1. 12 Nov, 2021 1 commit
    • Laibin Qiu's avatar
      blkcg: Remove extra blkcg_bio_issue_init · b781d8db
      Laibin Qiu authored
      KASAN reports a use-after-free report when doing block test:
      
      ==================================================================
      [10050.967049] BUG: KASAN: use-after-free in
      submit_bio_checks+0x1539/0x1550
      
      [10050.977638] Call Trace:
      [10050.978190]  dump_stack+0x9b/0xce
      [10050.979674]  print_address_description.constprop.6+0x3e/0x60
      [10050.983510]  kasan_report.cold.9+0x22/0x3a
      [10050.986089]  submit_bio_checks+0x1539/0x1550
      [10050.989576]  submit_bio_noacct+0x83/0xc80
      [10050.993714]  submit_bio+0xa7/0x330
      [10050.994435]  mpage_readahead+0x380/0x500
      [10050.998009]  read_pages+0x1c1/0xbf0
      [10051.002057]  page_cache_ra_unbounded+0x4c2/0x6f0
      [10051.007413]  do_page_cache_ra+0xda/0x110
      [10051.008207]  force_page_cache_ra+0x23d/0x3d0
      [10051.009087]  page_cache_sync_ra+0xca/0x300
      [10051.009970]  generic_file_buffered_read+0xbea/0x2130
      [10051.012685]  generic_file_read_iter+0x315/0x490
      [10051.014472]  blkdev_read_iter+0x113/0x1b0
      [10051.015300]  aio_read+0x2ad/0x450
      [10051.023786]  io_submit_one+0xc8e/0x1d60
      [10051.029855]  __se_sys_io_submit+0x125/0x350
      [10051.033442]  do_syscall_64+0x2d/0x40
      [10051.034156]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
      
      [10051.048733] Allocated by task 18598:
      [10051.049482]  kasan_save_stack+0x19/0x40
      [10051.050263]  __kasan_kmalloc.constprop.1+0xc1/0xd0
      [10051.051230]  kmem_cache_alloc+0x146/0x440
      [10051.052060]  mempool_alloc+0x125/0x2f0
      [10051.052818]  bio_alloc_bioset+0x353/0x590
      [10051.053658]  mpage_alloc+0x3b/0x240
      [10051.054382]  do_mpage_readpage+0xddf/0x1ef0
      [10051.055250]  mpage_readahead+0x264/0x500
      [10051.056060]  read_pages+0x1c1/0xbf0
      [10051.056758]  page_cache_ra_unbounded+0x4c2/0x6f0
      [10051.057702]  do_page_cache_ra+0xda/0x110
      [10051.058511]  force_page_cache_ra+0x23d/0x3d0
      [10051.059373]  page_cache_sync_ra+0xca/0x300
      [10051.060198]  generic_file_buffered_read+0xbea/0x2130
      [10051.061195]  generic_file_read_iter+0x315/0x490
      [10051.062189]  blkdev_read_iter+0x113/0x1b0
      [10051.063015]  aio_read+0x2ad/0x450
      [10051.063686]  io_submit_one+0xc8e/0x1d60
      [10051.064467]  __se_sys_io_submit+0x125/0x350
      [10051.065318]  do_syscall_64+0x2d/0x40
      [10051.066082]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
      
      [10051.067455] Freed by task 13307:
      [10051.068136]  kasan_save_stack+0x19/0x40
      [10051.068931]  kasan_set_track+0x1c/0x30
      [10051.069726]  kasan_set_free_info+0x1b/0x30
      [10051.070621]  __kasan_slab_free+0x111/0x160
      [10051.071480]  kmem_cache_free+0x94/0x460
      [10051.072256]  mempool_free+0xd6/0x320
      [10051.072985]  bio_free+0xe0/0x130
      [10051.073630]  bio_put+0xab/0xe0
      [10051.074252]  bio_endio+0x3a6/0x5d0
      [10051.074984]  blk_update_request+0x590/0x1370
      [10051.075870]  scsi_end_request+0x7d/0x400
      [10051.076667]  scsi_io_completion+0x1aa/0xe50
      [10051.077503]  scsi_softirq_done+0x11b/0x240
      [10051.078344]  blk_mq_complete_request+0xd4/0x120
      [10051.079275]  scsi_mq_done+0xf0/0x200
      [10051.080036]  virtscsi_vq_done+0xbc/0x150
      [10051.080850]  vring_interrupt+0x179/0x390
      [10051.081650]  __handle_irq_event_percpu+0xf7/0x490
      [10051.082626]  handle_irq_event_percpu+0x7b/0x160
      [10051.083527]  handle_irq_event+0xcc/0x170
      [10051.084297]  handle_edge_irq+0x215/0xb20
      [10051.085122]  asm_call_irq_on_stack+0xf/0x20
      [10051.085986]  common_interrupt+0xae/0x120
      [10051.086830]  asm_common_interrupt+0x1e/0x40
      
      ==================================================================
      
      Bio will be checked at beginning of submit_bio_noacct(). If bio needs
      to be throttled, it will start the timer and stop submit bio directly.
      Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires.
      But in the current process, if bio is throttled, it will still set bio
      issue->value by blkcg_bio_issue_init(). This is redundant and may cause
      the above use-after-free.
      
      CPU0                                   CPU1
      submit_bio
      submit_bio_noacct
        submit_bio_checks
          blk_throtl_bio()
            <=mod_timer(&sq->pending_timer
                                            blk_throtl_dispatch_work_fn
                                              submit_bio_noacct() <= bio have
                                              throttle tag, will throw directly
                                              and bio issue->value will be set
                                              here
      
                                            bio_endio()
                                            bio_put()
                                            bio_free() <= free this bio
      
          blkcg_bio_issue_init(bio)
            <= bio has been freed and
            will lead to UAF
        return BLK_QC_T_NONE
      
      Fix this by remove extra blkcg_bio_issue_init.
      
      Fixes: e439bedf (blkcg: consolidate bio_issue_init() to be a part of core)
      Signed-off-by: default avatarLaibin Qiu <qiulaibin@huawei.com>
      Link: https://lore.kernel.org/r/20211112093354.3581504-1-qiulaibin@huawei.comReviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      b781d8db
  2. 11 Nov, 2021 4 commits
  3. 10 Nov, 2021 2 commits
  4. 09 Nov, 2021 33 commits