From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f169.google.com (mail-qk1-f169.google.com [209.85.222.169]) (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 D8E1D39D6C5 for ; Mon, 30 Mar 2026 21:10:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774905015; cv=none; b=lSkyPFaef3gxghcobWzqq8cpBpr/ern4N58zlnj84d1h1ZGhRL726JYe6yMHgY/Pa6rSbG/TC2hNrs0IbZK15/7H5+eOlrMS52aH6+gr1UDDkrs7E0e7Wlrvj6C6jr6NpY58k1+sRzZeVxc8SqLZdDbvlvGE8gvRonkewDX6CPw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774905015; c=relaxed/simple; bh=QWAIbpgsCGqgoeRq9mKxjk8QRS9utd0ORURW77Cr4f8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=meiH7ThWHantFNy0bLQpMtbSdQJAf9BZ7rQJFYHBDwkV6ngl67nP2DiQsEOxBVy12jk6VSB3X/FBunLaWQqJI3CC3I7+jkjnF8C64a0Bz2xShtVBd3+pS1bw7X+5J52wIjMat8wlYM99+4r5pfo/D/xtUYVNFPtTr/oWee77DZ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=bHDg0Okz; arc=none smtp.client-ip=209.85.222.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="bHDg0Okz" Received: by mail-qk1-f169.google.com with SMTP id af79cd13be357-8c6f21c2d81so459649785a.2 for ; Mon, 30 Mar 2026 14:10:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1774905012; x=1775509812; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=aa+fex/1gzXGVgDeRYj4FaJ5P8y3pcMc4PmRk/wiRnM=; b=bHDg0OkzySZSTtAEGvnrVTXY/7kT7gQ5cATbeEoQc/3g88JcLo92PKh4+lQzNMasnG 8xI6uULrw8nEdS8WHWPidlxNiZjB5ixAZ4AJbKWyU0fS0bsnj2d4nR298w+70lbuDnYb HWqUZfgsq/u0cB202ZRzap8ItlMqRhw4Bxt00Ps8KeUVB9tuFpOXd5nxw3vwEk3mU5oV +/yVAYc/D8An/MF9pI9nuIDJzFyekuhYIC2pSp172AKhIIYGGc/pxRrY9rRzetg4VnfR Hh5F9nlYP1wudsFtzhleYQP1X1tNg3Ok7MpePKCyuTP/zpBrGTzims1QkPmghT4Jpjgm 1aiQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774905012; x=1775509812; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=aa+fex/1gzXGVgDeRYj4FaJ5P8y3pcMc4PmRk/wiRnM=; b=HEz1lQWij/K2AGbypqMPVO9zMphqDdrYrW1slaMBz5HmrTQJV7co8pKeLSctThDmFl 3eVFQG5LJad5nAcT03MPZTw3Vj9G6BpIf2+Eu9k+Q7TYDWqlbgezy0uZDqkKwIRWiX4Y PK5in/LeHCAGO73It8w+/BaL8m+eybu3kkVmuPdX8qO2eLxxC0OqXdMs/9QRMn3wURhv gwvPOAl7suCZBQhvxKzOwZEddahmTxqWqsaJNPP56NytINDHYHm9uB53sujha0uubH/O ift+9oHaN3wFNMoR4EuTsMMX0zd9EDxl96Rw+Ae14/6bCeCuT9HxiVxLyWTOE16etXH4 bSnQ== X-Gm-Message-State: AOJu0Yy/CQqByF6Vj31uvxzNO/h8wyQjhDlnaEWBHpsPP+7jNqSAtYrU s3KT8ZYu0PHTPiI0mbH1tM4BoxwxD9U8AfsZhZT+JPcg1dlx78dJNKy8imNS+vDX X-Gm-Gg: ATEYQzxCXZW17fbm+I8HAwgYnJ6atrcm5buliT5COswBUXN5bo8FYPZ4JXf4I6qg681 Trnl5XW1NXbc4Mxl/RBYH2ipTlX9grZZwKm6tHa9E8BzthHA1/yLVGa+Fzw0lo/x4j+JwDtRkbJ hHfrPEyfWE30hBIpOLjAdM+YMaX6yIiRovtJFpNNIrX4FqHwk2tU6JmNBJhKsqBIYZrBw2VXQfM CPL/qMkYPk7pUt+Wi9z2JyEZWUEgi3NM+nhspA4im7FOiQMAWkbxEbwPjL5Uzs7RHhnt0h5jvwf eVL5F1dPz9t1EDMS3rZ0lE6jESg0X+7XpTDhl/3zGQGfqhl+qrsBDxqj1j1DHL8LBT5kFpDOwTr pge0Kzh38G7asUnP1HukEzWEGIU6x2xH7cYUBGKFHg1Nm1vOPOBi80JaM0irAD/0xAyQHnXZQOo tZN0DqHiFMQVs9AnbQefpzvdnREDg/hRb8i6zxpy3L X-Received: by 2002:a05:620a:3183:b0:8c6:ff8f:58af with SMTP id af79cd13be357-8d01c7bd490mr1854309685a.51.1774905012416; Mon, 30 Mar 2026 14:10:12 -0700 (PDT) Received: from ArchTX.mobile.psu.edu ([104.39.41.64]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8d02e697689sm598715085a.16.2026.03.30.14.10.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Mar 2026 14:10:11 -0700 (PDT) From: Dingisoul To: linux-sgx@vger.kernel.org Cc: jarkko@kernel.org, dave.hansen@linux.intel.com, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, shuangpeng.kernel@gmail.com Subject: [BUG] x86/sgx: missing kref_put() in sgx_encl_mm_add() error path Date: Mon, 30 Mar 2026 17:09:57 -0400 Message-ID: <20260330210957.839878-1-dingiso.kernel@gmail.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-sgx@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Kernel maintainers, We found a possible refcount leak in sgx_encl_mm_add(). In this function, a reference to encl->refcount is taken before registering the MMU notifier: /* Grab a refcount for the encl_mm->encl reference: */ kref_get(&encl->refcount); // 1. Reference acquired here. encl_mm->encl = encl; ret = __mmu_notifier_register(&encl_mm->mmu_notifier, mm); if (ret) { kfree(encl_mm); return ret; // 2. Returns without kref_put. } If __mmu_notifier_register() fails, the function frees encl_mm but does not drop the reference acquired by kref_get(&encl->refcount). This seems to leak one reference to encl. Please let us know if the kref_put is unnecessary here. Thanks.