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Subject[PATCH][RESEND 3] disassociate_ctty SMP fix
Hi,

the following patch, against today's BK tree, fixes a small
SMP race in disassociate_ctty. This function gets called
from do_exit, without the BKL held.

However, it sets the *tty variable before grabbing the bkl,
then makes decisions on what the variable was set to before
the lock was grabbed, despite the fact that another process
could modify its ->tty pointer in this same function.

please apply,
thank you,

Rik
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===== drivers/char/tty_io.c 1.50 vs edited =====
--- 1.50/drivers/char/tty_io.c Sat Dec 7 16:23:16 2002
+++ edited/drivers/char/tty_io.c Sat Jan 11 11:37:34 2003
@@ -571,7 +571,7 @@
*/
void disassociate_ctty(int on_exit)
{
- struct tty_struct *tty = current->tty;
+ struct tty_struct *tty;
struct task_struct *p;
struct list_head *l;
struct pid *pid;
@@ -579,6 +579,7 @@

lock_kernel();

+ tty = current->tty;
if (tty) {
tty_pgrp = tty->pgrp;
if (on_exit && tty->driver.type != TTY_DRIVER_TYPE_PTY)
-
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