[Qemu-devel] [PULL for-2.5 0/1] qemu-ga fix for 2.5

[Qemu-devel] [PULL for-2.5 0/1] qemu-ga fix for 2.5

[Michael Roth]

The following changes since commit 3c07587d49458341510360557c849e93e9afaf59:

  Merge remote-tracking branch 'remotes/dgibson/tags/ppc-next-20151111' into staging (2015-11-11 09:34:18 +0000)

are available in the git repository at:


  git://github.com/mdroth/qemu.git tags/qga-pull-2015-11-11-tag

for you to fetch changes up to 52074d0f662fc51293d4cde8077631f754784405:

  qga: fix append file open modes for win32 (2015-11-11 10:21:02 -0600)

----------------------------------------------------------------
qemu-ga patch queue

* fix for unintended overwriting of data on w32 using
  guest-file-open with append mode

----------------------------------------------------------------
Kirk Allan (1):
      qga: fix append file open modes for win32

 qga/commands-win32.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

[Qemu-devel] [PULL for-2.5 1/1] qga: fix append file open modes for win32

[Michael Roth]

From: Kirk Allan <kallan@suse.com>

For append file open modes, use FILE_APPEND_DATA for the desired access
for writing at the end of the file.

Version 2:
For "a+", "ab+", and "a+b" modes use FILE_APPEND_DATA|GENERIC_READ.
ORing in GENERIC_READ starts a read at the begining of the file.  All
writes will append to the end fo the file.

Added white space to maintain the alignment of the guest_file_open_modes[].

Signed-off-by: Kirk Allan <kallan@suse.com>
Cc: qemu-stable@nongnu.org
* use FILE_GENERIC_APPEND macro, which provides same semantics as
  FILE_APPEND_DATA, but retains other flags from GENERIC_WRITE
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-win32.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index a5306e7..41f6dd9 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -59,6 +59,7 @@ static struct {
     .filehandles = QTAILQ_HEAD_INITIALIZER(guest_file_state.filehandles),
 };
 
+#define FILE_GENERIC_APPEND (FILE_GENERIC_WRITE & ~FILE_WRITE_DATA)
 
 typedef struct OpenFlags {
     const char *forms;
@@ -66,20 +67,20 @@ typedef struct OpenFlags {
     DWORD creation_disposition;
 } OpenFlags;
 static OpenFlags guest_file_open_modes[] = {
-    {"r",   GENERIC_READ,               OPEN_EXISTING},
-    {"rb",  GENERIC_READ,               OPEN_EXISTING},
-    {"w",   GENERIC_WRITE,              CREATE_ALWAYS},
-    {"wb",  GENERIC_WRITE,              CREATE_ALWAYS},
-    {"a",   GENERIC_WRITE,              OPEN_ALWAYS  },
-    {"r+",  GENERIC_WRITE|GENERIC_READ, OPEN_EXISTING},
-    {"rb+", GENERIC_WRITE|GENERIC_READ, OPEN_EXISTING},
-    {"r+b", GENERIC_WRITE|GENERIC_READ, OPEN_EXISTING},
-    {"w+",  GENERIC_WRITE|GENERIC_READ, CREATE_ALWAYS},
-    {"wb+", GENERIC_WRITE|GENERIC_READ, CREATE_ALWAYS},
-    {"w+b", GENERIC_WRITE|GENERIC_READ, CREATE_ALWAYS},
-    {"a+",  GENERIC_WRITE|GENERIC_READ, OPEN_ALWAYS  },
-    {"ab+", GENERIC_WRITE|GENERIC_READ, OPEN_ALWAYS  },
-    {"a+b", GENERIC_WRITE|GENERIC_READ, OPEN_ALWAYS  }
+    {"r",   GENERIC_READ,                     OPEN_EXISTING},
+    {"rb",  GENERIC_READ,                     OPEN_EXISTING},
+    {"w",   GENERIC_WRITE,                    CREATE_ALWAYS},
+    {"wb",  GENERIC_WRITE,                    CREATE_ALWAYS},
+    {"a",   FILE_GENERIC_APPEND,              OPEN_ALWAYS  },
+    {"r+",  GENERIC_WRITE|GENERIC_READ,       OPEN_EXISTING},
+    {"rb+", GENERIC_WRITE|GENERIC_READ,       OPEN_EXISTING},
+    {"r+b", GENERIC_WRITE|GENERIC_READ,       OPEN_EXISTING},
+    {"w+",  GENERIC_WRITE|GENERIC_READ,       CREATE_ALWAYS},
+    {"wb+", GENERIC_WRITE|GENERIC_READ,       CREATE_ALWAYS},
+    {"w+b", GENERIC_WRITE|GENERIC_READ,       CREATE_ALWAYS},
+    {"a+",  FILE_GENERIC_APPEND|GENERIC_READ, OPEN_ALWAYS  },
+    {"ab+", FILE_GENERIC_APPEND|GENERIC_READ, OPEN_ALWAYS  },
+    {"a+b", FILE_GENERIC_APPEND|GENERIC_READ, OPEN_ALWAYS  }
 };
 
 static OpenFlags *find_open_flag(const char *mode_str)
-- 
1.9.1

Re: [Qemu-devel] [PULL for-2.5 0/1] qemu-ga fix for 2.5

[Peter Maydell]

On 11 November 2015 at 22:18, Michael Roth <mdroth@linux.vnet.ibm.com> wrote:
> The following changes since commit 3c07587d49458341510360557c849e93e9afaf59:
>
>   Merge remote-tracking branch 'remotes/dgibson/tags/ppc-next-20151111' into staging (2015-11-11 09:34:18 +0000)
>
> are available in the git repository at:
>
>
>   git://github.com/mdroth/qemu.git tags/qga-pull-2015-11-11-tag
>
> for you to fetch changes up to 52074d0f662fc51293d4cde8077631f754784405:
>
>   qga: fix append file open modes for win32 (2015-11-11 10:21:02 -0600)
>
> ----------------------------------------------------------------
> qemu-ga patch queue
>
> * fix for unintended overwriting of data on w32 using
>   guest-file-open with append mode
>
> ----------------------------------------------------------------

Applied, thanks.

-- PMM