1. 12 4月, 2018 1 次提交
    • J
      sr: get/drop reference to device in revalidate and check_events · 2d097c50
      Jens Axboe 提交于
      We can't just use scsi_cd() to get the scsi_cd structure, we have
      to grab a live reference to the device. For both callbacks, we're
      not inside an open where we already hold a reference to the device.
      
      This fixes device removal/addition under concurrent device access,
      which otherwise could result in the below oops.
      
      NULL pointer dereference at 0000000000000010
      PGD 0 P4D 0
      Oops: 0000 [#1] PREEMPT SMP
      Modules linked in:
      sr 12:0:0:0: [sr2] scsi-1 drive
       scsi_debug crc_t10dif crct10dif_generic crct10dif_common nvme nvme_core sb_edac xl
      sr 12:0:0:0: Attached scsi CD-ROM sr2
       sr_mod cdrom btrfs xor zstd_decompress zstd_compress xxhash lzo_compress zlib_defc
      sr 12:0:0:0: Attached scsi generic sg7 type 5
       igb ahci libahci i2c_algo_bit libata dca [last unloaded: crc_t10dif]
      CPU: 43 PID: 4629 Comm: systemd-udevd Not tainted 4.16.0+ #650
      Hardware name: Dell Inc. PowerEdge T630/0NT78X, BIOS 2.3.4 11/09/2016
      RIP: 0010:sr_block_revalidate_disk+0x23/0x190 [sr_mod]
      RSP: 0018:ffff883ff357bb58 EFLAGS: 00010292
      RAX: ffffffffa00b07d0 RBX: ffff883ff3058000 RCX: ffff883ff357bb66
      RDX: 0000000000000003 RSI: 0000000000007530 RDI: ffff881fea631000
      RBP: 0000000000000000 R08: ffff881fe4d38400 R09: 0000000000000000
      R10: 0000000000000000 R11: 00000000000001b6 R12: 000000000800005d
      R13: 000000000800005d R14: ffff883ffd9b3790 R15: 0000000000000000
      FS:  00007f7dc8e6d8c0(0000) GS:ffff883fff340000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 0000000000000010 CR3: 0000003ffda98005 CR4: 00000000003606e0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       ? __invalidate_device+0x48/0x60
       check_disk_change+0x4c/0x60
       sr_block_open+0x16/0xd0 [sr_mod]
       __blkdev_get+0xb9/0x450
       ? iget5_locked+0x1c0/0x1e0
       blkdev_get+0x11e/0x320
       ? bdget+0x11d/0x150
       ? _raw_spin_unlock+0xa/0x20
       ? bd_acquire+0xc0/0xc0
       do_dentry_open+0x1b0/0x320
       ? inode_permission+0x24/0xc0
       path_openat+0x4e6/0x1420
       ? cpumask_any_but+0x1f/0x40
       ? flush_tlb_mm_range+0xa0/0x120
       do_filp_open+0x8c/0xf0
       ? __seccomp_filter+0x28/0x230
       ? _raw_spin_unlock+0xa/0x20
       ? __handle_mm_fault+0x7d6/0x9b0
       ? list_lru_add+0xa8/0xc0
       ? _raw_spin_unlock+0xa/0x20
       ? __alloc_fd+0xaf/0x160
       ? do_sys_open+0x1a6/0x230
       do_sys_open+0x1a6/0x230
       do_syscall_64+0x5a/0x100
       entry_SYSCALL_64_after_hwframe+0x3d/0xa2
      Reviewed-by: NLee Duncan <lduncan@suse.com>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      2d097c50
  2. 10 4月, 2018 14 次提交
  3. 28 3月, 2018 1 次提交
  4. 27 3月, 2018 1 次提交
  5. 26 3月, 2018 1 次提交
  6. 22 3月, 2018 22 次提交