lkml.org 
[lkml]   [2020]   [Mar]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.4 086/168] vt: selection, push console lock down
    Date
    From: Jiri Slaby <jslaby@suse.cz>

    commit 4b70dd57a15d2f4685ac6e38056bad93e81e982f upstream.

    We need to nest the console lock in sel_lock, so we have to push it down
    a bit. Fortunately, the callers of set_selection_* just lock the console
    lock around the function call. So moving it down is easy.

    In the next patch, we switch the order.

    Signed-off-by: Jiri Slaby <jslaby@suse.cz>
    Fixes: 07e6124a1a46 ("vt: selection, close sel_buffer race")
    Cc: stable <stable@vger.kernel.org>
    Link: https://lore.kernel.org/r/20200228115406.5735-1-jslaby@suse.cz
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/staging/speakup/selection.c | 2 --
    drivers/tty/vt/selection.c | 13 ++++++++++++-
    drivers/tty/vt/vt.c | 2 --
    3 files changed, 12 insertions(+), 5 deletions(-)

    --- a/drivers/staging/speakup/selection.c
    +++ b/drivers/staging/speakup/selection.c
    @@ -51,9 +51,7 @@ static void __speakup_set_selection(stru
    goto unref;
    }

    - console_lock();
    set_selection_kernel(&sel, tty);
    - console_unlock();

    unref:
    tty_kref_put(tty);
    --- a/drivers/tty/vt/selection.c
    +++ b/drivers/tty/vt/selection.c
    @@ -181,7 +181,7 @@ int set_selection_user(const struct tioc
    return set_selection_kernel(&v, tty);
    }

    -int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
    +static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
    {
    struct vc_data *vc = vc_cons[fg_console].d;
    int new_sel_start, new_sel_end, spc;
    @@ -343,6 +343,17 @@ unlock:
    mutex_unlock(&sel_lock);
    return ret;
    }
    +
    +int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
    +{
    + int ret;
    +
    + console_lock();
    + ret = __set_selection_kernel(v, tty);
    + console_unlock();
    +
    + return ret;
    +}
    EXPORT_SYMBOL_GPL(set_selection_kernel);

    /* Insert the contents of the selection buffer into the
    --- a/drivers/tty/vt/vt.c
    +++ b/drivers/tty/vt/vt.c
    @@ -3046,10 +3046,8 @@ int tioclinux(struct tty_struct *tty, un
    switch (type)
    {
    case TIOCL_SETSEL:
    - console_lock();
    ret = set_selection_user((struct tiocl_selection
    __user *)(p+1), tty);
    - console_unlock();
    break;
    case TIOCL_PASTESEL:
    ret = paste_selection(tty);

    \
     
     \ /
      Last update: 2020-03-10 13:52    [W:4.261 / U:0.016 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site