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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /net/sctp/chunk.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
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 ...
Diffstat (limited to 'net/sctp/chunk.c')
-rw-r--r--net/sctp/chunk.c354
1 files changed, 354 insertions, 0 deletions
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
new file mode 100644
index 000000000..5b889e89e
--- /dev/null
+++ b/net/sctp/chunk.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2003, 2004
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * This file contains the code relating the chunk abstraction.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ * lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ * Jon Grimm <jgrimm@us.ibm.com>
+ * Sridhar Samudrala <sri@us.ibm.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/inet.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <net/sock.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+/* This file is mostly in anticipation of future work, but initially
+ * populate with fragment tracking for an outbound message.
+ */
+
+/* Initialize datamsg from memory. */
+static void sctp_datamsg_init(struct sctp_datamsg *msg)
+{
+ refcount_set(&msg->refcnt, 1);
+ msg->send_failed = 0;
+ msg->send_error = 0;
+ msg->can_delay = 1;
+ msg->abandoned = 0;
+ msg->expires_at = 0;
+ INIT_LIST_HEAD(&msg->chunks);
+}
+
+/* Allocate and initialize datamsg. */
+static struct sctp_datamsg *sctp_datamsg_new(gfp_t gfp)
+{
+ struct sctp_datamsg *msg;
+ msg = kmalloc_obj(struct sctp_datamsg, gfp);
+ if (msg) {
+ sctp_datamsg_init(msg);
+ SCTP_DBG_OBJCNT_INC(datamsg);
+ }
+ return msg;
+}
+
+void sctp_datamsg_free(struct sctp_datamsg *msg)
+{
+ struct sctp_chunk *chunk;
+
+ /* This doesn't have to be a _safe vairant because
+ * sctp_chunk_free() only drops the refs.
+ */
+ list_for_each_entry(chunk, &msg->chunks, frag_list)
+ sctp_chunk_free(chunk);
+
+ sctp_datamsg_put(msg);
+}
+
+/* Final destructruction of datamsg memory. */
+static void sctp_datamsg_destroy(struct sctp_datamsg *msg)
+{
+ struct sctp_association *asoc = NULL;
+ struct list_head *pos, *temp;
+ struct sctp_chunk *chunk;
+ struct sctp_ulpevent *ev;
+ int error, sent;
+
+ /* Release all references. */
+ list_for_each_safe(pos, temp, &msg->chunks) {
+ list_del_init(pos);
+ chunk = list_entry(pos, struct sctp_chunk, frag_list);
+
+ if (!msg->send_failed) {
+ sctp_chunk_put(chunk);
+ continue;
+ }
+
+ asoc = chunk->asoc;
+ error = msg->send_error ?: asoc->outqueue.error;
+ sent = chunk->has_tsn ? SCTP_DATA_SENT : SCTP_DATA_UNSENT;
+
+ if (sctp_ulpevent_type_enabled(asoc->subscribe,
+ SCTP_SEND_FAILED)) {
+ ev = sctp_ulpevent_make_send_failed(asoc, chunk, sent,
+ error, GFP_ATOMIC);
+ if (ev)
+ asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+ }
+
+ if (sctp_ulpevent_type_enabled(asoc->subscribe,
+ SCTP_SEND_FAILED_EVENT)) {
+ ev = sctp_ulpevent_make_send_failed_event(asoc, chunk,
+ sent, error,
+ GFP_ATOMIC);
+ if (ev)
+ asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+ }
+
+ sctp_chunk_put(chunk);
+ }
+
+ SCTP_DBG_OBJCNT_DEC(datamsg);
+ kfree(msg);
+}
+
+/* Hold a reference. */
+static void sctp_datamsg_hold(struct sctp_datamsg *msg)
+{
+ refcount_inc(&msg->refcnt);
+}
+
+/* Release a reference. */
+void sctp_datamsg_put(struct sctp_datamsg *msg)
+{
+ if (refcount_dec_and_test(&msg->refcnt))
+ sctp_datamsg_destroy(msg);
+}
+
+/* Assign a chunk to this datamsg. */
+static void sctp_datamsg_assign(struct sctp_datamsg *msg, struct sctp_chunk *chunk)
+{
+ sctp_datamsg_hold(msg);
+ chunk->msg = msg;
+}
+
+
+/* A data chunk can have a maximum payload of (2^16 - 20). Break
+ * down any such message into smaller chunks. Opportunistically, fragment
+ * the chunks down to the current MTU constraints. We may get refragmented
+ * later if the PMTU changes, but it is _much better_ to fragment immediately
+ * with a reasonable guess than always doing our fragmentation on the
+ * soft-interrupt.
+ */
+struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
+ struct sctp_sndrcvinfo *sinfo,
+ struct iov_iter *from)
+{
+ size_t len, first_len, max_data, remaining;
+ size_t msg_len = iov_iter_count(from);
+ struct sctp_shared_key *shkey = NULL;
+ struct list_head *pos, *temp;
+ struct sctp_chunk *chunk;
+ struct sctp_datamsg *msg;
+ int err;
+
+ msg = sctp_datamsg_new(GFP_KERNEL);
+ if (!msg)
+ return ERR_PTR(-ENOMEM);
+
+ /* Note: Calculate this outside of the loop, so that all fragments
+ * have the same expiration.
+ */
+ if (asoc->peer.prsctp_capable && sinfo->sinfo_timetolive &&
+ (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags) ||
+ !SCTP_PR_POLICY(sinfo->sinfo_flags)))
+ msg->expires_at = jiffies +
+ msecs_to_jiffies(sinfo->sinfo_timetolive);
+
+ /* This is the biggest possible DATA chunk that can fit into
+ * the packet
+ */
+ max_data = asoc->frag_point;
+ if (unlikely(!max_data)) {
+ max_data = sctp_min_frag_point(sctp_sk(asoc->base.sk),
+ sctp_datachk_len(&asoc->stream));
+ pr_warn_ratelimited("%s: asoc:%p frag_point is zero, forcing max_data to default minimum (%zu)",
+ __func__, asoc, max_data);
+ }
+
+ /* If the peer requested that we authenticate DATA chunks
+ * we need to account for bundling of the AUTH chunks along with
+ * DATA.
+ */
+ if (sctp_auth_send_cid(SCTP_CID_DATA, asoc)) {
+ const struct sctp_hmac *hmac_desc =
+ sctp_auth_asoc_get_hmac(asoc);
+
+ if (hmac_desc)
+ max_data -= SCTP_PAD4(sizeof(struct sctp_auth_chunk) +
+ hmac_desc->hmac_len);
+
+ if (sinfo->sinfo_tsn &&
+ sinfo->sinfo_ssn != asoc->active_key_id) {
+ shkey = sctp_auth_get_shkey(asoc, sinfo->sinfo_ssn);
+ if (!shkey) {
+ err = -EINVAL;
+ goto errout;
+ }
+ } else {
+ shkey = asoc->shkey;
+ }
+ }
+
+ /* Set first_len and then account for possible bundles on first frag */
+ first_len = max_data;
+
+ /* Check to see if we have a pending SACK and try to let it be bundled
+ * with this message. Do this if we don't have any data queued already.
+ * To check that, look at out_qlen and retransmit list.
+ * NOTE: we will not reduce to account for SACK, if the message would
+ * not have been fragmented.
+ */
+ if (timer_pending(&asoc->timers[SCTP_EVENT_TIMEOUT_SACK]) &&
+ asoc->outqueue.out_qlen == 0 &&
+ list_empty(&asoc->outqueue.retransmit) &&
+ msg_len > max_data)
+ first_len -= SCTP_PAD4(sizeof(struct sctp_sack_chunk));
+
+ /* Encourage Cookie-ECHO bundling. */
+ if (asoc->state < SCTP_STATE_COOKIE_ECHOED)
+ first_len -= SCTP_ARBITRARY_COOKIE_ECHO_LEN;
+
+ /* Account for a different sized first fragment */
+ if (msg_len >= first_len) {
+ msg->can_delay = 0;
+ if (msg_len > first_len)
+ SCTP_INC_STATS(asoc->base.net,
+ SCTP_MIB_FRAGUSRMSGS);
+ } else {
+ /* Which may be the only one... */
+ first_len = msg_len;
+ }
+
+ /* Create chunks for all DATA chunks. */
+ for (remaining = msg_len; remaining; remaining -= len) {
+ u8 frag = SCTP_DATA_MIDDLE_FRAG;
+
+ if (remaining == msg_len) {
+ /* First frag, which may also be the last */
+ frag |= SCTP_DATA_FIRST_FRAG;
+ len = first_len;
+ } else {
+ /* Middle frags */
+ len = max_data;
+ }
+
+ if (len >= remaining) {
+ /* Last frag, which may also be the first */
+ len = remaining;
+ frag |= SCTP_DATA_LAST_FRAG;
+
+ /* The application requests to set the I-bit of the
+ * last DATA chunk of a user message when providing
+ * the user message to the SCTP implementation.
+ */
+ if ((sinfo->sinfo_flags & SCTP_EOF) ||
+ (sinfo->sinfo_flags & SCTP_SACK_IMMEDIATELY))
+ frag |= SCTP_DATA_SACK_IMM;
+ }
+
+ chunk = asoc->stream.si->make_datafrag(asoc, sinfo, len, frag,
+ GFP_KERNEL);
+ if (!chunk) {
+ err = -ENOMEM;
+ goto errout;
+ }
+
+ err = sctp_user_addto_chunk(chunk, len, from);
+ if (err < 0)
+ goto errout_chunk_free;
+
+ chunk->shkey = shkey;
+
+ /* Put the chunk->skb back into the form expected by send. */
+ __skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr -
+ chunk->skb->data);
+
+ sctp_datamsg_assign(msg, chunk);
+ list_add_tail(&chunk->frag_list, &msg->chunks);
+ }
+
+ return msg;
+
+errout_chunk_free:
+ sctp_chunk_free(chunk);
+
+errout:
+ list_for_each_safe(pos, temp, &msg->chunks) {
+ list_del_init(pos);
+ chunk = list_entry(pos, struct sctp_chunk, frag_list);
+ sctp_chunk_free(chunk);
+ }
+ sctp_datamsg_put(msg);
+
+ return ERR_PTR(err);
+}
+
+/* Check whether this message has expired. */
+int sctp_chunk_abandoned(struct sctp_chunk *chunk)
+{
+ if (!chunk->asoc->peer.prsctp_capable)
+ return 0;
+
+ if (chunk->msg->abandoned)
+ return 1;
+
+ if (!chunk->has_tsn &&
+ !(chunk->chunk_hdr->flags & SCTP_DATA_FIRST_FRAG))
+ return 0;
+
+ if (SCTP_PR_TTL_ENABLED(chunk->sinfo.sinfo_flags) &&
+ time_after(jiffies, chunk->msg->expires_at)) {
+ struct sctp_stream_out *streamout =
+ SCTP_SO(&chunk->asoc->stream,
+ chunk->sinfo.sinfo_stream);
+
+ if (chunk->sent_count) {
+ chunk->asoc->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
+ streamout->ext->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
+ } else {
+ chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
+ streamout->ext->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
+ }
+ chunk->msg->abandoned = 1;
+ return 1;
+ } else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&
+ chunk->sent_count > chunk->sinfo.sinfo_timetolive) {
+ struct sctp_stream_out *streamout =
+ SCTP_SO(&chunk->asoc->stream,
+ chunk->sinfo.sinfo_stream);
+
+ chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
+ streamout->ext->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
+ chunk->msg->abandoned = 1;
+ return 1;
+ } else if (!SCTP_PR_POLICY(chunk->sinfo.sinfo_flags) &&
+ chunk->msg->expires_at &&
+ time_after(jiffies, chunk->msg->expires_at)) {
+ chunk->msg->abandoned = 1;
+ return 1;
+ }
+ /* PRIO policy is processed by sendmsg, not here */
+
+ return 0;
+}
+
+/* This chunk (and consequently entire message) has failed in its sending. */
+void sctp_chunk_fail(struct sctp_chunk *chunk, int error)
+{
+ chunk->msg->send_failed = 1;
+ chunk->msg->send_error = error;
+}