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

1 files changed, 522 insertions, 0 deletions

diff --git a/drivers/net/usb/net1080.c b/drivers/net/usb/net1080.c
new file mode 100644
index 000000000..19f6e1222
--- /dev/null
+++ b/drivers/net/usb/net1080.c
@@ -0,0 +1,522 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Net1080 based USB host-to-host cables
+ * Copyright (C) 2000-2005 by David Brownell
+ */
+
+// #define	DEBUG			// error path messages, extra info
+// #define	VERBOSE			// more; success messages
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/workqueue.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+#include <linux/slab.h>
+
+#include <linux/unaligned.h>
+
+
+/*
+ * Netchip 1080 driver ... http://www.netchip.com
+ * (Sept 2004:  End-of-life announcement has been sent.)
+ * Used in (some) LapLink cables
+ */
+
+#define frame_errors	data[1]
+
+/*
+ * NetChip framing of ethernet packets, supporting additional error
+ * checks for links that may drop bulk packets from inside messages.
+ * Odd USB length == always short read for last usb packet.
+ *	- nc_header
+ *	- Ethernet header (14 bytes)
+ *	- payload
+ *	- (optional padding byte, if needed so length becomes odd)
+ *	- nc_trailer
+ *
+ * This framing is to be avoided for non-NetChip devices.
+ */
+
+struct nc_header {		// packed:
+	__le16	hdr_len;		// sizeof nc_header (LE, all)
+	__le16	packet_len;		// payload size (including ethhdr)
+	__le16	packet_id;		// detects dropped packets
+#define MIN_HEADER	6
+
+	// all else is optional, and must start with:
+	// __le16	vendorId;	// from usb-if
+	// __le16	productId;
+} __packed;
+
+#define	PAD_BYTE	((unsigned char)0xAC)
+
+struct nc_trailer {
+	__le16	packet_id;
+} __packed;
+
+// packets may use FLAG_FRAMING_NC and optional pad
+#define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \
+				+ sizeof (struct ethhdr) \
+				+ (mtu) \
+				+ 1 \
+				+ sizeof (struct nc_trailer))
+
+#define MIN_FRAMED	FRAMED_SIZE(0)
+
+/* packets _could_ be up to 64KB... */
+#define NC_MAX_PACKET	32767
+
+
+/*
+ * Zero means no timeout; else, how long a 64 byte bulk packet may be queued
+ * before the hardware drops it.  If that's done, the driver will need to
+ * frame network packets to guard against the dropped USB packets.  The win32
+ * driver sets this for both sides of the link.
+ */
+#define	NC_READ_TTL_MS	((u8)255)	// ms
+
+/*
+ * We ignore most registers and EEPROM contents.
+ */
+#define	REG_USBCTL	((u8)0x04)
+#define REG_TTL		((u8)0x10)
+#define REG_STATUS	((u8)0x11)
+
+/*
+ * Vendor specific requests to read/write data
+ */
+#define	REQUEST_REGISTER	((u8)0x10)
+#define	REQUEST_EEPROM		((u8)0x11)
+
+static int
+nc_vendor_read(struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr)
+{
+	int status = usbnet_read_cmd(dev, req,
+				     USB_DIR_IN | USB_TYPE_VENDOR |
+				     USB_RECIP_DEVICE,
+				     0, regnum, retval_ptr,
+				     sizeof *retval_ptr);
+	if (status > 0)
+		status = 0;
+	if (!status)
+		le16_to_cpus(retval_ptr);
+	return status;
+}
+
+static inline int
+nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr)
+{
+	return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr);
+}
+
+static void
+nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value)
+{
+	usbnet_write_cmd(dev, req,
+			 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+			 value, regnum, NULL, 0);
+}
+
+static inline void
