user/sven/linux.git/block, branch v4.14.231

block: only update parent bi_status when bio fail

2021-04-16T09:57:53Z

[ Upstream commit 3edf5346e4f2ce2fa0c94651a90a8dda169565ee ] For multiple split bios, if one of the bio is fail, the whole should return error to application. But we found there is a race between bio_integrity_verify_fn and bio complete, which return io success to application after one of the bio fail. The race as following: split bio(READ) kworker nvme_complete_rq blk_update_request //split error=0 bio_endio bio_integrity_endio queue_work(kintegrityd_wq, &bip->bip_work); bio_integrity_verify_fn bio_endio //split bio __bio_chain_endio if (!parent->bi_status) nvme_irq blk_update_request //parent error=7 req_bio_endio bio->bi_status = 7 //parent bio parent->bi_status = 0 parent->bi_end_io() // return bi_status=0 The bio has been split as two: split and parent. When split bio completed, it depends on kworker to do endio, while bio_integrity_verify_fn have been interrupted by parent bio complete irq handler. Then, parent bio->bi_status which have been set in irq handler will overwrite by kworker. In fact, even without the above race, we also need to conside the concurrency beteen mulitple split bio complete and update the same parent bi_status. Normally, multiple split bios will be issued to the same hctx and complete from the same irq vector. But if we have updated queue map between multiple split bios, these bios may complete on different hw queue and different irq vector. Then the concurrency update parent bi_status may cause the final status error. Suggested-by: Keith Busch Signed-off-by: Yufen Yu Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20210331115359.1125679-1-yuyufen@huawei.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

blk-settings: align max_sectors on "logical_block_size" boundary

2021-03-03T17:22:50Z

commit 97f433c3601a24d3513d06f575a389a2ca4e11e4 upstream. We get I/O errors when we run md-raid1 on the top of dm-integrity on the top of ramdisk. device-mapper: integrity: Bio not aligned on 8 sectors: 0xff00, 0xff device-mapper: integrity: Bio not aligned on 8 sectors: 0xff00, 0xff device-mapper: integrity: Bio not aligned on 8 sectors: 0xffff, 0x1 device-mapper: integrity: Bio not aligned on 8 sectors: 0xffff, 0x1 device-mapper: integrity: Bio not aligned on 8 sectors: 0x8048, 0xff device-mapper: integrity: Bio not aligned on 8 sectors: 0x8147, 0xff device-mapper: integrity: Bio not aligned on 8 sectors: 0x8246, 0xff device-mapper: integrity: Bio not aligned on 8 sectors: 0x8345, 0xbb The ramdisk device has logical_block_size 512 and max_sectors 255. The dm-integrity device uses logical_block_size 4096 and it doesn't affect the "max_sectors" value - thus, it inherits 255 from the ramdisk. So, we have a device with max_sectors not aligned on logical_block_size. The md-raid device sees that the underlying leg has max_sectors 255 and it will split the bios on 255-sector boundary, making the bios unaligned on logical_block_size. In order to fix the bug, we round down max_sectors to logical_block_size. Cc: stable@vger.kernel.org Reviewed-by: Ming Lei Signed-off-by: Mikulas Patocka Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block: fix use-after-free in disk_part_iter_next

2021-01-17T12:59:01Z

commit aebf5db917055b38f4945ed6d621d9f07a44ff30 upstream. Make sure that bdgrab() is done on the 'block_device' instance before referring to it for avoiding use-after-free. Cc: Reported-by: syzbot+825f0f9657d4e528046e@syzkaller.appspotmail.com Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

blk-cgroup: Pre-allocate tree node on blkg_conf_prep

2020-11-10T09:29:05Z

[ Upstream commit f255c19b3ab46d3cad3b1b2e1036f4c926cb1d0c ] Similarly to commit 457e490f2b741 ("blkcg: allocate struct blkcg_gq outside request queue spinlock"), blkg_create can also trigger occasional -ENOMEM failures at the radix insertion because any allocation inside blkg_create has to be non-blocking, making it more likely to fail. This causes trouble for userspace tools trying to configure io weights who need to deal with this condition. This patch reduces the occurrence of -ENOMEMs on this path by preloading the radix tree element on a GFP_KERNEL context, such that we guarantee the later non-blocking insertion won't fail. A similar solution exists in blkcg_init_queue for the same situation. Acked-by: Tejun Heo Signed-off-by: Gabriel Krisman Bertazi Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

