--- a/squashfs-tools/mksquashfs.c
+++ b/squashfs-tools/mksquashfs.c
@@ -117,6 +117,9 @@ unsigned int inode_bytes = 0, inode_size
 char *data_cache = NULL;
 unsigned int cache_bytes = 0, cache_size = 0, inode_count = 0;
 
+/* override all timestamps */
+time_t fixed_time = -1;
+
 /* in memory directory data */
 #define I_COUNT_SIZE		128
 #define DIR_ENTRIES		32
@@ -1554,6 +1557,11 @@ void dir_scan(squashfs_inode *inode, cha
 		perror(buffer);
 		return;
 	}
+
+	/* override timestamp of lstat if fixed_time is given */
+	if(fixed_time != -1)
+		inode_info->buf.st_mtime = fixed_time;
+
 	if(sorted)
 		sort_files_and_write(dir_info);
 	dir_scan2(inode, dir_info);
@@ -1582,6 +1590,10 @@ struct dir_info *dir_scan1(char *pathnam
 			perror(buffer);
 			continue;
 		}
+
+		if(fixed_time != -1)
+			buf.st_mtime = fixed_time;
+
 		if(excluded(filename, &buf))
 			continue;
 
@@ -1621,6 +1633,9 @@ int dir_scan2(squashfs_inode *inode, str
 		char *dir_name = dir_ent->name;
 		unsigned int inode_number = ((buf->st_mode & S_IFMT) == S_IFDIR) ? dir_ent->inode->inode_number : dir_ent->inode->inode_number + dir_inode_no;
 
+		if(fixed_time != -1)
+			buf->st_mtime = fixed_time;
+
 		if(dir_ent->inode->inode == SQUASHFS_INVALID_BLK) {
 			switch(buf->st_mode & S_IFMT) {
 				case S_IFREG:
@@ -1898,6 +1913,16 @@ int main(int argc, char *argv[])
 					exit(1);
 				}
 			}
+		} else if(strcmp(argv[i], "-fixed-time") == 0) {
+			if(++i == argc) {
+				ERROR("%s: -fixed-time missing a timestamp\n", argv[0]);
+				exit(1);
+			}
+			fixed_time = strtoll(argv[i], &b, 10);
+			if(*b != '\0') {
+				ERROR("%s: -fixed-time has an invalid number\n", argv[0]);
+				exit(1);
+			}
 		} else if(strcmp(argv[i], "-noI") == 0 ||
 				strcmp(argv[i], "-noInodeCompression") == 0)
 			noI = TRUE;
@@ -1967,6 +1992,7 @@ printOptions:
 			ERROR("-all-root\t\tmake all files owned by root\n");
 			ERROR("-force-uid uid\t\tset all file uids to uid\n");
 			ERROR("-force-gid gid\t\tset all file gids to gid\n");
+			ERROR("-fixed-time timestamp\tset all timestamps to timestamp\n");
 			ERROR("-le\t\t\tcreate a little endian filesystem\n");
 			ERROR("-be\t\t\tcreate a big endian filesystem\n");
 			ERROR("-nopad\t\t\tdo not pad filesystem to a multiple of 4K\n");
@@ -2190,7 +2216,7 @@ printOptions:
 	sBlk.block_size = block_size;
 	sBlk.block_log = block_log;
 	sBlk.flags = SQUASHFS_MKFLAGS(noI, noD, check_data, noF, no_fragments, always_use_fragments, duplicate_checking);
-	sBlk.mkfs_time = time(NULL);
+	sBlk.mkfs_time = fixed_time != -1 ? fixed_time : time(NULL);
 
 restore_filesystem:
 	write_fragment();