diff options
authorSimon Farnsworth <>2010-06-22 10:13:30 +0100
committerKeith Packard <>2010-06-22 11:42:33 -0700
commit660f6ab5494a728c3ca7ba00c305e9ff06c8ecb2 (patch)
parent82d41ada993d8cbdcdfea878d1a5b031afe4e593 (diff)
Don't crash when asked if a client that has disconnected was local
ProcDRI2Dispatch uses LocalClient to determine if it's safe to respond to a client that has made DRI2 requests which aren't sensible for remote clients (anything but version). When the client has disappeared mid-request stream (e.g. as a result of a kill -9, or a client-side bug), LocalClient causes the X server to follow suit, as ((OsCommPtr)client->osPrivate)->trans_conn is NULL at this point. The simple and obvious fix is to just return "not local" when trans_conn is NULL, which fixes the crash I was seeing; however Keith Packard pointed out that just checking trans_conn isn't enough; quoting Keith: "This looks almost right to me -- I reviewed the os code to see when _XSERVTransClose is called (which is what frees the trans_conn data) and found that every place which called that immediately set trans_conn to NULL, except for the call in CloseDownFileDescriptor which is only called from CloseDownConnection and which is immediately followed by freeing the OsCommRec and setting client->osPrivate to NULL. So, I'd suggest checking client->osPrivate in addition to the above check." Signed-off-by: Simon Farnsworth <> Reviewed-by: Keith Packard <> Signed-off-by: Keith Packard <>
1 files changed, 5 insertions, 0 deletions
diff --git a/os/access.c b/os/access.c
index 5f485c92f..027925927 100644
--- a/os/access.c
+++ b/os/access.c
@@ -1123,6 +1123,11 @@ Bool LocalClient(ClientPtr client)
pointer addr;
register HOST *host;
+ if (!client->osPrivate)
+ return FALSE;
+ if (!((OsCommPtr)client->osPrivate)->trans_conn)
+ return FALSE;
if (!_XSERVTransGetPeerAddr (((OsCommPtr)client->osPrivate)->trans_conn,
&notused, &alen, &from))