If a guest sends an empty string paramater to any 9P operation, the current
code unmarshals it into a V9fsString equal to { .size = 0, .data = NULL }.
This is unfortunate because it can cause NULL pointer dereference to happen
at various locations in the 9pfs code. And we don't want to check str->data
everywhere we pass it to strcmp() or any other function which expects a
dereferenceable pointer.
This patch enforces the allocation of genuine C empty strings instead, so
callers don't have to bother.
Out of all v9fs_iov_vunmarshal() users, only v9fs_xattrwalk() checks if
the returned string is empty. It now uses v9fs_string_size() since
name.data cannot be NULL anymore.
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
[groug, rewritten title and changelog,
fix empty string check in v9fs_xattrwalk()]
Signed-off-by: Greg Kurz <groug@kaod.org>
Don't use the cpu_to_*w() functions, which we are trying to deprecate.
Instead just use cpu_to_*() to do the byteswap, which brings the
code in the marshal function in line with that in the unmarshal.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1467908460-27048-2-git-send-email-peter.maydell@linaro.org
The <sys/uio.h> system header doesn't exist on all host platforms. Code
should include "qemu/osdep.h" instead to avoid build breaks on plafforms
that don't define CONFIG_IOVEC (like win32, if it is to support 9p one day).
Acked-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Michael Fritscher <michael@fritscher.net>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Remove glib.h includes, as it is provided by osdep.h.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
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 <peter.maydell@linaro.org>
Message-id: 1453832250-766-18-git-send-email-peter.maydell@linaro.org
Factor out v9fs_iov_v{,un}marshal. Implement pdu_{,un}marshal with those
functions.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
And rename v9fs_marshal to v9fs_iov_marshal, v9fs_unmarshal to
v9fs_iov_unmarshal.
The rationale behind this change is that, this marshalling interface is
used both by virtio and proxy helper. Renaming files and functions to
reflect the true nature of this interface.
Xen transport is going to have its own marshalling interface.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
