From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C7A6E38B15E; Tue, 28 Apr 2026 23:33:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777419227; cv=none; b=bLC8zUmtMP9c9SSFvpNVgbKihIMgR3AEifZYgO/HgiGOYx51QTDnMbTUZI3LvvkrBNhbP955GN2J6X/kxnjtgrsiX1C+uoaSvTFgYXdmjutaBHz+lruPSEgCDr91xWrjJ9i+l7oXRjqUNs+prlDr5dU9P/pJyR8GA2f9AfXFOMA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777419227; c=relaxed/simple; bh=tQN6MWf/5YWMmuXTo+JR3VXnNeV3GXdK1CV+HEyv1Sw=; h=Date:Message-ID:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=K7AOzKoNPpQnwKwvkSOOklx2gwrKDTp2iJaqAScTmxMALb0YDEvYE5yO2yVFiTeuMPfoPYcHt6lcrTWOWu1CjL63WdjNzYLCIld8JPhi2t/+WiRmLPIxp3vQOYl0nAM0wVWHIWgn/MzkwDE5/rLmtk12Qe4ibBqYVbLWyFD65WQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rcAO8V9M; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rcAO8V9M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D8A4C2BCAF; Tue, 28 Apr 2026 23:33:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777419227; bh=tQN6MWf/5YWMmuXTo+JR3VXnNeV3GXdK1CV+HEyv1Sw=; h=Date:From:To:Cc:Subject:References:From; b=rcAO8V9M6pHxogbzH/vEAUnm9iBn4dhcb3Qh27EtC2mnGV3PA+2AxS+FGbGa6YG92 GJqSPzRFJZifw4s56LTPGSMu8cDDZfeZePXfFxBH60Gr+UtZeDMSGenBO0l3IzIRHu ePnVt6q73yU2nXxZKkRTesQfM5vLuau3qv1Kn0QSGkspzyCoYVcD7OgmlfbFARju7x pIZL81DIiogyx+0Ej9yGY5RKA9qxYQHlzwUTdBNK58KzVstr1E4cHBljXHNtn3L6bz EAwK9DLBxhebYmf9PQ2x27fnWDGTPmb7Dwf0VtdzNXRDfAceO3gX4FdHls8Oz8iKp9 +nFRL3/atVvCw== Date: Wed, 29 Apr 2026 01:33:43 +0200 Message-ID: <20260428224427.353887714@kernel.org> User-Agent: quilt/0.68 From: Thomas Gleixner To: LKML Cc: Mathias Stearn , Dmitry Vyukov , Peter Zijlstra , linux-man@vger.kernel.org, Mark Rutland , Mathieu Desnoyers , Chris Kennelly , regressions@lists.linux.dev, Ingo Molnar , Blake Oler , Florian Weimer , Rich Felker , Matthew Wilcox , Greg Kroah-Hartman , Linus Torvalds Subject: [patch 02/10] rseq: Protect rseq_reset() against interrupts References: <20260428221058.149538293@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 rseq_reset() uses memset() to clear the tasks rseq data. That's racy against membarrier() and preemption. Guard it with irqsave to cure this. Fixes: faba9d250eae ("rseq: Introduce struct rseq_data") Reported-by: Dmitry Vyukov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org --- include/linux/rseq.h | 1 + 1 file changed, 1 insertion(+) --- a/include/linux/rseq.h +++ b/include/linux/rseq.h @@ -119,6 +119,7 @@ static inline void rseq_virt_userspace_e static inline void rseq_reset(struct task_struct *t) { + guard(irqsave)(); memset(&t->rseq, 0, sizeof(t->rseq)); t->rseq.ids.cpu_id = RSEQ_CPU_ID_UNINITIALIZED; }