s390/pci: fix use after free in dma_init

[bugproxy]

== Comment: #0 - Hendrik Brueckner <email address hidden> - 2016-05-23 09:09:00 ==
Please backport upstream Linux commit ID:

commit dba599091c191d209b1499511a524ad9657c0e5a
Author: Sebastian Ott <email address hidden>
Date: Fri Apr 15 09:41:35 2016 +0200

    s390/pci: fix use after free in dma_init

    After a failure during registration of the dma_table (because of the
    function being in error state) we free its memory but don't reset the
    associated pointer to zero.

    When we then receive a notification from firmware (about the function
    being in error state) we'll try to walk and free the dma_table again.

    Fix this by resetting the dma_table pointer. In addition to that make
    sure that we free the iommu_bitmap when appropriate.

    Signed-off-by: Sebastian Ott <email address hidden>
    Reviewed-by: Gerald Schaefer <email address hidden>
    Signed-off-by: Martin Schwidefsky <email address hidden>

[Tim Gardner (timg-tpi)]

released with 4.6

[Kamal Mostafa (kamalmostafa)]

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 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!

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2016-06-14 12:31 EDT-------
I verified that the kernel in -proposed (4.4.0-25.44) fixes the problem.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.4.0-28.47

---------------
linux (4.4.0-28.47) xenial; urgency=low

  [ Luis Henriques ]

  * Release Tracking Bug
    - LP: #1595874

  * Linux netfilter local privilege escalation issues (LP: #1595350)
    - netfilter: x_tables: don't move to non-existent next rule
    - netfilter: x_tables: validate targets of jumps
    - netfilter: x_tables: add and use xt_check_entry_offsets
    - netfilter: x_tables: kill check_entry helper
    - netfilter: x_tables: assert minimum target size
    - netfilter: x_tables: add compat version of xt_check_entry_offsets
    - netfilter: x_tables: check standard target size too
    - netfilter: x_tables: check for bogus target offset
    - netfilter: x_tables: validate all offsets and sizes in a rule
    - netfilter: x_tables: don't reject valid target size on some architectures
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    - netfilter: ip_tables: simplify translate_compat_table args
    - netfilter: ip6_tables: simplify translate_compat_table args
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    - netfilter: x_tables: do compat validation via translate_table
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  * Linux netfilter IPT_SO_SET_REPLACE memory corruption (LP: #1555338)
    - netfilter: x_tables: validate e->target_offset early
    - netfilter: x_tables: make sure e->next_offset covers remaining blob size
    - netfilter: x_tables: fix unconditional helper

linux (4.4.0-27.46) xenial; urgency=low

  [ Kamal Mostafa ]

  * Release Tracking Bug
    - LP: #1594906

  * Support Edge Gateway's Bluetooth LED (LP: #1512999)
    - Revert "UBUNTU: SAUCE: Bluetooth: Support for LED on Marvell modules"

linux (4.4.0-26.45) xenial; urgency=low

  [ Kamal Mostafa ]

  * Release Tracking Bug
    - LP: #1594442

  * linux: Implement secure boot state variables (LP: #1593075)
    - SAUCE: UEFI: Add secure boot and MOK SB State disabled sysctl

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    - ethtool.h: define INT_MAX for userland

linux (4.4.0-25.44) xenial; urgency=low

  [ Kamal Mostafa ]

  * Release Tracking Bug
    - LP: #1591289

  * Xenial update to v4.4.13 stable release (LP: #1590455)
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