From: Oleg Nesterov <oleg@tv-sign.ru>
To: Andrew Morton <akpm@osdl.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
Steven Rostedt <rostedt@goodmis.org>,
Nick Piggin <nickpiggin@yahoo.com.au>,
Linus Torvalds <torvalds@osdl.org>,
linux-kernel@vger.kernel.org
Subject: [PATCH 1/4] for 2.6.18, revert "Drop tasklist lock in do_sched_setscheduler"
Date: Sat, 19 Aug 2006 23:30:27 +0400 [thread overview]
Message-ID: <20060819193026.GA7449@oleg> (raw)
sched_setscheduler() looks at ->signal->rlim[]. It is unsafe do dereference
->signal unless tasklist_lock or ->siglock is held (or p == current). We pin
the task structure, but this can't prevent from release_task()->__exit_signal()
which sets ->signal = NULL.
Restore tasklist_lock across the setscheduler call.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
--- 2.6.18-rc4/kernel/sched.c~1_revert 2006-08-19 17:50:56.000000000 +0400
+++ 2.6.18-rc4/kernel/sched.c 2006-08-19 18:15:15.000000000 +0400
@@ -4162,10 +4162,8 @@ do_sched_setscheduler(pid_t pid, int pol
read_unlock_irq(&tasklist_lock);
return -ESRCH;
}
- get_task_struct(p);
- read_unlock_irq(&tasklist_lock);
retval = sched_setscheduler(p, policy, &lparam);
- put_task_struct(p);
+ read_unlock_irq(&tasklist_lock);
return retval;
}
next reply other threads:[~2006-08-19 15:06 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-08-19 19:30 Oleg Nesterov [this message]
2006-08-19 19:43 ` Oleg Nesterov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20060819193026.GA7449@oleg \
--to=oleg@tv-sign.ru \
--cc=akpm@osdl.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=nickpiggin@yahoo.com.au \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=torvalds@osdl.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome