1 files changed, 28 insertions, 38 deletions

diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 2aeaf9765b..6a77f1c779 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -206,7 +206,7 @@ char kdb_getchar(void)
  */
 static void kdb_position_cursor(char *prompt, char *buffer, char *cp)
 {
-	kdb_printf("\r%s", kdb_prompt_str);
+	kdb_printf("\r%s", prompt);
 	if (cp > buffer)
 		kdb_printf("%.*s", (int)(cp - buffer), buffer);
 }
@@ -239,6 +239,7 @@ static char *kdb_read(char *buffer, size_t bufsize)
 						 * and null byte */
 	char *lastchar;
 	char *p_tmp;
+	char tmp;
 	static char tmpbuffer[CMD_BUFLEN];
 	int len = strlen(buffer);
 	int len_tmp;
@@ -246,8 +247,7 @@ static char *kdb_read(char *buffer, size_t bufsize)
 	int count;
 	int i;
 	int diag, dtab_count;
-	int key, buf_size, ret;
-
+	int key, ret;
 
 	diag = kdbgetintenv("DTABCOUNT", &dtab_count);
 	if (diag)
@@ -269,12 +269,9 @@ poll_again:
 	switch (key) {
 	case 8: /* backspace */
 		if (cp > buffer) {
-			if (cp < lastchar) {
-				memcpy(tmpbuffer, cp, lastchar - cp);
-				memcpy(cp-1, tmpbuffer, lastchar - cp);
-			}
-			*(--lastchar) = '\0';
-			--cp;
+			memmove(cp-1, cp, lastchar - cp + 1);
+			lastchar--;
+			cp--;
 			kdb_printf("\b%s ", cp);
 			kdb_position_cursor(kdb_prompt_str, buffer, cp);
 		}
@@ -291,9 +288,8 @@ poll_again:
 		return buffer;
 	case 4: /* Del */
 		if (cp < lastchar) {
-			memcpy(tmpbuffer, cp+1, lastchar - cp - 1);
-			memcpy(cp, tmpbuffer, lastchar - cp - 1);
-			*(--lastchar) = '\0';
+			memmove(cp, cp+1, lastchar - cp);
+			lastchar--;
 			kdb_printf("%s ", cp);
 			kdb_position_cursor(kdb_prompt_str, buffer, cp);
 		}
@@ -333,21 +329,16 @@ poll_again:
 	case 9: /* Tab */
 		if (tab < 2)
 			++tab;
-		p_tmp = buffer;
-		while (*p_tmp == ' ')
-			p_tmp++;
-		if (p_tmp > cp)
-			break;
-		memcpy(tmpbuffer, p_tmp, cp-p_tmp);
-		*(tmpbuffer + (cp-p_tmp)) = '\0';
-		p_tmp = strrchr(tmpbuffer, ' ');
-		if (p_tmp)
-			++p_tmp;
-		else
-			p_tmp = tmpbuffer;
-		len = strlen(p_tmp);
-		buf_size = sizeof(tmpbuffer) - (p_tmp - tmpbuffer);
-		count = kallsyms_symbol_complete(p_tmp, buf_size);
+
+		tmp = *cp;
+		*cp = '\0';
+		p_tmp = strrchr(buffer, ' ');
+		p_tmp = (p_tmp ? p_tmp + 1 : buffer);
+		strscpy(tmpbuffer, p_tmp, sizeof(tmpbuffer));
+		*cp = tmp;
+
+		len = strlen(tmpbuffer);
+		count = kallsyms_symbol_complete(tmpbuffer, sizeof(tmpbuffer));
 		if (tab == 2 && count > 0) {
 			kdb_printf("\n%d symbols are found.", count);
 			if (count > dtab_count) {
@@ -359,32 +350,32 @@ poll_again:
 			}
 			kdb_printf("\n");
 			for (i = 0; i < count; i++) {
-				ret = kallsyms_symbol_next(p_tmp, i, buf_size);
+				ret = kallsyms_symbol_next(tmpbuffer, i, sizeof(tmpbuffer));
 				if (WARN_ON(!ret))
 					break;
 				if (ret != -E2BIG)
-					kdb_printf("%s ", p_tmp);
+					kdb_printf("%s ", tmpbuffer);
 				else
-					kdb_printf("%s... ", p_tmp);
-				*(p_tmp + len) = '\0';
+					kdb_printf("%s... ", tmpbuffer);
+				tmpbuffer[len] = '\0';
 			}
 			if (i >= dtab_count)
 				kdb_printf("...");
 			kdb_printf("\n");
-			kdb_printf(kdb_prompt_str);
+			kdb_printf("%s",  kdb_prompt_str);
 			kdb_printf("%s", buffer);
 			if (cp != lastchar)
 				kdb_position_cursor(kdb_prompt_str, buffer, cp);
 		} else if (tab != 2 && count > 0) {
 			/* How many new characters do we want from tmpbuffer? */
-			len_tmp = strlen(p_tmp) - len;
+			len_tmp = strlen(tmpbuffer) - len;
 			if (lastchar + len_tmp >= bufend)
 				len_tmp = bufend - lastchar;
 
 			if (len_tmp) {
 				/* + 1 ensures the '\0' is memmove'd */
 				memmove(cp+len_tmp, cp, (lastchar-cp) + 1);
-				memcpy(cp, p_tmp+len, len_tmp);
+				memcpy(cp, tmpbuffer+len, len_tmp);
 				kdb_printf("%s", cp);
 				cp += len_tmp;
 				lastchar += len_tmp;
@@ -398,9 +389,8 @@ poll_again:
 	default:
 		if (key >= 32 && lastchar < bufend) {
 			if (cp < lastchar) {
-				memcpy(tmpbuffer, cp, lastchar - cp);
-				memcpy(cp+1, tmpbuffer, lastchar - cp);
-				*++lastchar = '\0';
+				memmove(cp+1, cp, lastchar - cp + 1);
+				lastchar++;
 				*cp = key;
 				kdb_printf("%s", cp);
 				++cp;
@@ -463,7 +453,7 @@ char *kdb_getstr(char *buffer, size_t bufsize, const char *prompt)
 {
 	if (prompt && kdb_prompt_str != prompt)
 		strscpy(kdb_prompt_str, prompt, CMD_BUFLEN);
-	kdb_printf(kdb_prompt_str);
+	kdb_printf("%s", kdb_prompt_str);
 	kdb_nextline = 1;	/* Prompt and input resets line number */
 	return kdb_read(buffer, bufsize);
 }