[PATCH] xen: don't continue xenstore initialization in case of errors

From: Stefano Stabellini
Date: Fri Nov 12 2021 - 16:47:16 EST


From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx>

In case of errors in xenbus_init (e.g. missing xen_store_gfn parameter),
we goto out_error but we forget to reset xen_store_domain_type to
XS_UNKNOWN. As a consequence xenbus_probe_initcall and other initcalls
will still try to initialize xenstore resulting into a crash at boot.

[ 2.479830] Call trace:
[ 2.482314] xb_init_comms+0x18/0x150
[ 2.486354] xs_init+0x34/0x138
[ 2.489786] xenbus_probe+0x4c/0x70
[ 2.498432] xenbus_probe_initcall+0x2c/0x7c
[ 2.503944] do_one_initcall+0x54/0x1b8
[ 2.507358] kernel_init_freeable+0x1ac/0x210
[ 2.511617] kernel_init+0x28/0x130
[ 2.516112] ret_from_fork+0x10/0x20

Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx>
---
drivers/xen/xenbus/xenbus_probe.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index bd003ca8acbe..34abf2b5967b 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -983,8 +983,10 @@ static int __init xenbus_init(void)
*/
proc_create_mount_point("xen");
#endif
+ return err;

out_error:
+ xen_store_domain_type = XS_UNKNOWN;
return err;
}

--
2.25.1