[PATCH 1/2] Drivers: hv: vmbus: check the creation_status in vmbus_establish_gpadl()

kys
2018-11-26T02:31:02Z

From: Dexuan Cui <decui@microsoft.com>

This is a longstanding issue: if the vmbus upper-layer drivers try to
consume too many GPADLs, the host may return with an error
0xC0000044 (STATUS_QUOTA_EXCEEDED), but currently we forget to check
the creation_status, and hence we can pass an invalid GPADL handle
into the OPEN_CHANNEL message, and get an error code 0xc0000225 in
open_info->response.open_result.status, and finally we hang in
vmbus_open() -> "goto error_free_info" -> vmbus_teardown_gpadl().

With this patch, we can exit gracefully on STATUS_QUOTA_EXCEEDED.

Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/hv/channel.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index f96a77b18bb9..ce0ba2062723 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -516,6 +516,14 @@ int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
}
wait_for_completion(&msginfo->waitevent);

+ if (msginfo->response.gpadl_created.creation_status != 0) {
+ pr_err("Failed to establish GPADL: err = 0x%x\n",
+ msginfo->response.gpadl_created.creation_status);
+
+ ret = -EDQUOT;
+ goto cleanup;
+ }
+
if (channel->rescind) {
ret = -ENODEV;
goto cleanup;
--
2.19.1