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, 454 insertions, 0 deletions

diff --git a/fs/smb/server/unicode.c b/fs/smb/server/unicode.c
new file mode 100644
index 000000000..85e679174
--- /dev/null
+++ b/fs/smb/server/unicode.c
@@ -0,0 +1,454 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Some of the source code in this file came from fs/cifs/cifs_unicode.c
+ *
+ *   Copyright (c) International Business Machines  Corp., 2000,2009
+ *   Modified by Steve French (sfrench@us.ibm.com)
+ *   Modified by Namjae Jeon (linkinjeon@kernel.org)
+ */
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/unaligned.h>
+#include "glob.h"
+#include "unicode.h"
+#include "smb_common.h"
+
+/*
+ * cifs_mapchar() - convert a host-endian char to proper char in codepage
+ * @target:	where converted character should be copied
+ * @from:	host-endian source string
+ * @cp:		codepage to which character should be converted
+ * @mapchar:	should character be mapped according to mapchars mount option?
+ *
+ * This function handles the conversion of a single character. It is the
+ * responsibility of the caller to ensure that the target buffer is large
+ * enough to hold the result of the conversion (at least NLS_MAX_CHARSET_SIZE).
+ *
+ * Return:	string length after conversion
+ */
+static int
+cifs_mapchar(char *target, const __u16 *from, const struct nls_table *cp,
+	     bool mapchar)
+{
+	int len = 1;
+	__u16 src_char;
+
+	src_char = *from;
+
+	if (!mapchar)
+		goto cp_convert;
+
+	/*
+	 * BB: Cannot handle remapping UNI_SLASH until all the calls to
+	 *     build_path_from_dentry are modified, as they use slash as
+	 *     separator.
+	 */
+	switch (src_char) {
+	case UNI_COLON:
+		*target = ':';
+		break;
+	case UNI_ASTERISK:
+		*target = '*';
+		break;
+	case UNI_QUESTION:
+		*target = '?';
+		break;
+	case UNI_PIPE:
+		*target = '|';
+		break;
+	case UNI_GRTRTHAN:
+		*target = '>';
+		break;
+	case UNI_LESSTHAN:
+		*target = '<';
+		break;
+	default:
+		goto cp_convert;
+	}
+
+out:
+	return len;
+
+cp_convert:
+	len = cp->uni2char(src_char, target, NLS_MAX_CHARSET_SIZE);
+	if (len <= 0)
+		goto surrogate_pair;
+
+	goto out;
+
+surrogate_pair:
+	/* convert SURROGATE_PAIR and IVS */
+	if (strcmp(cp->charset, "utf8"))
+		goto unknown;
+	len = utf16s_to_utf8s(from, 3, UTF16_LITTLE_ENDIAN, target, 6);
+	if (len <= 0)
+		goto unknown;
+	return len;
+
+unknown:
+	*target = '?';
+	len = 1;
+	goto out;
+}
+
+/*
+ * smb_utf16_bytes() - compute converted string length
+ * @from:	pointer to input string
+ * @maxbytes:	input string length
+ * @codepage:	destination codepage
+ *
+ * Walk a utf16le string and return the number of bytes that the string will
+ * be after being converted to the given charset, not including any null
+ * termination required. Don't walk past maxbytes in the source buffer.
+ *
+ * Return:	string length after conversion
+ */
+static int smb_utf16_bytes(const __le16 *from, int maxbytes,
+			   const struct nls_table *codepage)
+{
+	int i, j;
+	int charlen, outlen = 0;
+	int maxwords = maxbytes / 2;
+	char tmp[NLS_MAX_CHARSET_SIZE];
+	__u16 ftmp[3];
+
+	for (i = 0; i < maxwords; i++) {
+		ftmp[0] = get_unaligned_le16(&from[i]);
+		if (ftmp[0] == 0)
+			break;
+		for (j = 1; j <= 2; j++) {
+			if (i + j < maxwords)
+				ftmp[j] = get_unaligned_le16(&from[i + j]);
+			else
+				ftmp[j] = 0;
+		}
+
+		charlen = cifs_mapchar(tmp, ftmp, codepage, 0);
+		if (charlen > 0)
+			outlen += charlen;
+		else
+			outlen++;
+	}
+
+	return outlen;
+}
+
+/*
+ * smb_from_utf16() - convert utf16le string to local charset
+ * @to:		destination buffer
+ * @from:	source buffer
+ * @tolen:	destination buffer size (in bytes)
+ * @fromlen:	source buffer size (in bytes)
+ * @codepage:	codepage to which characters should be converted
+ * @mapchar:	should characters be remapped according to the mapchars option?
+ *
+ * Convert a little-endian utf16le string (as sent by the server) to a string
+ * in the provided codepage. The tolen and fromlen parameters are to ensure
+ * that the code doesn't walk off of the end of the buffer (which is always
+ * a danger if the alignment of the source buffer is off). The destination
+ * string is always properly null terminated and fits in the destination
+ * buffer. Returns the length of the destination string in bytes (including
+ * null terminator).
+ *
+ * Note that some windows versions actually send multiword UTF-16 characters
+ * instead of straight UTF16-2. The linux nls routines however aren't able to
+ * deal with those characters properly. In the event that we get some of
+ * those characters, they won't be translated properly.
+ *
+ * Return:	string length after conversion
+ */
+static int smb_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,
+			  const struct nls_table *codepage, bool mapchar)
+{
+	int i, j, charlen, safelen;
+	int outlen = 0;
+	int nullsize = nls_nullsize(codepage);
+	int fromwords = fromlen / 2;
+	char tmp[NLS_MAX_CHARSET_SIZE];
+	__u16 ftmp[3];	/* ftmp[3] = 3array x 2bytes = 6bytes UTF-16 */
+
+	/*
+	 * because the chars can be of varying widths, we need to take care
+	 * not to overflow the destination buffer when we get close to the
+	 * end of it. Until we get to this offset, we don't need to check
+	 * for overflow however.
+	 */
+	safelen = tolen - (NLS_MAX_CHARSET_SIZE + nullsize);
+
+	for (i = 0; i < fromwords; i++) {
+		ftmp[0] = get_unaligned_le16(&from[i]);
+		if (ftmp[0] == 0)
+			break;
+		for (j = 1; j <= 2; j++) {
+			if (i + j < fromwords)
+				ftmp[j] = get_unaligned_le16(&from[i + j]);
+			else
+				ftmp[j] = 0;
+		}
+
+		/*
+		 * check to see if converting this character might make the
+		 * conversion bleed into the null terminator
+		 */
+		if (outlen >= safelen) {
+			charlen = cifs_mapchar(tmp, ftmp, codepage, mapchar);
+			if ((outlen + charlen) > (tolen - nullsize))
+				break;
+		}
+
+		/* put converted char into 'to' buffer */
+		charlen = cifs_mapchar(&to[outlen], ftmp, codepage, mapchar);
+		outlen += charlen;
+
+		/*
+		 * charlen (=bytes of UTF-8 for 1 character)
+		 * 4bytes UTF-8(surrogate pair) is charlen=4
+		 * (4bytes UTF-16 code)
+		 * 7-8bytes UTF-8(IVS) is charlen=3+4 or 4+4
+		 * (2 UTF-8 pairs divided to 2 UTF-16 pairs)
+		 */
+		if (charlen == 4)
+			i++;
+		else if (charlen >= 5)
+			/* 5-6bytes UTF-8 */
+			i += 2;
+	}
+
+	/* properly null-terminate string */
+	for (i = 0; i < nullsize; i++)
+		to[outlen++] = 0;
+
+	return outlen;
+}
+
+/*
+ * smb_strtoUTF16() - Convert character string to unicode string
+ * @to:		destination buffer
+ * @from:	source buffer
+ * @len:	destination buffer size (in bytes)
+ * @codepage:	codepage to which characters should be converted
+ *
+ * Return:	string length after conversion
+ */
+int smb_strtoUTF16(__le16 *to, const char *from, int len,
+		   const struct nls_table *codepage)
+{
+	int charlen;
+	int i;
+	wchar_t wchar_to; /* needed to quiet sparse */
+
+	/* special case for utf8 to handle no plane0 chars */
+	if (!strcmp(codepage->charset, "utf8")) {
+		/*
+		 * convert utf8 -> utf16, we assume we have enough space
+		 * as caller should have assumed conversion does not overflow
+		 * in destination len is length in wchar_t units (16bits)
+		 */
+		i  = utf8s_to_utf16s(from, len, UTF16_LITTLE_ENDIAN,
+				     (wchar_t *)to, len);
+
+		/* if success terminate and exit */
+		if (i >= 0)
+			goto success;
+		/*
+		 * if fails fall back to UCS encoding as this
+		 * function should not return negative values
+		 * currently can fail only if source contains
+		 * invalid encoded characters
+		 */
+	}
+
+	for (i = 0; len > 0 && *from; i++, from += charlen, len -= charlen) {
+		charlen = codepage->char2uni(from, len, &wchar_to);
+		if (charlen < 1) {
+			/* A question mark */
+			wchar_to = 0x003f;
+			charlen = 1;
+		}
+		put_unaligned_le16(wchar_to, &to[i]);
+	}
+
+success:
+	put_unaligned_le16(0, &to[i]);
+	return i;
+}
+
+/*
+ * smb_strndup_from_utf16() - copy a string from wire format to the local
+ *		codepage
+ * @src:	source string
+ * @maxlen:	don't walk past this many bytes in the source string
+ * @is_unicode:	is this a unicode string?
+ * @codepage:	destination codepage
+ *
+ * Take a string given by the server, convert it to the local codepage and
+ * put it in a new buffer. Returns a pointer to the new string or NULL on
+ * error.
+ *
+ * Return:	destination string buffer or error ptr
+ */
+char *smb_strndup_from_utf16(const char *src, const int maxlen,
+			     const bool is_unicode,
+			     const struct nls_table *codepage)
+{
+	int len, ret;
+	char *dst;
+
+	if (is_unicode) {
+		len = smb_utf16_bytes((__le16 *)src, maxlen, codepage);
+		len += nls_nullsize(codepage);
+		dst = kmalloc(len, KSMBD_DEFAULT_GFP);
+		if (!dst)
+			return ERR_PTR(-ENOMEM);
+		ret = smb_from_utf16(dst, (__le16 *)src, len, maxlen, codepage,
+				     false);
+		if (ret < 0) {
+			kfree(dst);
+			return ERR_PTR(-EINVAL);
+		}
+	} else {
+		len = strnlen(src, maxlen);
+		len++;
+		dst = kmalloc(len, KSMBD_DEFAULT_GFP);
+		if (!dst)
+			return ERR_PTR(-ENOMEM);
+		strscpy(dst, src, len);
+	}
+
+	return dst;
+}
+
+/*
+ * Convert 16 bit Unicode pathname to wire format from string in current code
+ * page. Conversion may involve remapping up the six characters that are
+ * only legal in POSIX-like OS (if they are present in the string). Path
+ * names are little endian 16 bit Unicode on the wire
+ */
+/*
+ * smbConvertToUTF16() - convert string from local charset to utf16
+ * @target:	destination buffer
+ * @source:	source buffer
+ * @srclen:	source buffer size (in bytes)
+ * @cp:		codepage to which characters should be converted
+ * @mapchar:	should characters be remapped according to the mapchars option?
+ *
+ * Convert 16 bit Unicode pathname to wire format from string in current code
+ * page. Conversion may involve remapping up the six characters that are
+ * only legal in POSIX-like OS (if they are present in the string). Path
+ * names are little endian 16 bit Unicode on the wire
+ *
+ * Return:	char length after conversion
+ */
+int smbConvertToUTF16(__le16 *target, const char *source, int srclen,
+		      const struct nls_table *cp, int mapchars)
+{
+	int i, j, charlen;
+	char src_char;
+	__le16 dst_char;
+	wchar_t tmp;
+	wchar_t wchar_to[6];	/* UTF-16 */
+	int ret;
+	unicode_t u;
+
+	if (!mapchars)
+		return smb_strtoUTF16(target, source, srclen, cp);
+
+	for (i = 0, j = 0; i < srclen; j++) {
+		src_char = source[i];
+		charlen = 1;
+		switch (src_char) {
+		case 0:
+			put_unaligned(0, &target[j]);
+			return j;
+		case ':':
+			dst_char = cpu_to_le16(UNI_COLON);
+			break;
+		case '*':
+			dst_char = cpu_to_le16(UNI_ASTERISK);
+			break;
+		case '?':
+			dst_char = cpu_to_le16(UNI_QUESTION);
+			break;
+		case '<':
+			dst_char = cpu_to_le16(UNI_LESSTHAN);
+			break;
+		case '>':
+			dst_char = cpu_to_le16(UNI_GRTRTHAN);
+			break;
+		case '|':
+			dst_char = cpu_to_le16(UNI_PIPE);
+			break;
+		/*
+		 * FIXME: We can not handle remapping backslash (UNI_SLASH)
+		 * until all the calls to build_path_from_dentry are modified,
+		 * as they use backslash as separator.
+		 */
+		default:
+			charlen = cp->char2uni(source + i, srclen - i, &tmp);
+			dst_char = cpu_to_le16(tmp);
+
+			/*
+			 * if no match, use question mark, which at least in
+			 * some cases serves as wild card
+			 */
+			if (charlen > 0)
+				goto ctoUTF16;
+
+			/* convert SURROGATE_PAIR */
+			if (strcmp(cp->charset, "utf8"))
+				goto unknown;
+			if (*(source + i) & 0x80) {
+				charlen = utf8_to_utf32(source + i, 6, &u);
+				if (charlen < 0)
+					goto unknown;
+			} else
+				goto unknown;
+			ret  = utf8s_to_utf16s(source + i, charlen,
+					UTF16_LITTLE_ENDIAN,
+					wchar_to, 6);
+			if (ret < 0)
+				goto unknown;
+
+			i += charlen;
+			dst_char = cpu_to_le16(*wchar_to);
+			if (charlen <= 3)
+				/* 1-3bytes UTF-8 to 2bytes UTF-16 */
+				put_unaligned(dst_char, &target[j]);
+			else if (charlen == 4) {
+				/*
+				 * 4bytes UTF-8(surrogate pair) to 4bytes UTF-16
+				 * 7-8bytes UTF-8(IVS) divided to 2 UTF-16
+				 * (charlen=3+4 or 4+4)
+				 */
+				put_unaligned(dst_char, &target[j]);
+				dst_char = cpu_to_le16(*(wchar_to + 1));
+				j++;
+				put_unaligned(dst_char, &target[j]);
+			} else if (charlen >= 5) {
+				/* 5-6bytes UTF-8 to 6bytes UTF-16 */
+				put_unaligned(dst_char, &target[j]);
+				dst_char = cpu_to_le16(*(wchar_to + 1));
+				j++;
+				put_unaligned(dst_char, &target[j]);
+				dst_char = cpu_to_le16(*(wchar_to + 2));
+				j++;
+				put_unaligned(dst_char, &target[j]);
+			}
+			continue;
+
+unknown:
+			dst_char = cpu_to_le16(0x003f);
+			charlen = 1;
+		}
+
+ctoUTF16:
+		/*
+		 * character may take more than one byte in the source string,
+		 * but will take exactly two bytes in the target string
+		 */
+		i += charlen;
+		put_unaligned(dst_char, &target[j]);
+	}
+
+	return j;
+}