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e2c5cc042

Denys Vlasenko

2026-09-21

SUCCESS Duration: 236s

Subject

dpkg: free results of read_package_field(), preliminary cleanups in read_package_field()

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

archival/dpkg.c +45 -35

archival/dpkg.c+45 -35

@@ -531,26 +531,31 @@ static void free_package(common_node_t *node)
	}

	/*
-	* Gets the next package field from package_buffer, separated into the field name
-	* and field value, it returns the int offset to the first character of the next field
+	* Gets the next package field from package_buffer:
+	* "Name:<whitespace>VALUE{\n\|NUL}"
+	* "Name:<whitespace>\n
+	* " VALUE{\n\|NUL}"
+	* separated into "NAME" and "VALUE", both strdup()ed.
+	* Returns the int offset to the first character of the next field.
+	* The package_buffer parameter is NUL-terminated.
	*/
	static int read_package_field(const char package_buffer, char field_name, char *field_value)
	{
	int offset_name_start = 0;
	int offset_name_end = 0;
	int offset_value_start = 0;
-	int offset_value_end = 0;
	int offset = 0;
	int next_offset;
	int name_length;
	int value_length;
	int exit_flag = FALSE;

+	*field_name = NULL;
+	*field_value = NULL;
	if (package_buffer == NULL) {
-	*field_name = NULL;
-	*field_value = NULL;
	return -1;
	}
+
	while (1) {
	next_offset = offset + 1;
	switch (package_buffer[offset]) {
@@ -566,14 +571,14 @@ static int read_package_field(const char package_buffer, char *field_name, cha
	* immediately after name */
	break;
	case '\n':
-	/* TODO: The char next_offset may be out of bounds */
	if (package_buffer[next_offset] != ' ') {
	exit_flag = TRUE;
	break;
	}
+	/* fall through */
	case '\t':
	case ' ':
-	/* increment the value start point if its a just filler */
+	/* increment start points if it is just a filler */
	if (offset_name_start == offset) {
	offset_name_start++;
	}
@@ -584,9 +589,8 @@ static int read_package_field(const char package_buffer, char *field_name, cha
	}
	if (exit_flag) {
	/* Check that the names are valid */
-	offset_value_end = offset;
	name_length = offset_name_end - offset_name_start;
-	value_length = offset_value_end - offset_value_start;
+	value_length = offset - offset_value_start;
	if (name_length == 0) {
	break;
	}
@@ -594,27 +598,26 @@ static int read_package_field(const char package_buffer, char *field_name, cha
	break;
	}

-	/* If not valid, start fresh with next field */
+	/* Not valid: start fresh with next field */
	exit_flag = FALSE;
	offset_name_start = offset + 1;
	offset_name_end = 0;
	offset_value_start = offset + 1;
-	offset_value_end = offset + 1;
	offset++;
	}
	offset++;
-	}
-	*field_name = NULL;
-	if (name_length) {
+	} /* while (1) */
+
+	if (name_length > 0) {
	*field_name = xstrndup(&package_buffer[offset_name_start], name_length);
	}
-	*field_value = NULL;
	if (value_length > 0) {
	*field_value = xstrndup(&package_buffer[offset_value_start], value_length);
	}
	return next_offset;
	}

+	/* The parameter is NUL-terminated */
	static unsigned fill_package_struct(char *control_buffer)
	{
	static const char field_names[] ALIGN1 =
@@ -623,14 +626,14 @@ static unsigned fill_package_struct(char *control_buffer)
	"Conflicts\0""Suggests\0""Recommends\0""Enhances\0";

	common_node_t *new_node = xzalloc(sizeof(common_node_t));
-	char *field_name;
-	char *field_value;
	int field_start = 0;
-	int num = -1;
	int buffer_length = strlen(control_buffer);
+	int num;

	new_node->version = search_name_hashtable("unknown");
	while (field_start < buffer_length) {
+	char *field_name;
+	char *field_value;
	unsigned field_num;

	field_start += read_package_field(&control_buffer[field_start],
@@ -799,7 +802,7 @@ static void write_buffer_no_status(FILE new_status_file, const char control_bu
	char *name;
	char *value;
	int start = 0;
-	while (1) {
+	while (control_buffer[start]) {
	start += read_package_field(&control_buffer[start], &name, &value);
	if (name == NULL) {
	break;
@@ -807,6 +810,8 @@ static void write_buffer_no_status(FILE new_status_file, const char control_bu
	if (strcmp(name, "Status") != 0) {
	fprintf(new_status_file, "%s: %s\n", name, value);
	}
+	free(name);
+	free(value);
	}
	}

@@ -815,34 +820,35 @@ static void write_status_file(deb_file_t **deb_file)
	{
	FILE *old_status_file = xfopen_for_read("/var/lib/dpkg/status");
	FILE *new_status_file = xfopen_for_write("/var/lib/dpkg/status.udeb");
-	char *package_name;
-	char *status_from_file;
-	char *control_buffer = NULL;
-	char *tmp_string;
-	int status_num;
+	char *control_buffer;
	int field_start = 0;
-	int write_flag;
-	int i = 0;
+	int status_num;
+	int i;

	/* Update previously known packages */
	while ((control_buffer = xmalloc_fgetline_str(old_status_file, "\n\n")) != NULL) {
+	char *package_name;
+	char *status_from_file;
+	char *tmp_string;
+	int write_flag;
+	//FIXME: "int field_start = 0;" should be _here_, right?
+
	tmp_string = strstr(control_buffer, "Package:");
	if (tmp_string == NULL) {
+	free(control_buffer);
	continue;
	}
-
	tmp_string += 8;
	tmp_string += strspn(tmp_string, " \n\t");
	package_name = xstrndup(tmp_string, strcspn(tmp_string, "\n"));
+
	write_flag = FALSE;
+	status_from_file = NULL;
	tmp_string = strstr(control_buffer, "Status:");
	if (tmp_string != NULL) {
-	/* Separate the status value from the control buffer */
	tmp_string += 7;
	tmp_string += strspn(tmp_string, " \n\t");
	status_from_file = xstrndup(tmp_string, strcspn(tmp_string, "\n"));
-	} else {
-	status_from_file = NULL;
	}

	/* Find this package in the status hashtable */
@@ -870,7 +876,7 @@ static void write_status_file(deb_file_t **deb_file)
	}
	i++;
	}
-	/* This is temperary, debugging only */
+	/* This is temporary, debugging only */
	if (deb_file[i] == NULL) {
	bb_error_msg_and_die("ALERT: cannot find a control file, "
	"your status file may be broken, status may be "
@@ -882,7 +888,7 @@ static void write_status_file(deb_file_t **deb_file)
	fprintf(new_status_file, "Package: %s\n", package_name);
	fprintf(new_status_file, "Status: %s\n", status_from_hashtable);

-	while (1) {
+	while (control_buffer[field_start]) {
	char *field_name;
	char *field_value;
	field_start += read_package_field(&control_buffer[field_start], &field_name, &field_value);
@@ -894,13 +900,15 @@ static void write_status_file(deb_file_t **deb_file)
	) {
	fprintf(new_status_file, "%s: %s\n", field_name, field_value);
	}
+	free(field_name);
+	free(field_value);
	}
	write_flag = TRUE;
	fputs("\n", new_status_file);
	}
	else if (strcmp("config-files", name_hashtable[state_status]) == 0) {
	/* only change the status line */
-	while (1) {
+	while (control_buffer[field_start]) {
	char *field_name;
	char *field_value;
	field_start += read_package_field(&control_buffer[field_start], &field_name, &field_value);
@@ -913,13 +921,15 @@ static void write_status_file(deb_file_t **deb_file)
	} else {
	fprintf(new_status_file, "%s: %s\n", field_name, field_value);
	}
+	free(field_name);
+	free(field_value);
	}
	write_flag = TRUE;
	fputs("\n", new_status_file);
	}
	}
	}
-	/* If the package from the status file wasn't handle above, do it now*/
+	/* If the package from the status file wasn't handled above, do it now */
	if (!write_flag) {
	fprintf(new_status_file, "%s\n\n", control_buffer);
	}
@@ -927,7 +937,7 @@ static void write_status_file(deb_file_t **deb_file)
	free(status_from_file);
	free(package_name);
	free(control_buffer);
-	}
+	} /* while (control_buffer) */

	/* Write any new packages */
	for (i = 0; deb_file[i] != NULL; i++) {