From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:59316) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T1XkU-0006lh-QC for qemu-devel@nongnu.org; Wed, 15 Aug 2012 03:10:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T1Xjq-0007yU-Ji for qemu-devel@nongnu.org; Wed, 15 Aug 2012 03:10:38 -0400 Received: from mail.profihost.ag ([85.158.179.208]:42352) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T1Xjq-0007yP-9z for qemu-devel@nongnu.org; Wed, 15 Aug 2012 03:09:58 -0400 From: Stefan Priebe Date: Wed, 15 Aug 2012 09:09:54 +0200 Message-Id: <1345014594-6020-2-git-send-email-s.priebe@profihost.ag> In-Reply-To: <1345014594-6020-1-git-send-email-s.priebe@profihost.ag> References: <1345014594-6020-1-git-send-email-s.priebe@profihost.ag> Subject: [Qemu-devel] [PATCH] PATCH V2: fix NULL dereferences / races between task completition and abort List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: ronniesahlberg@gmail.com, Stefan Priebe Signed-off-by: Stefan Priebe --- block/iscsi.c | 55 +++++++++++++++++++++++-------------------------------- 1 files changed, 23 insertions(+), 32 deletions(-) diff --git a/block/iscsi.c b/block/iscsi.c index 12ca76d..1c8b049 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -76,6 +76,10 @@ static void iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data, void *private_data) { + IscsiAIOCB *acb = (IscsiAIOCB *)private_data; + + scsi_free_scsi_task(acb->task); + acb->task = NULL; } static void @@ -84,15 +88,15 @@ iscsi_aio_cancel(BlockDriverAIOCB *blockacb) IscsiAIOCB *acb = (IscsiAIOCB *)blockacb; IscsiLun *iscsilun = acb->iscsilun; - acb->common.cb(acb->common.opaque, -ECANCELED); acb->canceled = 1; - /* send a task mgmt call to the target to cancel the task on the target */ - iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task, - iscsi_abort_task_cb, NULL); + acb->common.cb(acb->common.opaque, -ECANCELED); - /* then also cancel the task locally in libiscsi */ - iscsi_scsi_task_cancel(iscsilun->iscsi, acb->task); + /* send a task mgmt call to the target to cancel the task on the target + * this also cancels the task in libiscsi + */ + iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task, + iscsi_abort_task_cb, &acb); } static AIOPool iscsi_aio_pool = { @@ -179,11 +183,18 @@ iscsi_readv_writev_bh_cb(void *p) qemu_bh_delete(acb->bh); - if (acb->canceled == 0) { + if (!acb->canceled) { acb->common.cb(acb->common.opaque, acb->status); } qemu_aio_release(acb); + + if (acb->canceled) { + return; + } + + scsi_free_scsi_task(acb->task); + acb->task = NULL; } @@ -197,10 +208,8 @@ iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status, g_free(acb->buf); - if (acb->canceled != 0) { + if (acb->canceled) { qemu_aio_release(acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; return; } @@ -212,8 +221,6 @@ iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status, } iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; } static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun) @@ -298,10 +305,8 @@ iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status, trace_iscsi_aio_read16_cb(iscsi, status, acb, acb->canceled); - if (acb->canceled != 0) { + if (acb->canceled) { qemu_aio_release(acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; return; } @@ -313,8 +318,6 @@ iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status, } iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; } static BlockDriverAIOCB * @@ -414,10 +417,8 @@ iscsi_synccache10_cb(struct iscsi_context *iscsi, int status, { IscsiAIOCB *acb = opaque; - if (acb->canceled != 0) { + if (acb->canceled) { qemu_aio_release(acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; return; } @@ -429,8 +430,6 @@ iscsi_synccache10_cb(struct iscsi_context *iscsi, int status, } iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; } static BlockDriverAIOCB * @@ -468,10 +467,8 @@ iscsi_unmap_cb(struct iscsi_context *iscsi, int status, { IscsiAIOCB *acb = opaque; - if (acb->canceled != 0) { + if (acb->canceled) { qemu_aio_release(acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; return; } @@ -483,8 +480,6 @@ iscsi_unmap_cb(struct iscsi_context *iscsi, int status, } iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; } static BlockDriverAIOCB * @@ -528,10 +523,8 @@ iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status, { IscsiAIOCB *acb = opaque; - if (acb->canceled != 0) { + if (acb->canceled) { qemu_aio_release(acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; return; } @@ -560,8 +553,6 @@ iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status, } iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb); - scsi_free_scsi_task(acb->task); - acb->task = NULL; } static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs, -- 1.7.2.5