blk-cgroup: Fix memleak on error path

2020-11-10T09:29:05Z

[ Upstream commit 52abfcbd57eefdd54737fc8c2dc79d8f46d4a3e5 ] If new_blkg allocation raced with blk_policy change and blkg_lookup_check fails, new_blkg is leaked. Acked-by: Tejun Heo Signed-off-by: Gabriel Krisman Bertazi Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: ensure bdi->io_pages is always initialized

2020-09-12T11:39:11Z

[ Upstream commit de1b0ee490eafdf65fac9eef9925391a8369f2dc ] If a driver leaves the limit settings as the defaults, then we don't initialize bdi->io_pages. This means that file systems may need to work around bdi->io_pages == 0, which is somewhat messy. Initialize the default value just like we do for ->ra_pages. Cc: stable@vger.kernel.org Fixes: 9491ae4aade6 ("mm: don't cap request size based on read-ahead setting") Reported-by: OGAWA Hirofumi Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block/bio-integrity: don't free 'buf' if bio_integrity_add_page() failed

2020-06-30T19:37:57Z

commit a75ca9303175d36af93c0937dd9b1a6422908b8d upstream. commit e7bf90e5afe3 ("block/bio-integrity: fix a memory leak bug") added a kfree() for 'buf' if bio_integrity_add_page() returns '0'. However, the object will be freed in bio_integrity_free() since 'bio->bi_opf' and 'bio->bi_integrity' were set previousy in bio_integrity_alloc(). Fixes: commit e7bf90e5afe3 ("block/bio-integrity: fix a memory leak bug") Signed-off-by: yu kuai Reviewed-by: Ming Lei Reviewed-by: Bob Liu Acked-by: Martin K. Petersen Signed-off-by: Jens Axboe Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

blk-mq: move _blk_mq_update_nr_hw_queues synchronize_rcu call

2020-06-20T08:25:17Z

This fixes the 4.14 backport commit 574eb136ec7f315c3ef2ca68fa9b3e16c56baa24 which was upstream commit f5bbbbe4d63577026f908a809f22f5fd5a90ea1f. The upstream commit added a call to synchronize_rcu to _blk_mq_update_nr_hw_queues, just after freezing queues. In the backport this landed just after unfreezeing queues. This commit moves the call to its intended place. Fixes: 574eb136ec7f ("blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter") Signed-off-by: Giuliano Procida Signed-off-by: Sasha Levin

