CVE-2010-4248

[Brad Figg]

posix-cpu-timers.c correctly assumes that the dying process does
posix_cpu_timers_exit_group() and removes all !CPUCLOCK_PERTHREAD
timers from signal->cpu_timers list.

But, it also assumes that timer->it.cpu.task is always the group
leader, and thus the dead ->task means the dead thread group.

This is obviously not true after de_thread() changes the leader.
After that almost every posix_cpu_timer_ method has problems.

It is not simple to fix this bug correctly. First of all, I think
that timer->it.cpu should use struct pid instead of task_struct.
Also, the locking should be reworked completely. In particular,
tasklist_lock should not be used at all. This all needs a lot of
nontrivial and hard-to-test changes.

Change __exit_signal() to do posix_cpu_timers_exit_group() when
the old leader dies during exec. This is not the fix, just the
temporary hack to hide the problem for 2.6.37 and stable. IOW,
this is obviously wrong but this is what we currently have anyway:
cpu timers do not work after mt exec.

In theory this change adds another race. The exiting leader can
detach the timers which were attached to the new leader. However,
the window between de_thread() and release_task() is small, we
can pretend that sys_timer_create() was called before de_thread().

[Brad Figg (brad-figg)]

The upstream commit for this patch is e0a70217107e6f9844628120412cb27bb4cea194

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 2.6.24-28.86

---------------
linux (2.6.24-28.86) hardy-proposed; urgency=low

  [ Brad Figg ]

  * Release Tracking Bug
    - LP: #716166

  [Tim Gardner]

  * xen unified block-device I/O interface back end can orphan devices,
    CVE-2010-3699
    - LP: #708019
    - CVE-2010-3699

  [Upstream Kernel Changes]

  * Hardy SRU: thinkpad-acpi: lock down video output state access,
    CVE-2010-3448
    - LP: #706999
    - CVE-2010-3448
  * net: Limit socket I/O iovec total length to INT_MAX., CVE-2010-3859
    - LP: #711855, #708839
    - CVE-2010-4160
  * net: Truncate recvfrom and sendto length to INT_MAX., CVE-2010-3859
    - LP: #711855, #708839
    - CVE-2010-4160
  * net: ax25: fix information leak to userland, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * net: ax25: fix information leak to userland harder, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * memory corruption in X.25 facilities parsing, CVE-2010-3873
    - LP: #709372
    - CVE-2010-3873
  * net: packet: fix information leak to userland, CVE-2010-3876
    - LP: #710714
    - CVE-2010-3876
  * net: tipc: fix information leak to userland, CVE-2010-3877
    - LP: #711291
    - CVE-2010-3877
  * KVM: VMX: fix vmx null pointer dereference on debug register access,
    CVE-2010-0435
    - LP: #712615
    - CVE-2010-0435
  * gdth: integer overflow in ioctl, CVE-2010-4157
    - LP: #711797
    - CVE-2010-4157
  * posix-cpu-timers: workaround to suppress the problems with mt exec,
    CVE-2010-4248
    - LP: #712609
    - CVE-2010-4248
  * ALSA: sound/pci/rme9652: prevent reading uninitialized stack memory,
    CVE-2010-4080, CVE-2010-4081
    - LP: #712723, #712737
    - CVE-2010-4081
  * sys_semctl: fix kernel stack leakage, CVE-2010-4083
    - LP: #712749
    - CVE-2010-4083
  * inet_diag: Make sure we actually run the same bytecode we audited,
    CVE-2010-3880
    - LP: #711865
    - CVE-2010-3880

linux (2.6.24-28.85) hardy-proposed; urgency=low

  [ Brad Figg ]

  * Tracking Bug
    - LP: #708315

  [Upstream Kernel Changes]

  * ata_piix: IDE mode SATA patch for Intel ICH10 DeviceID's
    - LP: #693401
  * USB: serial/mos*: prevent reading uninitialized stack memory,
    CVE-2010-4074
    - LP: #706149
    - CVE-2010-4074
  * KVM: Fix fs/gs reload oops with invalid ldt
    - LP: #707000
    - CVE-2010-3698
  * drivers/video/sis/sis_main.c: prevent reading uninitialized stack
    memory, CVE-2010-4078
    - LP: #707579
    - CVE-2010-4078
  * V4L/DVB: ivtvfb: prevent reading uninitialized stack memory,
    CVE-2010-4079
    - LP: #707649
    - CVE-2010-4079

linux (2.6.24-28.84) hardy-proposed; urgency=low

  [ Steve Conklin ]

  * Tracking Bug
    - LP: #698185

linux (2.6.24-28.83) hardy-proposed; urgency=low

  [ Steve Conklin ]
  * tracking bug moved from here to latest entry

linux (2.6.24-28.82) hardy-proposed; urgency=low

  [ Leann Ogasawara ]

  * Revert "SAUCE: AF_ECONET saddr->cookie prevent NULL pointer
    dereference"
  * Revert "SAUCE: AF_ECONET SIOCSIFADDR ioctl does not check privileges"
  * Revert "SAUCE: AF_ECONET prevent kernel stack overflow"

  [Upstream Kernel Changes]

  * xfs: validate untrust...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 2.6.31-22.73

---------------
linux (2.6.31-22.73) karmic-proposed; urgency=low

  [ Steve Conklin ]

  * Release Tracking Bug
    - LP: #716648

  [ Upstream Kernel Changes ]

  * copied ABI directory
  * net: Limit socket I/O iovec total length to INT_MAX., CVE-2010-3859
    - LP: #708839, #711855
    - CVE-2010-4160
  * net: Truncate recvfrom and sendto length to INT_MAX., CVE-2010-3859
    - LP: #708839, #711855
    - CVE-2010-4160
  * net: fix rds_iovec page count overflow, CVE-2010-3865
    - LP: #709153
    - CVE-2010-3865
  * net: ax25: fix information leak to userland, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * net: ax25: fix information leak to userland harder, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * can-bcm: fix minor heap overflow
    - LP: #710680
    - CVE-2010-3874
  * memory corruption in X.25 facilities parsing, CVE-2010-3873
    - LP: #709372
    - CVE-2010-3873
  * net: packet: fix information leak to userland, CVE-2010-3876
    - LP: #710714
    - CVE-2010-3876
  * net: tipc: fix information leak to userland, CVE-2010-3877
    - LP: #711291
    - CVE-2010-3877
  * KVM: VMX: fix vmx null pointer dereference on debug register access,
    CVE-2010-0435
    - LP: #712615
    - CVE-2010-0435
  * gdth: integer overflow in ioctl, CVE-2010-4157
    - LP: #711797
    - CVE-2010-4157
  * posix-cpu-timers: workaround to suppress the problems with mt exec,
    CVE-2010-4248
    - LP: #712609
    - CVE-2010-4248
  * ALSA: sound/pci/rme9652: prevent reading uninitialized stack memory,
    CVE-2010-4080, CVE-2010-4081
    - LP: #712723, #712737
    - CVE-2010-4081
  * drivers/video/via/ioctl.c: prevent reading uninitialized stack memory,
    CVE-2010-4082
    - LP: #712744
    - CVE-2010-4082
  * sys_semctl: fix kernel stack leakage, CVE-2010-4083
    - LP: #712749
    - CVE-2010-4083
  * inet_diag: Make sure we actually run the same bytecode we audited,
    CVE-2010-3880
    - LP: #711865
    - CVE-2010-3880

linux (2.6.31-22.72) karmic-proposed; urgency=low

  [ Brad Figg ]

  * Tracking Bug
    - LP: #708860

  [ Upstream Kernel Changes ]

  * Karmic SRU: thinkpad-acpi: lock down video output state access, CVE-2010-3448
    - LP: #706999
    - CVE-2010-3448
  * USB: serial/mos*: prevent reading uninitialized stack memory,
    CVE-2010-4074
    - LP: #706149
    - CVE-2010-4074
  * KVM: Fix fs/gs reload oops with invalid ldt
    - LP: #707000
    - CVE-2010-3698
  * drivers/video/sis/sis_main.c: prevent reading uninitialized stack
    memory, CVE-2010-4078
    - LP: #707579
    - CVE-2010-4078
  * V4L/DVB: ivtvfb: prevent reading uninitialized stack memory,
    CVE-2010-4079
    - LP: #707649
    - CVE-2010-4079

linux (2.6.31-22.71) karmic-proposed; urgency=low

  [ Brad Figg ]

  - LP: #698214

  [ Upstream Kernel Changes ]

  * ipc: initialize structure memory to zero for compat functions
  * tcp: Increase TCP_MAXSEG socket option minimum.
    - CVE-2010-4165
  * perf_events: Fix perf_counter_mmap() hook in mprotect()
    - CVE-2010-4169
  * af_unix: limit unix_tot_inflight
    - CVE-2010-4249
 -- Steve Conklin <email address hidden> Thu, 10 Feb 2011 13:49:49...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 2.6.35-27.48

---------------
linux (2.6.35-27.48) maverick-proposed; urgency=low

  [ Steve Conklin ]

  * Release Tracking Bug
    - LP: #723335

  [ Upstream Kernel Changes ]

  * thinkpad-acpi: avoid keymap pitfall
    - LP: #722747

linux (2.6.35-27.47) maverick-proposed; urgency=low

  [ Brad Figg ]

  * Release Tracking Bug
    - LP: #716532

  [ Upstream Kernel Changes ]

  * Revert "USB: gadget: Allow function access to device ID data during
    bind()"
    - LP: #714732
  * net: fix rds_iovec page count overflow, CVE-2010-3865
    - LP: #709153
    - CVE-2010-3865
  * Input: fix typo in keycode validation supporting large scancodes
    - LP: #658198
  * net: ax25: fix information leak to userland, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * net: ax25: fix information leak to userland harder, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * net: packet: fix information leak to userland, CVE-2010-3876
    - LP: #710714
    - CVE-2010-3876
  * net: tipc: fix information leak to userland, CVE-2010-3877
    - LP: #711291
    - CVE-2010-3877
  * posix-cpu-timers: workaround to suppress the problems with mt exec,
    CVE-2010-4248
    - LP: #712609
    - CVE-2010-4248
  * sys_semctl: fix kernel stack leakage, CVE-2010-4083
    - LP: #712749
    - CVE-2010-4083
  * thinkpad-acpi: lock down size of hotkey keymap
    - LP: #712174
  * thinkpad-acpi: add support for model-specific keymaps
    - LP: #712174
  * thinkpad-acpi: Add KEY_CAMERA (Fn-F6) for Lenovo keyboards
    - LP: #712174
  * x86, hotplug: Use mwait to offline a processor, fix the legacy case
    - LP: #714732
  * fuse: verify ioctl retries
    - LP: #714732
  * fuse: fix ioctl when server is 32bit
    - LP: #714732
  * ALSA: hda: Use position_fix=1 for Acer Aspire 5538 to enable capture on
    internal mic
    - LP: #685161, #714732
  * ALSA: hda: Use model=lg quirk for LG P1 Express to enable playback and
    capture
    - LP: #595482, #714732
  * drm/radeon/kms: don't apply 7xx HDP flush workaround on AGP
    - LP: #714732
  * drm/kms: remove spaces from connector names (v2)
    - LP: #714732
  * drm/radeon/kms: fix vram base calculation on rs780/rs880
    - LP: #714732
  * nohz: Fix printk_needs_cpu() return value on offline cpus
    - LP: #714732
  * nohz: Fix get_next_timer_interrupt() vs cpu hotplug
    - LP: #714732
  * nfsd: Fix possible BUG_ON firing in set_change_info
    - LP: #714732
  * NFS: Fix fcntl F_GETLK not reporting some conflicts
    - LP: #714732
  * sunrpc: prevent use-after-free on clearing XPT_BUSY
    - LP: #714732
  * hwmon: (adm1026) Allow 1 as a valid divider value
    - LP: #714732
  * hwmon: (adm1026) Fix setting fan_div
    - LP: #714732
  * EDAC: Fix workqueue-related crashes
    - LP: #714732
  * amd64_edac: Fix interleaving check
    - LP: #714732
  * ASoC: Fix swap of left and right channels for WM8993/4 speaker boost
    gain
    - LP: #714732
  * ASoC: Fix off by one error in WM8994 EQ register bank size
    - LP: #714732
  * ASoC: WM8580: Fix R8 initial value
    - LP: #714732
  * ASoC: fix deemphasis control in wm8904/55/60 codecs
    - LP: #714732
  * bootmem: Add alloc_bootmem_...

[Paolo Pisati (p-pisati)]

karmic is EOL

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-fsl-imx51 - 2.6.31-609.26

---------------
linux-fsl-imx51 (2.6.31-609.26) lucid; urgency=low

  [ Paolo Pisati ]

  * Tracking bug
    - LP: #795219
  * [Config] Disable parport_pc on fsl-imx51
    - LP: #601226

  [ Upstream Kernel Changes ]

  * ALSA: sound/pci/rme9652: prevent reading uninitialized stack memory
    - LP: #712723, #712737
  * can-bcm: fix minor heap overflow
    - LP: #710680
  * drivers/video/via/ioctl.c: prevent reading uninitialized stack memory
    - LP: #712744
  * gdth: integer overflow in ioctl
    - LP: #711797
  * inet_diag: Make sure we actually run the same bytecode we audited, CVE-2010-3880
    - LP: #711865
    - CVE-2010-3880
  * net: fix rds_iovec page count overflow, CVE-2010-3865
    - LP: #709153
    - CVE-2010-3865
  * net: packet: fix information leak to userland, CVE-2010-3876
    - LP: #711045
    - CVE-2010-3876
  * net: tipc: fix information leak to userland, CVE-2010-3877
    - LP: #711291
    - CVE-2010-3877
  * net: Truncate recvfrom and sendto length to INT_MAX.
    - LP: #708839
  * posix-cpu-timers: workaround to suppress the problems with mt exec
    - LP: #712609
  * sys_semctl: fix kernel stack leakage
    - LP: #712749
  * x25: Patch to fix bug 15678 - x25 accesses fields beyond end of packet.
    - LP: #709372
  * memory corruption in X.25 facilities parsing
    - LP: #709372
  * net: ax25: fix information leak to userland, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * net: ax25: fix information leak to userland harder, CVE-2010-3875
    - LP: #710714
    - CVE-2010-3875
  * fs/partitions/ldm.c: fix oops caused by corrupted partition table, CVE-2011-1017
    - LP: #771382
    - CVE-2011-1017
  * net: clear heap allocations for privileged ethtool actions
    - LP: #771445
  * Prevent rt_sigqueueinfo and rt_tgsigqueueinfo from spoofing the signal code
    - LP: #772543
  * Relax si_code check in rt_sigqueueinfo and rt_tgsigqueueinfo
    - LP: #772543
  * exec: make argv/envp memory visible to oom-killer
    - LP: #768408
  * next_pidmap: fix overflow condition
    - LP: #784727
  * proc: do proper range check on readdir offset
    - LP: #784727
  * mpt2sas: prevent heap overflows and unchecked reads
    - LP: #787145
  * agp: fix arbitrary kernel memory writes
    - LP: #788684
  * can: add missing socket check in can/raw release
    - LP: #788694
  * agp: fix OOM and buffer overflow
    - LP: #788700
  * do_exit(): make sure that we run with get_fs() == USER_DS - CVE-2010-4258
    - LP: #723945
    - CVE-2010-4258
  * x25: Prevent crashing when parsing bad X.25 facilities - CVE-2010-4164
    - LP: #731199
    - CVE-2010-4164
  * install_special_mapping skips security_file_mmap check - CVE-2010-4346
    - LP: #731971
    - CVE-2010-4346
  * econet: Fix crash in aun_incoming() - CVE-2010-4342
    - LP: #736394
    - CVE-2010-4342
  * sound: Prevent buffer overflow in OSS load_mixer_volumes - CVE-2010-4527
    - LP: #737073
    - CVE-2010-4527
  * irda: prevent integer underflow in IRLMP_ENUMDEVICES, CVE-2010-4529
    - LP: #737823
    - CVE-2010-4529
  * CAN: Use inode instead of kernel address for /proc file - CVE-2010-4565
    - LP: #765007...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-ti-omap4 - 2.6.35-903.24

---------------
linux-ti-omap4 (2.6.35-903.24) maverick-proposed; urgency=low

  * Release tracking bug
    - LP: #838037

  [ Upstream Kernel Changes ]

  * ipv6: make fragment identifications less predictable, CVE-2011-2699
    - LP: #827685
    - CVE-2011-2699
  * perf: Fix software event overflow, CVE-2011-2918
    - LP: #834121
    - CVE-2011-2918
  * proc: fix oops on invalid /proc/<pid>/maps access, CVE-2011-1020
    - LP: #813026
    - CVE-2011-1020

linux-ti-omap4 (2.6.35-903.23) maverick-proposed; urgency=low

  * Release tracking bug
    - LP: #829655

  [ Upstream Kernel Changes ]

  * drm/radeon/kms: check AA resolve registers on r300, CVE-2011-1016
    - LP: #745686
    - CVE-2011-1016
  * drm/radeon: fix regression with AA resolve checking, CVE-2011-1016
    - LP: #745686
    - CVE-2011-1016
  * can-bcm: fix minor heap overflow
    - LP: #690730
  * CAN: Use inode instead of kernel address for /proc file, CVE-2010-4565
    - LP: #765007
    - CVE-2010-4565
  * av7110: check for negative array offset
    - LP: #747520
  * xfs: prevent leaking uninitialized stack memory in FSGEOMETRY_V1,
    CVE-2011-0711
    - LP: #767740
    - CVE-2011-0711
  * ALSA: caiaq - Fix possible string-buffer overflow
    - LP: #747520
  * IB/cm: Bump reference count on cm_id before invoking callback,
    CVE-2011-0695
    - LP: #770369
    - CVE-2011-0695
  * RDMA/cma: Fix crash in request handlers, CVE-2011-0695
    - LP: #770369
    - CVE-2011-0695
  * Treat writes as new when holes span across page boundaries,
    CVE-2011-0463
    - LP: #770483
    - CVE-2011-0463
  * net: clear heap allocations for privileged ethtool actions
    - LP: #686158
  * usb: iowarrior: don't trust report_size for buffer size
    - LP: #747520
  * fs/partitions/ldm.c: fix oops caused by corrupted partition table,
    CVE-2011-1017
    - LP: #771382
    - CVE-2011-1017
  * Prevent rt_sigqueueinfo and rt_tgsigqueueinfo from spoofing the signal
    code
    - LP: #747520
  * Relax si_code check in rt_sigqueueinfo and rt_tgsigqueueinfo
    - LP: #747520
  * exec: make argv/envp memory visible to oom-killer
    - LP: #690730
  * next_pidmap: fix overflow condition
    - LP: #772560
  * proc: do proper range check on readdir offset
    - LP: #772560
  * ALSA: sound/pci/asihpi: check adapter index in hpi_ioctl, CVE-2011-1169
    - LP: #785331
    - CVE-2011-1169
  * mpt2sas: prevent heap overflows and unchecked reads, CVE-2011-1494
    - LP: #787145
    - CVE-2011-1494
  * agp: fix arbitrary kernel memory writes, CVE-1011-2022
    - LP: #788684
    - CVE-1011-2022
  * can: add missing socket check in can/raw release, CVE-2011-1748
    - LP: #788694
    - CVE-2011-1748
  * agp: fix OOM and buffer overflow
    - LP: #788700
  * drivers/net/cxgb3/cxgb3_main.c: prevent reading uninitialized stack
    memory - CVE-2010-3296
    - CVE-2010-3296
  * drivers/net/eql.c: prevent reading uninitialized stack memory -
    CVE-2010-3297
    - CVE-2010-3297
  * inet_diag: Make sure we actually run the same bytecode we audited,
    CVE-2010-3880
    - LP: #711865
    - CVE-2010-3880
  * setup_arg_pages: diagnose excessive argume...