[Qemu-commits] [qemu/qemu] 4837a1: xen/blkif: avoid double access to any shared ring ...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/qemu/qemu
  Commit: 4837a1a51638ef1719bf8149591a57e7207db41a
      
https://github.com/qemu/qemu/commit/4837a1a51638ef1719bf8149591a57e7207db41a
  Author: Jan Beulich <address@hidden>
  Date:   2016-06-13 (Mon, 13 Jun 2016)

  Changed paths:
    M hw/block/xen_blkif.h
    M hw/block/xen_disk.c

  Log Message:
  -----------
  xen/blkif: avoid double access to any shared ring request fields

Commit f9e98e5d7a ("xen/blkif: Avoid double access to
src->nr_segments") didn't go far enough: src->operation is also being
used twice. And nothing was done to prevent the compiler from using the
source side of the copy done by blk_get_request() (granted that's very
unlikely).

Move the barrier()s up, and add another one to blk_get_request().

Note that for completing XSA-155, the barrier() getting added to
blk_get_request() would suffice, and hence the changes to xen_blkif.h
are more like just cleanup. And since, as said, the unpatched code
getting compiled to something vulnerable is very unlikely (and not
observed in practice), this isn't being viewed as a new security issue.

Signed-off-by: Jan Beulich <address@hidden>
Reviewed-by: Stefano Stabellini <address@hidden>
Signed-off-by: Stefano Stabellini <address@hidden>


  Commit: b1b23e5bbfb66d9401e2c2b0646fb721d94a3f83
      
https://github.com/qemu/qemu/commit/b1b23e5bbfb66d9401e2c2b0646fb721d94a3f83
  Author: Peter Maydell <address@hidden>
  Date:   2016-06-14 (Tue, 14 Jun 2016)

  Changed paths:
    M hw/usb/xen-usb.c
    M include/hw/xen/xen.h

  Log Message:
  -----------
  xen: Clean up includes

Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

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


  Commit: 49237b856ae58ee7955be0b959c504c51b014f20
      
https://github.com/qemu/qemu/commit/49237b856ae58ee7955be0b959c504c51b014f20
  Author: Peter Maydell <address@hidden>
  Date:   2016-06-14 (Tue, 14 Jun 2016)

  Changed paths:
    M hw/block/xen_blkif.h
    M hw/block/xen_disk.c
    M hw/usb/xen-usb.c
    M include/hw/xen/xen.h

  Log Message:
  -----------
  Merge remote-tracking branch 'remotes/sstabellini/tags/xen-20160614-tag' into 
staging

Xen 2016/06/14

# gpg: Signature made Tue 14 Jun 2016 16:01:52 BST
# gpg:                using RSA key 0x894F8F4870E1AE90
# gpg: Good signature from "Stefano Stabellini <address@hidden>"
# Primary key fingerprint: D04E 33AB A51F 67BA 07D3  0AEA 894F 8F48 70E1 AE90

* remotes/sstabellini/tags/xen-20160614-tag:
  xen: Clean up includes
  xen/blkif: avoid double access to any shared ring request fields

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


Compare: https://github.com/qemu/qemu/compare/1be08a0946b1...49237b856ae5