From patchwork Thu Jan 24 16:29:27 2013
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Subject: [BUG,RFC] block/vmdk.c: File name with space fails to open
Date: Thu, 24 Jan 2013 06:29:27 -0000
From: Philipp Hahn <hahn@univention.de>
X-Patchwork-Id: 215434
Message-Id: <201301241729.31903.hahn@univention.de>
To: qemu-devel@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>

Hello,

I tried to open a "twoGbMaxExtentSparse" VMDK file, which uses spaces in its 
own and for the referenced file names. This breaks in line 646 of 
block/vmdk.c because "%511s" stops at the first space and thus fname is 
incomplete:
        ret = sscanf(p, "%10s %" SCNd64 " %10s %511s %" SCNd64,
                access, &sectors, type, fname, &flat_offset);

I've only checked with our very old VMware workstation version, which refuses 
to create new images with unsupported characters with the following message:
> The characters !#%^&*><:;'"<>/? cannot be used.
So it looks like spaces are valid, at least we have several VMs with spaces in 
their name.

If the quotes around the file name are required, the simpliest solution would 
be to change %511s to "%511[^"]":

             goto next_line;

I don't know how portable %[ together with a maximum width is, because the 
manual page for sscanf() doesn't mention "max width" for "%[", but it works 
with Debian/GNU Linux Squeeze.

Sincerely
Philipp


diff --git a/block/vmdk.c b/block/vmdk.c
index 19298c2..045f6a1 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -641,7 +641,7 @@ static int vmdk_parse_extents(const char *desc, 
BlockDriverState *bs,
          * RW [size in sectors] SPARSE "file-name.vmdk"
          */
         flat_offset = -1;
-        ret = sscanf(p, "%10s %" SCNd64 " %10s %511s %" SCNd64,
+        ret = sscanf(p, "%10s %" SCNd64 " %10s \"%511[^\"]\" %" SCNd64,
                 access, &sectors, type, fname, &flat_offset);
         if (ret < 4 || strcmp(access, "RW")) {