Public bug reported: I tested an UDF iso image with mount -o loop... and I was really surprised, the mount changed the image. I am not sure what it writes to the image, probably almost nothing (mount time stamp?) but the checksum of the image is changed. It's very bad when you download something you mount it (just to test) and then you want to check the checksum of the file....
to check: $ mkdir testdir $ genisoimage -udf -o testimage.iso testdir/ ... $ sudo md5sum testimage.iso 92c720ac623ed697e222047b23935a0c testimage.iso $ sudo mount -o loop testimage.iso /mnt mount: block device /home/qji/testimage.iso is write-protected, mounting read-only < --- mount says it's a read only mount $ md5sum testimage.iso 0bc99bab37df097c5aabff7bc6a6de68 testimage.iso < --- checksum is already changed $ sudo umount /mnt $ md5sum testimage.iso 0bc99bab37df097c5aabff7bc6a6de68 testimage.iso < --- umount doesn't touch the file ** Affects: kernel-package (Ubuntu) Importance: Undecided Status: New ** Tags: mount udf -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1277146 Title: mount -o loop.... changes the udf image To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kernel-package/+bug/1277146/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs