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Date:   Tue, 17 Oct 2023 21:07:10 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Dmitry Safonov <0x7f454c46@gmail.com>
Cc:     mingo@kernel.org, frederic@kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        tglx@linutronix.de,
        syzbot <syzbot+3908cdfd655fd839c82f@syzkaller.appspotmail.com>
Subject: Re: [syzbot] [kernel?] KASAN: slab-use-after-free Read in
 reweight_entity
Message-ID: <20231017190710.GF1599@noisy.programming.kicks-ass.net>
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On Tue, Oct 17, 2023 at 07:58:56PM +0100, Dmitry Safonov wrote:
> FWIW,
> Managed to locally reproduce it twice on 58720809f527 (tag: v6.6-rc6)
> Linux 6.6-rc6 + TCP-AO patches on the top.
> (but can't reproduce reliably at will)
> 
> [dima@Mindolluin linux-tcp-ao]$ ./scripts/faddr2line vmlinux
> reweight_entity+0x3b0/0x490
> reweight_entity+0x3b0/0x490:

Could you please try:

  https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?h=sched/urgent&id=a3b75dce9d9ae4510ea75b655567f50622f48706


---
Subject: sched/eevdf: Fix heap corruption more
From: Peter Zijlstra <peterz@infradead.org>
Date: Tue Oct 17 16:59:47 CEST 2023

Because someone is a flaming idiot... :/

Fixes: 8dafa9d0eb1a ("sched/eevdf: Fix min_deadline heap integrity")
Reported-by: 0599jiangyc@gmail.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218020
---
 kernel/sched/fair.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3699,7 +3699,8 @@ static void reweight_entity(struct cfs_r
 		 */
 		deadline = div_s64(deadline * old_weight, weight);
 		se->deadline = se->vruntime + deadline;
-		min_deadline_cb_propagate(&se->run_node, NULL);
+		if (se != cfs_rq->curr)
+			min_deadline_cb_propagate(&se->run_node, NULL);
 	}
 
 #ifdef CONFIG_SMP