The following pattern is unsafe:

  char buf[32];
  ret = read(fd, buf, sizeof(buf));
  ...
  buf[ret] = 0;

If read(2) returns 32 then a byte beyond the end of the buffer is
zeroed.

In practice this buffer overflow does not occur because the sysfs
max_segments file only contains an unsigned short + '\n'.  The string is
always shorter than 32 bytes.

Regardless, avoid this pattern because static analysis tools might
complain and it could lead to real buffer overflows if copy-pasted
elsewhere in the codebase.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

cirrus: blitter fixes.

# gpg: Signature made Thu 16 Mar 2017 09:05:22 GMT
# gpg:                using RSA key 0x4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/pull-cirrus-20170316-1:
  cirrus: stop passing around src pointers in the blitter
  cirrus: stop passing around dst pointers in the blitter
  cirrus: fix cirrus_invalidate_region
  cirrus: add option to disable blitter
  cirrus: switch to 4 MB video memory by default
  cirrus/vnc: zap bitblit support from console code.
  fix :cirrus_vga fix OOB read case qemu Segmentation fault

# Conflicts:
#	include/hw/compat.h
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

migration/next for 20170316

# gpg: Signature made Thu 16 Mar 2017 08:21:51 GMT
# gpg:                using RSA key 0xF487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* remotes/juanquintela/tags/migration/20170316:
  postcopy: Check for shared memory
  RAMBlocks: qemu_ram_is_shared
  vmstate: fix failed iotests case 68 and 91
  migration/block: Avoid invoking blk_drain too frequently
  migration: use "" as the default for tls-creds/hostname
  Change the method to calculate dirty-pages-rate
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Pull request

Tracing makefile fixes for QEMU 2.9.

# gpg: Signature made Thu 16 Mar 2017 06:56:10 GMT
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  trace: ensure $(tracetool-y) is defined in top level makefile
  makefile: generate trace-events-all upfront
  makefile: merge GENERATED_HEADERS & GENERATED_SOURCES variables
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Commit c2cabb34 inadvertently downgraded the 'dtc' submodule,
undoing the increments added in earlier commits. Revert this,
returning the submodule state to where we should be.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

QAPI patches for 2017-03-16

# gpg: Signature made Thu 16 Mar 2017 06:18:38 GMT
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2017-03-16: (49 commits)
  qapi: Fix a misleading parser error message
  qapi: Make pylint a bit happier
  qapi: Drop unused .check_clash() parameter schema
  qapi: union_types is a list used like a dict, make it one
  qapi: struct_types is a list used like a dict, make it one
  qapi: enum_types is a list used like a dict, make it one
  qapi: Factor add_name() calls out of the meta conditional
  qapi: Simplify what gets stored in enum_types
  qapi: Drop unused variable events
  qapi: Eliminate check_docs() and drop QAPIDoc.expr
  qapi: Fix detection of bogus member documentation
  tests/qapi-schema: Improve coverage of bogus member docs
  tests/qapi-schema: Rename doc-bad-args to doc-bad-command-arg
  qapi: Move empty doc section checking to doc parser
  qapi: Improve error message on @NAME: in free-form doc
  qapi: Move detection of doc / expression name mismatch
  qapi: Fix detection of doc / expression mismatch
  tests/qapi-schema: Improve doc / expression mismatch coverage
  qapi2texi: Use category "Object" for all object types
  qapi2texi: Generate descriptions for simple union tags
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

virtio, pci: fixes

More fixes missed in the previous pull request.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Thu 16 Mar 2017 02:29:49 GMT
# gpg:                using RSA key 0x281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
  virtio-serial-bus: Delete timer from list before free it
  hw/virtio: fix Power Management Control Register for PCI Express virtio devices
  hw/virtio: fix Link Control Register for PCI Express virtio devices
  hw/virtio: fix error enabling flags in Device Control register
  hw/pcie: fix Extended Configuration Space for devices with no Extended Capabilities
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Thu 16 Mar 2017 00:52:41 GMT
# gpg:                using RSA key 0x7DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>"
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/ide-pull-request:
  ide: ahci: call cleanup function in ahci unit
  ide: core: add cleanup function
  ide: qdev: register ide bus unrealize function
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Postcopy doesn't support migration of RAM shared with another process
yet (we've got a bunch of things to understand).
Check for the case and don't allow postcopy to be enabled.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Provide a helper to say whether a RAMBlock was created as a
shared mapping.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

This problem affects s390x only if we are running without KVM.
Basically, S390CPU.irqstate is unused if we do not use KVM,
and thus no buffer is allocated.
This causes size=0, first_elem=NULL and n_elems=1 in
vmstate_load_state and vmstate_save_state. And the assert fails.
With this fix we can go back to the old behavior and support
VMS_VBUFFER with size 0 and nullptr.
Signed-off-by: NQingFeng Hao <haoqf@linux.vnet.ibm.com>
Signed-off-by: NHalil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Increase bmds->cur_dirty after submit io, so reduce the frequency
involve into blk_drain, and improve the performance obviously
when block migration.

The performance test result of this patch:

During the block dirty save phase, this patch improve guest os IOPS
from 4.0K to 9.5K. and improve the migration speed from
505856 rsec/s to 855756 rsec/s.
Signed-off-by: NLidong Chen <jemmy858585@gmail.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Does basically the same as "cirrus: stop passing around dst pointers in
the blitter", just for the src pointer instead of the dst pointer.

For the src we have to care about cputovideo blits though and fetch the
data from s->cirrus_bltbuf instead of vga memory.  The cirrus_src*()
helper functions handle that.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489584487-3489-1-git-send-email-kraxel@redhat.com

Instead pass around the address (aka offset into vga memory).  Calculate
the pointer in the rop_* functions, after applying the mask to the
address, to make sure the address stays within the valid range.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489574872-8679-1-git-send-email-kraxel@redhat.com

off_cur_end is exclusive, so off_cur_end == cirrus_addr_mask is valid.
Fix calculation to make sure to allow that, otherwise the assert added
by commit f153b563 can trigger for valid
blits.

Test case: boot windows nt 4.0
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489579606-26020-1-git-send-email-kraxel@redhat.com

Ok, we have this beast in the cirrus code which is not used at all by
modern guests, except when you try to find security holes in qemu.  So,
add an option to disable blitter altogether.  Guests released within
the last ten years should not show any rendering issues if you turn off
blitter support.

There are no known bugs in the cirrus blitter code.  But in the past we
hoped a few times already that we've finally nailed the last issue.  So
having some easy way to mitigate in case yet another blitter issue shows
up certainly makes me sleep a bit better at night.

For completeness:  The by far better way to mitigate is to switch away
from cirrus and use stdvga instead.  Or something more modern like
virtio-vga in case your guest has support for it.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489494540-15745-1-git-send-email-kraxel@redhat.com

Quoting cirrus source code:
   Follow real hardware, cirrus card emulated has 4 MB video memory.
   Also accept 8 MB/16 MB for backward compatibility.

So just use 4MB by default.  We decided to leave that at 8MB by default
a while ago, for live migration compatibility reasons.  But we have
compat properties to handle that, so that isn't a compeling reason.

This also removes some sanity check inconsistencies in the cirrus code.
Some places check against the allocated video memory, some places check
against the 4MB physical hardware has.  Guest code can trigger asserts
because of that.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489494514-15606-1-git-send-email-kraxel@redhat.com

There is a special code path (dpy_gfx_copy) to allow graphic emulation
notify user interface code about bitblit operations carryed out by
guests.  It is supported by cirrus and vnc server.  The intended purpose
is to optimize display scrolls and just send over the scroll op instead
of a full display update.

This is rarely used these days though because modern guests simply don't
use the cirrus blitter any more.  Any linux guest using the cirrus drm
driver doesn't.  Any windows guest newer than winxp doesn't ship with a
cirrus driver any more and thus uses the cirrus as simple framebuffer.

So this code tends to bitrot and bugs can go unnoticed for a long time.
See for example commit "3e10c3ec vnc: fix qemu crash because of SIGSEGV"
which fixes a bug lingering in the code for almost a year, added by
commit "c7628bff vnc: only alloc server surface with clients connected".

Also the vnc server will throttle the frame rate in case it figures the
network can't keep up (send buffers are full).  This doesn't work with
dpy_gfx_copy, for any copy operation sent to the vnc client we have to
send all outstanding updates beforehand, otherwise the vnc client might
run the client side blit on outdated data and thereby corrupt the
display.  So this dpy_gfx_copy "optimization" might even make things
worse on slow network links.

Lets kill it once for all.

Oh, and one more reason: Turns out (after writing the patch) we have a
security bug in that code path ...

Fixes: CVE-2016-9603
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489494419-14340-1-git-send-email-kraxel@redhat.com

check the validity of parameters in cirrus_bitblt_rop_fwd_transp_xxx
and cirrus_bitblt_rop_fwd_xxx to avoid the OOB read which causes qemu Segmentation fault.

After the fix, we will touch the assert in
cirrus_invalidate_region:
assert(off_cur_end >= off_cur);
Signed-off-by: Nfangying <fangying1@huawei.com>
Signed-off-by: Nhangaohuai <hangaohuai@huawei.com>
Message-id: 20170314063919.16200-1-hangaohuai@huawei.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

The tls-creds parameter has a default value of NULL indicating
that TLS should not be used. Setting it to non-NULL enables
use of TLS. Once tls-creds are set to a non-NULL value via the
monitor, it isn't possible to set them back to NULL again, due
to current implementation limitations. The empty string is not
a valid QObject identifier, so this switches to use "" as the
default, indicating that TLS will not be used

The tls-hostname parameter has a default value of NULL indicating
the the hostname from the migrate connection URI should be used.
Again, once tls-hostname is set non-NULL, to override the default
hostname for x509 cert validation, it isn't possible to reset it
back to NULL via the monitor. The empty string is not a valid
hostname, so this switches to use "" as the default, indicating
that the migrate URI hostname should be used.

Using "" as the default for both, also means that the monitor
commands "info migrate_parameters" / "query-migrate-parameters"
will report existance of tls-creds/tls-parameters even when set
to their default values.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

In function cpu_physical_memory_sync_dirty_bitmap, file
include/exec/ram_addr.h:

if (src[idx][offset]) {
    unsigned long bits = atomic_xchg(&src[idx][offset], 0);
    unsigned long new_dirty;
    new_dirty = ~dest[k];
    dest[k] |= bits;
    new_dirty &= bits;
    num_dirty += ctpopl(new_dirty);
}

After these codes executed, only the pages not dirtied in bitmap(dest),
but dirtied in dirty_memory[DIRTY_MEMORY_MIGRATION] will be calculated.
For example:
When ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] = 0b00001111,
and atomic_rcu_read(&migration_bitmap_rcu)->bmap = 0b00000011,
the new_dirty will be 0b00001100, and this function will return 2 but not
4 which is expected.
the dirty pages in dirty_memory[DIRTY_MEMORY_MIGRATION] are all new,
so these should be calculated also.
Signed-off-by: NChao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Update OpenBIOS images

# gpg: Signature made Wed 15 Mar 2017 21:01:53 GMT
# gpg:                using RSA key 0x5BC2C56FAE0F321F
# gpg: Good signature from "Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>"
# Primary key fingerprint: CC62 1AB9 8E82 200D 915C  C9C4 5BC2 C56F AE0F 321F

* remotes/mcayland/tags/qemu-openbios-signed:
  Update OpenBIOS images to f233c3f built from submodule.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

When choking on a token where an expression is expected, we report
'Expected "{", "[" or string'.  Close, but no cigar.  Fix it to
Expected '"{", "[", string, boolean or "null"'.

Missed in commit e53188ad.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-48-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-47-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-46-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-45-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-44-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-43-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-42-git-send-email-armbru@redhat.com>

Don't invent a new dictionary structure just for enum_types, simply
store the defining expression, like we do for struct_types and
union_types.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-41-git-send-email-armbru@redhat.com>

Missed in commit e98859a9Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-40-git-send-email-armbru@redhat.com>

Move what's left in check_docs() to check_expr().  Delegate the actual
checking to new QAPIDoc.check_expr().

QAPIDoc.expr is now unused; drop it.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-39-git-send-email-armbru@redhat.com>

check_definition_doc() checks for member documentation without a
matching member.  It laboriously second-guesses what members
QAPISchema._def_exprs() will create.  That's a stupid game.

Move the check into QAPISchema.check(), where the members are known.
Delegate the actual checking to new QAPIDoc.check().
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-38-git-send-email-armbru@redhat.com>

New test doc-bad-union-member.json shows we can fail to reject
documentation for nonexistent members.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-37-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-36-git-send-email-armbru@redhat.com>

Results in a more precise error location, but the real reason is
emptying out check_docs() step by step.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-35-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-34-git-send-email-armbru@redhat.com>

Move the check whether the doc matches the expression name from
check_definition_doc() to check_exprs().  This changes the error
location from the comment to the expression.  Makes sense as the
message talks about the expression: "Definition of '%s' follows
documentation for '%s'".  It's also a step towards getting rid of
check_docs().
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-33-git-send-email-armbru@redhat.com>

This fixes the errors uncovered by the previous commit.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-32-git-send-email-armbru@redhat.com>

New tests doc-before-include.json and doc-before-pragma.json show we
fail to reject a misplaced expression comment.

New test doc-no-symbol.json shows a bad error message.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1489582656-31133-31-git-send-email-armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>