[Qemu-commits] [qemu/qemu] 93e32b: qcow2: Fix preallocation bdrv_pwrite to wrong file

[Peter Maydell]

  Branch: refs/heads/master
  Home:   https://github.com/qemu/qemu
  Commit: 93e32b3e2012a668e4da1c2566d2935c24060435
      
https://github.com/qemu/qemu/commit/93e32b3e2012a668e4da1c2566d2935c24060435
  Author: Kevin Wolf <address@hidden>
  Date:   2019-04-16 (Tue, 16 Apr 2019)

  Changed paths:
    M block/qcow2.c

  Log Message:
  -----------
  qcow2: Fix preallocation bdrv_pwrite to wrong file

With an external data file, preallocate_co() must write the final byte
to the external data file, not to the qcow2 image file.

This is harmless for preallocation of newly created images (only the
qcow2 file size is increased to the virtual disk size while it should be
much smaller), but with preallocated resize, it could in theory cause
visible corruption if the metadata of the image is larger than the data
(e.g. lots of bitmaps).

Signed-off-by: Kevin Wolf <address@hidden>
Reviewed-by: Eric Blake <address@hidden>


  Commit: dbfc49b69afc616227769f4ab928e452ac7af061
      
https://github.com/qemu/qemu/commit/dbfc49b69afc616227769f4ab928e452ac7af061
  Author: Peter Maydell <address@hidden>
  Date:   2019-04-16 (Tue, 16 Apr 2019)

  Changed paths:
    M block/qcow2.c

  Log Message:
  -----------
  Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- qcow2: Fix potential corruption for preallocated resize with external data 
file

# gpg: Signature made Tue 16 Apr 2019 15:23:35 BST
# gpg:                using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <address@hidden>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream:
  qcow2: Fix preallocation bdrv_pwrite to wrong file

Signed-off-by: Peter Maydell <address@hidden>


Compare: https://github.com/qemu/qemu/compare/a9b305ba291f...dbfc49b69afc