Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933417AbaGVW0a (ORCPT ); Tue, 22 Jul 2014 18:26:30 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:44807 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932676AbaGVW01 (ORCPT ); Tue, 22 Jul 2014 18:26:27 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Bart Van Assche , Roland Dreier , Kamal Mostafa Subject: [PATCH 3.8 022/116] IB/srp: Fix a sporadic crash triggered by cable pulling Date: Tue, 22 Jul 2014 15:20:33 -0700 Message-Id: <1406067727-19683-23-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1406067727-19683-1-git-send-email-kamal@canonical.com> References: <1406067727-19683-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8.13.27 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit 024ca90151f5e4296d30f72c13ff9a075e23c9ec upstream. Avoid that the loops that iterate over the request ring can encounter a pointer to a SCSI command in req->scmnd that is no longer associated with that request. If the function srp_unmap_data() is invoked twice for a SCSI command that is not in flight then that would cause ib_fmr_pool_unmap() to be invoked with an invalid pointer as argument, resulting in a kernel oops. Reported-by: Sagi Grimberg Reference: http://thread.gmane.org/gmane.linux.drivers.rdma/19068/focus=19069 Signed-off-by: Bart Van Assche Reviewed-by: Sagi Grimberg Signed-off-by: Roland Dreier Signed-off-by: Kamal Mostafa --- drivers/infiniband/ulp/srp/ib_srp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index e070166..5682e8e 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -1410,6 +1410,12 @@ err_unmap: err_iu: srp_put_tx_iu(target, iu, SRP_IU_CMD); + /* + * Avoid that the loops that iterate over the request ring can + * encounter a dangling SCSI command pointer. + */ + req->scmnd = NULL; + spin_lock_irqsave(&target->lock, flags); list_add(&req->list, &target->free_reqs); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/