diff options
authorMichal Srb <>2017-05-24 15:54:39 +0300
committerPeter Hutterer <>2017-06-19 11:58:44 +1000
commit05442de962d3dc624f79fc1a00eca3ffc5489ced (patch)
parentd82c3cee02a99cf7861d1effaa5c7d38683a7783 (diff)
Xi: Zero target buffer in SProcXSendExtensionEvent.
Make sure that the xEvent eventT is initialized with zeros, the same way as in SProcSendEvent. Some event swapping functions do not overwrite all 32 bytes of xEvent structure, for example XSecurityAuthorizationRevoked. Two cooperating clients, one swapped and the other not, can send XSecurityAuthorizationRevoked event to each other to retrieve old stack data from X server. This can be potentialy misused to go around ASLR or stack-protector. Signed-off-by: Michal Srb <> Reviewed-by: Peter Hutterer <> Signed-off-by: Peter Hutterer <>
1 files changed, 1 insertions, 1 deletions
diff --git a/Xi/sendexev.c b/Xi/sendexev.c
index 11d82029f..1cf118ab6 100644
--- a/Xi/sendexev.c
+++ b/Xi/sendexev.c
@@ -78,7 +78,7 @@ SProcXSendExtensionEvent(ClientPtr client)
CARD32 *p;
int i;
- xEvent eventT;
+ xEvent eventT = { .u.u.type = 0 };
xEvent *eventP;
EventSwapPtr proc;