From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp153-163.sina.com.cn (smtp153-163.sina.com.cn [61.135.153.163]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F8B8248F7C for ; Tue, 10 Feb 2026 22:52:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=61.135.153.163 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770763935; cv=none; b=ciMljsN4Jd4YaFYN1nBbexHtvN2QYaUdnfJyCGBYDeWQLQPdu1oC75lHcyD04SLU/9+tJVulY5Uj8UsPfYiUf8yq9EVtaqqeDMvSn2y5Of1oe11/iW2jiHiMRh1eU547dEF3+d7VpKQhUv49Qt45sVHm71JljW656uqRvHexRRU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770763935; c=relaxed/simple; bh=ytBMFQA6SZfDAfTsVtGeBExacqefuH0RUlqmo9jYloQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XOnxgoqHIKzZQiZuUBq9ld6EFODXh4S+9sjv5YIHFG0aZWQZz6p7W1Lijpcys8WcJWvsxug7KOi2PsVlnZcgwjGUzgE8KBs+wW8nduS5hDZTuBPQk1sNOmR3nFEZ7BlTj49WVxURLEXXUMGSSsou/iiqJ2WkQdl4x0Zk8y+ASyg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=xzIPnfD7; arc=none smtp.client-ip=61.135.153.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="xzIPnfD7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1770763929; bh=Y7gsduCslo2rcgCUIf6oEbXmz1kBsZ3M45n+WVVKhMA=; h=From:Subject:Date:Message-ID; b=xzIPnfD7P/+87XMbW9QcCc4J61J+WR0+09YFh+Zh8K1CfikV1vwBlWL1imuIgHz4C /Iu9wxguqSAgM6VZHHcIZprmImz+lBbT6eiPZ2wlFD2c4Qhm2s3kPKNwxHoniWgZFu fjZBZdrJrYfLC0B79O4W9p4Nt4n/PZk8hlpp/+no= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.62.144]) by sina.com (10.54.253.32) with ESMTP id 698BB69200007ADF; Tue, 11 Feb 2026 06:52:05 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 9076924456769 X-SMAIL-UIID: 11F9260978B343BFACF964891E61E131-20260211-065205-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [kernel?] KASAN: slab-use-after-free Read in futex_unqueue Date: Wed, 11 Feb 2026 06:51:20 +0800 Message-ID: <20260210225152.2795-1-hdanton@sina.com> In-Reply-To: <698ba684.a70a0220.2c38d7.007c.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Tue, 10 Feb 2026 13:43:32 -0800 [thread overview] > Hello, > > syzbot found the following issue on: > > HEAD commit: 72c395024dac Merge tag 'docs-7.0' of git://git.kernel.org/.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=137d9b22580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=bf83be18dae53c93 > dashboard link: https://syzkaller.appspot.com/bug?extid=6c1861115b4253e45969 > compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=169f8ae6580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f657fa580000 #syz test --- x/kernel/futex/core.c +++ y/kernel/futex/core.c @@ -1735,8 +1735,7 @@ void futex_hash_free(struct mm_struct *m free_percpu(mm->futex_ref); kvfree(mm->futex_phash_new); fph = rcu_dereference_raw(mm->futex_phash); - if (fph) - kvfree(fph); + kvfree_rcu(fph, rcu); } static bool futex_pivot_pending(struct mm_struct *mm) --