lkml.org 
[lkml]   [2018]   [Jul]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.9 30/32] PM / hibernate: Fix oops at snapshot_write()
    Date
    4.9-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

    commit fc14eebfc20854a38fd9f1d93a42b1783dad4d17 upstream.

    syzbot is reporting NULL pointer dereference at snapshot_write() [1].
    This is because data->handle is zero-cleared by ioctl(SNAPSHOT_FREE).
    Fix this by checking data_of(data->handle) != NULL before using it.

    [1] https://syzkaller.appspot.com/bug?id=828a3c71bd344a6de8b6a31233d51a72099f27fd

    Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
    Reported-by: syzbot <syzbot+ae590932da6e45d6564d@syzkaller.appspotmail.com>
    Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    kernel/power/user.c | 5 +++++
    1 file changed, 5 insertions(+)

    --- a/kernel/power/user.c
    +++ b/kernel/power/user.c
    @@ -186,6 +186,11 @@ static ssize_t snapshot_write(struct fil
    res = PAGE_SIZE - pg_offp;
    }

    + if (!data_of(data->handle)) {
    + res = -EINVAL;
    + goto unlock;
    + }
    +
    res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp,
    buf, count);
    if (res > 0)

    \
     
     \ /
      Last update: 2018-07-16 09:51    [W:2.814 / U:0.208 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site