[PATCH V4 5/6] blk-mq: prepare for implementing hctx table via xarray
From: Ming Lei <hidden>
Date: 2022-03-08 07:33:34
Subsystem:
block layer, rnbd block drivers, the rest · Maintainers:
Jens Axboe, Md. Haris Iqbal, Jack Wang, Linus Torvalds
It is inevitable to cause use-after-free on q->queue_hw_ctx between queue_for_each_hw_ctx() and blk_mq_update_nr_hw_queues(). And converting to xarray can fix the uaf, meantime code gets cleaner. Prepare for converting q->queue_hctx_ctx into xarray, one thing is that xa_for_each() can only accept 'unsigned long' as index, so changes type of hctx index of queue_for_each_hw_ctx() into 'unsigned long'. Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <redacted> --- block/blk-mq-debugfs.c | 6 +++--- block/blk-mq-sched.c | 9 +++++---- block/blk-mq-sysfs.c | 16 ++++++++++------ block/blk-mq-tag.c | 2 +- block/blk-mq.c | 30 ++++++++++++++++-------------- drivers/block/rnbd/rnbd-clt.c | 2 +- 6 files changed, 36 insertions(+), 29 deletions(-)
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 3a790eb4995c..e2880f6deb34 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c@@ -707,7 +707,7 @@ static void debugfs_create_files(struct dentry *parent, void *data, void blk_mq_debugfs_register(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; debugfs_create_files(q->debugfs_dir, q, blk_mq_debugfs_queue_attrs);
@@ -780,7 +780,7 @@ void blk_mq_debugfs_unregister_hctx(struct blk_mq_hw_ctx *hctx) void blk_mq_debugfs_register_hctxs(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) blk_mq_debugfs_register_hctx(q, hctx);
@@ -789,7 +789,7 @@ void blk_mq_debugfs_register_hctxs(struct request_queue *q) void blk_mq_debugfs_unregister_hctxs(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) blk_mq_debugfs_unregister_hctx(hctx);
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index 55488ba97823..e6ad8f761474 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c@@ -515,7 +515,7 @@ static void blk_mq_exit_sched_shared_tags(struct request_queue *queue) static void blk_mq_sched_tags_teardown(struct request_queue *q, unsigned int flags) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) { if (hctx->sched_tags) {
@@ -550,9 +550,10 @@ static int blk_mq_init_sched_shared_tags(struct request_queue *queue) int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e) { - unsigned int i, flags = q->tag_set->flags; + unsigned int flags = q->tag_set->flags; struct blk_mq_hw_ctx *hctx; struct elevator_queue *eq; + unsigned long i; int ret; if (!e) {
@@ -618,7 +619,7 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e) void blk_mq_sched_free_rqs(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; if (blk_mq_is_shared_tags(q->tag_set->flags)) { blk_mq_free_rqs(q->tag_set, q->sched_shared_tags,
@@ -635,7 +636,7 @@ void blk_mq_sched_free_rqs(struct request_queue *q) void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e) { struct blk_mq_hw_ctx *hctx; - unsigned int i; + unsigned long i; unsigned int flags = 0; queue_for_each_hw_ctx(q, hctx, i) {
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 674786574075..c08426975856 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c@@ -206,7 +206,7 @@ static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) void blk_mq_unregister_dev(struct device *dev, struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; lockdep_assert_held(&q->sysfs_dir_lock);
@@ -255,7 +255,8 @@ void blk_mq_sysfs_init(struct request_queue *q) int __blk_mq_register_dev(struct device *dev, struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int ret, i; + unsigned long i, j; + int ret; WARN_ON_ONCE(!q->kobj.parent); lockdep_assert_held(&q->sysfs_dir_lock);
@@ -278,8 +279,10 @@ int __blk_mq_register_dev(struct device *dev, struct request_queue *q) return ret; unreg: - while (--i >= 0) - blk_mq_unregister_hctx(q->queue_hw_ctx[i]); + queue_for_each_hw_ctx(q, hctx, j) { + if (j < i) + blk_mq_unregister_hctx(hctx); + } kobject_uevent(q->mq_kobj, KOBJ_REMOVE); kobject_del(q->mq_kobj);
@@ -290,7 +293,7 @@ int __blk_mq_register_dev(struct device *dev, struct request_queue *q) void blk_mq_sysfs_unregister(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; mutex_lock(&q->sysfs_dir_lock); if (!q->mq_sysfs_init_done)
@@ -306,7 +309,8 @@ void blk_mq_sysfs_unregister(struct request_queue *q) int blk_mq_sysfs_register(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i, ret = 0; + unsigned long i; + int ret = 0; mutex_lock(&q->sysfs_dir_lock); if (!q->mq_sysfs_init_done)
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 0fd409b8e86e..1850a4225e12 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c@@ -515,7 +515,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_tag_iter_fn *fn, bt_for_each(NULL, q, btags, fn, priv, false); } else { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) { struct blk_mq_tags *tags = hctx->tags;
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 57ae9df0f4dc..bffdd71c670d 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c@@ -312,7 +312,7 @@ EXPORT_SYMBOL_GPL(blk_mq_unquiesce_queue); void blk_mq_wake_waiters(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - unsigned int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) if (blk_mq_hw_queue_mapped(hctx))
@@ -1442,7 +1442,7 @@ static void blk_mq_timeout_work(struct work_struct *work) container_of(work, struct request_queue, timeout_work); unsigned long next = 0; struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; /* A deadlock might occur if a request is stuck requiring a * timeout at the same time a queue freeze is waiting
@@ -2143,7 +2143,7 @@ static struct blk_mq_hw_ctx *blk_mq_get_sq_hctx(struct request_queue *q) void blk_mq_run_hw_queues(struct request_queue *q, bool async) { struct blk_mq_hw_ctx *hctx, *sq_hctx; - int i; + unsigned long i; sq_hctx = NULL; if (blk_mq_has_sqsched(q))
@@ -2171,7 +2171,7 @@ EXPORT_SYMBOL(blk_mq_run_hw_queues); void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs) { struct blk_mq_hw_ctx *hctx, *sq_hctx; - int i; + unsigned long i; sq_hctx = NULL; if (blk_mq_has_sqsched(q))
@@ -2209,7 +2209,7 @@ EXPORT_SYMBOL(blk_mq_delay_run_hw_queues); bool blk_mq_queue_stopped(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) if (blk_mq_hctx_stopped(hctx))
@@ -2248,7 +2248,7 @@ EXPORT_SYMBOL(blk_mq_stop_hw_queue); void blk_mq_stop_hw_queues(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) blk_mq_stop_hw_queue(hctx);
@@ -2266,7 +2266,7 @@ EXPORT_SYMBOL(blk_mq_start_hw_queue); void blk_mq_start_hw_queues(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) blk_mq_start_hw_queue(hctx);
@@ -2286,7 +2286,7 @@ EXPORT_SYMBOL_GPL(blk_mq_start_stopped_hw_queue); void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) blk_mq_start_stopped_hw_queue(hctx, async);
@@ -3446,7 +3446,7 @@ static void blk_mq_exit_hw_queues(struct request_queue *q, struct blk_mq_tag_set *set, int nr_queue) { struct blk_mq_hw_ctx *hctx; - unsigned int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) { if (i == nr_queue)
@@ -3637,7 +3637,8 @@ static void __blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set, static void blk_mq_map_swqueue(struct request_queue *q) { - unsigned int i, j, hctx_idx; + unsigned int j, hctx_idx; + unsigned long i; struct blk_mq_hw_ctx *hctx; struct blk_mq_ctx *ctx; struct blk_mq_tag_set *set = q->tag_set;
@@ -3744,7 +3745,7 @@ static void blk_mq_map_swqueue(struct request_queue *q) static void queue_set_hctx_shared(struct request_queue *q, bool shared) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) { if (shared) {
@@ -3844,7 +3845,7 @@ static int blk_mq_alloc_ctxs(struct request_queue *q) void blk_mq_release(struct request_queue *q) { struct blk_mq_hw_ctx *hctx, *next; - int i; + unsigned long i; queue_for_each_hw_ctx(q, hctx, i) WARN_ON_ONCE(hctx && list_empty(&hctx->hctx_list));
@@ -4362,7 +4363,8 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) { struct blk_mq_tag_set *set = q->tag_set; struct blk_mq_hw_ctx *hctx; - int i, ret; + int ret; + unsigned long i; if (!set) return -EINVAL;
@@ -4738,7 +4740,7 @@ void blk_mq_cancel_work_sync(struct request_queue *q) { if (queue_is_mq(q)) { struct blk_mq_hw_ctx *hctx; - int i; + unsigned long i; cancel_delayed_work_sync(&q->requeue_work);
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index c08971de369f..58304f978e10 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c@@ -1343,7 +1343,7 @@ static inline void rnbd_init_hw_queue(struct rnbd_clt_dev *dev, static void rnbd_init_mq_hw_queues(struct rnbd_clt_dev *dev) { - int i; + unsigned long i; struct blk_mq_hw_ctx *hctx; struct rnbd_queue *q;
--
2.31.1