diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
| commit | 034dd340b08be1f2f0477ad16131d609f9dbd53c (patch) | |
| tree | 2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/net/arcnet/rfc1201.c | |
| download | linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip | |
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt:
- Fix error output of boot instance creation failure
Currently if a boot instance creation fails, instead of printing out
the name of the instance that failed, it prints "(null)". That is
because it prints "cur_str" that had already been processed by
strsep(). Print the saved name instead.
While at it, print the error code of the failure.
- Fix use-after-free for same named historgrams
Histograms can be named so that they can be used in multiple events.
But if the named histogram has a variable attached, the second event
that uses the named histogram which duplicates it and needs to free
the original after duplication leaves the old variable in place and
still visible. If another histogram uses than variable, it will use
the stale one which will try to reference the freed duplicate
histogram and crash the kernel.
Free the duplicate variables along with the duplicated histogram
data.
- Check return value of kthread_run() in event self test
The events self tests uses a kthread for testing but does not check
if it succeeded in creating a kthread. If the kthread creation were
to fail, the code will still try to call kthread_stop() on the error
returned.
- Fix race between reading trace_pipe and updating subbuffer size
If a user is reading the trace_pipe file at the same time they update
the ring buffer sub-buffer size, can cause the trace_pipe read to
read stale data. Add trace_access_lock() around updating the ring
buffer sub-buffer size.
- Fix eventfs_inode on failure path in creation of the events directory
In the creation of the "events" directory, if after allocating the
eventfs_inode a failure is detected, it calls cleanup_ei() which
calls free_ei(). The free_ei() will test if eventfs_inode being freed
has no children. It is a bug if it does. But on the failure case of
the creation of the "events" directory, the children lists have not
yet been initialized and the free will trigger a warning because
list_empty() on an uninitialized list returns false.
Move the initialization into init_ei() where it makes more sense and
makes sure that a created eventfs_inode has its lists initialized
upon creation.
- Check return value of kthread_run() in ftrace direct sample code
The sample code that shows how to use the ftrace direct calls does
not test the return of kthread_run() to see if it succeeds. Return a
failure if the kthread_run() doesn't succeed.
- Clear user events state on fork in case of alloc failure
On fork, the child gets a pointer to the parent's user events state.
It makes a copy of it then updates the child's pointer to it. But if
the allocation fails, the duplication function leaves the child with
a pointer to its parent's descriptor. When the child cleans up its
data, it will free the parent's descriptor while the parent is still
using it.
In the duplication function, set the child's user_event_mm to NULL
before testing if the allocation succeeded, and when it exits it will
not free the parent's descriptor.
- Fix retry exhaustion in simple ring buffer reader swap
simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
post-decrements it only after a failed link replacement. On the final
attempt, a successful replacement leaves retry at zero, while a
failed replacement leaves it at -1.
But the check for success expects the retry value to be non-zero and
exits with an error on zero. This is the opposite result. Fix it.
- Fail nicely when the remote swap_reader_page() returns an error
Currently, if the swap_reader_page() of a remote buffer fails, it
triggers a WARN_ON_ONCE() and continues normally. Instead, have it
exit with an error and a pr_warn() print instead of a full WARNING.
* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Stop remote reader update when page swap fails
tracing: Fix retry exhaustion in simple ring buffer reader swap