+nc_register_write(struct usbnet *dev, u8 regnum, u16 value)
+{
+	nc_vendor_write(dev, REQUEST_REGISTER, regnum, value);
+}
+
+
+#if 0
+static void nc_dump_registers(struct usbnet *dev)
+{
+	u8	reg;
+	u16	*vp = kmalloc(sizeof (u16));
+
+	if (!vp)
+		return;
+
+	netdev_dbg(dev->net, "registers:\n");
+	for (reg = 0; reg < 0x20; reg++) {
+		int retval;
+
+		// reading some registers is trouble
+		if (reg >= 0x08 && reg <= 0xf)
+			continue;
+		if (reg >= 0x12 && reg <= 0x1e)
+			continue;
+
+		retval = nc_register_read(dev, reg, vp);
+		if (retval < 0)
+			netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n",
+				   reg, retval);
+		else
+			netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp);
+	}
+	kfree(vp);
+}
+#endif
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Control register
+ */
+
+#define	USBCTL_WRITABLE_MASK	0x1f0f
+// bits 15-13 reserved, r/o
+#define	USBCTL_ENABLE_LANG	(1 << 12)
+#define	USBCTL_ENABLE_MFGR	(1 << 11)
+#define	USBCTL_ENABLE_PROD	(1 << 10)
+#define	USBCTL_ENABLE_SERIAL	(1 << 9)
+#define	USBCTL_ENABLE_DEFAULTS	(1 << 8)
+// bits 7-4 reserved, r/o
+#define	USBCTL_FLUSH_OTHER	(1 << 3)
+#define	USBCTL_FLUSH_THIS	(1 << 2)
+#define	USBCTL_DISCONN_OTHER	(1 << 1)
+#define	USBCTL_DISCONN_THIS	(1 << 0)
+
+static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl)
+{
+	netif_dbg(dev, link, dev->net,
+		  "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s; this%s%s; other%s%s; r/o 0x%x\n",
+		  dev->udev->bus->bus_name, dev->udev->devpath,
+		  usbctl,
+		  (usbctl & USBCTL_ENABLE_LANG) ? " lang" : "",
+		  (usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "",
+		  (usbctl & USBCTL_ENABLE_PROD) ? " prod" : "",
+		  (usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "",
+		  (usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "",
+
+		  (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "",
+		  (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "",
+
+		  (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "",
+		  (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "",
+
+		  usbctl & ~USBCTL_WRITABLE_MASK);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Status register
+ */
+
+#define	STATUS_PORT_A		(1 << 15)
+
+#define	STATUS_CONN_OTHER	(1 << 14)
+#define	STATUS_SUSPEND_OTHER	(1 << 13)
+#define	STATUS_MAILBOX_OTHER	(1 << 12)
+#define	STATUS_PACKETS_OTHER(n)	(((n) >> 8) & 0x03)
+
+#define	STATUS_CONN_THIS	(1 << 6)
+#define	STATUS_SUSPEND_THIS	(1 << 5)
+#define	STATUS_MAILBOX_THIS	(1 << 4)
+#define	STATUS_PACKETS_THIS(n)	(((n) >> 0) & 0x03)
+
+#define	STATUS_UNSPEC_MASK	0x0c8c
+#define	STATUS_NOISE_MASK 	((u16)~(0x0303|STATUS_UNSPEC_MASK))
+
+
+static inline void nc_dump_status(struct usbnet *dev, u16 status)
+{
+	netif_dbg(dev, link, dev->net,
+		  "net1080 %s-%s status 0x%x: this (%c) PKT=%d%s%s%s; other PKT=%d%s%s%s; unspec 0x%x\n",
+		  dev->udev->bus->bus_name, dev->udev->devpath,
+		  status,
+
+		  // XXX the packet counts don't seem right
+		  // (1 at reset, not 0); maybe UNSPEC too
+
+		  (status & STATUS_PORT_A) ? 'A' : 'B',
+		  STATUS_PACKETS_THIS(status),
+		  (status & STATUS_CONN_THIS) ? " CON" : "",
+		  (status & STATUS_SUSPEND_THIS) ? " SUS" : "",
+		  (status & STATUS_MAILBOX_THIS) ? " MBOX" : "",
+
+		  STATUS_PACKETS_OTHER(status),
+		  (status & STATUS_CONN_OTHER) ? " CON" : "",
+		  (status & STATUS_SUSPEND_OTHER) ? " SUS" : "",
