Module signing exclusion for staging drivers does not work properly

[Seth Forshee]

SRU Justification

Impact: The exclusion of staging drivers from module signing and associated whitelisting are broken in xenial and zesty. In xenial even whitelisted modules aren't signed; in zesty all staging modules are signed.

Fix: Fix two implementation bugs, the first of which looks for the signature-inclusion file in the wrong location, and the second of which uses the full path to match against modules in signature-inclusion rather than just the module name.

Regression Potential: The fix is simple and trivial to test, so no regressions are expected.

---

The exclusion to module signing is broken in xenial, zesty, and artful. In xenial the mechanism will never sign any staging modules, not even those in the signature-inclusion whitelist. In zesty and artful all staging drivers are signed.

There are two problems, both related to the signature-inclusion whitelist handling. First, the path to the file is relative to where make was invoked, which only works when the source and build directories are the same (which is not the case for package builds). In xenial this means that the condition to signing always evaluates such that staging modules are not signed. However zesty and artful contain an additional check for the existence of that file which results in signing staging modules when it is not found.

The second problem is that signature-inclusion contains only the module name for staging drivers which should be signed. However the grep statement which matches against that file uses the full path to the install location of the module, which will never match.

[Kleber Sacilotto de Souza (kleber-souza)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-xenial' to 'verification-done-xenial'. If the problem still exists, change the tag 'verification-needed-xenial' to 'verification-failed-xenial'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Kleber Sacilotto de Souza (kleber-souza)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-zesty' to 'verification-done-zesty'. If the problem still exists, change the tag 'verification-needed-zesty' to 'verification-failed-zesty'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.4.0-83.106

---------------
linux (4.4.0-83.106) xenial; urgency=low

  * linux: 4.4.0-83.106 -proposed tracker (LP: #1700541)

  * CVE-2017-1000364
    - Revert "UBUNTU: SAUCE: mm: Only expand stack if guard area is hit"
    - Revert "mm: do not collapse stack gap into THP"
    - Revert "mm: enlarge stack guard gap"
    - mm: vma_adjust: remove superfluous confusing update in remove_next == 1 case
    - mm: larger stack guard gap, between vmas
    - mm: fix new crash in unmapped_area_topdown()
    - Allow stack to grow up to address space limit

linux (4.4.0-82.105) xenial; urgency=low

  * linux: 4.4.0-82.105 -proposed tracker (LP: #1699064)

  * CVE-2017-1000364
    - SAUCE: mm: Only expand stack if guard area is hit

  * linux-aws/linux-gke incorrectly producing and using linux-*-tools-
    common/linux-*-cloud-tools-common (LP: #1688579)
    - [Config] make linux-tools-common and linux-cloud-tools-common protection
      consistent

  * CVE-2017-9242
    - ipv6: fix out of bound writes in __ip6_append_data()

  * CVE-2017-9075
    - sctp: do not inherit ipv6_{mc|ac|fl}_list from parent

  * CVE-2017-9074
    - ipv6: Prevent overrun when parsing v6 header options

  * CVE-2017-9076
    - ipv6/dccp: do not inherit ipv6_mc_list from parent

  * CVE-2017-9077
    - ipv6/dccp: do not inherit ipv6_mc_list from parent

  * CVE-2017-8890
    - dccp/tcp: do not inherit mc_list from parent

  * Module signing exclusion for staging drivers does not work properly
    (LP: #1690908)
    - SAUCE: Fix module signing exclusion in package builds

  * extend-diff-ignore should use exact matches (LP: #1693504)
    - [Packaging] exact extend-diff-ignore matches

  * Dell XPS 9360 wifi 5G performance is poor (LP: #1692836)
    - SAUCE: ath10k: fix the wifi speed issue for kill 1535

  * Upgrade Redpine WLAN/BT driver to ver. 1.2.RC12 (LP: #1694607)
    - SAUCE: Redpine: Upgrade to ver. 1.2.RC12

  * [DP MST] No audio output through HDMI/DP/mDP ports in Dell WD15 and TB15
    docking stations (LP: #1694665)
    - drm/i915: Store port enum in intel_encoder
    - drm/i915: Eliminate redundant local variable definition
    - drm/i915: Switch to using port stored in intel_encoder
    - drm/i915: Move audio_connector to intel_encoder
    - drm/i915/dp: DP audio API changes for MST
    - drm/i915: abstract ddi being audio enabled
    - drm/i915/audio: extend get_saved_enc() to support more scenarios
    - drm/i915: enable dp mst audio

  * Xenial update to 4.4.70 stable release (LP: #1694621)
    - usb: misc: legousbtower: Fix buffers on stack
    - usb: misc: legousbtower: Fix memory leak
    - USB: ene_usb6250: fix DMA to the stack
    - watchdog: pcwd_usb: fix NULL-deref at probe
    - char: lp: fix possible integer overflow in lp_setup()
    - USB: core: replace %p with %pK
    - ARM: tegra: paz00: Mark panel regulator as enabled on boot
    - tpm_crb: check for bad response size
    - infiniband: call ipv6 route lookup via the stub interface
    - dm btree: fix for dm_btree_find_lowest_key()
    - dm raid: select the Kconfig option CONFIG_MD_RAID0
    - dm bufio: avoid a possible ABBA deadlock
    - dm bufio: check ...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.10.0-26.30

---------------
linux (4.10.0-26.30) zesty; urgency=low

  * linux: 4.10.0-26.30 -proposed tracker (LP: #1700528)

  * CVE-2017-1000364
    - Revert "UBUNTU: SAUCE: mm: Only expand stack if guard area is hit"
    - Revert "mm: do not collapse stack gap into THP"
    - Revert "mm: enlarge stack guard gap"
    - mm: larger stack guard gap, between vmas
    - mm: fix new crash in unmapped_area_topdown()
    - Allow stack to grow up to address space limit

linux (4.10.0-25.29) zesty; urgency=low

  * linux: 4.10.0-25.29 -proposed tracker (LP: #1699028)

  * CVE-2017-1000364
    - SAUCE: mm: Only expand stack if guard area is hit

  * CVE-2017-9074
    - ipv6: Prevent overrun when parsing v6 header options
    - ipv6: Check ip6_find_1stfragopt() return value properly.

  * [Zesty] QDF2400 ARM64 server - NMI watchdog: BUG: soft lockup - CPU#8 stuck
    for 22s! (LP: #1680549)
    - iommu/dma: Stop getting dma_32bit_pfn wrong
    - iommu/dma: Implement PCI allocation optimisation
    - iommu/dma: Convert to address-based allocation
    - iommu/dma: Clean up MSI IOVA allocation
    - iommu/dma: Plumb in the per-CPU IOVA caches
    - iommu/iova: Fix underflow bug in __alloc_and_insert_iova_range

  * Zesty update to 4.10.17 stable release (LP: #1692898)
    - xen: adjust early dom0 p2m handling to xen hypervisor behavior
    - target: Fix compare_and_write_callback handling for non GOOD status
    - target/fileio: Fix zero-length READ and WRITE handling
    - iscsi-target: Set session_fall_back_to_erl0 when forcing reinstatement
    - usb: xhci: bInterval quirk for TI TUSB73x0
    - usb: host: xhci: print correct command ring address
    - USB: serial: ftdi_sio: add device ID for Microsemi/Arrow SF2PLUS Dev Kit
    - USB: Proper handling of Race Condition when two USB class drivers try to
      call init_usb_class simultaneously
    - USB: Revert "cdc-wdm: fix "out-of-sync" due to missing notifications"
    - staging: vt6656: use off stack for in buffer USB transfers.
    - staging: vt6656: use off stack for out buffer USB transfers.
    - staging: gdm724x: gdm_mux: fix use-after-free on module unload
    - staging: wilc1000: Fix problem with wrong vif index
    - staging: comedi: jr3_pci: fix possible null pointer dereference
    - staging: comedi: jr3_pci: cope with jiffies wraparound
    - usb: misc: add missing continue in switch
    - usb: gadget: legacy gadgets are optional
    - usb: Make sure usb/phy/of gets built-in
    - usb: hub: Fix error loop seen after hub communication errors
    - usb: hub: Do not attempt to autosuspend disconnected devices
    - x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup
    - selftests/x86/ldt_gdt_32: Work around a glibc sigaction() bug
    - x86, pmem: Fix cache flushing for iovec write < 8 bytes
    - um: Fix PTRACE_POKEUSER on x86_64
    - perf/x86: Fix Broadwell-EP DRAM RAPL events
    - KVM: x86: fix user triggerable warning in kvm_apic_accept_events()
    - KVM: arm/arm64: fix races in kvm_psci_vcpu_on
    - arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP accesses
    - block: fix blk_integrity_register to use templ...