+00:00

When routing CAN frames over different CAN interfaces the interface index skb->iif is overwritten with every single hop. To prevent sending a CAN frame back to its originating (first) incoming CAN interface another ifindex variable is needed, which was stored in can_skb_priv::ifindex. Move the can_skb_priv::ifindex content to can_skb_ext::can_iif. Signed-off-by: Marc Kleine-Budde Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260201-can_skb_ext-v8-3-3635d790fe8b@hartkopp.net Signed-off-by: Paolo Abeni

can: add CAN skb extension infrastructure

2026-02-05T10:58:39+00:00

To remove the private CAN bus skb headroom infrastructure 8 bytes need to be stored in the skb. The skb extensions are a common pattern and an easy and efficient way to hold private data travelling along with the skb. We only need the skb_ext_add() and skb_ext_find() functions to allocate and access CAN specific content as the skb helpers to copy/clone/free skbs automatically take care of skb extensions and their final removal. This patch introduces the complete CAN skb extensions infrastructure: - add struct can_skb_ext in new file include/net/can.h - add include/net/can.h in MAINTAINERS - add SKB_EXT_CAN to skbuff.c and skbuff.h - select SKB_EXTENSIONS in Kconfig when CONFIG_CAN is enabled - check for existing CAN skb extensions in can_rcv() in af_can.c - add CAN skb extensions allocation at every skb_alloc() location - duplicate the skb extensions if cloning outgoing skbs (framelen/gw_hops) - introduce can_skb_ext_add() and can_skb_ext_find() helpers The patch also corrects an indention issue in the original code from 2018: Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202602010426.PnGrYAk3-lkp@intel.com/ Signed-off-by: Marc Kleine-Budde Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260201-can_skb_ext-v8-2-3635d790fe8b@hartkopp.net Signed-off-by: Paolo Abeni

can: use skb hash instead of private variable in headroom

2026-02-05T10:58:39+00:00

The can_skb_priv::skbcnt variable is used to identify CAN skbs in the RX path analogue to the skb->hash. As the skb hash is not filled in CAN skbs move the private skbcnt value to skb->hash and set skb->sw_hash accordingly. The skb->hash is a value used for RPS to identify skbs. Use it as intended. Signed-off-by: Marc Kleine-Budde Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260201-can_skb_ext-v8-1-3635d790fe8b@hartkopp.net Signed-off-by: Paolo Abeni

can: raw: instantly reject disabled CAN frames

2026-01-15T08:52:04+00:00

For real CAN interfaces the CAN_CTRLMODE_FD and CAN_CTRLMODE_XL control modes indicate whether an interface can handle those CAN FD/XL frames. In the case a CAN XL interface is configured in CANXL-only mode with disabled error-signalling neither CAN CC nor CAN FD frames can be sent. The checks are now performed on CAN_RAW sockets to give an instant feedback to the user when writing unsupported CAN frames to the interface or when the CAN interface is in read-only mode. Fixes: 1a620a723853 ("can: raw: instantly reject unsupported CAN frames") Cc: Marc Kleine-Budde Cc: Arnd Bergmann Cc: Vincent Mailhol Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260109144135.8495-4-socketcan@hartkopp.net [mkl: fix dev reference leak] Link: https://lore.kernel.org/all/0636c732-2e71-4633-8005-dfa85e1da445@hartkopp.net Signed-off-by: Marc Kleine-Budde