lkml.org 
[lkml]   [2011]   [Sep]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v3] Make PTRACE_SEIZE set ptrace options specified in 'data'
    On Thu, Sep 08, 2011 at 08:22:04PM +0200, Denys Vlasenko wrote:
    > Make PTRACE_SEIZE set ptrace options specified in 'data' parameter
    >
    > This can be used to close a few corner cases in strace where we get
    > unwanted racy behavior after attach, but before we have a chance
    > to set options (the notorious post-execve SIGTRAP comes to mind),
    > and removes the need to track "did we set opts for this task" state
    > in strace internals.
    >
    > While we are at it:
    >
    > Make it possible to extend SEIZE in the future with more functionality
    > by passing non-zero 'addr' parameter.
    > To that end, error out if 'addr' is non-zero.
    > PTRACE_ATTACH did not (and still does not) have such check,
    > and users (strace) do pass garbage there... let's avoid repeating
    > this mistake with SEIZE.
    >
    > Set all task->ptrace bits in one operation - before this change,
    > we were adding PT_SEIZED and PT_PTRACE_CAP with task->ptrace |= BIT ops.
    > This was probably ok (not a bug), but let's be on a safer side.
    >
    > Changes since v2: use (unsigned long) casts instead of (long) ones,
    > move PTRACE_SEIZE_DEVEL-related code to separate lines of code.
    >
    >
    > Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

    Acked-by: Tejun Heo <tj@kernel.org>

    Thanks.

    --
    tejun


    \
     
     \ /
      Last update: 2011-09-11 01:37    [W:0.020 / U:60.612 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site