Eric Lee / smarc-fsl-linux-kernel

20 Jan, 2015

1 commit

  • 926e9878a   phonet netlink: allow multiple messages per skb in route dump ... Browse Code »

    My previous patch to this file changed the code to be bug-compatible
    towards userspace. Unless userspace (which I wasn't able to find)
    implements the dump reader by hand in a wrong way, this isn't needed.
    If it uses libnl or similar code putting multiple messages into a
    single SKB is far more efficient.

    Change the code to do this. While at it, also clean it up and don't
    use so many variables - just store the address in the callback args
    directly.

    Signed-off-by: Johannes Berg
    Signed-off-by: David S. Miller

    Johannes Berg
     

18 Jan, 2015

1 commit

  • 053c095a8   netlink: make nlmsg_end() and genlmsg_end() void ... Browse Code »

    Contrary to common expectations for an "int" return, these functions
    return only a positive value -- if used correctly they cannot even
    return 0 because the message header will necessarily be in the skb.

    This makes the very common pattern of

    if (genlmsg_end(...) < 0) { ... }

    be a whole bunch of dead code. Many places also simply do

    return nlmsg_end(...);

    and the caller is expected to deal with it.

    This also commonly (at least for me) causes errors, because it is very
    common to write

    if (my_function(...))
    /* error condition */

    and if my_function() does "return nlmsg_end()" this is of course wrong.

    Additionally, there's not a single place in the kernel that actually
    needs the message length returned, and if anyone needs it later then
    it'll be very easy to just use skb->len there.

    Remove this, and make the functions void. This removes a bunch of dead
    code as described above. The patch adds lines because I did

    - return nlmsg_end(...);
    + nlmsg_end(...);
    + return 0;

    I could have preserved all the function's return values by returning
    skb->len, but instead I've audited all the places calling the affected
    functions and found that none cared. A few places actually compared
    the return value with < 0 with no change in behaviour, so I opted for the more
    efficient version.

    One instance of the error I've made numerous times now is also present
    in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
    check for
    Signed-off-by: David S. Miller

    Johannes Berg
     

25 Apr, 2014

1 commit

  • 90f62cf30   net: Use netlink_ns_capable to verify the permisions of netlink messages ... Browse Code »

    It is possible by passing a netlink socket to a more privileged
    executable and then to fool that executable into writing to the socket
    data that happens to be valid netlink message to do something that
    privileged executable did not intend to do.

    To keep this from happening replace bare capable and ns_capable calls
    with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
    Which act the same as the previous calls except they verify that the
    opener of the socket had the desired permissions as well.

    Reported-by: Andy Lutomirski
    Signed-off-by: "Eric W. Biederman"
    Signed-off-by: David S. Miller

    Eric W. Biederman
     

22 Mar, 2013

1 commit

19 Nov, 2012

1 commit

  • dfc47ef86   net: Push capable(CAP_NET_ADMIN) into the rtnl methods ... Browse Code »

    - In rtnetlink_rcv_msg convert the capable(CAP_NET_ADMIN) check
    to ns_capable(net->user-ns, CAP_NET_ADMIN). Allowing unprivileged
    users to make netlink calls to modify their local network
    namespace.

    - In the rtnetlink doit methods add capable(CAP_NET_ADMIN) so
    that calls that are not safe for unprivileged users are still
    protected.

    Later patches will remove the extra capable calls from methods
    that are safe for unprivilged users.

    Acked-by: Serge Hallyn
    Signed-off-by: "Eric W. Biederman"
    Signed-off-by: David S. Miller

    Eric W. Biederman
     

11 Sep, 2012

1 commit

  • 15e473046   netlink: Rename pid to portid to avoid confusion ... Browse Code »

    It is a frequent mistake to confuse the netlink port identifier with a
    process identifier. Try to reduce this confusion by renaming fields
    that hold port identifiers portid instead of pid.

    I have carefully avoided changing the structures exported to
    userspace to avoid changing the userspace API.

    I have successfully built an allyesconfig kernel with this change.

    Signed-off-by: "Eric W. Biederman"
    Acked-by: Stephen Hemminger
    Signed-off-by: David S. Miller

    Eric W. Biederman
     

18 Jun, 2012

1 commit

02 Apr, 2012

1 commit

10 Jun, 2011

1 commit

  • c7ac8679b   rtnetlink: Compute and store minimum ifinfo dump size ... Browse Code »

    The message size allocated for rtnl ifinfo dumps was limited to
    a single page. This is not enough for additional interface info
    available with devices that support SR-IOV and caused a bug in
    which VF info would not be displayed if more than approximately
    40 VFs were created per interface.

    Implement a new function pointer for the rtnl_register service that will
    calculate the amount of data required for the ifinfo dump and allocate
    enough data to satisfy the request.

    Signed-off-by: Greg Rose
    Signed-off-by: Jeff Kirsher

    Greg Rose
     

03 May, 2011

1 commit

  • e67f88dd1   net: dont hold rtnl mutex during netlink dump callbacks ... Browse Code »

    Four years ago, Patrick made a change to hold rtnl mutex during netlink
    dump callbacks.

    I believe it was a wrong move. This slows down concurrent dumps, making
    good old /proc/net/ files faster than rtnetlink in some situations.

    This occurred to me because one "ip link show dev ..." was _very_ slow
    on a workload adding/removing network devices in background.

    All dump callbacks are able to use RCU locking now, so this patch does
    roughly a revert of commits :

    1c2d670f366 : [RTNETLINK]: Hold rtnl_mutex during netlink dump callbacks
    6313c1e0992 : [RTNETLINK]: Remove unnecessary locking in dump callbacks

    This let writers fight for rtnl mutex and readers going full speed.

    It also takes care of phonet : phonet_route_get() is now called from rcu
    read section. I renamed it to phonet_route_get_rcu()

    Signed-off-by: Eric Dumazet
    Cc: Patrick McHardy
    Cc: Remi Denis-Courmont
    Acked-by: Stephen Hemminger
    Signed-off-by: David S. Miller

    Eric Dumazet
     

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
     

16 Mar, 2010

1 commit

19 Nov, 2009

1 commit

04 Nov, 2009

1 commit

15 Oct, 2009

1 commit

12 Sep, 2009

1 commit

25 Jun, 2009

1 commit

25 Feb, 2009

1 commit

  • 1ce85fe40   netlink: change nlmsg_notify() return value logic ... Browse Code »

    This patch changes the return value of nlmsg_notify() as follows:

    If NETLINK_BROADCAST_ERROR is set by any of the listeners and
    an error in the delivery happened, return the broadcast error;
    else if there are no listeners apart from the socket that
    requested a change with the echo flag, return the result of the
    unicast notification. Thus, with this patch, the unicast
    notification is handled in the same way of a broadcast listener
    that has set the NETLINK_BROADCAST_ERROR socket flag.

    This patch is useful in case that the caller of nlmsg_notify()
    wants to know the result of the delivery of a netlink notification
    (including the broadcast delivery) and take any action in case
    that the delivery failed. For example, ctnetlink can drop packets
    if the event delivery failed to provide reliable logging and
    state-synchronization at the cost of dropping packets.

    This patch also modifies the rtnetlink code to ignore the return
    value of rtnl_notify() in all callers. The function rtnl_notify()
    (before this patch) returned the error of the unicast notification
    which makes rtnl_set_sk_err() reports errors to all listeners. This
    is not of any help since the origin of the change (the socket that
    requested the echoing) notices the ENOBUFS error if the notification
    fails and should resync itself.

    Signed-off-by: Pablo Neira Ayuso
    Acked-by: Patrick McHardy
    Signed-off-by: David S. Miller

    Pablo Neira Ayuso
     

27 Jan, 2009

2 commits

04 Dec, 2008

1 commit

30 Sep, 2008

1 commit

23 Sep, 2008

1 commit