parse_keyword(struct archive_read *a, struct mtree *mtree,
    struct archive_entry *entry, struct mtree_option *opt, int *parsed_kws)
{
	char *val, *key;

	key = opt->value;

	if (*key == '\0')
		return (ARCHIVE_OK);

	if (strcmp(key, "nochange") == 0) {
		*parsed_kws |= MTREE_HAS_NOCHANGE;
		return (ARCHIVE_OK);
	}
	if (strcmp(key, "optional") == 0) {
		*parsed_kws |= MTREE_HAS_OPTIONAL;
		return (ARCHIVE_OK);
	}
	if (strcmp(key, "ignore") == 0) {
		/*
		 * The mtree processing is not recursive, so
		 * recursion will only happen for explicitly listed
		 * entries.
		 */
		return (ARCHIVE_OK);
	}

	val = strchr(key, '=');
	if (val == NULL) {
		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
		    "Malformed attribute \"%s\" (%d)", key, key[0]);
		return (ARCHIVE_WARN);
	}

	*val = '\0';
	++val;

	switch (key[0]) {
	case 'c':
		if (strcmp(key, "content") == 0
		    || strcmp(key, "contents") == 0) {
			parse_escapes(val, NULL);
			archive_strcpy(&mtree->contents_name, val);
			break;
		}
		if (strcmp(key, "cksum") == 0)
			break;
	case 'd':
		if (strcmp(key, "device") == 0) {
			/* stat(2) st_rdev field, e.g. the major/minor IDs
			 * of a char/block special file */
			int r;
			dev_t dev;

			*parsed_kws |= MTREE_HAS_DEVICE;
			r = parse_device(&dev, &a->archive, val);
			if (r == ARCHIVE_OK)
				archive_entry_set_rdev(entry, dev);
			return r;
		}
	case 'f':
		if (strcmp(key, "flags") == 0) {
			*parsed_kws |= MTREE_HAS_FFLAGS;
			archive_entry_copy_fflags_text(entry, val);
			break;
		}
	case 'g':
		if (strcmp(key, "gid") == 0) {
			*parsed_kws |= MTREE_HAS_GID;
			archive_entry_set_gid(entry, mtree_atol10(&val));
			break;
		}
		if (strcmp(key, "gname") == 0) {
			*parsed_kws |= MTREE_HAS_GNAME;
			archive_entry_copy_gname(entry, val);
			break;
		}
	case 'i':
		if (strcmp(key, "inode") == 0) {
			archive_entry_set_ino(entry, mtree_atol10(&val));
			break;
		}
	case 'l':
		if (strcmp(key, "link") == 0) {
			archive_entry_copy_symlink(entry, val);
			break;
		}
	case 'm':
		if (strcmp(key, "md5") == 0 || strcmp(key, "md5digest") == 0)
			break;
		if (strcmp(key, "mode") == 0) {
			if (val[0] >= '0' && val[0] <= '9') {
				*parsed_kws |= MTREE_HAS_PERM;
				archive_entry_set_perm(entry,
				    (mode_t)mtree_atol8(&val));
			} else {
				archive_set_error(&a->archive,
				    ARCHIVE_ERRNO_FILE_FORMAT,
				    "Symbolic mode \"%s\" unsupported", val);
				return ARCHIVE_WARN;
			}
			break;
		}
	case 'n':
		if (strcmp(key, "nlink") == 0) {
			*parsed_kws |= MTREE_HAS_NLINK;
			archive_entry_set_nlink(entry,
				(unsigned int)mtree_atol10(&val));
			break;
		}
	case 'r':
		if (strcmp(key, "resdevice") == 0) {
			/* stat(2) st_dev field, e.g. the device ID where the
			 * inode resides */
			int r;
			dev_t dev;

			r = parse_device(&dev, &a->archive, val);
			if (r == ARCHIVE_OK)
				archive_entry_set_dev(entry, dev);
			return r;
		}
		if (strcmp(key, "rmd160") == 0 ||
		    strcmp(key, "rmd160digest") == 0)
			break;
	case 's':
		if (strcmp(key, "sha1") == 0 || strcmp(key, "sha1digest") == 0)
			break;
		if (strcmp(key, "sha256") == 0 ||
		    strcmp(key, "sha256digest") == 0)
			break;
		if (strcmp(key, "sha384") == 0 ||
		    strcmp(key, "sha384digest") == 0)
			break;
		if (strcmp(key, "sha512") == 0 ||
		    strcmp(key, "sha512digest") == 0)
			break;
		if (strcmp(key, "size") == 0) {
			archive_entry_set_size(entry, mtree_atol10(&val));
			break;
		}
	case 't':
		if (strcmp(key, "tags") == 0) {
			/*
			 * Comma delimited list of tags.
			 * Ignore the tags for now, but the interface
			 * should be extended to allow inclusion/exclusion.
			 */
			break;
		}
		if (strcmp(key, "time") == 0) {
			int64_t m;
			int64_t my_time_t_max = get_time_t_max();
			int64_t my_time_t_min = get_time_t_min();
			long ns = 0;

			*parsed_kws |= MTREE_HAS_MTIME;
			m = mtree_atol10(&val);
			/* Replicate an old mtree bug:
			 * 123456789.1 represents 123456789
			 * seconds and 1 nanosecond. */
			if (*val == '.') {
				++val;
				ns = (long)mtree_atol10(&val);
			} else
				ns = 0;
			if (m > my_time_t_max)
				m = my_time_t_max;
			else if (m < my_time_t_min)
				m = my_time_t_min;
			archive_entry_set_mtime(entry, (time_t)m, ns);
			break;
		}
		if (strcmp(key, "type") == 0) {
			switch (val[0]) {
			case 'b':
				if (strcmp(val, "block") == 0) {
					archive_entry_set_filetype(entry, AE_IFBLK);
					break;
				}
			case 'c':
				if (strcmp(val, "char") == 0) {
					archive_entry_set_filetype(entry,
						AE_IFCHR);
					break;
				}
			case 'd':
				if (strcmp(val, "dir") == 0) {
					archive_entry_set_filetype(entry,
						AE_IFDIR);
					break;
				}
			case 'f':
				if (strcmp(val, "fifo") == 0) {
					archive_entry_set_filetype(entry,
						AE_IFIFO);
					break;
				}
				if (strcmp(val, "file") == 0) {
					archive_entry_set_filetype(entry,
						AE_IFREG);
					break;
				}
			case 'l':
				if (strcmp(val, "link") == 0) {
					archive_entry_set_filetype(entry,
						AE_IFLNK);
					break;
				}
			default:
				archive_set_error(&a->archive,
				    ARCHIVE_ERRNO_FILE_FORMAT,
				    "Unrecognized file type \"%s\"; "
				    "assuming \"file\"", val);
				archive_entry_set_filetype(entry, AE_IFREG);
				return (ARCHIVE_WARN);
			}
			*parsed_kws |= MTREE_HAS_TYPE;
			break;
		}
	case 'u':
		if (strcmp(key, "uid") == 0) {
			*parsed_kws |= MTREE_HAS_UID;
			archive_entry_set_uid(entry, mtree_atol10(&val));
			break;
		}
		if (strcmp(key, "uname") == 0) {
			*parsed_kws |= MTREE_HAS_UNAME;
			archive_entry_copy_uname(entry, val);
			break;
		}
	default:
		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
		    "Unrecognized key %s=%s", key, val);
		return (ARCHIVE_WARN);
	}
	return (ARCHIVE_OK);
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.