This bug was fixed in the package linux-raspi2 - 4.15.0-1094.100

---------------
linux-raspi2 (4.15.0-1094.100) bionic; urgency=medium

  * bionic/linux-raspi2: 4.15.0-1094.100 -proposed tracker (LP: #1936562)

  [ Ubuntu: 4.15.0-154.161 ]

  * bionic/linux: 4.15.0-154.161 -proposed tracker (LP: #1938411)
  * Potential reverts of 4.19.y stable changes in 18.04 (LP: #1938537)
    - SAUCE: Revert "locking/mutex: clear MUTEX_FLAGS if wait_list is empty due to
      signal"
    - SAUCE: Revert "drm/amd/amdgpu: fix refcount leak"
  * Packaging resync (LP: #1786013)
    - [Packaging] resync getabis
    - [Packaging] update helper scripts
    - update dkms package versions
  * btrfs: Automatic balance returns -EUCLEAN and leads to forced readonly
    filesystem (LP: #1934709) // CVE-2019-19036
    - btrfs: Validate child tree block's level and first key
    - btrfs: Detect unbalanced tree with empty leaf before crashing btree
      operations
  * btrfs: Automatic balance returns -EUCLEAN and leads to forced readonly
    filesystem (LP: #1934709)
    - Revert "btrfs: Detect unbalanced tree with empty leaf before crashing btree
      operations"
    - Revert "btrfs: Validate child tree block's level and first key"
    - btrfs: Only check first key for committed tree blocks
    - btrfs: Fix wrong first_key parameter in replace_path
  * Enable fib-onlink-tests.sh and msg_zerocopy.sh in kselftests/net on Bionic
    (LP: #1934759)
    - selftests: Add fib-onlink-tests.sh to TEST_PROGS
    - selftests: net: use TEST_PROGS_EXTENDED
    - selftests/net: enable msg_zerocopy test
    - SAUCE: selftests: Make fib-onlink-tests.sh executable
  * Kernel oops due to uninitialized list on kernfs (kernfs_kill_sb)
    (LP: #1934175)
    - kernfs: deal with kernfs_fill_super() failures
    - unfuck sysfs_mount()
  * large_dir in ext4 broken (LP: #1933074)
    - SAUCE: ext4: fix directory index node split corruption
  * btrfs: Attempting to balance a nearly full filesystem with relocated root
    nodes fails (LP: #1933172) // CVE-2019-19036
    - btrfs: reloc: fix reloc root leak and NULL pointer dereference
  * btrfs: Attempting to balance a nearly full filesystem with relocated root
    nodes fails (LP: #1933172)
    - Revert "btrfs: reloc: fix reloc root leak and NULL pointer dereference"
  * Pixel format change broken for Elgato Cam Link 4K (LP: #1932367)
    - (upstream) media: uvcvideo: Fix pixel format change for Elgato Cam Link 4K
  * Bionic update: upstream stable patchset 2021-06-23 (LP: #1933375)
    - net: usb: cdc_ncm: don't spew notifications
    - efi: Allow EFI_MEMORY_XP and EFI_MEMORY_RO both to be cleared
    - efi: cper: fix snprintf() use in cper_dimm_err_location()
    - vfio/pci: Fix error return code in vfio_ecap_init()
    - vfio/pci: zap_vma_ptes() needs MMU
    - vfio/platform: fix module_put call in error flow
    - ipvs: ignore IP_VS_SVC_F_HASHED flag when adding service
    - HID: pidff: fix error return code in hid_pidff_init()
    - HID: i2c-hid: fix format string mismatch
    - netfilter: nfnetlink_cthelper: hit EBUSY on updates if size mismatches
    - ieee802154: fix error return code in ieee802154_add_iface()
    - ieee802154: fix error return code in ieee802154_llsec_getparams()
    - Bluetooth: fix the erroneous flush_work() order
    - Bluetooth: use correct lock to prevent UAF of hdev object
    - net: caif: added cfserl_release function
    - net: caif: add proper error handling
    - net: caif: fix memory leak in caif_device_notify
    - net: caif: fix memory leak in cfusbl_device_notify
    - ALSA: timer: Fix master timer notification
    - ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed
    - pid: take a reference when initializing `cad_pid`
    - ocfs2: fix data corruption by fallocate
    - nfc: fix NULL ptr dereference in llcp_sock_getname() after failed connect
    - btrfs: fix error handling in btrfs_del_csums
    - btrfs: fixup error handling in fixup_inode_link_counts
    - mm, hugetlb: fix simple resv_huge_pages underflow on UFFDIO_COPY
    - selftests/bpf: make 'dubious pointer arithmetic' test useful
    - bnxt_en: Remove the setting of dev_port.
    - KVM: SVM: Truncate GPR value for DR and CR accesses in !64-bit mode
    - sched/fair: Optimize select_idle_cpu
    - xen-pciback: redo VF placement in the virtual topology
    - ALSA: usb: update old-style static const declaration
    - nl80211: validate key indexes for cfg80211_registered_device
    - x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing
    - btrfs: return errors from btrfs_del_csums in cleanup_ref_head
    - KVM: arm64: Fix debug register indexing

 -- Juerg Haefliger <email address hidden>  Tue, 03 Aug 2021 11:20:37 +0200