block, bfq: fix use-after-free in bfq_idle_slice_timer_body

2020-04-24T06:00:30Z

[ Upstream commit 2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9 ] In bfq_idle_slice_timer func, bfqq = bfqd->in_service_queue is not in bfqd-lock critical section. The bfqq, which is not equal to NULL in bfq_idle_slice_timer, may be freed after passing to bfq_idle_slice_timer_body. So we will access the freed memory. In addition, considering the bfqq may be in race, we should firstly check whether bfqq is in service before doing something on it in bfq_idle_slice_timer_body func. If the bfqq in race is not in service, it means the bfqq has been expired through __bfq_bfqq_expire func, and wait_request flags has been cleared in __bfq_bfqd_reset_in_service func. So we do not need to re-clear the wait_request of bfqq which is not in service. KASAN log is given as follows: [13058.354613] ================================================================== [13058.354640] BUG: KASAN: use-after-free in bfq_idle_slice_timer+0xac/0x290 [13058.354644] Read of size 8 at addr ffffa02cf3e63f78 by task fork13/19767 [13058.354646] [13058.354655] CPU: 96 PID: 19767 Comm: fork13 [13058.354661] Call trace: [13058.354667] dump_backtrace+0x0/0x310 [13058.354672] show_stack+0x28/0x38 [13058.354681] dump_stack+0xd8/0x108 [13058.354687] print_address_description+0x68/0x2d0 [13058.354690] kasan_report+0x124/0x2e0 [13058.354697] __asan_load8+0x88/0xb0 [13058.354702] bfq_idle_slice_timer+0xac/0x290 [13058.354707] __hrtimer_run_queues+0x298/0x8b8 [13058.354710] hrtimer_interrupt+0x1b8/0x678 [13058.354716] arch_timer_handler_phys+0x4c/0x78 [13058.354722] handle_percpu_devid_irq+0xf0/0x558 [13058.354731] generic_handle_irq+0x50/0x70 [13058.354735] __handle_domain_irq+0x94/0x110 [13058.354739] gic_handle_irq+0x8c/0x1b0 [13058.354742] el1_irq+0xb8/0x140 [13058.354748] do_wp_page+0x260/0xe28 [13058.354752] __handle_mm_fault+0x8ec/0x9b0 [13058.354756] handle_mm_fault+0x280/0x460 [13058.354762] do_page_fault+0x3ec/0x890 [13058.354765] do_mem_abort+0xc0/0x1b0 [13058.354768] el0_da+0x24/0x28 [13058.354770] [13058.354773] Allocated by task 19731: [13058.354780] kasan_kmalloc+0xe0/0x190 [13058.354784] kasan_slab_alloc+0x14/0x20 [13058.354788] kmem_cache_alloc_node+0x130/0x440 [13058.354793] bfq_get_queue+0x138/0x858 [13058.354797] bfq_get_bfqq_handle_split+0xd4/0x328 [13058.354801] bfq_init_rq+0x1f4/0x1180 [13058.354806] bfq_insert_requests+0x264/0x1c98 [13058.354811] blk_mq_sched_insert_requests+0x1c4/0x488 [13058.354818] blk_mq_flush_plug_list+0x2d4/0x6e0 [13058.354826] blk_flush_plug_list+0x230/0x548 [13058.354830] blk_finish_plug+0x60/0x80 [13058.354838] read_pages+0xec/0x2c0 [13058.354842] __do_page_cache_readahead+0x374/0x438 [13058.354846] ondemand_readahead+0x24c/0x6b0 [13058.354851] page_cache_sync_readahead+0x17c/0x2f8 [13058.354858] generic_file_buffered_read+0x588/0xc58 [13058.354862] generic_file_read_iter+0x1b4/0x278 [13058.354965] ext4_file_read_iter+0xa8/0x1d8 [ext4] [13058.354972] __vfs_read+0x238/0x320 [13058.354976] vfs_read+0xbc/0x1c0 [13058.354980] ksys_read+0xdc/0x1b8 [13058.354984] __arm64_sys_read+0x50/0x60 [13058.354990] el0_svc_common+0xb4/0x1d8 [13058.354994] el0_svc_handler+0x50/0xa8 [13058.354998] el0_svc+0x8/0xc [13058.354999] [13058.355001] Freed by task 19731: [13058.355007] __kasan_slab_free+0x120/0x228 [13058.355010] kasan_slab_free+0x10/0x18 [13058.355014] kmem_cache_free+0x288/0x3f0 [13058.355018] bfq_put_queue+0x134/0x208 [13058.355022] bfq_exit_icq_bfqq+0x164/0x348 [13058.355026] bfq_exit_icq+0x28/0x40 [13058.355030] ioc_exit_icq+0xa0/0x150 [13058.355035] put_io_context_active+0x250/0x438 [13058.355038] exit_io_context+0xd0/0x138 [13058.355045] do_exit+0x734/0xc58 [13058.355050] do_group_exit+0x78/0x220 [13058.355054] __wake_up_parent+0x0/0x50 [13058.355058] el0_svc_common+0xb4/0x1d8 [13058.355062] el0_svc_handler+0x50/0xa8 [13058.355066] el0_svc+0x8/0xc [13058.355067] [13058.355071] The buggy address belongs to the object at ffffa02cf3e63e70#012 which belongs to the cache bfq_queue of size 464 [13058.355075] The buggy address is located 264 bytes inside of#012 464-byte region [ffffa02cf3e63e70, ffffa02cf3e64040) [13058.355077] The buggy address belongs to the page: [13058.355083] page:ffff7e80b3cf9800 count:1 mapcount:0 mapping:ffff802db5c90780 index:0xffffa02cf3e606f0 compound_mapcount: 0 [13058.366175] flags: 0x2ffffe0000008100(slab|head) [13058.370781] raw: 2ffffe0000008100 ffff7e80b53b1408 ffffa02d730c1c90 ffff802db5c90780 [13058.370787] raw: ffffa02cf3e606f0 0000000000370023 00000001ffffffff 0000000000000000 [13058.370789] page dumped because: kasan: bad access detected [13058.370791] [13058.370792] Memory state around the buggy address: [13058.370797] ffffa02cf3e63e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fb fb [13058.370801] ffffa02cf3e63e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [13058.370805] >ffffa02cf3e63f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [13058.370808] ^ [13058.370811] ffffa02cf3e63f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [13058.370815] ffffa02cf3e64000: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [13058.370817] ================================================================== [13058.370820] Disabling lock debugging due to kernel taint Here, we directly pass the bfqd to bfq_idle_slice_timer_body func. -- V2->V3: rewrite the comment as suggested by Paolo Valente V1->V2: add one comment, and add Fixes and Reported-by tag. Fixes: aee69d78d ("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler") Acked-by: Paolo Valente Reported-by: Wang Wang Signed-off-by: Zhiqiang Liu Signed-off-by: Feilong Lin Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: Fix use-after-free issue accessing struct io_cq

