From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa6.hgst.iphmx.com ([216.71.154.45]:54147 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760697AbdEXAfV (ORCPT ); Tue, 23 May 2017 20:35:21 -0400 From: Bart Van Assche To: "Martin K . Petersen" , James Bottomley CC: , , "Bart Van Assche" , Jens Axboe , "Christoph Hellwig" , Tejun Heo , Jan Kara , Hannes Reinecke , Subject: [PATCH 09/31] block: Avoid that blk_exit_rl() triggers a use-after-free Date: Tue, 23 May 2017 17:33:58 -0700 Message-ID: <20170524003420.5381-10-bart.vanassche@sandisk.com> In-Reply-To: <20170524003420.5381-1-bart.vanassche@sandisk.com> References: <20170524003420.5381-1-bart.vanassche@sandisk.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org Since the introduction of the .init_rq_fn() and .exit_rq_fn() it is essential that the memory allocated for struct request_queue stays around until all blk_exit_rl() calls have finished. Hence make blk_init_rl() take a reference on struct request_queue. This patch fixes the following crash: general protection fault: 0000 [#2] SMP CPU: 3 PID: 28 Comm: ksoftirqd/3 Tainted: G D 4.12.0-rc2-dbg+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 task: ffff88013a108040 task.stack: ffffc9000071c000 RIP: 0010:free_request_size+0x1a/0x30 RSP: 0018:ffffc9000071fd38 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b6b RBX: ffff880067362a88 RCX: 0000000000000003 RDX: ffff880067464178 RSI: ffff880067362a88 RDI: ffff880135ea4418 RBP: ffffc9000071fd40 R08: 0000000000000000 R09: 0000000100180009 R10: ffffc9000071fd38 R11: ffffffff81110800 R12: ffff88006752d3d8 R13: ffff88006752d3d8 R14: ffff88013a108040 R15: 000000000000000a FS: 0000000000000000(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa8ec1edb00 CR3: 0000000138ee8000 CR4: 00000000001406e0 Call Trace: mempool_destroy.part.10+0x21/0x40 mempool_destroy+0xe/0x10 blk_exit_rl+0x12/0x20 blkg_free+0x4d/0xa0 __blkg_release_rcu+0x59/0x170 rcu_process_callbacks+0x260/0x4e0 __do_softirq+0x116/0x250 smpboot_thread_fn+0x123/0x1e0 kthread+0x109/0x140 ret_from_fork+0x31/0x40 Fixes: commit e9c787e65c0c ("scsi: allocate scsi_cmnd structures as part of struct request") Signed-off-by: Bart Van Assche Cc: Jens Axboe Cc: Christoph Hellwig Cc: Tejun Heo Cc: Jan Kara Cc: Hannes Reinecke Cc: # v4.11+ --- block/blk-cgroup.c | 2 +- block/blk-core.c | 10 ++++++++-- block/blk-sysfs.c | 2 +- block/blk.h | 2 +- 4 files changed, 11 insertions(+), 5 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 7c2947128f58..0480892e97e5 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -74,7 +74,7 @@ static void blkg_free(struct blkcg_gq *blkg) blkcg_policy[i]->pd_free_fn(blkg->pd[i]); if (blkg->blkcg != &blkcg_root) - blk_exit_rl(&blkg->rl); + blk_exit_rl(blkg->q, &blkg->rl); blkg_rwstat_exit(&blkg->stat_ios); blkg_rwstat_exit(&blkg->stat_bytes); diff --git a/block/blk-core.c b/block/blk-core.c index c7068520794b..55a7b76db7c2 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -648,13 +648,19 @@ int blk_init_rl(struct request_list *rl, struct request_queue *q, if (!rl->rq_pool) return -ENOMEM; + if (rl != &q->root_rl) + blk_get_queue(q); + return 0; } -void blk_exit_rl(struct request_list *rl) +void blk_exit_rl(struct request_queue *q, struct request_list *rl) { - if (rl->rq_pool) + if (rl->rq_pool) { mempool_destroy(rl->rq_pool); + if (rl != &q->root_rl) + blk_put_queue(q); + } } struct request_queue *blk_alloc_queue(gfp_t gfp_mask) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 504fee940052..2ff8842f0dc1 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -809,7 +809,7 @@ static void blk_release_queue(struct kobject *kobj) blk_free_queue_stats(q->stats); - blk_exit_rl(&q->root_rl); + blk_exit_rl(q, &q->root_rl); if (q->queue_tags) __blk_queue_free_tags(q); diff --git a/block/blk.h b/block/blk.h index 2ed70228e44f..83c8e1100525 100644 --- a/block/blk.h +++ b/block/blk.h @@ -59,7 +59,7 @@ void blk_free_flush_queue(struct blk_flush_queue *q); int blk_init_rl(struct request_list *rl, struct request_queue *q, gfp_t gfp_mask); -void blk_exit_rl(struct request_list *rl); +void blk_exit_rl(struct request_queue *q, struct request_list *rl); void blk_rq_bio_prep(struct request_queue *q, struct request *rq, struct bio *bio); void blk_queue_bypass_start(struct request_queue *q); -- 2.12.2 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: [PATCH 09/31] block: Avoid that blk_exit_rl() triggers a use-after-free Date: Tue, 23 May 2017 17:33:58 -0700 Message-ID: <20170524003420.5381-10-bart.vanassche@sandisk.com> References: <20170524003420.5381-1-bart.vanassche@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20170524003420.5381-1-bart.vanassche@sandisk.com> Sender: stable-owner@vger.kernel.org To: "Martin K . Petersen" , James Bottomley Cc: linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, Bart Van Assche , Jens Axboe , Christoph Hellwig , Tejun Heo , Jan Kara , Hannes Reinecke , stable@vger.kernel.org List-Id: linux-scsi@vger.kernel.org Since the introduction of the .init_rq_fn() and .exit_rq_fn() it is essential that the memory allocated for struct request_queue stays around until all blk_exit_rl() calls have finished. Hence make blk_init_rl() take a reference on struct request_queue. This patch fixes the following crash: general protection fault: 0000 [#2] SMP CPU: 3 PID: 28 Comm: ksoftirqd/3 Tainted: G D 4.12.0-rc2-dbg+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 task: ffff88013a108040 task.stack: ffffc9000071c000 RIP: 0010:free_request_size+0x1a/0x30 RSP: 0018:ffffc9000071fd38 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b6b RBX: ffff880067362a88 RCX: 0000000000000003 RDX: ffff880067464178 RSI: ffff880067362a88 RDI: ffff880135ea4418 RBP: ffffc9000071fd40 R08: 0000000000000000 R09: 0000000100180009 R10: ffffc9000071fd38 R11: ffffffff81110800 R12: ffff88006752d3d8 R13: ffff88006752d3d8 R14: ffff88013a108040 R15: 000000000000000a FS: 0000000000000000(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa8ec1edb00 CR3: 0000000138ee8000 CR4: 00000000001406e0 Call Trace: mempool_destroy.part.10+0x21/0x40 mempool_destroy+0xe/0x10 blk_exit_rl+0x12/0x20 blkg_free+0x4d/0xa0 __blkg_release_rcu+0x59/0x170 rcu_process_callbacks+0x260/0x4e0 __do_softirq+0x116/0x250 smpboot_thread_fn+0x123/0x1e0 kthread+0x109/0x140 ret_from_fork+0x31/0x40 Fixes: commit e9c787e65c0c ("scsi: allocate scsi_cmnd structures as part of struct request") Signed-off-by: Bart Van Assche Cc: Jens Axboe Cc: Christoph Hellwig Cc: Tejun Heo Cc: Jan Kara Cc: Hannes Reinecke Cc: # v4.11+ --- block/blk-cgroup.c | 2 +- block/blk-core.c | 10 ++++++++-- block/blk-sysfs.c | 2 +- block/blk.h | 2 +- 4 files changed, 11 insertions(+), 5 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 7c2947128f58..0480892e97e5 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -74,7 +74,7 @@ static void blkg_free(struct blkcg_gq *blkg) blkcg_policy[i]->pd_free_fn(blkg->pd[i]); if (blkg->blkcg != &blkcg_root) - blk_exit_rl(&blkg->rl); + blk_exit_rl(blkg->q, &blkg->rl); blkg_rwstat_exit(&blkg->stat_ios); blkg_rwstat_exit(&blkg->stat_bytes); diff --git a/block/blk-core.c b/block/blk-core.c index c7068520794b..55a7b76db7c2 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -648,13 +648,19 @@ int blk_init_rl(struct request_list *rl, struct request_queue *q, if (!rl->rq_pool) return -ENOMEM; + if (rl != &q->root_rl) + blk_get_queue(q); + return 0; } -void blk_exit_rl(struct request_list *rl) +void blk_exit_rl(struct request_queue *q, struct request_list *rl) { - if (rl->rq_pool) + if (rl->rq_pool) { mempool_destroy(rl->rq_pool); + if (rl != &q->root_rl) + blk_put_queue(q); + } } struct request_queue *blk_alloc_queue(gfp_t gfp_mask) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 504fee940052..2ff8842f0dc1 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -809,7 +809,7 @@ static void blk_release_queue(struct kobject *kobj) blk_free_queue_stats(q->stats); - blk_exit_rl(&q->root_rl); + blk_exit_rl(q, &q->root_rl); if (q->queue_tags) __blk_queue_free_tags(q); diff --git a/block/blk.h b/block/blk.h index 2ed70228e44f..83c8e1100525 100644 --- a/block/blk.h +++ b/block/blk.h @@ -59,7 +59,7 @@ void blk_free_flush_queue(struct blk_flush_queue *q); int blk_init_rl(struct request_list *rl, struct request_queue *q, gfp_t gfp_mask); -void blk_exit_rl(struct request_list *rl); +void blk_exit_rl(struct request_queue *q, struct request_list *rl); void blk_rq_bio_prep(struct request_queue *q, struct request *rq, struct bio *bio); void blk_queue_bypass_start(struct request_queue *q); -- 2.12.2