From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- net/llc/llc_input.c | 224 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 224 insertions(+) create mode 100644 net/llc/llc_input.c (limited to 'net/llc/llc_input.c') diff --git a/net/llc/llc_input.c b/net/llc/llc_input.c new file mode 100644 index 000000000..8eb3d73c3 --- /dev/null +++ b/net/llc/llc_input.c @@ -0,0 +1,224 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * llc_input.c - Minimal input path for LLC + * + * Copyright (c) 1997 by Procom Technology, Inc. + * 2001-2003 by Arnaldo Carvalho de Melo + */ +#include +#include +#include +#include +#include +#include +#include + +#if 0 +#define dprintk(args...) printk(KERN_DEBUG args) +#else +#define dprintk(args...) +#endif + +/* + * Packet handler for the station, registerable because in the minimal + * LLC core that is taking shape only the very minimal subset of LLC that + * is needed for things like IPX, Appletalk, etc will stay, with all the + * rest in the llc1 and llc2 modules. + */ +static void (*llc_station_handler)(struct sk_buff *skb); + +/* + * Packet handlers for LLC_DEST_SAP and LLC_DEST_CONN. + */ +static void (*llc_type_handlers[2])(struct llc_sap *sap, + struct sk_buff *skb); + +void llc_add_pack(int type, void (*handler)(struct llc_sap *sap, + struct sk_buff *skb)) +{ + smp_wmb(); /* ensure initialisation is complete before it's called */ + if (type == LLC_DEST_SAP || type == LLC_DEST_CONN) + llc_type_handlers[type - 1] = handler; +} + +void llc_remove_pack(int type) +{ + if (type == LLC_DEST_SAP || type == LLC_DEST_CONN) + llc_type_handlers[type - 1] = NULL; + synchronize_net(); +} + +void llc_set_station_handler(void (*handler)(struct sk_buff *skb)) +{ + /* Ensure initialisation is complete before it's called */ + if (handler) + smp_wmb(); + + llc_station_handler = handler; + + if (!handler) + synchronize_net(); +} + +/** + * llc_pdu_type - returns which LLC component must handle for PDU + * @skb: input skb + * + * This function returns which LLC component must handle this PDU. + */ +static __inline__ int llc_pdu_type(struct sk_buff *skb) +{ + int type = LLC_DEST_CONN; /* I-PDU or S-PDU type */ + struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb); + + if ((pdu->ctrl_1 & LLC_PDU_TYPE_MASK) != LLC_PDU_TYPE_U) + goto out; + switch (LLC_U_PDU_CMD(pdu)) { + case LLC_1_PDU_CMD_XID: + case LLC_1_PDU_CMD_UI: + case LLC_1_PDU_CMD_TEST: + type = LLC_DEST_SAP; + break; + case LLC_2_PDU_CMD_SABME: + case LLC_2_PDU_CMD_DISC: + case LLC_2_PDU_RSP_UA: + case LLC_2_PDU_RSP_DM: + case LLC_2_PDU_RSP_FRMR: + break; + default: + type = LLC_DEST_INVALID; + break; + } +out: + return type; +} + +/** + * llc_fixup_skb - initializes skb pointers + * @skb: This argument points to incoming skb + * + * Initializes internal skb pointer to start of network layer by deriving + * length of LLC header; finds length of LLC control field in LLC header + * by looking at the two lowest-order bits of the first control field + * byte; field is either 3 or 4 bytes long. + */ +static inline int llc_fixup_skb(struct sk_buff *skb) +{ + u8 llc_len = 2; + struct llc_pdu_un *pdu; + + if (unlikely(!pskb_may_pull(skb, sizeof(*pdu)))) + return 0; + + pdu = (struct llc_pdu_un *)skb->data; + if ((pdu->ctrl_1 & LLC_PDU_TYPE_MASK) == LLC_PDU_TYPE_U) + llc_len = 1; + llc_len += 2; + + if (unlikely(!pskb_may_pull(skb, llc_len))) + return 0; + + skb_pull(skb, llc_len); + skb_reset_transport_header(skb); + if (skb->protocol == htons(ETH_P_802_2)) { + __be16 pdulen; + s32 data_size; + + if (skb->mac_len < ETH_HLEN) + return 0; + + pdulen = eth_hdr(skb)->h_proto; + data_size = ntohs(pdulen) - llc_len; + + if (data_size < 0 || + !pskb_may_pull(skb, data_size)) + return 0; + if (unlikely(pskb_trim_rcsum(skb, data_size))) + return 0; + } + return 1; +} + +/** + * llc_rcv - 802.2 entry point from net lower layers + * @skb: received pdu + * @dev: device that receive pdu + * @pt: packet type + * @orig_dev: the original receive net device + * + * When the system receives a 802.2 frame this function is called. It + * checks SAP and connection of received pdu and passes frame to + * llc_{station,sap,conn}_rcv for sending to proper state machine. If + * the frame is related to a busy connection (a connection is sending + * data now), it queues this frame in the connection's backlog. + */ +int llc_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + struct llc_sap *sap; + struct llc_pdu_sn *pdu; + int dest; + int (*rcv)(struct sk_buff *, struct net_device *, + struct packet_type *, struct net_device *); + void (*sta_handler)(struct sk_buff *skb); + void (*sap_handler)(struct llc_sap *sap, struct sk_buff *skb); + + /* + * When the interface is in promisc. mode, drop all the crap that it + * receives, do not try to analyse it. + */ + if (unlikely(skb->pkt_type == PACKET_OTHERHOST)) { + dprintk("%s: PACKET_OTHERHOST\n", __func__); + goto drop; + } + skb = skb_share_check(skb, GFP_ATOMIC); + if (unlikely(!skb)) + goto out; + if (unlikely(!llc_fixup_skb(skb))) + goto drop; + pdu = llc_pdu_sn_hdr(skb); + if (unlikely(!pdu->dsap)) /* NULL DSAP, refer to station */ + goto handle_station; + sap = llc_sap_find(pdu->dsap); + if (unlikely(!sap)) {/* unknown SAP */ + dprintk("%s: llc_sap_find(%02X) failed!\n", __func__, + pdu->dsap); + goto drop; + } + /* + * First the upper layer protocols that don't need the full + * LLC functionality + */ + rcv = rcu_dereference(sap->rcv_func); + dest = llc_pdu_type(skb); + sap_handler = dest ? READ_ONCE(llc_type_handlers[dest - 1]) : NULL; + if (unlikely(!sap_handler)) { + if (rcv) + rcv(skb, dev, pt, orig_dev); + else + kfree_skb(skb); + } else { + if (rcv) { + struct sk_buff *cskb = skb_clone(skb, GFP_ATOMIC); + if (cskb) + rcv(cskb, dev, pt, orig_dev); + } + sap_handler(sap, skb); + } + llc_sap_put(sap); +out: + return 0; +drop: + kfree_skb(skb); + goto out; +handle_station: + sta_handler = READ_ONCE(llc_station_handler); + if (!sta_handler) + goto drop; + sta_handler(skb); + goto out; +} + +EXPORT_SYMBOL(llc_add_pack); +EXPORT_SYMBOL(llc_remove_pack); +EXPORT_SYMBOL(llc_set_station_handler); -- cgit v1.3.1