1. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  2. 28 Sep, 2017 1 commit
  3. 28 Aug, 2017 1 commit
  4. 09 Feb, 2017 1 commit
  5. 07 Nov, 2016 1 commit
  6. 30 Sep, 2016 3 commits
    • Juergen Gross's avatar
      xen/pciback: support driver_override · b057878b
      Juergen Gross authored
      Support the driver_override scheme introduced with commit 782a985d
      ("PCI: Introduce new device binding path using pci_dev.driver_override")
      
      As pcistub_probe() is called for all devices (it has to check for a
      match based on the slot address rather than device type) it has to
      check for driver_override set to "pciback" itself.
      
      Up to now for assigning a pci device to pciback you need something like:
      
      echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
      echo 0000:07:10.0 > /sys/bus/pci/drivers/pciback/new_slot
      echo 0000:07:10.0 > /sys/bus/pci/drivers_probe
      
      while with the patch you can use the same mechanism as for similar
      drivers like pci-stub and vfio-pci:
      
      echo pciback > /sys/bus/pci/devices/0000\:07\:10.0/driver_override
      echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
      echo 0000:07:10.0 > /sys/bus/pci/drivers_probe
      
      So e.g. libvirt doesn't need special handling for pciback.
      Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      b057878b
    • Juergen Gross's avatar
      xen/pciback: avoid multiple entries in slot list · 9f8bee9c
      Juergen Gross authored
      The Xen pciback driver has a list of all pci devices it is ready to
      seize. There is no check whether a to be added entry already exists.
      While this might be no problem in the common case it might confuse
      those which consume the list via sysfs.
      
      Modify the handling of this list by not adding an entry which already
      exists. As this will be needed later split out the list handling into
      a separate function.
      Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      9f8bee9c
    • Juergen Gross's avatar
      xen/pciback: simplify pcistub device handling · 1af916b7
      Juergen Gross authored
      The Xen pciback driver maintains a list of all its seized devices.
      There are two functions searching the list for a specific device with
      basically the same semantics just returning different structures in
      case of a match.
      
      Split out the search function.
      Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      1af916b7
  7. 06 Jul, 2016 8 commits
  8. 24 Jun, 2016 1 commit
    • Jan Beulich's avatar
      xen-pciback: return proper values during BAR sizing · d2bd05d8
      Jan Beulich authored
      Reads following writes with all address bits set to 1 should return all
      changeable address bits as one, not the BAR size (nor, as was the case
      for the upper half of 64-bit BARs, the high half of the region's end
      address). Presumably this didn't cause any problems so far because
      consumers use the value to calculate the size (usually via val & -val),
      and do nothing else with it.
      
      But also consider the exception here: Unimplemented BARs should always
      return all zeroes.
      
      And finally, the check for whether to return the sizing address on read
      for the ROM BAR should ignore all non-address bits, not just the ROM
      Enable one.
      Signed-off-by: default avatarJan Beulich <jbeulich@suse.com>
      Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      d2bd05d8
  9. 23 Jun, 2016 1 commit
    • Andrey Grodzovsky's avatar
      xen/pciback: Fix conf_space read/write overlap check. · 02ef871e
      Andrey Grodzovsky authored
      Current overlap check is evaluating to false a case where a filter
      field is fully contained (proper subset) of a r/w request.  This
      change applies classical overlap check instead to include all the
      scenarios.
      
      More specifically, for (Hilscher GmbH CIFX 50E-DP(M/S)) device driver
      the logic is such that the entire confspace is read and written in 4
      byte chunks. In this case as an example, CACHE_LINE_SIZE,
      LATENCY_TIMER and PCI_BIST are arriving together in one call to
      xen_pcibk_config_write() with offset == 0xc and size == 4.  With the
      exsisting overlap check the LATENCY_TIMER field (offset == 0xd, length
      == 1) is fully contained in the write request and hence is excluded
      from write, which is incorrect.
      Signed-off-by: default avatarAndrey Grodzovsky <andrey2805@gmail.com>
      Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Reviewed-by: default avatarJan Beulich <JBeulich@suse.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      02ef871e
  10. 21 Mar, 2016 1 commit
  11. 15 Feb, 2016 2 commits
  12. 18 Dec, 2015 7 commits
    • Doug Goldstein's avatar
      xen-pciback: fix up cleanup path when alloc fails · 584a561a
      Doug Goldstein authored
      When allocating a pciback device fails, clear the private
      field. This could lead to an use-after free, however
      the 'really_probe' takes care of setting
      dev_set_drvdata(dev, NULL) in its failure path (which we would
      exercise if the ->probe function failed), so we we
      are OK. However lets be defensive as the code can change.
      
      Going forward we should clean up the pci_set_drvdata(dev, NULL)
      in the various code-base. That will be for another day.
      Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Reported-by: default avatarJonathan Creekmore <jonathan.creekmore@gmail.com>
      Signed-off-by: default avatarDoug Goldstein <cardoe@cardoe.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      584a561a
    • Konrad Rzeszutek Wilk's avatar
      xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set. · 408fb0e5
      Konrad Rzeszutek Wilk authored
      commit f598282f ("PCI: Fix the NIU MSI-X problem in a better way")
      teaches us that dealing with MSI-X can be troublesome.
      
      Further checks in the MSI-X architecture shows that if the
      PCI_COMMAND_MEMORY bit is turned of in the PCI_COMMAND we
      may not be able to access the BAR (since they are memory regions).
      
      Since the MSI-X tables are located in there.. that can lead
      to us causing PCIe errors. Inhibit us performing any
      operation on the MSI-X unless the MEMORY bit is set.
      
      Note that Xen hypervisor with:
      "x86/MSI-X: access MSI-X table only after having enabled MSI-X"
      will return:
      xen_pciback: 0000:0a:00.1: error -6 enabling MSI-X for guest 3!
      
      When the generic MSI code tries to setup the PIRQ without
      MEMORY bit set. Which means with later versions of Xen
      (4.6) this patch is not neccessary.
      
      This is part of XSA-157
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      408fb0e5
    • Konrad Rzeszutek Wilk's avatar
      xen/pciback: For XEN_PCI_OP_disable_msi[|x] only disable if device has MSI(X) enabled. · 7cfb905b
      Konrad Rzeszutek Wilk authored
      Otherwise just continue on, returning the same values as
      previously (return of 0, and op->result has the PIRQ value).
      
      This does not change the behavior of XEN_PCI_OP_disable_msi[|x].
      
      The pci_disable_msi or pci_disable_msix have the checks for
      msi_enabled or msix_enabled so they will error out immediately.
      
      However the guest can still call these operations and cause
      us to disable the 'ack_intr'. That means the backend IRQ handler
      for the legacy interrupt will not respond to interrupts anymore.
      
      This will lead to (if the device is causing an interrupt storm)
      for the Linux generic code to disable the interrupt line.
      
      Naturally this will only happen if the device in question
      is plugged in on the motherboard on shared level interrupt GSI.
      
      This is part of XSA-157
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      7cfb905b
    • Konrad Rzeszutek Wilk's avatar
      xen/pciback: Do not install an IRQ handler for MSI interrupts. · a396f3a2
      Konrad Rzeszutek Wilk authored
      Otherwise an guest can subvert the generic MSI code to trigger
      an BUG_ON condition during MSI interrupt freeing:
      
       for (i = 0; i < entry->nvec_used; i++)
              BUG_ON(irq_has_action(entry->irq + i));
      
      Xen PCI backed installs an IRQ handler (request_irq) for
      the dev->irq whenever the guest writes PCI_COMMAND_MEMORY
      (or PCI_COMMAND_IO) to the PCI_COMMAND register. This is
      done in case the device has legacy interrupts the GSI line
      is shared by the backend devices.
      
      To subvert the backend the guest needs to make the backend
      to change the dev->irq from the GSI to the MSI interrupt line,
      make the backend allocate an interrupt handler, and then command
      the backend to free the MSI interrupt and hit the BUG_ON.
      
      Since the backend only calls 'request_irq' when the guest
      writes to the PCI_COMMAND register the guest needs to call
      XEN_PCI_OP_enable_msi before any other operation. This will
      cause the generic MSI code to setup an MSI entry and
      populate dev->irq with the new PIRQ value.
      
      Then the guest can write to PCI_COMMAND PCI_COMMAND_MEMORY
      and cause the backend to setup an IRQ handler for dev->irq
      (which instead of the GSI value has the MSI pirq). See
      'xen_pcibk_control_isr'.
      
      Then the guest disables the MSI: XEN_PCI_OP_disable_msi
      which ends up triggering the BUG_ON condition in 'free_msi_irqs'
      as there is an IRQ handler for the entry->irq (dev->irq).
      
      Note that this cannot be done using MSI-X as the generic
      code does not over-write dev->irq with the MSI-X PIRQ values.
      
      The patch inhibits setting up the IRQ handler if MSI or
      MSI-X (for symmetry reasons) code had been called successfully.
      
      P.S.
      Xen PCIBack when it sets up the device for the guest consumption
      ends up writting 0 to the PCI_COMMAND (see xen_pcibk_reset_device).
      XSA-120 addendum patch removed that - however when upstreaming said
      addendum we found that it caused issues with qemu upstream. That
      has now been fixed in qemu upstream.
      
      This is part of XSA-157
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      a396f3a2
    • Konrad Rzeszutek Wilk's avatar
      xen/pciback: Return error on XEN_PCI_OP_enable_msix when device has MSI or MSI-X enabled · 5e0ce145
      Konrad Rzeszutek Wilk authored
      The guest sequence of:
      
        a) XEN_PCI_OP_enable_msix
        b) XEN_PCI_OP_enable_msix
      
      results in hitting an NULL pointer due to using freed pointers.
      
      The device passed in the guest MUST have MSI-X capability.
      
      The a) constructs and SysFS representation of MSI and MSI groups.
      The b) adds a second set of them but adding in to SysFS fails (duplicate entry).
      'populate_msi_sysfs' frees the newly allocated msi_irq_groups (note that
      in a) pdev->msi_irq_groups is still set) and also free's ALL of the
      MSI-X entries of the device (the ones allocated in step a) and b)).
      
      The unwind code: 'free_msi_irqs' deletes all the entries and tries to
      delete the pdev->msi_irq_groups (which hasn't been set to NULL).
      However the pointers in the SysFS are already freed and we hit an
      NULL pointer further on when 'strlen' is attempted on a freed pointer.
      
      The patch adds a simple check in the XEN_PCI_OP_enable_msix to guard
      against that. The check for msi_enabled is not stricly neccessary.
      
      This is part of XSA-157
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      5e0ce145
    • Konrad Rzeszutek Wilk's avatar
      xen/pciback: Return error on XEN_PCI_OP_enable_msi when device has MSI or MSI-X enabled · 56441f3c
      Konrad Rzeszutek Wilk authored
      The guest sequence of:
      
       a) XEN_PCI_OP_enable_msi
       b) XEN_PCI_OP_enable_msi
       c) XEN_PCI_OP_disable_msi
      
      results in hitting an BUG_ON condition in the msi.c code.
      
      The MSI code uses an dev->msi_list to which it adds MSI entries.
      Under the above conditions an BUG_ON() can be hit. The device
      passed in the guest MUST have MSI capability.
      
      The a) adds the entry to the dev->msi_list and sets msi_enabled.
      The b) adds a second entry but adding in to SysFS fails (duplicate entry)
      and deletes all of the entries from msi_list and returns (with msi_enabled
      is still set).  c) pci_disable_msi passes the msi_enabled checks and hits:
      
      BUG_ON(list_empty(dev_to_msi_list(&dev->dev)));
      
      and blows up.
      
      The patch adds a simple check in the XEN_PCI_OP_enable_msi to guard
      against that. The check for msix_enabled is not stricly neccessary.
      
      This is part of XSA-157.
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      56441f3c
    • Konrad Rzeszutek Wilk's avatar
      xen/pciback: Save xen_pci_op commands before processing it · 8135cf8b
      Konrad Rzeszutek Wilk authored
      Double fetch vulnerabilities that happen when a variable is
      fetched twice from shared memory but a security check is only
      performed the first time.
      
      The xen_pcibk_do_op function performs a switch statements on the op->cmd
      value which is stored in shared memory. Interestingly this can result
      in a double fetch vulnerability depending on the performed compiler
      optimization.
      
      This patch fixes it by saving the xen_pci_op command before
      processing it. We also use 'barrier' to make sure that the
      compiler does not perform any optimization.
      
      This is part of XSA155.
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Signed-off-by: default avatarJan Beulich <JBeulich@suse.com>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      8135cf8b
  13. 29 Apr, 2015 1 commit
  14. 15 Apr, 2015 1 commit
  15. 16 Mar, 2015 2 commits
  16. 11 Mar, 2015 1 commit
  17. 04 Dec, 2014 7 commits