[xen master] Revert "evtchn: refuse EVTCHNOP_status for Xen-bound event channels"

[patchbot@xxxxxxx]

commit 2d8d7481ca261d86c33e27e2294ed8c9ef5a0fc3
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Tue Apr 2 15:50:19 2024 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Sat May 11 00:13:43 2024 +0100

    Revert "evtchn: refuse EVTCHNOP_status for Xen-bound event channels"
    
    The commit makes a claim without justification.
    
    The claim is false; it broke lsevtchn in dom0, a debugging utility which
    absolutely does care about all of the domain's event channels.
    
    Whether to return information about a xen-owned evtchn is a matter of 
policy,
    and it's not acceptable to subvert Xen's security subsystem on the decision.
    
    This reverts commit f60ab5337f968e2f10c639ab59db7afb0fe4f7c3.
    
    Fixes: f60ab5337f96 ("evtchn: refuse EVTCHNOP_status for Xen-bound event 
channels")
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Acked-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
---
 xen/common/event_channel.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index aceee0695f..a67feff989 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -1041,12 +1041,6 @@ int evtchn_status(evtchn_status_t *status)
 
     read_lock(&d->event_lock);
 
-    if ( consumer_is_xen(chn) )
-    {
-        rc = -EACCES;
-        goto out;
-    }
-
     rc = xsm_evtchn_status(XSM_TARGET, d, chn);
     if ( rc )
         goto out;
--
generated by git-patchbot for /home/xen/git/xen.git#master