diff options
| author | Paul Fulghum <paulkf@microgate.com> | 2006-02-14 13:53:00 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-02-14 16:09:33 -0800 |
| commit | da965822abd18a17d7cffe1d511f48951c82dfb6 (patch) | |
| tree | b5a64fd33374661dbc689d3192a5c9134b3672e5 /mm | |
| parent | 16bf134840da3920ded1290973c56ec214636f12 (diff) | |
[PATCH] tty reference count fix
Fix hole where tty structure can be released when reference count is non
zero. Existing code can sleep without tty_sem protection between deciding
to release the tty structure (setting local variables tty_closing and
otty_closing) and setting TTY_CLOSING to prevent further opens. An open
can occur during this interval causing release_dev() to free the tty
structure while it is still referenced.
This should fix bugzilla.kernel.org [Bug 6041] New: Unable to handle kernel
paging request
In Bug 6041, tty_open() oopes on accessing the tty structure it has
successfully claimed. Bug was on SMP machine with the same tty being
opened and closed by multiple processes, and DEBUG_PAGEALLOC enabled.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm')
0 files changed, 0 insertions, 0 deletions