From: Eric W. Biederman Date: Mon, 12 Feb 2007 08:52:53 +0000 (-0800) Subject: [PATCH] tty: fix the locking for signal->session in disassociate_ctty X-Git-Tag: v2.6.21-rc1~274^2~154 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2ea81868d8fba0bb56d7b45a08cc5f15dd2c6bb2;p=linux-2.6 [PATCH] tty: fix the locking for signal->session in disassociate_ctty commit 24ec839c431eb79bb8f6abc00c4e1eb3b8c4d517 while fixing the locking for signal->tty got the locking wrong for signal->session. This places our accesses of signal->session back under the tasklist_lock where they belong. Signed-off-by: Eric W. Biederman Cc: Alan Cox Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index ac937f767f..abfe24d28c 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -1496,7 +1496,6 @@ void disassociate_ctty(int on_exit) { struct tty_struct *tty; int tty_pgrp = -1; - int session; lock_kernel(); @@ -1530,7 +1529,6 @@ void disassociate_ctty(int on_exit) spin_lock_irq(¤t->sighand->siglock); current->signal->tty_old_pgrp = 0; - session = process_session(current); spin_unlock_irq(¤t->sighand->siglock); mutex_lock(&tty_mutex); @@ -1549,7 +1547,7 @@ void disassociate_ctty(int on_exit) /* Now clear signal->tty under the lock */ read_lock(&tasklist_lock); - session_clear_tty(session); + session_clear_tty(process_session(current)); read_unlock(&tasklist_lock); unlock_kernel(); }