+		  (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "",
+
+		  status & STATUS_UNSPEC_MASK);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * TTL register
+ */
+
+#define	TTL_OTHER(ttl)	(0x00ff & (ttl >> 8))
+#define MK_TTL(this,other)	((u16)(((other)<<8)|(0x00ff&(this))))
+
+/*-------------------------------------------------------------------------*/
+
+static int net1080_reset(struct usbnet *dev)
+{
+	u16		usbctl, status, ttl;
+	u16		vp;
+	int		retval;
+
+	// nc_dump_registers(dev);
+
+	if ((retval = nc_register_read(dev, REG_STATUS, &vp)) < 0) {
+		netdev_dbg(dev->net, "can't read %s-%s status: %d\n",
+			   dev->udev->bus->bus_name, dev->udev->devpath, retval);
+		goto done;
+	}
+	status = vp;
+	nc_dump_status(dev, status);
+
+	if ((retval = nc_register_read(dev, REG_USBCTL, &vp)) < 0) {
+		netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval);
+		goto done;
+	}
+	usbctl = vp;
+	nc_dump_usbctl(dev, usbctl);
+
+	nc_register_write(dev, REG_USBCTL,
+			USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER);
+
+	if ((retval = nc_register_read(dev, REG_TTL, &vp)) < 0) {
+		netdev_dbg(dev->net, "can't read TTL, %d\n", retval);
+		goto done;
+	}
+	ttl = vp;
+
+	nc_register_write(dev, REG_TTL,
+			MK_TTL(NC_READ_TTL_MS, TTL_OTHER(ttl)) );
+	netdev_dbg(dev->net, "assigned TTL, %d ms\n", NC_READ_TTL_MS);
+
+	netif_info(dev, link, dev->net, "port %c, peer %sconnected\n",
+		   (status & STATUS_PORT_A) ? 'A' : 'B',
+		   (status & STATUS_CONN_OTHER) ? "" : "dis");
+	retval = 0;
+
+done:
+	return retval;
+}
+
+static int net1080_check_connect(struct usbnet *dev)
+{
+	int			retval;
+	u16			status;
+	u16			vp;
+
+	retval = nc_register_read(dev, REG_STATUS, &vp);
+	status = vp;
+	if (retval != 0) {
+		netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval);
+		return retval;
+	}
+	if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER)
+		return -ENOLINK;
+	return 0;
+}
+
+static void nc_ensure_sync(struct usbnet *dev)
+{
+	if (++dev->frame_errors <= 5)
+		return;
+
+	if (usbnet_write_cmd_async(dev, REQUEST_REGISTER,
+					USB_DIR_OUT | USB_TYPE_VENDOR |
+					USB_RECIP_DEVICE,
+					USBCTL_FLUSH_THIS |
+					USBCTL_FLUSH_OTHER,
+					REG_USBCTL, NULL, 0))
+		return;
+
+	netif_dbg(dev, rx_err, dev->net,
+		  "flush net1080; too many framing errors\n");
+	dev->frame_errors = 0;
+}
+
+static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+{
+	struct nc_header	*header;
+	struct nc_trailer	*trailer;
+	u16			hdr_len, packet_len;
+
+	/* This check is no longer done by usbnet */
+	if (skb->len < dev->net->hard_header_len)
+		return 0;
+
+	if (!(skb->len & 0x01)) {
+		netdev_dbg(dev->net, "rx framesize %d range %d..%d mtu %d\n",
+			   skb->len, dev->net->hard_header_len, dev->hard_mtu,
+			   dev->net->mtu);
+		dev->net->stats.rx_frame_errors++;
+		nc_ensure_sync(dev);
+		return 0;
+	}
+
+	header = (struct nc_header *) skb->data;
+	hdr_len = le16_to_cpup(&header->hdr_len);
+	packet_len = le16_to_cpup(&header->packet_len);
+	if (FRAMED_SIZE(packet_len) > NC_MAX_PACKET) {
+		dev->net->stats.rx_frame_errors++;
+		netdev_dbg(dev->net, "packet too big, %d\n", packet_len);
+		nc_ensure_sync(dev);
+		return 0;
+	} else if (hdr_len < MIN_HEADER) {
+		dev->net->stats.rx_frame_errors++;
+		netdev_dbg(dev->net, "header too short, %d\n", hdr_len);
+		nc_ensure_sync(dev);
+		return 0;
+	} else if (hdr_len > MIN_HEADER) {
+		// out of band data for us?
