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, 401 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_common.c b/drivers/scsi/scsi_common.c
new file mode 100644
index 000000000..e1a2a62b6
--- /dev/null
+++ b/drivers/scsi/scsi_common.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SCSI functions used by both the initiator and the target code.
+ */
+
+#include <linux/bug.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <uapi/linux/pr.h>
+#include <linux/unaligned.h>
+#include <scsi/scsi_common.h>
+
+MODULE_DESCRIPTION("SCSI functions used by both the initiator and the target code");
+MODULE_LICENSE("GPL v2");
+
+/* Command group 3 is reserved and should never be used.  */
+const unsigned char scsi_command_size_tbl[8] = {
+	6, 10, 10, 12, 16, 12, 10, 10
+};
+EXPORT_SYMBOL(scsi_command_size_tbl);
+
+/* NB: These are exposed through /proc/scsi/scsi and form part of the ABI.
+ * You may not alter any existing entry (although adding new ones is
+ * encouraged once assigned by ANSI/INCITS T10).
+ */
+static const char *const scsi_device_types[] = {
+	"Direct-Access    ",
+	"Sequential-Access",
+	"Printer          ",
+	"Processor        ",
+	"WORM             ",
+	"CD-ROM           ",
+	"Scanner          ",
+	"Optical Device   ",
+	"Medium Changer   ",
+	"Communications   ",
+	"ASC IT8          ",
+	"ASC IT8          ",
+	"RAID             ",
+	"Enclosure        ",
+	"Direct-Access-RBC",
+	"Optical card     ",
+	"Bridge controller",
+	"Object storage   ",
+	"Automation/Drive ",
+	"Security Manager ",
+	"Direct-Access-ZBC",
+};
+
+/**
+ * scsi_device_type - Return 17-char string indicating device type.
+ * @type: type number to look up
+ */
+const char *scsi_device_type(unsigned type)
+{
+	if (type == 0x1e)
+		return "Well-known LUN   ";
+	if (type == 0x1f)
+		return "No Device        ";
+	if (type >= ARRAY_SIZE(scsi_device_types))
+		return "Unknown          ";
+	return scsi_device_types[type];
+}
+EXPORT_SYMBOL(scsi_device_type);
+
+enum pr_type scsi_pr_type_to_block(enum scsi_pr_type type)
+{
+	switch (type) {
+	case SCSI_PR_WRITE_EXCLUSIVE:
+		return PR_WRITE_EXCLUSIVE;
+	case SCSI_PR_EXCLUSIVE_ACCESS:
+		return PR_EXCLUSIVE_ACCESS;
+	case SCSI_PR_WRITE_EXCLUSIVE_REG_ONLY:
+		return PR_WRITE_EXCLUSIVE_REG_ONLY;
+	case SCSI_PR_EXCLUSIVE_ACCESS_REG_ONLY:
+		return PR_EXCLUSIVE_ACCESS_REG_ONLY;
+	case SCSI_PR_WRITE_EXCLUSIVE_ALL_REGS:
+		return PR_WRITE_EXCLUSIVE_ALL_REGS;
+	case SCSI_PR_EXCLUSIVE_ACCESS_ALL_REGS:
+		return PR_EXCLUSIVE_ACCESS_ALL_REGS;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(scsi_pr_type_to_block);
+
+enum scsi_pr_type block_pr_type_to_scsi(enum pr_type type)
+{
+	switch (type) {
+	case PR_WRITE_EXCLUSIVE:
+		return SCSI_PR_WRITE_EXCLUSIVE;
+	case PR_EXCLUSIVE_ACCESS:
+		return SCSI_PR_EXCLUSIVE_ACCESS;
+	case PR_WRITE_EXCLUSIVE_REG_ONLY:
+		return SCSI_PR_WRITE_EXCLUSIVE_REG_ONLY;
+	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
+		return SCSI_PR_EXCLUSIVE_ACCESS_REG_ONLY;
+	case PR_WRITE_EXCLUSIVE_ALL_REGS:
+		return SCSI_PR_WRITE_EXCLUSIVE_ALL_REGS;
+	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
+		return SCSI_PR_EXCLUSIVE_ACCESS_ALL_REGS;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(block_pr_type_to_scsi);
+
+/**
+ * scsilun_to_int - convert a scsi_lun to an int
+ * @scsilun:	struct scsi_lun to be converted.
+ *
+ * Description:
+ *     Convert @scsilun from a struct scsi_lun to a four-byte host byte-ordered
+ *     integer, and return the result. The caller must check for
+ *     truncation before using this function.
+ *
+ * Notes:
+ *     For a description of the LUN format, post SCSI-3 see the SCSI
+ *     Architecture Model, for SCSI-3 see the SCSI Controller Commands.
