lkml.org 
[lkml]   [2008]   [Feb]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[patch 56/73] VM/Security: add security hook to do_brk (CVE-2007-6434)
    2.6.23-stable review patch.  If anyone has any objections, please let us know.
    ------------------
    From: Eric Paris <eparis@redhat.com>

    patch ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5 in mainline.

    VM/Security: add security hook to do_brk

    Given a specifically crafted binary do_brk() can be used to get low pages
    available in userspace virtual memory and can thus be used to circumvent
    the mmap_min_addr low memory protection. Add security checks in do_brk().

    Signed-off-by: Eric Paris <eparis@redhat.com>
    Acked-by: Alan Cox <alan@redhat.com>
    Cc: Stephen Smalley <sds@tycho.nsa.gov>
    Cc: James Morris <jmorris@namei.org>
    Cc: Chris Wright <chrisw@sous-sol.org>
    Cc: maximilian attems <max@stro.at>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    mm/mmap.c | 4 ++++
    1 file changed, 4 insertions(+)

    --- a/mm/mmap.c
    +++ b/mm/mmap.c
    @@ -1938,6 +1938,10 @@ unsigned long do_brk(unsigned long addr,
    if (is_hugepage_only_range(mm, addr, len))
    return -EINVAL;

    + error = security_file_mmap(0, 0, 0, 0, addr, 1);
    + if (error)
    + return error;
    +
    flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;

    error = arch_mmap_check(addr, len, flags);
    --


    \
     
     \ /
      Last update: 2008-02-07 01:27    [W:0.039 / U:46.336 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site