From nobody Thu Apr 2 22:23:34 2026 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 E9F3E4C97 for ; Sat, 14 Feb 2026 08:09:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771056596; cv=none; b=nFyXZsNZtZDbxb4oR2jLOph7Q2BUCb6WMDLRjSs3R7SIczu0Q6rPzdXd3ZhqJekLztiL6XgSdVizJJCrKjcPHAM406VYz3DhL7ZJ73N7qAdk3Ds4K8Ya9nyFZY1/MqMmpHJJshDiK1mvcaWJMhK0yLv4R2ohgOGqh2nLPoFuKgI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771056596; c=relaxed/simple; bh=yZJwP+nsAfnT8DMGk/jL6ONa/8beKhsUbC/4OfiH+UI=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=SQJe8kUFaJ1S6hi6Eqkq8E4A5dR1zu2VCzzDQ76Ac0Sxdny0mUbyvxT8iWshlVcrPch7Z3wGhXPfSfhM/vkeiRuwSr7IinSIMKs9m1x4fXTqqDjVzz77wzJCcqFpKoCWJPRWwF06MVtogsVw6531QE/lcNFAkQSNJ48rftScMJM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--liulynn.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=C/bgT+Au; arc=none smtp.client-ip=209.85.215.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--liulynn.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="C/bgT+Au" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-c6e18ade2c2so1142263a12.1 for ; Sat, 14 Feb 2026 00:09:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1771056594; x=1771661394; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=JJxsPsPKNTjfv6PsB/f5RXxGICW3iUFDwWM6i7w1qdo=; b=C/bgT+Au7vhgSehlvmnJRMeMmd0Ev2rVwXrT0Z31XGYSX4GgsW6Q5fWdysHQGYaYSz hd0axArblWcfQ/ZZoDDfqtienVAwuraEL9TmVo+kUzEgvsf/6OpkqhOOS4HgFivNwxQ3 meXj8DYdA72NqdwqeWaYXRH6VUIP+IdUKitIZLd813ZKIW98zMwZpyRit7yzzBy7xPTS z3SNUvkHjyxmf2H//yh0hCFceHuPV0ggkO6t8+n7peJ/njSEa8A4/MkirmDgzH/Axfrm cHYgc08NMiSq7jZUKJu4JzxX981gumkZgSr7Iq/JvOgg6XAanbmWSvtVGCZ57qAqIFKD 0XhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771056594; x=1771661394; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=JJxsPsPKNTjfv6PsB/f5RXxGICW3iUFDwWM6i7w1qdo=; b=tXbuo8qWPykwZXEan78657DB+CLGkMpH7QRRkkqIYWr+1Ko1aycRNBhCRf3MBy9rdq p74Nb8r+WJS+StDhLe9/6d5N01v6sm837IVZ/P+1upBZh90n6iabU5QxiitZaz0wPWRq sc+S8VUhA0oTaTW74f9zd78qrIWfPGl8dvmDdo5kchcNdwOH+Ji6heOAnhQY1rrJSu0t xyyUyvnrGFmiU4Mek0hd8YgTD/bzP+g4XJ/kTUpVtgjkuEG6VzQuTVfSMChz8v+es/4h CjKd55f4XFtHnjHFrSIBWZtI3XdymVdOsqcFlaH1fQ6mVyDJXLXCoG00z0+FKWcfPbHX ZciQ== X-Forwarded-Encrypted: i=1; AJvYcCUqf5rzBGStiAd0vM6gegiFRnQdWyOWfIsHX5lCYEOhwKYWy+KfloRScJ1wFIcojzUZWeu7iVwXbtAchR0=@vger.kernel.org X-Gm-Message-State: AOJu0YyM7hnaoZXFdNboPvIJo9zHGWNwVSVTNGTNT2dFRsf28xSXe0Af D3sK0G/ICm61wCGxsVniQNwDYeZG6IBSw8nzc6Q3h5kc+eaG4O39Yiz1cYIpUQWZuZdiwj+COUj 2YBEIT3xxtg== X-Received: from pgcv9.prod.google.com ([2002:a05:6a02:5309:b0:bd9:a349:94a3]) (user=liulynn job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a21:9148:b0:37e:4319:d7c9 with SMTP id adf61e73a8af0-3946c911088mr4095339637.77.1771056593999; Sat, 14 Feb 2026 00:09:53 -0800 (PST) Date: Sat, 14 Feb 2026 08:09:19 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.53.0.273.g2a3d683680-goog Message-ID: <20260214080919.390846-1-liulynn@google.com> Subject: [PATCH] iommu/iova: Add NULL check in iova_magazine_free() From: Lynn Liu To: joro@8bytes.org, will@kernel.org, robin.murphy@arm.com Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, lynn Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: lynn When iova_domain_init_rcaches() fails to allocate an iova_magazine during the initialization of per-cpu rcaches, it jumps to out_err and calls free_iova_rcaches() for cleanup. In free_iova_rcaches(), the code iterates through all possible CPUs to free both cpu_rcache->loaded and cpu_rcache->prev. However, if the original allocation failed mid-way through the CPU loop, the pointers for the remaining CPUs remain NULL. Since kmem_cache_free() does not explicitly handle NULL pointers like kfree() does, passing these NULL pointers leads to a kernel paging request fault. Add a NULL check in iova_magazine_free() to safely handle partially initialized rcaches in error paths. Signed-off-by: lynn --- drivers/iommu/iova.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 18f839721813..e026be5e068b 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -611,7 +611,8 @@ static struct iova_magazine *iova_magazine_alloc(gfp_t = flags) =20 static void iova_magazine_free(struct iova_magazine *mag) { - kmem_cache_free(iova_magazine_cache, mag); + if (mag) + kmem_cache_free(iova_magazine_cache, mag); } =20 static void --=20 2.53.0.273.g2a3d683680-goog