+		netdev_dbg(dev->net, "header OOB, %d bytes\n", hdr_len - MIN_HEADER);
+		nc_ensure_sync(dev);
+		// switch (vendor/product ids) { ... }
+	}
+	skb_pull(skb, hdr_len);
+
+	trailer = (struct nc_trailer *)
+		(skb->data + skb->len - sizeof *trailer);
+	skb_trim(skb, skb->len - sizeof *trailer);
+
+	if ((packet_len & 0x01) == 0) {
+		if (packet_len >= skb->len || skb->data[packet_len] != PAD_BYTE) {
+			dev->net->stats.rx_frame_errors++;
+			netdev_dbg(dev->net, "bad pad\n");
+			return 0;
+		}
+		skb_trim(skb, skb->len - 1);
+	}
+	if (skb->len != packet_len) {
+		dev->net->stats.rx_frame_errors++;
+		netdev_dbg(dev->net, "bad packet len %d (expected %d)\n",
+			   skb->len, packet_len);
+		nc_ensure_sync(dev);
+		return 0;
+	}
+	if (header->packet_id != get_unaligned(&trailer->packet_id)) {
+		dev->net->stats.rx_fifo_errors++;
+		netdev_dbg(dev->net, "(2+ dropped) rx packet_id mismatch 0x%x 0x%x\n",
+			   le16_to_cpu(header->packet_id),
+			   le16_to_cpu(trailer->packet_id));
+		return 0;
+	}
+#if 0
+	netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len,
+		   header->packet_len, header->packet_id);
+#endif
+	dev->frame_errors = 0;
+	return 1;
+}
+
+static struct sk_buff *
+net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
+{
+	struct sk_buff		*skb2;
+	struct nc_header	*header = NULL;
+	struct nc_trailer	*trailer = NULL;
+	int			padlen = sizeof (struct nc_trailer);
+	int			len = skb->len;
+
+	if (!((len + padlen + sizeof (struct nc_header)) & 0x01))
+		padlen++;
+	if (!skb_cloned(skb)) {
+		int	headroom = skb_headroom(skb);
+		int	tailroom = skb_tailroom(skb);
+
+		if (padlen <= tailroom &&
+		    sizeof(struct nc_header) <= headroom)
+			/* There's enough head and tail room */
+			goto encapsulate;
+
+		if ((sizeof (struct nc_header) + padlen) <
+				(headroom + tailroom)) {
+			/* There's enough total room, so just readjust */
+			skb->data = memmove(skb->head
+						+ sizeof (struct nc_header),
+					    skb->data, skb->len);
+			skb_set_tail_pointer(skb, len);
+			goto encapsulate;
+		}
+	}
+
+	/* Create a new skb to use with the correct size */
+	skb2 = skb_copy_expand(skb,
+				sizeof (struct nc_header),
+				padlen,
+				flags);
+	dev_kfree_skb_any(skb);
+	if (!skb2)
+		return skb2;
+	skb = skb2;
+
+encapsulate:
+	/* header first */
+	header = skb_push(skb, sizeof *header);
+	header->hdr_len = cpu_to_le16(sizeof (*header));
+	header->packet_len = cpu_to_le16(len);
+	header->packet_id = cpu_to_le16((u16)dev->xid++);
+
+	/* maybe pad; then trailer */
+	if (!((skb->len + sizeof *trailer) & 0x01))
+		skb_put_u8(skb, PAD_BYTE);
+	trailer = skb_put(skb, sizeof *trailer);
+	put_unaligned(header->packet_id, &trailer->packet_id);
+#if 0
+	netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n",
+		   header->hdr_len, header->packet_len,
+		   header->packet_id);
+#endif
+	return skb;
+}
+
+static int net1080_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+	unsigned	extra = sizeof (struct nc_header)
+				+ 1
+				+ sizeof (struct nc_trailer);
+
+	dev->net->hard_header_len += extra;
+	dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu;
+	dev->hard_mtu = NC_MAX_PACKET;
+	return usbnet_get_endpoints (dev, intf);
+}
+
+static const struct driver_info	net1080_info = {
+	.description =	"NetChip TurboCONNECT",
+	.flags =	FLAG_POINTTOPOINT | FLAG_FRAMING_NC,
+	.bind =		net1080_bind,
+	.reset =	net1080_reset,
+	.check_connect = net1080_check_connect,
+	.rx_fixup =	net1080_rx_fixup,
+	.tx_fixup =	net1080_tx_fixup,
+};
+
+static const struct usb_device_id	products [] = {
+{
+	USB_DEVICE(0x0525, 0x1080),	// NetChip ref design
+	.driver_info =	(unsigned long) &net1080_info,
+}, {
+	USB_DEVICE(0x06D0, 0x0622),	// Laplink Gold
+	.driver_info =	(unsigned long) &net1080_info,
+},
+	{ },		// END
+};
+MODULE_DEVICE_TABLE(usb, products);
+
+static struct usb_driver net1080_driver = {
+	.name =		"net1080",
+	.id_table =	products,
+	.probe =	usbnet_probe,
+	.disconnect =	usbnet_disconnect,
+	.suspend =	usbnet_suspend,
+	.resume =	usbnet_resume,
+	.disable_hub_initiated_lpm = 1,
+};
+
+module_usb_driver(net1080_driver);
+
+MODULE_AUTHOR("David Brownell");
+MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links");
+MODULE_LICENSE("GPL");