1. 09 Jan, 2021 4 commits
    • Coly Li's avatar
      bcache: introduce BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE for large bucket · b16671e8
      Coly Li authored
      When large bucket feature was added, BCH_FEATURE_INCOMPAT_LARGE_BUCKET
      was introduced into the incompat feature set. It used bucket_size_hi
      (which was added at the tail of struct cache_sb_disk) to extend current
      16bit bucket size to 32bit with existing bucket_size in struct
      cache_sb_disk.
      
      This is not a good idea, there are two obvious problems,
      - Bucket size is always value power of 2, if store log2(bucket size) in
        existing bucket_size of struct cache_sb_disk, it is unnecessary to add
        bucket_size_hi.
      - Macro csum_set() assumes d[SB_JOURNAL_BUCKETS] is the last member in
        struct cache_sb_disk, bucket_size_hi was added after d[] which makes
        csum_set calculate an unexpected super block checksum.
      
      To fix the above problems, this patch introduces a new incompat feature
      bit BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE, when this bit is set, it
      means bucket_size in struct cache_sb_disk stores the order of power-of-2
      bucket size value. When user specifies a bucket size larger than 32768
      sectors, BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE will be set to
      incompat feature set, and bucket_size stores log2(bucket size) more
      than store the real bucket size value.
      
      The obsoleted BCH_FEATURE_INCOMPAT_LARGE_BUCKET won't be used anymore,
      it is renamed to BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET and still only
      recognized by kernel driver for legacy compatible purpose. The previous
      bucket_size_hi is renmaed to obso_bucket_size_hi in struct cache_sb_disk
      and not used in bcache-tools anymore.
      
      For cache device created with BCH_FEATURE_INCOMPAT_LARGE_BUCKET feature,
      bcache-tools and kernel driver still recognize the feature string and
      display it as "obso_large_bucket".
      
      With this change, the unnecessary extra space extend of bcache on-disk
      super block can be avoided, and csum_set() may generate expected check
      sum as well.
      
      Fixes: ffa47032 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
      Signed-off-by: default avatarColy Li <colyli@suse.de>
      Cc: stable@vger.kernel.org # 5.9+
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      b16671e8
    • Coly Li's avatar
      bcache: check unsupported feature sets for bcache register · 1dfc0686
      Coly Li authored
      This patch adds the check for features which is incompatible for
      current supported feature sets.
      
      Now if the bcache device created by bcache-tools has features that
      current kernel doesn't support, read_super() will fail with error
      messoage. E.g. if an unsupported incompatible feature detected,
      bcache register will fail with dmesg "bcache: register_bcache() error :
      Unsupported incompatible feature found".
      
      Fixes: d721a43f ("bcache: increase super block version for cache device and backing device")
      Fixes: ffa47032 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
      Signed-off-by: default avatarColy Li <colyli@suse.de>
      Cc: stable@vger.kernel.org # 5.9+
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      1dfc0686
    • Coly Li's avatar
      bcache: fix typo from SUUP to SUPP in features.h · f7b4943d
      Coly Li authored
      This patch fixes the following typos,
      from BCH_FEATURE_COMPAT_SUUP to BCH_FEATURE_COMPAT_SUPP
      from BCH_FEATURE_INCOMPAT_SUUP to BCH_FEATURE_INCOMPAT_SUPP
      from BCH_FEATURE_INCOMPAT_SUUP to BCH_FEATURE_RO_COMPAT_SUPP
      
      Fixes: d721a43f ("bcache: increase super block version for cache device and backing device")
      Fixes: ffa47032 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
      Signed-off-by: default avatarColy Li <colyli@suse.de>
      Cc: stable@vger.kernel.org # 5.9+
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      f7b4943d
    • Yi Li's avatar
      bcache: set pdev_set_uuid before scond loop iteration · e8092707
      Yi Li authored
      There is no need to reassign pdev_set_uuid in the second loop iteration,
      so move it to the place before second loop.
      Signed-off-by: default avatarYi Li <yili@winhong.com>
      Signed-off-by: default avatarColy Li <colyli@suse.de>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      e8092707
  2. 08 Jan, 2021 7 commits
    • John Garry's avatar
      blk-mq-debugfs: Add decode for BLK_MQ_F_TAG_HCTX_SHARED · 02f938e9
      John Garry authored
      Showing the hctx flags for when BLK_MQ_F_TAG_HCTX_SHARED is set gives
      something like:
      
      root@debian:/home/john# more /sys/kernel/debug/block/sda/hctx0/flags
      alloc_policy=FIFO SHOULD_MERGE|TAG_QUEUE_SHARED|3
      
      Add the decoding for that flag.
      
      Fixes: 32bc15af ("blk-mq: Facilitate a shared sbitmap per tagset")
      Signed-off-by: default avatarJohn Garry <john.garry@huawei.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      02f938e9
    • Jack Wang's avatar
      block/rnbd-clt: avoid module unload race with close confirmation · 3a21777c
      Jack Wang authored
      We had kernel panic, it is caused by unload module and last
      close confirmation.
      
      call trace:
      [1196029.743127]  free_sess+0x15/0x50 [rtrs_client]
      [1196029.743128]  rtrs_clt_close+0x4c/0x70 [rtrs_client]
      [1196029.743129]  ? rnbd_clt_unmap_device+0x1b0/0x1b0 [rnbd_client]
      [1196029.743130]  close_rtrs+0x25/0x50 [rnbd_client]
      [1196029.743131]  rnbd_client_exit+0x93/0xb99 [rnbd_client]
      [1196029.743132]  __x64_sys_delete_module+0x190/0x260
      
      And in the crashdump confirmation kworker is also running.
      PID: 6943   TASK: ffff9e2ac8098000  CPU: 4   COMMAND: "kworker/4:2"
       #0 [ffffb206cf337c30] __schedule at ffffffff9f93f891
       #1 [ffffb206cf337cc8] schedule at ffffffff9f93fe98
       #2 [ffffb206cf337cd0] schedule_timeout at ffffffff9f943938
       #3 [ffffb206cf337d50] wait_for_completion at ffffffff9f9410a7
       #4 [ffffb206cf337da0] __flush_work at ffffffff9f08ce0e
       #5 [ffffb206cf337e20] rtrs_clt_close_conns at ffffffffc0d5f668 [rtrs_client]
       #6 [ffffb206cf337e48] rtrs_clt_close at ffffffffc0d5f801 [rtrs_client]
       #7 [ffffb206cf337e68] close_rtrs at ffffffffc0d26255 [rnbd_client]
       #8 [ffffb206cf337e78] free_sess at ffffffffc0d262ad [rnbd_client]
       #9 [ffffb206cf337e88] rnbd_clt_put_dev at ffffffffc0d266a7 [rnbd_client]
      
      The problem is both code path try to close same session, which lead to
      panic.
      
      To fix it, just skip the sess if the refcount already drop to 0.
      
      Fixes: f7a7a5c2 ("block/rnbd: client: main functionality")
      Signed-off-by: default avatarJack Wang <jinpu.wang@cloud.ionos.com>
      Reviewed-by: default avatarGioh Kim <gi-oh.kim@cloud.ionos.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      3a21777c
    • Swapnil Ingle's avatar
      block/rnbd: Adding name to the Contributors List · ef8048dd
      Swapnil Ingle authored
      Adding name to the Contributors List
      Signed-off-by: default avatarSwapnil Ingle <ingleswapnil@gmail.com>
      Acked-by: default avatarJack Wang <jinpu.wang@cloud.ionos.com>
      Acked-by: default avatarDanil Kipnis <danil.kipnis@cloud.ionos.com>
      Signed-off-by: default avatarJack Wang <jinpu.wang@cloud.ionos.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      ef8048dd
    • Guoqing Jiang's avatar
      block/rnbd-clt: Fix sg table use after free · 80f99093
      Guoqing Jiang authored
      Since dynamically allocate sglist is used for rnbd_iu, we can't free sg
      table after send_usr_msg since the callback function (cqe.done) could
      still access the sglist.
      