tracing/user_events: Clear copied tracing state before fork duplication
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
eventfs: Initialize ei->children and ei->list in init_ei()
tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
tracing: Fix crash passing ERR_PTR to kthread_stop()
tracing: Fix use-after-free with same-name named triggers
tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/net/arcnet/rfc1201.c')
| -rw-r--r-- | drivers/net/arcnet/rfc1201.c | 548 |
1 files changed, 548 insertions, 0 deletions
diff --git a/drivers/net/arcnet/rfc1201.c b/drivers/net/arcnet/rfc1201.c new file mode 100644 index 000000000..f2ec58d06 --- /dev/null +++ b/drivers/net/arcnet/rfc1201.c @@ -0,0 +1,548 @@ +/* + * Linux ARCnet driver - RFC1201 (standard) packet encapsulation + * + * Written 1994-1999 by Avery Pennarun. + * Derived from skeleton.c by Donald Becker. + * + * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com) + * for sponsoring the further development of this driver. + * + * ********************** + * + * The original copyright of skeleton.c was as follows: + * + * skeleton.c Written 1993 by Donald Becker. + * Copyright 1993 United States Government as represented by the + * Director, National Security Agency. This software may only be used + * and distributed according to the terms of the GNU General Public License as + * modified by SRC, incorporated herein by reference. + * + * ********************** + * + * For more details, see drivers/net/arcnet.c + * + * ********************** + */ + +#define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt + +#include <linux/gfp.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/if_arp.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> + +#include "arcdevice.h" + +MODULE_DESCRIPTION("ARCNet packet format (RFC 1201) module"); +MODULE_LICENSE("GPL"); + +static __be16 type_trans(struct sk_buff *skb, struct net_device *dev); +static void rx(struct net_device *dev, int bufnum, + struct archdr *pkthdr, int length); +static int build_header(struct sk_buff *skb, struct net_device *dev, + unsigned short type, uint8_t daddr); +static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length, + int bufnum); +static int continue_tx(struct net_device *dev, int bufnum); + +static struct ArcProto rfc1201_proto = { + .suffix = 'a', + .mtu = 1500, /* could be more, but some receivers can't handle it... */ + .is_ip = 1, /* This is for sending IP and ARP packages */ + .rx = rx, + .build_header = build_header, + .prepare_tx = prepare_tx, + .continue_tx = continue_tx, + .ack_tx = NULL +}; + +static int __init arcnet_rfc1201_init(void) +{ + pr_info("%s\n", "RFC1201 \"standard\" (`a') encapsulation support loaded"); + + arc_proto_map[ARC_P_IP] + = arc_proto_map[ARC_P_IPV6] + = arc_proto_map[ARC_P_ARP] + = arc_proto_map[ARC_P_RARP] + = arc_proto_map[ARC_P_IPX] + = arc_proto_map[ARC_P_NOVELL_EC] + = &rfc1201_proto; + + /* if someone else already owns the broadcast, we won't take it */ + if (arc_bcast_proto == arc_proto_default) + arc_bcast_proto = &rfc1201_proto; + + return 0; +} + +static void __exit arcnet_rfc1201_exit(void) +{ + arcnet_unregister_proto(&rfc1201_proto); +} + +module_init(arcnet_rfc1201_init); +module_exit(arcnet_rfc1201_exit); + +/* Determine a packet's protocol ID. + * + * With ARCnet we have to convert everything to Ethernet-style stuff. + */ +static __be16 type_trans(struct sk_buff *skb, struct net_device *dev) +{ + struct archdr *pkt = (struct archdr *)skb->data; + struct arc_rfc1201 *soft = &pkt->soft.rfc1201; + int hdr_size = ARC_HDR_SIZE + RFC1201_HDR_SIZE; + + /* Pull off the arcnet header. */ + skb_reset_mac_header(skb); + skb_pull(skb, hdr_size); + + if (pkt->hard.dest == 0) { + skb->pkt_type = PACKET_BROADCAST; + } else if (dev->flags & IFF_PROMISC) { + /* if we're not sending to ourselves :) */ + if (pkt->hard.dest != dev->dev_addr[0]) + skb->pkt_type = PACKET_OTHERHOST; + } + /* now return the protocol number */ + switch (soft->proto) { + case ARC_P_IP: + return htons(ETH_P_IP); + case ARC_P_IPV6: + return htons(ETH_P_IPV6); + case ARC_P_ARP: + return htons(ETH_P_ARP); + case ARC_P_RARP: + return htons(ETH_P_RARP); + + case ARC_P_IPX: + case ARC_P_NOVELL_EC: + return htons(ETH_P_802_3); + default: + dev->stats.rx_errors++; + dev->stats.rx_crc_errors++; + return 0; + } + + return htons(ETH_P_IP); +} + +/* packet receiver */ +static void rx(struct net_device *dev, int bufnum, + struct archdr *pkthdr, int length) +{ + struct arcnet_local *lp = netdev_priv(dev); + struct sk_buff *skb; + struct archdr *pkt = pkthdr; + struct arc_rfc1201 *soft = &pkthdr->soft.rfc1201; + int saddr = pkt->hard.source, ofs; + struct Incoming *in = &lp->rfc1201.incoming[saddr]; + + arc_printk(D_DURING, dev, "it's an RFC1201 packet (length=%d)\n", + length); + + if (length >= MinTU) + ofs = 512 - length; + else + ofs = 256 - length; + + if (soft->split_flag == 0xFF) { /* Exception Packet */ + if (length >= 4 + RFC1201_HDR_SIZE) { + arc_printk(D_DURING, dev, "compensating for exception packet\n"); + } else { + arc_printk(D_EXTRA, dev, "short RFC1201 exception packet from %02Xh", + saddr); + return; + } + + /* skip over 4-byte junkola */ + length -= 4; + ofs += 4; + lp->hw.copy_from_card(dev, bufnum, 512 - length, + soft, sizeof(pkt->soft)); + } + if (!soft->split_flag) { /* not split */ + arc_printk(D_RX, dev, "incoming is not split (splitflag=%d)\n", + soft->split_flag); + + if (in->skb) { /* already assembling one! */ + arc_printk(D_EXTRA, dev, "aborting assembly (seq=%d) for unsplit packet (splitflag=%d, seq=%d)\n", + in->sequence, soft->split_flag, + soft->sequence); + lp->rfc1201.aborted_seq = soft->sequence; + dev_kfree_skb_irq(in->skb); + dev->stats.rx_errors++; + dev->stats.rx_missed_errors++; + in->skb = NULL; + } + in->sequence = soft->sequence; + + skb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC); + if (!skb) { + dev->stats.rx_dropped++; + return; + } + skb_put(skb, length + ARC_HDR_SIZE); + skb->dev = dev; + + pkt = (struct archdr *)skb->data; + soft = &pkt->soft.rfc1201; + + /* up to sizeof(pkt->soft) has already + * been copied from the card + */ + memcpy(pkt, pkthdr, sizeof(struct archdr)); + if (length > sizeof(pkt->soft)) + lp->hw.copy_from_card(dev, bufnum, + ofs + sizeof(pkt->soft), + pkt->soft.raw + sizeof(pkt->soft), + length - sizeof(pkt->soft)); + + /* ARP packets have problems when sent from some DOS systems: + * the source address is always 0! + * So we take the hardware source addr (which is impossible + * to fumble) and insert it ourselves. + */ + if (soft->proto == ARC_P_ARP) { + struct arphdr *arp = (struct arphdr *)soft->payload; + + /* make sure addresses are the right length */ + if (arp->ar_hln == 1 && arp->ar_pln == 4) { + uint8_t *cptr = (uint8_t *)arp + sizeof(struct arphdr); + + if (!*cptr) { /* is saddr = 00? */ + arc_printk(D_EXTRA, dev, + "ARP source address was 00h, set to %02Xh\n", + saddr); + dev->stats.rx_crc_errors++; + *cptr = saddr; + } else { + arc_printk(D_DURING, dev, "ARP source address (%Xh) is fine.\n", + *cptr); + } + } else { + arc_printk(D_NORMAL, dev, "funny-shaped ARP packet. (%Xh, %Xh)\n", + arp->ar_hln, arp->ar_pln); + dev->stats.rx_errors++; + dev->stats.rx_crc_errors++; + } + } + if (BUGLVL(D_SKB)) + arcnet_dump_skb(dev, skb, "rx"); + + skb->protocol = type_trans(skb, dev); + netif_rx(skb); + } else { /* split packet */ + /* NOTE: MS-DOS ARP packet correction should only need to + * apply to unsplit packets, since ARP packets are so short. + * + * My interpretation of the RFC1201 document is that if a + * packet is received out of order, the entire assembly + * process should be aborted. + * + * The RFC also mentions "it is possible for successfully + * received packets to be retransmitted." As of 0.40 all + * previously received packets are allowed, not just the + * most recent one. + * + * We allow multiple assembly processes, one for each + * ARCnet card possible on the network. + * Seems rather like a waste of memory, but there's no + * other way to be reliable. + */ + + arc_printk(D_RX, dev, "packet is split (splitflag=%d, seq=%d)\n", + soft->split_flag, in->sequence); + + if (in->skb && in->sequence != soft->sequence) { + arc_printk(D_EXTRA, dev, "wrong seq number (saddr=%d, expected=%d, seq=%d, splitflag=%d)\n", + saddr, in->sequence, soft->sequence, + soft->split_flag); + dev_kfree_skb_irq(in->skb); + in->skb = NULL; + dev->stats.rx_errors++; + dev->stats.rx_missed_errors++; + in->lastpacket = in->numpackets = 0; + } + if (soft->split_flag & 1) { /* first packet in split */ + arc_printk(D_RX, dev, "brand new splitpacket (splitflag=%d)\n", + soft->split_flag); + if (in->skb) { /* already assembling one! */ + arc_printk(D_EXTRA, dev, "aborting previous (seq=%d) assembly (splitflag=%d, seq=%d)\n", + in->sequence, soft->split_flag, + soft->sequence); + dev->stats.rx_errors++; + dev->stats.rx_missed_errors++; + dev_kfree_skb_irq(in->skb); + } + in->sequence = soft->sequence; + in->numpackets = ((unsigned)soft->split_flag >> 1) + 2; + in->lastpacket = 1; + + if (in->numpackets > 16) { + arc_printk(D_EXTRA, dev, "incoming packet more than 16 segments; dropping. (splitflag=%d)\n", + soft->split_flag); + lp->rfc1201.aborted_seq = soft->sequence; + dev->stats.rx_errors++; + dev->stats.rx_length_errors++; + return; + } + in->skb = skb = alloc_skb(508 * in->numpackets + ARC_HDR_SIZE, + GFP_ATOMIC); + if (!skb) { + arc_printk(D_NORMAL, dev, "(split) memory squeeze, dropping packet.\n"); + lp->rfc1201.aborted_seq = soft->sequence; + dev->stats.rx_dropped++; + return; + } + skb->dev = dev; + pkt = (struct archdr *)skb->data; + soft = &pkt->soft.rfc1201; + + memcpy(pkt, pkthdr, ARC_HDR_SIZE + RFC1201_HDR_SIZE); + skb_put(skb, ARC_HDR_SIZE + RFC1201_HDR_SIZE); + + soft->split_flag = 0; /* end result won't be split */ + } else { /* not first packet */ + int packetnum = ((unsigned)soft->split_flag >> 1) + 1; + + /* if we're not assembling, there's no point trying to + * continue. + */ + if (!in->skb) { + if (lp->rfc1201.aborted_seq != soft->sequence) { + arc_printk(D_EXTRA, dev, "can't continue split without starting first! (splitflag=%d, seq=%d, aborted=%d)\n", + soft->split_flag, + soft->sequence, + lp->rfc1201.aborted_seq); + dev->stats.rx_errors++; + dev->stats.rx_missed_errors++; + } + return; + } + in->lastpacket++; + /* if not the right flag */ + if (packetnum != in->lastpacket) { + /* harmless duplicate? ignore. */ + if (packetnum <= in->lastpacket - 1) { + arc_printk(D_EXTRA, dev, "duplicate splitpacket ignored! (splitflag=%d)\n", + soft->split_flag); + dev->stats.rx_errors++; + dev->stats.rx_frame_errors++; + return; + } + /* "bad" duplicate, kill reassembly */ + arc_printk(D_EXTRA, dev, "out-of-order splitpacket, reassembly (seq=%d) aborted (splitflag=%d, seq=%d)\n", + in->sequence, soft->split_flag, + soft->sequence); + lp->rfc1201.aborted_seq = soft->sequence; + dev_kfree_skb_irq(in->skb); + in->skb = NULL; + dev->stats.rx_errors++; + dev->stats.rx_missed_errors++; + in->lastpacket = in->numpackets = 0; + return; + } + pkt = (struct archdr *)in->skb->data; + soft = &pkt->soft.rfc1201; + } + + skb = in->skb; + + lp->hw.copy_from_card(dev, bufnum, ofs + RFC1201_HDR_SIZE, + skb->data + skb->len, + length - RFC1201_HDR_SIZE); + skb_put(skb, length - RFC1201_HDR_SIZE); + + /* are we done? */ + if (in->lastpacket == in->numpackets) { + in->skb = NULL; + in->lastpacket = in->numpackets = 0; + + arc_printk(D_SKB_SIZE, dev, "skb: received %d bytes from %02X (unsplit)\n", + skb->len, pkt->hard.source); + arc_printk(D_SKB_SIZE, dev, "skb: received %d bytes from %02X (split)\n", + skb->len, pkt->hard.source); + if (BUGLVL(D_SKB)) + arcnet_dump_skb(dev, skb, "rx"); + + skb->protocol = type_trans(skb, dev); + netif_rx(skb); + } + } +} + +/* Create the ARCnet hard/soft headers for RFC1201. */ +static int build_header(struct sk_buff *skb, struct net_device *dev, + unsigned short type, uint8_t daddr) +{ + struct arcnet_local *lp = netdev_priv(dev); + int hdr_size = ARC_HDR_SIZE + RFC1201_HDR_SIZE; + struct archdr *pkt = skb_push(skb, hdr_size); + struct arc_rfc1201 *soft = &pkt->soft.rfc1201; + + /* set the protocol ID according to RFC1201 */ + switch (type) { + case ETH_P_IP: + soft->proto = ARC_P_IP; + break; + case ETH_P_IPV6: + soft->proto = ARC_P_IPV6; + break; + case ETH_P_ARP: + soft->proto = ARC_P_ARP; + break; + case ETH_P_RARP: + soft->proto = ARC_P_RARP; + break; + case ETH_P_IPX: + case ETH_P_802_3: + case ETH_P_802_2: + soft->proto = ARC_P_IPX; + break; + case