lkml.org 
[lkml]   [2009]   [Dec]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH BUGFIX] [RESEND] mm: Pass mm->flags as a coredump parameter for consistency
    Date
    > Pass mm->flags as a coredump parameter for consistency.
    >
    > ---
    > 1787 if (mm->core_state || !get_dumpable(mm)) { <- (1)
    > 1788 up_write(&mm->mmap_sem);
    > 1789 put_cred(cred);
    > 1790 goto fail;
    > 1791 }
    > 1792
    > [...]
    > 1798 if (get_dumpable(mm) == 2) { /* Setuid core dump mode */ <-(2)
    > 1799 flag = O_EXCL; /* Stop rewrite attacks */
    > 1800 cred->fsuid = 0; /* Dump root private */
    > 1801 }
    > ---
    >
    > Since dumpable bits are not protected by lock, there is a
    > chance to change these bits between (1) and (2).
    >
    > To solve this issue, this patch copies mm->flags to
    > coredump_params.mm_flags at the beginning of do_coredump() and uses it instead of get_dumpable() while dumping core.
    >
    > This copy is also passed to binfmt->core_dump, since
    > elf*_core_dump() uses dump_filter bits in mm->flags.
    >
    > Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
    > Cc: Roland McGrath <roland@redhat.com>
    > Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
    > Cc: Andrew Morton <akpm@linux-foundation.org>
    > Cc: Oleg Nesterov <oleg@redhat.com>
    > Cc: Ingo Molnar <mingo@elte.hu>
    > Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>

    looks good to me.
    Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>






    \
     
     \ /
      Last update: 2009-12-21 02:55    [W:0.023 / U:30.280 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site