+ *
+ *     Given a struct scsi_lun of: d2 04 0b 03 00 00 00 00, this function
+ *     returns the integer: 0x0b03d204
+ *
+ *     This encoding will return a standard integer LUN for LUNs smaller
+ *     than 256, which typically use a single level LUN structure with
+ *     addressing method 0.
+ */
+u64 scsilun_to_int(struct scsi_lun *scsilun)
+{
+	int i;
+	u64 lun;
+
+	lun = 0;
+	for (i = 0; i < sizeof(lun); i += 2)
+		lun = lun | (((u64)scsilun->scsi_lun[i] << ((i + 1) * 8)) |
+			     ((u64)scsilun->scsi_lun[i + 1] << (i * 8)));
+	return lun;
+}
+EXPORT_SYMBOL(scsilun_to_int);
+
+/**
+ * int_to_scsilun - reverts an int into a scsi_lun
+ * @lun:        integer to be reverted
+ * @scsilun:	struct scsi_lun to be set.
+ *
+ * Description:
+ *     Reverts the functionality of the scsilun_to_int, which packed
+ *     an 8-byte lun value into an int. This routine unpacks the int
+ *     back into the lun value.
+ *
+ * Notes:
+ *     Given an integer : 0x0b03d204, this function returns a
+ *     struct scsi_lun of: d2 04 0b 03 00 00 00 00
+ *
+ */
+void int_to_scsilun(u64 lun, struct scsi_lun *scsilun)
+{
+	int i;
+
+	memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
+
+	for (i = 0; i < sizeof(lun); i += 2) {
+		scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
+		scsilun->scsi_lun[i+1] = lun & 0xFF;
+		lun = lun >> 16;
+	}
+}
+EXPORT_SYMBOL(int_to_scsilun);
+
+/**
+ * scsi_normalize_sense - normalize main elements from either fixed or
+ *			descriptor sense data format into a common format.
+ *
+ * @sense_buffer:	byte array containing sense data returned by device
+ * @sb_len:		number of valid bytes in sense_buffer
+ * @sshdr:		pointer to instance of structure that common
+ *			elements are written to.
+ *
+ * Notes:
+ *	The "main elements" from sense data are: response_code, sense_key,
+ *	asc, ascq and additional_length (only for descriptor format).
+ *
+ *	Typically this function can be called after a device has
+ *	responded to a SCSI command with the CHECK_CONDITION status.
+ *
+ * Return value:
+ *	true if valid sense data information found, else false;
+ */
+bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
+			  struct scsi_sense_hdr *sshdr)
+{
+	memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
+
+	if (!sense_buffer || !sb_len)
+		return false;
+
+	sshdr->response_code = (sense_buffer[0] & 0x7f);
+
+	if (!scsi_sense_valid(sshdr))
+		return false;
+
+	if (sshdr->response_code >= 0x72) {
+		/*
+		 * descriptor format
+		 */
+		if (sb_len > 1)
+			sshdr->sense_key = (sense_buffer[1] & 0xf);
+		if (sb_len > 2)
+			sshdr->asc = sense_buffer[2];
+		if (sb_len > 3)
+			sshdr->ascq = sense_buffer[3];
+		if (sb_len > 7)
+			sshdr->additional_length = sense_buffer[7];
+	} else {
+		/*
+		 * fixed format
+		 */
+		if (sb_len > 2)
+			sshdr->sense_key = (sense_buffer[2] & 0xf);
+		if (sb_len > 7) {
+			sb_len = min(sb_len, sense_buffer[7] + 8);
+			if (sb_len > 12)
+				sshdr->asc = sense_buffer[12];
+			if (sb_len > 13)
+				sshdr->ascq = sense_buffer[13];
+		}
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(scsi_normalize_sense);
+
+/**
+ * scsi_sense_desc_find - search for a given descriptor type in	descriptor sense data format.
+ * @sense_buffer:	byte array of descriptor format sense data
+ * @sb_len:		number of valid bytes in sense_buffer
+ * @desc_type:		value of descriptor type to find
+ *			(e.g. 0 -> information)
+ *
+ * Notes:
+ *	only valid when sense data is in descriptor format
+ *
+ * Return value:
+ *	pointer to start of (first) descriptor if found else NULL
+ */
+const u8 * scsi_sense_desc_find(const u8 * sense_buffer, int sb_len,
+				int desc_type)
+{
+	int add_sen_len, add_len, desc_len, k;
+	const u8 * descp;
+
+	if ((sb_len < 8) || (0 == (add_sen_len = sense_buffer[7])))
+		return NULL;
+	if ((sense_buffer[0] < 0x72) || (sense_buffer[0] > 0x73))
+		return NULL;
+	add_sen_len = (add_sen_len < (sb_len - 8)) ?
+			add_sen_len : (sb_len - 8);
+	descp = &sense_buffer[8];
+	for (desc_len = 0, k = 0; k < add_sen_len; k += desc_len) {
+		descp += desc_len;
+		add_len = (k < (add_sen_len - 1)) ? descp[1]: -1;
+		desc_len = add_len + 2;
+		if (descp[0] == desc_type)
+			return descp;
+		if (add_len < 0) // short descriptor ??
+			break;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(scsi_sense_desc_find);
+
+/**
+ * scsi_build_sense_buffer - build sense data in a buffer
+ * @desc:	Sense format (non-zero == descriptor format,
+ *              0 == fixed format)
+ * @buf:	Where to build sense data
+ * @key:	Sense key
+ * @asc:	Additional sense code
+ * @ascq:	Additional sense code qualifier
+ *
+ **/
+void scsi_build_sense_buffer(int desc, u8 *buf, u8 key, u8 asc, u8 ascq)
+{
+	if (desc) {
+		buf[0] = 0x72;	/* descriptor, current */
+		buf[1] = key;
+		buf[2] = asc;
+		buf[3] = ascq;
+		buf[7] = 0;
+	} else {
+		buf[0] = 0x70;	/* fixed, current */
+		buf[2] = key;
+		buf[7] = 0xa;
+		buf[12] = asc;
+		buf[13] = ascq;
+	}
+}
+EXPORT_SYMBOL(scsi_build_sense_buffer);
+
+/**
+ * scsi_set_sense_information - set the information field in a
+ *		formatted sense data buffer
+ * @buf:	Where to build sense data
+ * @buf_len:    buffer length
+ * @info:	64-bit information value to be set
+ *
+ * Return value:
+ *	0 on success or -EINVAL for invalid sense buffer length
+ **/
+int scsi_set_sense_information(u8 *buf, int buf_len, u64 info)
+{
+	if ((buf[0] & 0x7f) == 0x72) {
+		u8 *ucp, len;
+
+		len = buf[7];
+		ucp = (char *)scsi_sense_desc_find(buf, len + 8, 0);
+		if (!ucp) {
+			buf[7] = len + 0xc;
+			ucp = buf + 8 + len;
+		}
+
+		if (buf_len < len + 0xc)
+			/* Not enough room for info */
+			return -EINVAL;
+
+		ucp[0] = 0;
+		ucp[1] = 0xa;
+		ucp[2] = 0x80; /* Valid bit */
+		ucp[3] = 0;
+		put_unaligned_be64(info, &ucp[4]);
+	} else if ((buf[0] & 0x7f) == 0x70) {
+		/*
+		 * Only set the 'VALID' bit if we can represent the value
+		 * correctly; otherwise just fill out the lower bytes and
+		 * clear the 'VALID' flag.
+		 */
+		if (info <= 0xffffffffUL)
+			buf[0] |= 0x80;
+		else
+			buf[0] &= 0x7f;
+		put_unaligned_be32((u32)info, &buf[3]);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(scsi_set_sense_information);
+
+/**
+ * scsi_set_sense_field_pointer - set the field pointer sense key
+ *		specific information in a formatted sense data buffer
+ * @buf:	Where to build sense data
+ * @buf_len:    buffer length
+ * @fp:		field pointer to be set
+ * @bp:		bit pointer to be set
+ * @cd:		command/data bit
+ *
+ * Return value:
+ *	0 on success or -EINVAL for invalid sense buffer length
+ */
+int scsi_set_sense_field_pointer(u8 *buf, int buf_len, u16 fp, u8 bp, bool cd)
+{
+	u8 *ucp, len;
+
+	if ((buf[0] & 0x7f) == 0x72) {
+		len = buf[7];
+		ucp = (char *)scsi_sense_desc_find(buf, len + 8, 2);
+		if (!ucp) {
+			buf[7] = len + 8;
+			ucp = buf + 8 + len;
+		}
+
+		if (buf_len < len + 8)
+			/* Not enough room for info */
+			return -EINVAL;
+
+		ucp[0] = 2;
+		ucp[1] = 6;
+		ucp[4] = 0x80; /* Valid bit */
+		if (cd)
+			ucp[4] |= 0x40;
+		if (bp < 0x8)
+			ucp[4] |= 0x8 | bp;
+		put_unaligned_be16(fp, &ucp[5]);
+	} else if ((buf[0] & 0x7f) == 0x70) {
+		len = buf[7];
+		if (len < 18)
+			buf[7] = 18;
+
+		buf[15] = 0x80;
+		if (cd)
+			buf[15] |= 0x40;
+		if (bp < 0x8)
+			buf[15] |= 0x8 | bp;
+		put_unaligned_be16(fp, &buf[16]);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(scsi_set_sense_field_pointer);