Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753923AbcDZXNw (ORCPT ); Tue, 26 Apr 2016 19:13:52 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39770 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753696AbcDZXNh (ORCPT ); Tue, 26 Apr 2016 19:13:37 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Doug Ledford" , "Sagi Grimberg" , "Bart Van Assche" , "Christoph Hellwig" , "Alex Estrin" , "Nicholas Bellinger" Date: Wed, 27 Apr 2016 01:02:21 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 052/217] IB/srpt: Simplify srpt_handle_tsk_mgmt() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8426:ae4:c500:9cba:69ae:962d:6167 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3945 Lines: 121 3.16.35-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit 51093254bf879bc9ce96590400a87897c7498463 upstream. Let the target core check task existence instead of the SRP target driver. Additionally, let the target core check the validity of the task management request instead of the ib_srpt driver. This patch fixes the following kernel crash: BUG: unable to handle kernel NULL pointer dereference at 0000000000000001 IP: [] srpt_handle_new_iu+0x6d7/0x790 [ib_srpt] Oops: 0002 [#1] SMP Call Trace: [] srpt_process_completion+0xde/0x570 [ib_srpt] [] srpt_compl_thread+0x13f/0x160 [ib_srpt] [] kthread+0xcf/0xe0 [] ret_from_fork+0x7c/0xb0 Signed-off-by: Bart Van Assche Fixes: 3e4f574857ee ("ib_srpt: Convert TMR path to target_submit_tmr") Tested-by: Alex Estrin Reviewed-by: Christoph Hellwig Cc: Nicholas Bellinger Cc: Sagi Grimberg Signed-off-by: Doug Ledford [bwh: Backported to 3.16: deleted code is slightly different] Signed-off-by: Ben Hutchings --- drivers/infiniband/ulp/srpt/ib_srpt.c | 59 +---------------------------------- 1 file changed, 1 insertion(+), 58 deletions(-) --- a/drivers/infiniband/ulp/srpt/ib_srpt.c +++ b/drivers/infiniband/ulp/srpt/ib_srpt.c @@ -1744,47 +1744,6 @@ send_sense: return -1; } -/** - * srpt_rx_mgmt_fn_tag() - Process a task management function by tag. - * @ch: RDMA channel of the task management request. - * @fn: Task management function to perform. - * @req_tag: Tag of the SRP task management request. - * @mgmt_ioctx: I/O context of the task management request. - * - * Returns zero if the target core will process the task management - * request asynchronously. - * - * Note: It is assumed that the initiator serializes tag-based task management - * requests. - */ -static int srpt_rx_mgmt_fn_tag(struct srpt_send_ioctx *ioctx, u64 tag) -{ - struct srpt_device *sdev; - struct srpt_rdma_ch *ch; - struct srpt_send_ioctx *target; - int ret, i; - - ret = -EINVAL; - ch = ioctx->ch; - BUG_ON(!ch); - BUG_ON(!ch->sport); - sdev = ch->sport->sdev; - BUG_ON(!sdev); - spin_lock_irq(&sdev->spinlock); - for (i = 0; i < ch->rq_size; ++i) { - target = ch->ioctx_ring[i]; - if (target->cmd.se_lun == ioctx->cmd.se_lun && - target->tag == tag && - srpt_get_cmd_state(target) != SRPT_STATE_DONE) { - ret = 0; - /* now let the target core abort &target->cmd; */ - break; - } - } - spin_unlock_irq(&sdev->spinlock); - return ret; -} - static int srp_tmr_to_tcm(int fn) { switch (fn) { @@ -1819,7 +1778,6 @@ static void srpt_handle_tsk_mgmt(struct struct se_cmd *cmd; struct se_session *sess = ch->sess; uint64_t unpacked_lun; - uint32_t tag = 0; int tcm_tmr; int rc; @@ -1835,25 +1793,10 @@ static void srpt_handle_tsk_mgmt(struct srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT); send_ioctx->tag = srp_tsk->tag; tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func); - if (tcm_tmr < 0) { - send_ioctx->cmd.se_tmr_req->response = - TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED; - goto fail; - } unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_tsk->lun, sizeof(srp_tsk->lun)); - - if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK) { - rc = srpt_rx_mgmt_fn_tag(send_ioctx, srp_tsk->task_tag); - if (rc < 0) { - send_ioctx->cmd.se_tmr_req->response = - TMR_TASK_DOES_NOT_EXIST; - goto fail; - } - tag = srp_tsk->task_tag; - } rc = target_submit_tmr(&send_ioctx->cmd, sess, NULL, unpacked_lun, - srp_tsk, tcm_tmr, GFP_KERNEL, tag, + srp_tsk, tcm_tmr, GFP_KERNEL, srp_tsk->task_tag, TARGET_SCF_ACK_KREF); if (rc != 0) { send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED;