kernel.git/drivers/nvme/host/multipath.c, branch linux-5.5.y

nvme-multipath: Fix memory leak with ana_log_buf

2020-02-28T16:23:36Z

commit 3b7830904e17202524bad1974505a9bfc718d31f upstream. kmemleak reports a memory leak with the ana_log_buf allocated by nvme_mpath_init(): unreferenced object 0xffff888120e94000 (size 8208): comm "nvme", pid 6884, jiffies 4295020435 (age 78786.312s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................ 01 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000e2360188>] kmalloc_order+0x97/0xc0 [<0000000079b18dd4>] kmalloc_order_trace+0x24/0x100 [<00000000f50c0406>] __kmalloc+0x24c/0x2d0 [<00000000f31a10b9>] nvme_mpath_init+0x23c/0x2b0 [<000000005802589e>] nvme_init_identify+0x75f/0x1600 [<0000000058ef911b>] nvme_loop_configure_admin_queue+0x26d/0x280 [<00000000673774b9>] nvme_loop_create_ctrl+0x2a7/0x710 [<00000000f1c7a233>] nvmf_dev_write+0xc66/0x10b9 [<000000004199f8d0>] __vfs_write+0x50/0xa0 [<0000000065466fef>] vfs_write+0xf3/0x280 [<00000000b0db9a8b>] ksys_write+0xc6/0x160 [<0000000082156b91>] __x64_sys_write+0x43/0x50 [<00000000c34fbb6d>] do_syscall_64+0x77/0x2f0 [<00000000bbc574c9>] entry_SYSCALL_64_after_hwframe+0x49/0xbe nvme_mpath_init() is called by nvme_init_identify() which is called in multiple places (nvme_reset_work(), nvme_passthru_end(), etc). This means nvme_mpath_init() may be called multiple times before nvme_mpath_uninit() (which is only called on nvme_free_ctrl()). When nvme_mpath_init() is called multiple times, it overwrites the ana_log_buf pointer with a new allocation, thus leaking the previous allocation. To fix this, free ana_log_buf before allocating a new one. Fixes: 0d0b660f214dc490 ("nvme: add ANA support") Cc: Reviewed-by: Sagi Grimberg Reviewed-by: Christoph Hellwig Signed-off-by: Logan Gunthorpe Signed-off-by: Keith Busch Signed-off-by: Greg Kroah-Hartman

Merge tag 'for-5.5/drivers-20191121' of git://git.kernel.dk/linux-block

2019-11-25T19:15:41Z

Pull block driver updates from Jens Axboe: "Here are the main block driver updates for 5.5. Nothing major in here, mostly just fixes. This contains: - a set of bcache changes via Coly - MD changes from Song - loop unmap write-zeroes fix (Darrick) - spelling fixes (Geert) - zoned additions cleanups to null_blk/dm (Ajay) - allow null_blk online submit queue changes (Bart) - NVMe changes via Keith, nothing major here either" * tag 'for-5.5/drivers-20191121' of git://git.kernel.dk/linux-block: (56 commits) Revert "bcache: fix fifo index swapping condition in journal_pin_cmp()" drivers/md/raid5-ppl.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET drivers/md/raid5.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET bcache: don't export symbols bcache: remove the extra cflags for request.o bcache: at least try to shrink 1 node in bch_mca_scan() bcache: add idle_max_writeback_rate sysfs interface bcache: add code comments in bch_btree_leaf_dirty() bcache: fix deadlock in bcache_allocator bcache: add code comment bch_keylist_pop() and bch_keylist_pop_front() bcache: deleted code comments for dead code in bch_data_insert_keys() bcache: add more accurate error messages in read_super() bcache: fix static checker warning in bcache_device_free() bcache: fix a lost wake-up problem caused by mca_cannibalize_lock bcache: fix fifo index swapping condition in journal_pin_cmp() md/raid10: prevent access of uninitialized resync_pages offset md: avoid invalid memory access for array sb->dev_roles md/raid1: avoid soft lockup under high load null_blk: add zone open, close, and finish support dm: add zone open, close and finish support ...

nvme-multipath: fix crash in nvme_mpath_clear_ctrl_paths

2019-11-05T15:30:37Z

nvme_mpath_clear_ctrl_paths() iterates through the ctrl->namespaces list while holding ctrl->scan_lock. This does not seem to be the correct way of protecting from concurrent list modification. Specifically, nvme_scan_work() sorts ctrl->namespaces AFTER unlocking scan_lock. This may result in the following (rare) crash in ctrl disconnect during scan_work: BUG: kernel NULL pointer dereference, address: 0000000000000050 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 3995 Comm: nvme 5.3.5-050305-generic RIP: 0010:nvme_mpath_clear_current_path+0xe/0x90 [nvme_core] ... Call Trace: nvme_mpath_clear_ctrl_paths+0x3c/0x70 [nvme_core] nvme_remove_namespaces+0x35/0xe0 [nvme_core] nvme_do_delete_ctrl+0x47/0x90 [nvme_core] nvme_sysfs_delete+0x49/0x60 [nvme_core] dev_attr_store+0x17/0x30 sysfs_kf_write+0x3e/0x50 kernfs_fop_write+0x11e/0x1a0 __vfs_write+0x1b/0x40 vfs_write+0xb9/0x1a0 ksys_write+0x67/0xe0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x5a/0x130 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f8d02bfb154 Fix: After taking scan_lock in nvme_mpath_clear_ctrl_paths() down_read(&ctrl->namespaces_rwsem) as well to make list traversal safe. This will not cause deadlocks because taking scan_lock never happens while holding the namespaces_rwsem. Moreover, scan work downs namespaces_rwsem in the same order. Alternative: sort ctrl->namespaces in nvme_scan_work() while still holding the scan_lock. This would leave nvme_mpath_clear_ctrl_paths() without correct protection against ctrl->namespaces modification by anyone other than scan_work. Reviewed-by: Sagi Grimberg Reviewed-by: Christoph Hellwig Signed-off-by: Anton Eidelman Signed-off-by: Keith Busch

nvme: Fix parsing of ANA log page

2019-11-04T17:56:42Z

Check validity of offset into ANA log buffer before accessing nvme_ana_group_desc. This check ensures the size of ANA log buffer >= offset + sizeof(nvme_ana_group_desc) Reviewed-by: Sagi Grimberg Signed-off-by: Prabhath Sajeepa Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

nvme: introduce "Command Aborted By host" status code

2019-11-04T17:56:41Z

Fix the status code of canceled requests initiated by the host according to TP4028 (Status Code 0x371): "Command Aborted By host: The command was aborted as a result of host action (e.g., the host disconnected the Fabric connection)." Also in a multipath environment, unless otherwise specified, errors of this type (path related) should be retried using a different path, if one is available. Signed-off-by: Max Gurtovoy Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

nvme-multipath: remove unused groups_only mode in ana log

2019-10-29T14:55:00Z

groups_only mode in nvme_read_ana_log() is no longer used: remove it. Reviewed-by: Sagi Grimberg Signed-off-by: Anton Eidelman Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

nvme-multipath: fix possible io hang after ctrl reconnect

2019-10-29T14:55:00Z

The following scenario results in an IO hang: 1) ctrl completes a request with NVME_SC_ANA_TRANSITION. NVME_NS_ANA_PENDING bit in ns->flags is set and ana_work is triggered. 2) ana_work: nvme_read_ana_log() tries to get the ANA log page from the ctrl. This fails because ctrl disconnects. Therefore nvme_update_ns_ana_state() is not called and NVME_NS_ANA_PENDING bit in ns->flags is not cleared. 3) ctrl reconnects: nvme_mpath_init(ctrl,...) calls nvme_read_ana_log(ctrl, groups_only=true). However, nvme_update_ana_state() does not update namespaces because nr_nsids = 0 (due to groups_only mode). 4) scan_work calls nvme_validate_ns() finds the ns and re-validates OK. Result: The ctrl is now live but NVME_NS_ANA_PENDING bit in ns->flags is still set. Consequently ctrl will never be considered a viable path by __nvme_find_path(). IO will hang if ctrl is the only or the last path to the namespace. More generally, while ctrl is reconnecting, its ANA state may change. And because nvme_mpath_init() requests ANA log in groups_only mode, these changes are not propagated to the existing ctrl namespaces. This may result in a mal-function or an IO hang. Solution: nvme_mpath_init() will nvme_read_ana_log() with groups_only set to false. This will not harm the new ctrl case (no namespaces present), and will make sure the ANA state of namespaces gets updated after reconnect. Note: Another option would be for nvme_mpath_init() to invoke nvme_parse_ana_log(..., nvme_set_ns_ana_state) for each existing namespace. Reviewed-by: Sagi Grimberg Signed-off-by: Anton Eidelman Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

Merge tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-block

2019-09-17T23:57:47Z

Pull block updates from Jens Axboe: - Two NVMe pull requests: - ana log parse fix from Anton - nvme quirks support for Apple devices from Ben - fix missing bio completion tracing for multipath stack devices from Hannes and Mikhail - IP TOS settings for nvme rdma and tcp transports from Israel - rq_dma_dir cleanups from Israel - tracing for Get LBA Status command from Minwoo - Some nvme-tcp cleanups from Minwoo, Potnuri and Myself - Some consolidation between the fabrics transports for handling the CAP register - reset race with ns scanning fix for fabrics (move fabrics commands to a dedicated request queue with a different lifetime from the admin request queue)." - controller reset and namespace scan races fixes - nvme discovery log change uevent support - naming improvements from Keith - multiple discovery controllers reject fix from James - some regular cleanups from various people - Series fixing (and re-fixing) null_blk debug printing and nr_devices checks (André) - A few pull requests from Song, with fixes from Andy, Guoqing, Guilherme, Neil, Nigel, and Yufen. - REQ_OP_ZONE_RESET_ALL support (Chaitanya) - Bio merge handling unification (Christoph) - Pick default elevator correctly for devices with special needs (Damien) - Block stats fixes (Hou) - Timeout and support devices nbd fixes (Mike) - Series fixing races around elevator switching and device add/remove (Ming) - sed-opal cleanups (Revanth) - Per device weight support for BFQ (Fam) - Support for blk-iocost, a new model that can properly account cost of IO workloads. (Tejun) - blk-cgroup writeback fixes (Tejun) - paride queue init fixes (zhengbin) - blk_set_runtime_active() cleanup (Stanley) - Block segment mapping optimizations (Bart) - lightnvm fixes (Hans/Minwoo/YueHaibing) - Various little fixes and cleanups * tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-block: (186 commits) null_blk: format pr_* logs with pr_fmt null_blk: match the type of parameter nr_devices null_blk: do not fail the module load with zero devices block: also check RQF_STATS in blk_mq_need_time_stamp() block: make rq sector size accessible for block stats bfq: Fix bfq linkage error raid5: use bio_end_sector in r5_next_bio raid5: remove STRIPE_OPS_REQ_PENDING md: add feature flag MD_FEATURE_RAID0_LAYOUT md/raid0: avoid RAID0 data corruption due to layout confusion. raid5: don't set STRIPE_HANDLE to stripe which is in batch list raid5: don't increment read_errors on EILSEQ return nvmet: fix a wrong error status returned in error log page nvme: send discovery log page change events to userspace nvme: add uevent variables for controller devices nvme: enable aen regardless of the presence of I/O queues nvme-fabrics: allow discovery subsystems accept a kato nvmet: Use PTR_ERR_OR_ZERO() in nvmet_init_discovery() nvme: Remove redundant assignment of cq vector nvme: Assign subsys instance from first ctrl ...

nvme-multipath: fix ana log nsid lookup when nsid is not found

2019-08-29T19:55:02Z

ANA log parsing invokes nvme_update_ana_state() per ANA group desc. This updates the state of namespaces with nsids in desc->nsids[]. Both ctrl->namespaces list and desc->nsids[] array are sorted by nsid. Hence nvme_update_ana_state() performs a single walk over ctrl->namespaces: - if current namespace matches the current desc->nsids[n], this namespace is updated, and n is incremented. - the process stops when it encounters the end of either ctrl->namespaces end or desc->nsids[] In case desc->nsids[n] does not match any of ctrl->namespaces, the remaining nsids following desc->nsids[n] will not be updated. Such situation was considered abnormal and generated WARN_ON_ONCE. However ANA log MAY contain nsids not (yet) found in ctrl->namespaces. For example, lets consider the following scenario: - nvme0 exposes namespaces with nsids = [2, 3] to the host - a new namespace nsid = 1 is added dynamically - also, a ANA topology change is triggered - NS_CHANGED aen is generated and triggers scan_work - before scan_work discovers nsid=1 and creates a namespace, a NOTICE_ANA aen was issues and ana_work receives ANA log with nsids=[1, 2, 3] Result: ana_work fails to update ANA state on existing namespaces [2, 3] Solution: Change the way nvme_update_ana_state() namespace list walk checks the current namespace against desc->nsids[n] as follows: a) ns->head->ns_id < desc->nsids[n]: keep walking ctrl->namespaces. b) ns->head->ns_id == desc->nsids[n]: match, update the namespace c) ns->head->ns_id >= desc->nsids[n]: skip to desc->nsids[n+1] This enables correct operation in the scenario described above. This also allows ANA log to contain nsids currently invisible to the host, i.e. inactive nsids. Signed-off-by: Anton Eidelman Reviewed-by: James Smart Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Signed-off-by: Sagi Grimberg

nvme-multipath: fix possible I/O hang when paths are updated

2019-08-20T17:02:10Z

nvme_state_set_live() making a path available triggers requeue_work in order to resubmit requests that ended up on requeue_list when no paths were available. This requeue_work may race with concurrent nvme_ns_head_make_request() that do not observe the live path yet. Such concurrent requests may by made by either: - New IO submission. - Requeue_work triggered by nvme_failover_req() or another ana_work. A race may cause requeue_work capture the state of requeue_list before more requests get onto the list. These requests will stay on the list forever unless requeue_work is triggered again. In order to prevent such race, nvme_state_set_live() should synchronize_srcu(&head->srcu) before triggering the requeue_work and prevent nvme_ns_head_make_request referencing an old snapshot of the path list. Reviewed-by: Christoph Hellwig Signed-off-by: Anton Eidelman Signed-off-by: Sagi Grimberg Signed-off-by: Jens Axboe