Hi Juergen,
On 24/06/2021 10:17, Juergen Gross wrote:
On 24.06.21 10:12, Julien Grall wrote:
Hi Juergen,
On 22/06/2021 11:23, Juergen Gross wrote:
On 17.06.21 19:38, Julien Grall wrote:
From: Julien GralL <jgr...@amazon.com>
As Live-Update is asynchronous, it is possible to receive a request to
cancel it (either on the same connection or from a different one).
Currently, this will crash xenstored because do_lu_start() assumes
lu_status will be valid. This is not the case when Live-Update has been
cancelled. This will result to dereference a NULL pointer and
crash Xenstored.
Rework do_lu_start() to check if lu_status is NULL and return an
error in this case.
Fixes: af216a99fb ("tools/xenstore: add the basic framework for doing
the live update")
Signed-off-by: Julien Grall <jgr...@amazon.com>
----
This is currently based on top of:
https://lore.kernel.org/xen-devel/20210616144324.31652-1-jul...@xen.org
This can be re-ordered if necessary.
---
tools/xenstore/xenstored_control.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/tools/xenstore/xenstored_control.c
b/tools/xenstore/xenstored_control.c
index a045f102a420..37a3d39f20b5 100644
--- a/tools/xenstore/xenstored_control.c
+++ b/tools/xenstore/xenstored_control.c
@@ -696,7 +696,18 @@ static bool do_lu_start(struct delayed_request
*req)
time_t now = time(NULL);
const char *ret;
struct buffered_data *saved_in;
- struct connection *conn = lu_status->conn;
+ struct connection *conn = req->data;
+
+ /*
+ * Cancellation may have been requested asynchronously. In this
+ * case, lu_status will be NULL.
+ */
+ if (!lu_status) {
+ ret = "Cancellation was
requested";
+ conn = req->data;
This will set conn to the same value it already has.
Ah yes. I will drop this line.
Also, I took the opportunity to replace
} else
assert(...)
with just
assert(...)
This should improve a bit the readability. Let me know if you want me
to resend the patch for that.
I guess you are planning to do the commit?
That's my plan.
If yes, there is no need for resending the patch.
Thanks!
Cheers,
--
Julien Grall
