From 29fae90baa14f518407fe7c437d38af768a3134c Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Fri, 26 Feb 2021 18:26:55 +0000 Subject: [PATCH] tools/xenstored: Avoid dereferencing a NULL pointer if LiveUpdate is failing In case of failure in do_lu_start(), XenStored will first free lu_start and then try to dereference it. This will result to a NULL dereference as the destruction callback will set lu_start to NULL. The crash can be avoided by freeing lu_start *after* the reply has been set. Fixes: af216a99fb4a ("tools/xenstore: add the basic framework for doing the live update") Signed-off-by: Julien Grall Reviewed-by: Juergen Gross Release-Acked-by: Ian Jackson --- tools/xenstore/xenstored_control.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/xenstore/xenstored_control.c b/tools/xenstore/xenstored_control.c index 653890f2d9..766b243839 100644 --- a/tools/xenstore/xenstored_control.c +++ b/tools/xenstore/xenstored_control.c @@ -657,9 +657,8 @@ static bool do_lu_start(struct delayed_request *req) /* We will reach this point only in case of failure. */ out: - talloc_free(lu_status); - send_reply(lu_status->conn, XS_CONTROL, ret, strlen(ret) + 1); + talloc_free(lu_status); return true; } -- 2.30.2