From d3b26dd7cb0e3433bfd3c1d4dcf74c6039bb49fb Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Thu, 2 Aug 2018 03:08:23 +0000 Subject: Drivers: hv: vmbus: Reset the channel callback in vmbus_onoffer_rescind() Before setting channel->rescind in vmbus_rescind_cleanup(), we should make sure the channel callback won't run any more, otherwise a high-level driver like pci_hyperv, which may be infinitely waiting for the host VSP's response and notices the channel has been rescinded, can't safely give up: e.g., in hv_pci_protocol_negotiation() -> wait_for_response(), it's unsafe to exit from wait_for_response() and proceed with the on-stack variable "comp_pkt" popped. The issue was originally spotted by Michael Kelley . In vmbus_close_internal(), the patch also minimizes the range protected by disabling/enabling channel->callback_event: we don't really need that for the whole function. Signed-off-by: Dexuan Cui Reviewed-by: Michael Kelley Cc: stable@vger.kernel.org Cc: K. Y. Srinivasan Cc: Stephen Hemminger Cc: Michael Kelley Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- include/linux/hyperv.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 2330f08062c7..efda23cf32c7 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -1061,6 +1061,8 @@ extern int vmbus_establish_gpadl(struct vmbus_channel *channel, extern int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle); +void vmbus_reset_channel_cb(struct vmbus_channel *channel); + extern int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer, u32 bufferlen, -- cgit v1.2.3