Hi, This issue has been fixed in master (5f77ef69a195098baddfdc6d189f1b4a94587378):
$ ./qemu-io copy.img -c 'write 2856960 208896' qcow2_free_clusters failed: Invalid argument qcow2_free_clusters failed: Invalid argument qcow2_free_clusters failed: Invalid argument qcow2_free_clusters failed: Invalid argument qcow2_free_clusters failed: Invalid argument qcow2_free_clusters failed: File too large qcow2_free_clusters failed: Invalid argument qcow2: Image is corrupt: Cannot free unaligned cluster 0xfffffffffffe00; further non-fatal corruption events will be suppressed qcow2_free_clusters failed: Invalid argument qcow2: Marking image as corrupt: Data cluster offset 0xfffffe00 unaligned (guest offset: 0x2e1000); further corruption events will be suppressed write failed: Input/output error Thanks for your report (and your fuzzer), Max -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1354529 Title: qemu-io: Assert failure on the fuzzed qcow2 image Status in QEMU: Fix Committed Bug description: 'qemu-io -c write' failed on the fuzzed image with missed refcount tables: Sequence: 1. Unpack the attached archive, make a copy of test.img 2. Put copy.img and backing_img.cow in the same directory 3. Execute qemu-io copy.img -c 'write 2856960 208896' Result: qemu-io was killed by SIGIOT with the reason: qemu-io: block/qcow2-cluster.c:910: handle_copied: Assertion `*host_offset == 0 || offset_into_cluster(s, guest_offset) == offset_into_cluster(s, *host_offset)' failed. qemu.git HEAD 2d591ce2aeebf To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1354529/+subscriptions