ETH_P_ATALK: + soft->proto = ARC_P_ATALK; + break; + default: + arc_printk(D_NORMAL, dev, "RFC1201: I don't understand protocol %d (%Xh)\n", + type, type); + dev->stats.tx_errors++; + dev->stats.tx_aborted_errors++; + return 0; + } + + /* Set the source hardware address. + * + * This is pretty pointless for most purposes, but it can help in + * debugging. ARCnet does not allow us to change the source address + * in the actual packet sent. + */ + pkt->hard.source = *dev->dev_addr; + + soft->sequence = htons(lp->rfc1201.sequence++); + soft->split_flag = 0; /* split packets are done elsewhere */ + + /* see linux/net/ethernet/eth.c to see where I got the following */ + + if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { + /* FIXME: fill in the last byte of the dest ipaddr here + * to better comply with RFC1051 in "noarp" mode. + * For now, always broadcasting will probably at least get + * packets sent out :) + */ + pkt->hard.dest = 0; + return hdr_size; + } + /* otherwise, drop in the dest address */ + pkt->hard.dest = daddr; + return hdr_size; +} + +static void load_pkt(struct net_device *dev, struct arc_hardware *hard, + struct arc_rfc1201 *soft, int softlen, int bufnum) +{ + struct arcnet_local *lp = netdev_priv(dev); + int ofs; + + /* assume length <= XMTU: someone should have handled that by now. */ + + if (softlen > MinTU) { + hard->offset[0] = 0; + hard->offset[1] = ofs = 512 - softlen; + } else if (softlen > MTU) { /* exception packet - add an extra header */ + struct arc_rfc1201 excsoft; + + excsoft.proto = soft->proto; + excsoft.split_flag = 0xff; + excsoft.sequence = htons(0xffff); + + hard->offset[0] = 0; + ofs = 512 - softlen; + hard->offset[1] = ofs - RFC1201_HDR_SIZE; + lp->hw.copy_to_card(dev, bufnum, ofs - RFC1201_HDR_SIZE, + &excsoft, RFC1201_HDR_SIZE); + } else { + hard->offset[0] = ofs = 256 - softlen; + } + + lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE); + lp->hw.copy_to_card(dev, bufnum, ofs, soft, softlen); + + lp->lastload_dest = hard->dest; +} + +static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length, + int bufnum) +{ + struct arcnet_local *lp = netdev_priv(dev); + const int maxsegsize = XMTU - RFC1201_HDR_SIZE; + struct Outgoing *out; + + arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n", + lp->next_tx, lp->cur_tx, bufnum); + + /* hard header is not included in packet length */ + length -= ARC_HDR_SIZE; + pkt->soft.rfc1201.split_flag = 0; + + /* need to do a split packet? */ + if (length > XMTU) { + out = &lp->outgoing; + + out->length = length - RFC1201_HDR_SIZE; + out->dataleft = lp->outgoing.length; + out->numsegs = (out->dataleft + maxsegsize - 1) / maxsegsize; + out->segnum = 0; + + arc_printk(D_DURING, dev, "rfc1201 prep_tx: ready for %d-segment split (%d bytes, seq=%d)\n", + out->numsegs, out->length, + pkt->soft.rfc1201.sequence); + + return 0; /* not done */ + } + /* just load the packet into the buffers and send it off */ + load_pkt(dev, &pkt->hard, &pkt->soft.rfc1201, length, bufnum); + + return 1; /* done */ +} + +static int continue_tx(struct net_device *dev, int bufnum) +{ + struct arcnet_local *lp = netdev_priv(dev); + struct Outgoing *out = &lp->outgoing; + struct arc_hardware *hard = &out->pkt->hard; + struct arc_rfc1201 *soft = &out->pkt->soft.rfc1201, *newsoft; + int maxsegsize = XMTU - RFC1201_HDR_SIZE; + int seglen; + + arc_printk(D_DURING, dev, + "rfc1201 continue_tx: loading segment %d(+1) of %d (seq=%d)\n", + out->segnum, out->numsegs, soft->sequence); + + /* the "new" soft header comes right before the data chunk */ + newsoft = (struct arc_rfc1201 *) + (out->pkt->soft.raw + out->length - out->dataleft); + + if (!out->segnum) /* first packet; newsoft == soft */ + newsoft->split_flag = ((out->numsegs - 2) << 1) | 1; + else { + newsoft->split_flag = out->segnum << 1; + newsoft->proto = soft->proto; + newsoft->sequence = soft->sequence; + } + + seglen = maxsegsize; + if (seglen > out->dataleft) + seglen = out->dataleft; + out->dataleft -= seglen; + + load_pkt(dev, hard, newsoft, seglen + RFC1201_HDR_SIZE, bufnum); + + out->segnum++; + if (out->segnum >= out->numsegs) + return 1; + else + return 0; +} |
