From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-44.mta1.migadu.com [95.215.58.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DBDE73C9438 for ; Sun, 27 Sep 2026 07:53:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790495590; cv=none; b=gngJoRZ4BkutQQF8WdfLM5/ELzm7VvBRFSjHu9yl44RKW/Kw2iq/MCa7pemExNQ3gQSBGSxOG1LaeTc7urv8G20AmJ9wNGhKIqAww5B0AFwypZctlVrqxvRQim7/yKUeA+1X19Tx7a/15w/2LZGUwjTRyEZf1QHRfqAgvAklyFg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790495590; c=relaxed/simple; bh=m/X5aoPRXyHsasyxwDbYK+y0ZJ9VoSZaZZKIVhLMmTw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GYcIqXA6M3l1Vrx+ybb0q2QaFEMepHmxtEX+Q15IPN6/FwJsnKdeia/97JMOu5+rcf/gZ7maLpvyVNkgsYi9ar3ytiXFKOZLJgSK2n51CKS59LPxSrW80us//ZzENEFPVYYlJqurNFf0SLANEFwEcGJHUXXF1XIFBaXi8w6sv0g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Vywe1/s6; arc=none smtp.client-ip=95.215.58.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Vywe1/s6" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=m/X5aoPRXyHsasyxwDbYK+y0ZJ9VoSZaZZKIVhLMmTw=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790495583; v=1; x=1791100383; b=Vywe1/s672i3zZ9ozFKDxbu5cqMajZrQEdnCzh3PgyfAsgo6MqlLYmn9ZiOoLZA18ExCo+Xk P3lPRXia/9KAJieAq346J57fYd4kOm/ww8MyaD5gPwxvu1coNpJnkyhN21oKTVTS/ol/vn1dwgV SE6pChfCxhphaM5aIroXNkKc= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 5472bcec4e8a13a7; Sun, 27 Sep 2026 07:53:03 +0000 X-Mizu-Trace-ID: 5472bcec4e8a13a7 X-Migadu-Flow: FLOW_OUT From: Tao Cui To: maobibo@loongson.cn, gaosong@loongson.cn, zhaotianrui@loongson.cn Cc: loongarch@lists.linux.dev, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, chenhuacai@kernel.org, kernel@xen0n.name, nagachaithanya9911@gmail.com, cui.tao@linux.dev, Tao Cui Subject: [PATCH 1/6] LoongArch: KVM: Clear device pointer in irqchip destroy callbacks Date: Sun, 27 Sep 2026 15:52:35 +0800 Message-ID: <20260927075240.3007947-2-cui.tao@linux.dev> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260927075240.3007947-1-cui.tao@linux.dev> References: <20260927075240.3007947-1-cui.tao@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tao Cui The destroy callbacks of the four irqchip devices free the device structure without clearing kvm->arch.{ipi,eiointc,pch_pic,dmsintc}, leaving a dangling pointer. ops->destroy() is not only called at VM teardown but also when KVM_CREATE_DEVICE succeeds and the following anon_inode_getfd() fails (e.g. under RLIMIT_NOFILE); the VM stays alive, kvm_arch_irqchip_in_kernel() still reports true, and interrupt injection dereferences the freed device. Clear the pointer before freeing. Fixes: c532de5a67a7 ("LoongArch: KVM: Add IPI device support") Fixes: 2e8b9df82631 ("LoongArch: KVM: Add EIOINTC device support") Fixes: e785dfacf7e7 ("LoongArch: KVM: Add PCHPIC device support") Fixes: 229132c309d6 ("LoongArch: KVM: Add DMSINTC device support") Signed-off-by: Tao Cui --- arch/loongarch/kvm/intc/dmsintc.c | 5 ++++- arch/loongarch/kvm/intc/eiointc.c | 1 + arch/loongarch/kvm/intc/ipi.c | 1 + arch/loongarch/kvm/intc/pch_pic.c | 1 + 4 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/loongarch/kvm/intc/dmsintc.c b/arch/loongarch/kvm/intc/dmsintc.c index 89f980d867be..63072595c01b 100644 --- a/arch/loongarch/kvm/intc/dmsintc.c +++ b/arch/loongarch/kvm/intc/dmsintc.c @@ -161,11 +161,14 @@ static int kvm_dmsintc_create(struct kvm_device *dev, u32 type) static void kvm_dmsintc_destroy(struct kvm_device *dev) { + struct loongarch_dmsintc *s; if (!dev || !dev->kvm || !dev->kvm->arch.dmsintc) return; - kfree(dev->kvm->arch.dmsintc); + s = dev->kvm->arch.dmsintc; + dev->kvm->arch.dmsintc = NULL; + kfree(s); kfree(dev); } diff --git a/arch/loongarch/kvm/intc/eiointc.c b/arch/loongarch/kvm/intc/eiointc.c index 80f78e07c74a..fe0a1918f26f 100644 --- a/arch/loongarch/kvm/intc/eiointc.c +++ b/arch/loongarch/kvm/intc/eiointc.c @@ -675,6 +675,7 @@ static void kvm_eiointc_destroy(struct kvm_device *dev) kvm = dev->kvm; eiointc = kvm->arch.eiointc; + kvm->arch.eiointc = NULL; mutex_lock(&kvm->slots_lock); kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &eiointc->device); kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &eiointc->device_vext); diff --git a/arch/loongarch/kvm/intc/ipi.c b/arch/loongarch/kvm/intc/ipi.c index 7b333a4a0430..6ee90c10827a 100644 --- a/arch/loongarch/kvm/intc/ipi.c +++ b/arch/loongarch/kvm/intc/ipi.c @@ -444,6 +444,7 @@ static void kvm_ipi_destroy(struct kvm_device *dev) kvm = dev->kvm; ipi = kvm->arch.ipi; + kvm->arch.ipi = NULL; mutex_lock(&kvm->slots_lock); kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &ipi->device); mutex_unlock(&kvm->slots_lock); diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c index 2b63b0c2c7ce..62c09b5f3937 100644 --- a/arch/loongarch/kvm/intc/pch_pic.c +++ b/arch/loongarch/kvm/intc/pch_pic.c @@ -483,6 +483,7 @@ static void kvm_pch_pic_destroy(struct kvm_device *dev) kvm = dev->kvm; s = kvm->arch.pch_pic; + kvm->arch.pch_pic = NULL; /* unregister pch pic device and free it's memory */ mutex_lock(&kvm->slots_lock); kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &s->device); -- 2.43.0