tools: acrn-crashlog: fix potential issues under common and usercrash

This patch is to fix buffer overflow, return value not unified and
variable type not matched issues. And add some judge logic to improve
code quality.

Changes:
1. Handle the fd properly in the failing case.
2. Fix buffer overflow issues and null pointer access issues.
3. Fix the format issue in log_sys.c.
4. Remove the useless branch and adjust the function logic.
5. Add some checks for the string length before using strcpy/strcat/memcpy.
6. Fix strncpy null-terminated issues.
7. Change the return value to unify the return type.

Signed-off-by: CHEN Gang <gang.c.chen@intel.com>
Signed-off-by: xiaojin2 <xiaojing.liu@intel.com>
Reviewed-by: Zhi Jin <zhi.jin@intel.com>
Reviewed-by: Liu Xinwu <xinwu.liu@intel.com>
Acked-by: Zhang Di <di.zhang@intel.com>

tools/acrn-crashlog/common/cmdutils.c

@@ -47,7 +47,7 @@ int execv_out2file(char *argv[], char *outfile)
 
 	if (pid == 0) {
 		int res;
-		int fd;
+		int fd = -1;
 
 		if (outfile) {
 			fd = open(outfile, O_WRONLY | O_CREAT | O_TRUNC, 0664);
@@ -65,6 +65,8 @@ int execv_out2file(char *argv[], char *outfile)
 
 		res = execvp(argv[0], argv);
 		if (res == -1) {
+			if (fd > 0)
+				close(fd);
 			LOGE("execvp (%s) failed, error (%s)\n", argv[0],
 			     strerror(errno));
 			return -1;
@@ -211,8 +213,10 @@ char *exec_out2mem(char *fmt, ...)
 			memsize += 1024;
 			new = realloc(out, memsize);
 			if (!new) {
-				if (out)
+				if (out) {
 					free(out);
+					out = NULL;
+				}
 				goto end;
 			} else {
 				out = new;

tools/acrn-crashlog/common/fsutils.c

@@ -114,11 +114,12 @@ char *mm_get_line(struct mm_file_t *mfile, int line)
 
 	if (line <= 0 || line > mm_count_lines(mfile))
 		return NULL;
-	else if (line == 1)
+
+	if (line == 1)
 		ret = begin;
 	else {
 		next = begin;
-		for (i = 2; i <= line; i++)
+		for (i = 2; i <= line && next; i++)
 			next = strchr(next, '\n') + 1;
 		ret = next;
 	}
@@ -820,7 +821,7 @@ int read_full_binary_file(const char *path, unsigned long *size, void **data)
 	close_file(path, f);
 
 	*data = buf;
-	*size = (unsigned int)_size;
+	*size = (unsigned long)_size;
 
 	return 0;
 
@@ -1112,7 +1113,7 @@ int read_file(const char *path, unsigned long *size, void **data)
 	int len = 0;
 	int fd = 0;
 	int memsize = 1; /* for '\0' */
-	size_t result = 0;
+	ssize_t result = 0;
 	char *out = NULL;
 	char *new;
 
@@ -1129,6 +1130,8 @@ int read_file(const char *path, unsigned long *size, void **data)
 		result = read(fd, (void *)tmp, 1024);
 		if (result == 0)
 			break;
+		else if (result == -1)
+			goto free;
 
 		memsize += result;
 		new = realloc(out, memsize);
@@ -1145,7 +1148,7 @@ int read_file(const char *path, unsigned long *size, void **data)
 	close(fd);
 
 	*data = out;
-	*size = (unsigned int)len;
+	*size = (unsigned long)len;
 
 	return 0;
 

tools/acrn-crashlog/common/log_sys.c

@@ -19,7 +19,7 @@ void do_log(const int level,
 	char log[MAX_LOG_LEN];
 	int n = 0;
 #ifdef DEBUG_ACRN_CRASHLOG
-	const char header_fmt[] = "<%-20s%d>: ";
+	const char header_fmt[] = "<%-20s%5d>: ";
 #endif
 
 	if (level > LOG_LEVEL)
@@ -37,7 +37,7 @@ void do_log(const int level,
 #ifdef DEBUG_ACRN_CRASHLOG
 	/* header */
 	n = snprintf(log, sizeof(log), header_fmt, func, line);
-	if (n < 0 || n >= sizeof(log))
+	if (n < 0 || (size_t)n >= sizeof(log))
 		n = 0;
 #endif
 	/* msg */

tools/acrn-crashlog/common/strutils.c

@@ -74,11 +74,16 @@ static char *strtriml(char *str)
 
 static char *strtrimr(char *str)
 {
-	char *end = str + strlen(str) - 1;
+	size_t len;
+	char *end;
 
-	while (*end == ' ' && end >= str) {
-		*end = 0;
-		end--;
+	len = strlen(str);
+	if (len > 0) {
+		end = str + strlen(str) - 1;
+		while (*end == ' ' && end >= str) {
+			*end = 0;
+			end--;
+		}
 	}
 
 	return str;
@@ -86,8 +91,12 @@ static char *strtrimr(char *str)
 
 char *strtrim(char *str)
 {
-	strtrimr(str);
-	return strtriml(str);
+	if (str) {
+		strtrimr(str);
+		return strtriml(str);
+	}
+
+	return NULL;
 }
 
 int strcnt(char *str, char c)