On 30.06.2014 09:33, Gerd Hoffmann wrote:
On So, 2014-06-29 at 14:16 +0200, Peter Lieven wrote:
Hi,
while debugging a VNC issue I found this:
case VNC_MSG_CLIENT_CUT_TEXT:
if (len == 1)
return 8;
if (len == 8) {
uint32_t dlen = read_u32(data, 4);
if (dlen > 0)
return 8 + dlen;
}
client_cut_text(vs, read_u32(data, 4), data + 8);
break;
in protocol_client_msg().
Is this really a good idea? This allows for letting the vs->input buffer to grow
up to 2^32 + 8 byte which will possibly result in an out of memory condition.
Applying a limit there looks reasonable to me. Patches welcome.
As this is text only a megabyte should be more than enough for all
practical purposes. Question is what to do when the limit is exceeded?
Disconnect? Read & throw away?
I would also think something in the order of megabytes should be fine.
I would vote for disconnect as soon as the limit specified is too big. Otherwise
we had to rewrite the whole receive logic which could introduce additional
bugs.
Peter
--
Mit freundlichen Grüßen
Peter Lieven
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