      Otherwise KASAN reports UAF issue:
      
      [ 4856.600257] BUG: KASAN: use-after-free in dma_direct_unmap_sg+0x53/0x290
      [ 4856.600772] Read of size 4 at addr ffff888206af3a98 by task swapper/1/0
      
      [ 4856.601729] CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: G        W         5.10.0-pserver #5.10.0-1+feature+linux+next+20201214.1025+0910d71
      [ 4856.601748] Hardware name: Supermicro Super Server/X11DDW-L, BIOS 3.3 02/21/2020
      [ 4856.601766] Call Trace:
      [ 4856.601785]  <IRQ>
      [ 4856.601822]  dump_stack+0x99/0xcb
      [ 4856.601856]  ? dma_direct_unmap_sg+0x53/0x290
      [ 4856.601888]  print_address_description.constprop.7+0x1e/0x230
      [ 4856.601913]  ? freeze_kernel_threads+0x73/0x73
      [ 4856.601965]  ? mark_held_locks+0x29/0xa0
      [ 4856.602019]  ? dma_direct_unmap_sg+0x53/0x290
      [ 4856.602039]  ? dma_direct_unmap_sg+0x53/0x290
      [ 4856.602079]  kasan_report.cold.9+0x37/0x7c
      [ 4856.602188]  ? mlx5_ib_post_recv+0x430/0x520 [mlx5_ib]
      [ 4856.602209]  ? dma_direct_unmap_sg+0x53/0x290
      [ 4856.602256]  dma_direct_unmap_sg+0x53/0x290
      [ 4856.602366]  complete_rdma_req+0x188/0x4b0 [rtrs_client]
      [ 4856.602451]  ? rtrs_clt_close+0x80/0x80 [rtrs_client]
      [ 4856.602535]  ? mlx5_ib_poll_cq+0x48b/0x16e0 [mlx5_ib]
      [ 4856.602589]  ? radix_tree_insert+0x3a0/0x3a0
      [ 4856.602610]  ? do_raw_spin_lock+0x119/0x1d0
      [ 4856.602647]  ? rwlock_bug.part.1+0x60/0x60
      [ 4856.602740]  rtrs_clt_rdma_done+0x3f7/0x670 [rtrs_client]
      [ 4856.602804]  ? rtrs_clt_rdma_cm_handler+0xda0/0xda0 [rtrs_client]
      [ 4856.602857]  ? check_flags.part.31+0x6c/0x1f0
      [ 4856.602927]  ? rcu_read_lock_sched_held+0xaf/0xe0
      [ 4856.602963]  ? rcu_read_lock_bh_held+0xc0/0xc0
      [ 4856.603137]  __ib_process_cq+0x10a/0x350 [ib_core]
      [ 4856.603309]  ib_poll_handler+0x41/0x1c0 [ib_core]
      [ 4856.603358]  irq_poll_softirq+0xe6/0x280
      [ 4856.603392]  ? lockdep_hardirqs_on_prepare+0x111/0x210
      [ 4856.603446]  __do_softirq+0x10d/0x646
      [ 4856.603540]  asm_call_irq_on_stack+0x12/0x20
      [ 4856.603563]  </IRQ>
      
      [ 4856.605096] Allocated by task 8914:
      [ 4856.605510]  kasan_save_stack+0x19/0x40
      [ 4856.605532]  __kasan_kmalloc.constprop.7+0xc1/0xd0
      [ 4856.605552]  __kmalloc+0x155/0x320
      [ 4856.605574]  __sg_alloc_table+0x155/0x1c0
      [ 4856.605594]  sg_alloc_table+0x1f/0x50
      [ 4856.605620]  send_msg_sess_info+0x119/0x2e0 [rnbd_client]
      [ 4856.605646]  remap_devs+0x71/0x210 [rnbd_client]
      [ 4856.605676]  init_sess+0xad8/0xe10 [rtrs_client]
      [ 4856.605706]  rtrs_clt_reconnect_work+0xd6/0x170 [rtrs_client]
      [ 4856.605728]  process_one_work+0x521/0xa90
      [ 4856.605748]  worker_thread+0x65/0x5b0
      [ 4856.605769]  kthread+0x1f2/0x210
      [ 4856.605789]  ret_from_fork+0x22/0x30
      
      [ 4856.606159] Freed by task 8914:
      [ 4856.606559]  kasan_save_stack+0x19/0x40
      [ 4856.606580]  kasan_set_track+0x1c/0x30
      [ 4856.606601]  kasan_set_free_info+0x1b/0x30
      [ 4856.606622]  __kasan_slab_free+0x108/0x150
      [ 4856.606642]  slab_free_freelist_hook+0x64/0x190
      [ 4856.606661]  kfree+0xe2/0x650
      [ 4856.606681]  __sg_free_table+0xa4/0x100
      [ 4856.606707]  send_msg_sess_info+0x1d6/0x2e0 [rnbd_client]
      [ 4856.606733]  remap_devs+0x71/0x210 [rnbd_client]
      [ 4856.606763]  init_sess+0xad8/0xe10 [rtrs_client]
      [ 4856.606792]  rtrs_clt_reconnect_work+0xd6/0x170 [rtrs_client]
      [ 4856.606813]  process_one_work+0x521/0xa90
      [ 4856.606833]  worker_thread+0x65/0x5b0
      [ 4856.606853]  kthread+0x1f2/0x210
      [ 4856.606872]  ret_from_fork+0x22/0x30
      
      The solution is to free iu's sgtable after the iu is not used anymore.
      And also move sg_alloc_table into rnbd_get_iu accordingly.
      
      Fixes: 5a1328d0 ("block/rnbd-clt: Dynamically allocate sglist for rnbd_iu")
      Signed-off-by: default avatarGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
      Signed-off-by: default avatarJack Wang <jinpu.wang@cloud.ionos.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      80f99093
    • Jack Wang's avatar
      block/rnbd-srv: Fix use after free in rnbd_srv_sess_dev_force_close · 1a84e7c6
      Jack Wang authored
      KASAN detect following BUG:
      [  778.215311] ==================================================================
      [  778.216696] BUG: KASAN: use-after-free in rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
      [  778.219037] Read of size 8 at addr ffff88b1d6516c28 by task tee/8842
      
      [  778.220500] CPU: 37 PID: 8842 Comm: tee Kdump: loaded Not tainted 5.10.0-pserver #5.10.0-1+feature+linux+next+20201214.1025+0910d71
      [  778.220529] Hardware name: Supermicro Super Server/X11DDW-L, BIOS 3.3 02/21/2020
      [  778.220555] Call Trace:
      [  778.220609]  dump_stack+0x99/0xcb
      [  778.220667]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
      [  778.220715]  print_address_description.constprop.7+0x1e/0x230
      [  778.220750]  ? freeze_kernel_threads+0x73/0x73
      [  778.220896]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
      [  778.220932]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
      [  778.220994]  kasan_report.cold.9+0x37/0x7c
      [  778.221066]  ? kobject_put+0x80/0x270
      [  778.221102]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
      [  778.221184]  rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
      [  778.221240]  rnbd_srv_dev_session_force_close_store+0x6a/0xc0 [rnbd_server]
      [  778.221304]  ? sysfs_file_ops+0x90/0x90
      [  778.221353]  kernfs_fop_write+0x141/0x240
      [  778.221451]  vfs_write+0x142/0x4d0
      [  778.221553]  ksys_write+0xc0/0x160
      [  778.221602]  ? __ia32_sys_read+0x50/0x50
      [  778.221684]  ? lockdep_hardirqs_on_prepare+0x13d/0x210
      [  778.221718]  ? syscall_enter_from_user_mode+0x1c/0x50
      [  778.221821]  do_syscall_64+0x33/0x40
      [  778.221862]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
      [  778.221896] RIP: 0033:0x7f4affdd9504
      [  778.221928] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 48 8d 05 f9 61 0d 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 49 89 d4 55 48 89 f5 53
      [  778.221956] RSP: 002b:00007fffebb36b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
      [  778.222011] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f4affdd9504
      [  778.222038] RDX: 0000000000000002 RSI: 00007fffebb36c50 RDI: 0000000000000003
      [  778.222066] RBP: 00007fffebb36c50 R08: 0000556a151aa600 R09: 00007f4affeb1540
      [  778.222094] R10: fffffffffffffc19 R11: 0000000000000246 R12: 0000556a151aa520
      [  778.222121] R13: 0000000000000002 R14: 00007f4affea6760 R15: 0000000000000002
      
      [  778.222764] Allocated by task 3212:
      [  778.223285]  kasan_save_stack+0x19/0x40
      [  778.223316]  __kasan_kmalloc.constprop.7+0xc1/0xd0
      [  778.223347]  kmem_cache_alloc_trace+0x186/0x350
      [  778.223382]  rnbd_srv_rdma_ev+0xf16/0x1690 [rnbd_server]
      [  778.223422]  process_io_req+0x4d1/0x670 [rtrs_server]
      [  778.223573]  __ib_process_cq+0x10a/0x350 [ib_core]
      [  778.223709]  ib_cq_poll_work+0x31/0xb0 [ib_core]
      [  778.223743]  process_one_work+0x521/0xa90
      [  778.223773]  worker_thread+0x65/0x5b0
      [  778.223802]  kthread+0x1f2/0x210
      [  778.223833]  ret_from_fork+0x22/0x30
      
      [  778.224296] Freed by task 8842:
      [  778.224800]  kasan_save_stack+0x19/0x40
      [  778.224829]  kasan_set_track+0x1c/0x30
      [  778.224860]  kasan_set_free_info+0x1b/0x30
      [  778.224889]  __kasan_slab_free+0x108/0x150
      [  778.224919]  slab_free_freelist_hook+0x64/0x190
      [  778.224947]  kfree+0xe2/0x650
      [  778.224982]  rnbd_destroy_sess_dev+0x2fa/0x3b0 [rnbd_server]
      [  778.225011]  kobject_put+0xda/0x270
      [  778.225046]  rnbd_srv_sess_dev_force_close+0x30/0x60 [rnbd_server]
      [  778.225081]  rnbd_srv_dev_session_force_close_store+0x6a/0xc0 [rnbd_server]
      [  778.225111]  kernfs_fop_write+0x141/0x240
      [  778.225140]  vfs_write+0x142/0x4d0
      [  778.225169]  ksys_write+0xc0/0x160
      [  778.225198]  do_syscall_64+0x33/0x40
      [  778.225227]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
      
      [  778.226506] The buggy address belongs to the object at ffff88b1d6516c00
                      which belongs to the cache kmalloc-512 of size 512
      [  778.227464] The buggy address is located 40 bytes inside of
                      512-byte region [ffff88b1d6516c00, ffff88b1d6516e00)
      
      The problem is in the sess_dev release function we call
      rnbd_destroy_sess_dev, and could free the sess_dev already, but we still
      set the keep_id in rnbd_srv_sess_dev_force_close, which lead to use
      after free.
      
      To fix it, move the keep_id before the sysfs removal, and cache the
      rnbd_srv_session for lock accessing,
      
      Fixes: 78699805 ("block/rnbd-srv: close a mapped device from server side.")
      Signed-off-by: default avatarJack Wang <jinpu.wang@cloud.ionos.com>
      Reviewed-by: default avatarGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      1a84e7c6
    • Jack Wang's avatar
      block/rnbd: Select SG_POOL for RNBD_CLIENT · 74acfa99
      Jack Wang authored
      lkp reboot following build error:
       drivers/block/rnbd/rnbd-clt.c: In function 'rnbd_softirq_done_fn':
      >> drivers/block/rnbd/rnbd-clt.c:387:2: error: implicit declaration of function 'sg_free_table_chained' [-Werror=implicit-function-declaration]
           387 |  sg_free_table_chained(&iu->sgt, RNBD_INLINE_SG_CNT);
               |  ^~~~~~~~~~~~~~~~~~~~~
      
      The reason is CONFIG_SG_POOL is not enabled in the config, to
      avoid such failure, select SG_POOL in Kconfig for RNBD_CLIENT.
      
      Fixes: 5a1328d0 ("block/rnbd-clt: Dynamically allocate sglist for rnbd_iu")
      Reported-by: default avatarkernel test robot <lkp@intel.com>
      Signed-off-by: default avatarJack Wang <jinpu.wang@cloud.ionos.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      74acfa99
    • Christoph Hellwig's avatar
      block: pre-initialize struct block_device in bdev_alloc_inode · 2d2f6f1b
      Christoph Hellwig authored
      bdev_evict_inode and bdev_free_inode are also called for the root inode
      of bdevfs, for which bdev_alloc is never called.  Move the zeroing o
      f struct block_device and the initialization of the bd_bdi field into
      bdev_alloc_inode to make sure they are initialized for the root inode
      as well.
      
      Fixes: e6cb5382 ("block: initialize struct block_device in bdev_alloc")
      Reported-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
      Tested-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      2d2f6f1b
  3. 07 Jan, 2021 2 commits
    • Jens Axboe's avatar
      Merge tag 'nvme-5.11-2021-01-07' of git://git.infradead.org/nvme into block-5.11 · 04b1ecb6
      Jens Axboe authored
      Pull NVMe updates from Christoph:
      
      "nvme updates for 5.11:
      
       - fix a race in the nvme-tcp send code (Sagi Grimberg)
       - fix a list corruption in an nvme-rdma error path (Israel Rukshin)
       - avoid a possible double fetch in nvme-pci (Lalithambika Krishnakumar)
       - add the susystem NQN quirk for a Samsung driver (Gopal Tiwari)
       - fix two compiler warnings in nvme-fcloop (James Smart)
       - don't call sleeping functions from irq context in nvme-fc (James Smart)
       - remove an unused argument (Max Gurtovoy)
       - remove unused exports (Minwoo Im)"
      
      * tag 'nvme-5.11-2021-01-07' of git://git.infradead.org/nvme:
        nvme: remove the unused status argument from nvme_trace_bio_complete
        nvmet-rdma: Fix list_del corruption on queue establishment failure
        nvme: unexport functions with no external caller
        nvme: avoid possible double fetch in handling CQE
        nvme-tcp: Fix possible race of io_work and direct send
        nvme-pci: mark Samsung PM1725a as IGNORE_DEV_SUBNQN
        nvme-fcloop: Fix sscanf type and list_first_entry_or_null warnings
        nvme-fc: avoid calling _nvme_fc_abort_outstanding_ios from interrupt context
      04b1ecb6
    • Satya Tangirala's avatar
      fs: Fix freeze_bdev()/thaw_bdev() accounting of bd_fsfreeze_sb · 04a6a536
      Satya Tangirala authored
      freeze/thaw_bdev() currently use bdev->bd_fsfreeze_count to infer
      whether or not bdev->bd_fsfreeze_sb is valid (it's valid iff
      bd_fsfreeze_count is non-zero). thaw_bdev() doesn't nullify
      bd_fsfreeze_sb.
      
      But this means a freeze_bdev() call followed by a thaw_bdev() call can
      leave bd_fsfreeze_sb with a non-null value, while bd_fsfreeze_count is
      zero. If freeze_bdev() is called again, and this time
      get_active_super() returns NULL (e.g. because the FS is unmounted),
      we'll end up with bd_fsfreeze_count > 0, but bd_fsfreeze_sb is
      *untouched* - it stays the same (now garbage) value. A subsequent
      thaw_bdev() will decide that the bd_fsfreeze_sb value is legitimate
      (since bd_fsfreeze_count > 0), and attempt to use it.
      
      Fix this by always setting bd_fsfreeze_sb to NULL when
      bd_fsfreeze_count is successfully decremented to 0 in thaw_sb().
      Alternatively, we could set bd_fsfreeze_sb to whatever
      get_active_super() returns in freeze_bdev() whenever bd_fsfreeze_count
      is successfully incremented to 1 from 0 (which can be achieved cleanly
      by moving the line currently setting bd_fsfreeze_sb to immediately
      after the "sync:" label, but it might be a little too subtle/easily
      overlooked in future).
      
      This fixes the currently panicking xfstests generic/085.
      
      Fixes: 040f04bd ("fs: simplify freeze_bdev/thaw_bdev")
      Signed-off-by: default avatarSatya Tangirala <satyat@google.com>
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      04a6a536
  4. 06 Jan, 2021 8 commits
  5. 05 Jan, 2021 3 commits
    • Ming Lei's avatar
      block: fix use-after-free in disk_part_iter_next · aebf5db9
      Ming Lei authored
      Make sure that bdgrab() is done on the 'block_device' instance before
      referring to it for avoiding use-after-free.
      
      Cc: <stable@vger.kernel.org>
      Reported-by: syzbot+825f0f9657d4e528046e@syzkaller.appspotmail.com
      Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      aebf5db9
    • Jan Kara's avatar
      bfq: Fix computation of shallow depth · 6d4d2735
      Jan Kara authored
      BFQ computes number of tags it allows to be allocated for each request type
      based on tag bitmap. However it uses 1 << bitmap.shift as number of
      available tags which is wrong. 'shift' is just an internal bitmap value
      containing logarithm of how many bits bitmap uses in each bitmap word.
      Thus number of tags allowed for some request types can be far to low.
      Use proper bitmap.depth which has the number of tags instead.
      Signed-off-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      6d4d2735
    • Tejun Heo's avatar
      blk-iocost: fix NULL iocg deref from racing against initialization · d16baa3f
      Tejun Heo authored
      When initializing iocost for a queue, its rqos should be registered before
      the blkcg policy is activated to allow policy data initiailization to lookup
      the associated ioc. This unfortunately means that the rqos methods can be
      called on bios before iocgs are attached to all existing blkgs.
      
      While the race is theoretically possible on ioc_rqos_throttle(), it mostly
      happened in ioc_rqos_merge() due to the difference in how they lookup ioc.
      The former determines it from the passed in @rqos and then bails before
      dereferencing iocg if the looked up ioc is disabled, which most likely is
      the case if initialization is still in progress. The latter looked up ioc by
      dereferencing the possibly NULL iocg making it a lot more prone to actually
      triggering the bug.
      
      * Make ioc_rqos_merge() use the same method as ioc_rqos_throttle() to look
        up ioc for consistency.
      
      * Make ioc_rqos_throttle() and ioc_rqos_merge() test for NULL iocg before
        dereferencing it.
      
      * Explain the danger of NULL iocgs in blk_iocost_init().
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Reported-by: default avatarJonathan Lemon <bsd@fb.com>
      Cc: stable@vger.kernel.org # v5.4+
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      d16baa3f
  6. 03 Jan, 2021 2 commits
  7. 29 Dec, 2020 2 commits
  8. 27 Dec, 2020 8 commits
  9. 26 Dec, 2020 4 commits