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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /net/llc/llc_input.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'net/llc/llc_input.c')
-rw-r--r--net/llc/llc_input.c224
1 files changed, 224 insertions, 0 deletions
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 <acme@conectiva.com.br>
+ */
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <net/net_namespace.h>
+#include <net/llc.h>
+#include <net/llc_pdu.h>
+#include <net/llc_sap.h>
+
+#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);