2020-04-24T06:00:28Z

[ Upstream commit 30a2da7b7e225ef6c87a660419ea04d3cef3f6a7 ] There is a potential race between ioc_release_fn() and ioc_clear_queue() as shown below, due to which below kernel crash is observed. It also can result into use-after-free issue. context#1: context#2: ioc_release_fn() __ioc_clear_queue() gets the same icq ->spin_lock(&ioc->lock); ->spin_lock(&ioc->lock); ->ioc_destroy_icq(icq); ->list_del_init(&icq->q_node); ->call_rcu(&icq->__rcu_head, icq_free_icq_rcu); ->spin_unlock(&ioc->lock); ->ioc_destroy_icq(icq); ->hlist_del_init(&icq->ioc_node); This results into below crash as this memory is now used by icq->__rcu_head in context#1. There is a chance that icq could be free'd as well. 22150.386550: <6> Unable to handle kernel write to read-only memory at virtual address ffffffaa8d31ca50 ... Call trace: 22150.607350: <2> ioc_destroy_icq+0x44/0x110 22150.611202: <2> ioc_clear_queue+0xac/0x148 22150.615056: <2> blk_cleanup_queue+0x11c/0x1a0 22150.619174: <2> __scsi_remove_device+0xdc/0x128 22150.623465: <2> scsi_forget_host+0x2c/0x78 22150.627315: <2> scsi_remove_host+0x7c/0x2a0 22150.631257: <2> usb_stor_disconnect+0x74/0xc8 22150.635371: <2> usb_unbind_interface+0xc8/0x278 22150.639665: <2> device_release_driver_internal+0x198/0x250 22150.644897: <2> device_release_driver+0x24/0x30 22150.649176: <2> bus_remove_device+0xec/0x140 22150.653204: <2> device_del+0x270/0x460 22150.656712: <2> usb_disable_device+0x120/0x390 22150.660918: <2> usb_disconnect+0xf4/0x2e0 22150.664684: <2> hub_event+0xd70/0x17e8 22150.668197: <2> process_one_work+0x210/0x480 22150.672222: <2> worker_thread+0x32c/0x4c8 Fix this by adding a new ICQ_DESTROYED flag in ioc_destroy_icq() to indicate this icq is once marked as destroyed. Also, ensure __ioc_clear_queue() is accessing icq within rcu_read_lock/unlock so that icq doesn't get free'd up while it is still using it. Signed-off-by: Sahitya Tummala Co-developed-by: Pradeep P V K Signed-off-by: Pradeep P V K Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin