Eric Lee / smarc-fsl-linux-kernel

15 Mar, 2011

1 commit

30 Nov, 2010

1 commit

  • 25888e303   af_unix: limit recursion level ... Browse Code »

    Its easy to eat all kernel memory and trigger NMI watchdog, using an
    exploit program that queues unix sockets on top of others.

    lkml ref : http://lkml.org/lkml/2010/11/25/8

    This mechanism is used in applications, one choice we have is to have a
    recursion limit.

    Other limits might be needed as well (if we queue other types of files),
    since the passfd mechanism is currently limited by socket receive queue
    sizes only.

    Add a recursion_level to unix socket, allowing up to 4 levels.

    Each time we send an unix socket through sendfd mechanism, we copy its
    recursion level (plus one) to receiver. This recursion level is cleared
    when socket receive queue is emptied.

    Reported-by: Марк Коренберг
    Signed-off-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Eric Dumazet
     

25 Nov, 2010

1 commit

  • 9915672d4   af_unix: limit unix_tot_inflight ... Browse Code »

    Vegard Nossum found a unix socket OOM was possible, posting an exploit
    program.

    My analysis is we can eat all LOWMEM memory before unix_gc() being
    called from unix_release_sock(). Moreover, the thread blocked in
    unix_gc() can consume huge amount of time to perform cleanup because of
    huge working set.

    One way to handle this is to have a sensible limit on unix_tot_inflight,
    tested from wait_for_unix_gc() and to force a call to unix_gc() if this
    limit is hit.

    This solves the OOM and also reduce overall latencies, and should not
    slowdown normal workloads.

    Reported-by: Vegard Nossum
    Signed-off-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Eric Dumazet
     

04 May, 2010

1 commit

30 Mar, 2010

1 commit

  • 5a0e3ad6a   include cleanup: Update gfp.h and slab.h includes to prepare for breaking implic… ... Browse Code »

    …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

03 Dec, 2008

1 commit

27 Nov, 2008

1 commit

  • 5f23b7349   net: Fix soft lockups/OOM issues w/ unix garbage collector ... Browse Code »

    This is an implementation of David Miller's suggested fix in:
    https://bugzilla.redhat.com/show_bug.cgi?id=470201

    It has been updated to use wait_event() instead of
    wait_event_interruptible().

    Paraphrasing the description from the above report, it makes sendmsg()
    block while UNIX garbage collection is in progress. This avoids a
    situation where child processes continue to queue new FDs over a
    AF_UNIX socket to a parent which is in the exit path and running
    garbage collection on these FDs. This contention can result in soft
    lockups and oom-killing of unrelated processes.

    Signed-off-by: dann frazier
    Signed-off-by: David S. Miller

    dann frazier
     

12 Nov, 2008

1 commit

10 Nov, 2008

1 commit

  • 6209344f5   net: unix: fix inflight counting bug in garbage collector ... Browse Code »

    Previously I assumed that the receive queues of candidates don't
    change during the GC. This is only half true, nothing can be received
    from the queues (see comment in unix_gc()), but buffers could be added
    through the other half of the socket pair, which may still have file
    descriptors referring to it.

    This can result in inc_inflight_move_tail() erronously increasing the
    "inflight" counter for a unix socket for which dec_inflight() wasn't
    previously called. This in turn can trigger the "BUG_ON(total_refs <
    inflight_refs)" in a later garbage collection run.

    Fix this by only manipulating the "inflight" counter for sockets which
    are candidates themselves. Duplicating the file references in
    unix_attach_fds() is also needed to prevent a socket becoming a
    candidate for GC while the skb that contains it is not yet queued.

    Reported-by: Andrea Bittau
    Signed-off-by: Miklos Szeredi
    CC: stable@kernel.org
    Signed-off-by: Linus Torvalds

    Miklos Szeredi
     

02 Nov, 2008

1 commit

27 Jul, 2008

1 commit

11 Nov, 2007

2 commits

12 Jul, 2007

1 commit

  • 1fd05ba5a   [AF_UNIX]: Rewrite garbage collector, fixes race. ... Browse Code »

    Throw out the old mark & sweep garbage collector and put in a
    refcounting cycle detecting one.

    The old one had a race with recvmsg, that resulted in false positives
    and hence data loss. The old algorithm operated on all unix sockets
    in the system, so any additional locking would have meant performance
    problems for all users of these.

    The new algorithm instead only operates on "in flight" sockets, which
    are very rare, and the additional locking for these doesn't negatively
    impact the vast majority of users.

    In fact it's probable, that there weren't *any* heavy senders of
    sockets over sockets, otherwise the above race would have been
    discovered long ago.

    The patch works OK with the app that exposed the race with the old
    code. The garbage collection has also been verified to work in a few
    simple cases.

    Signed-off-by: Miklos Szeredi
    Signed-off-by: David S. Miller

    Miklos Szeredi
     

15 Feb, 2007

1 commit

  • cd354f1ae   [PATCH] remove many unneeded #includes of sched.h ... Browse Code »

    After Al Viro (finally) succeeded in removing the sched.h #include in module.h
    recently, it makes sense again to remove other superfluous sched.h includes.
    There are quite a lot of files which include it but don't actually need
    anything defined in there. Presumably these includes were once needed for
    macros that used to live in sched.h, but moved to other header files in the
    course of cleaning it up.

    To ease the pain, this time I did not fiddle with any header files and only
    removed #includes from .c-files, which tend to cause less trouble.

    Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
    arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
    allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
    configs in arch/arm/configs on arm. I also checked that no new warnings were
    introduced by the patch (actually, some warnings are removed that were emitted
    by unnecessarily included header files).

    Signed-off-by: Tim Schmielau
    Acked-by: Russell King
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Tim Schmielau
     

11 Feb, 2007

1 commit

09 Dec, 2006

1 commit

21 Mar, 2006

1 commit

  • 4a3e2f711   [NET] sem2mutex: net/ ... Browse Code »

    Semaphore to mutex conversion.

    The conversion was generated via scripts, and the result was validated
    automatically via a script as well.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: David S. Miller

    Arjan van de Ven
     

04 Jan, 2006

1 commit

30 Aug, 2005

2 commits

  • c752f0739   [TCP]: Move the tcp sock states to net/tcp_states.h ... Browse Code »

    Lots of places just needs the states, not even linux/tcp.h, where this
    enum was, needs it.

    This speeds up development of the refactorings as less sources are
    rebuilt when things get moved from net/tcp.h.

    Signed-off-by: Arnaldo Carvalho de Melo
    Signed-off-by: David S. Miller

    Arnaldo Carvalho de Melo
     
  • 8728b834b   [NET]: Kill skb->list ... Browse Code »

    Remove the "list" member of struct sk_buff, as it is entirely
    redundant. All SKB list removal callers know which list the
    SKB is on, so storing this in sk_buff does nothing other than
    taking up some space.

    Two tricky bits were SCTP, which I took care of, and two ATM
    drivers which Francois Romieu fixed
    up.

    Signed-off-by: David S. Miller
    Signed-off-by: Francois Romieu

    David S. Miller
     

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds