From patchwork Fri Feb 3 14:11:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Gusev X-Patchwork-Id: 650701 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D156C05027 for ; Fri, 3 Feb 2023 14:14:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233719AbjBCOOC (ORCPT ); Fri, 3 Feb 2023 09:14:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230309AbjBCON3 (ORCPT ); Fri, 3 Feb 2023 09:13:29 -0500 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 361DB1024B; Fri, 3 Feb 2023 06:12:55 -0800 (PST) Received: from localhost.179.lan (unknown [94.29.124.73]) by mail.ispras.ru (Postfix) with ESMTPSA id 9AEA540737BC; Fri, 3 Feb 2023 14:12:53 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 9AEA540737BC DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1675433573; bh=fmtJBEhqbrQnl44SbeJjGLinHNhS7H1mBHfFyaqD6rk=; h=From:To:Cc:Subject:Date:From; b=TEcBQP+7Kit33vGhpoDmcFGlCBxiAKrHhjP7MdFcsz23tvIZ3S6HlDv98zLLPl4O+ p/41e71xzAt9g3yck4w0kEf5qcG+AoHshZoZGidM/FpHwWsQ8Hi4qaJLUjlup1Bu8S wrxAT37NR8bpZ4ESNGVVrQMMa7GcsP3DBWFZc134= From: Anton Gusev To: Ard Biesheuvel Cc: Anton Gusev , Jonathan Richardson , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org Subject: [PATCH v2] efi: fix potential NULL deref in efi_mem_reserve_persistent Date: Fri, 3 Feb 2023 17:11:36 +0300 Message-Id: <20230203141136.14881-1-aagusev@ispras.ru> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org When iterating on a linked list, a result of memremap is dereferenced without checking it for NULL. This patch adds a check that returns -ENOMEM if it's NULL. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 18df7577adae ("efi/memreserve: deal with memreserve entries in unmapped memory") Signed-off-by: Anton Gusev --- drivers/firmware/efi/efi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index a2b0cbc8741c..1e0b016fdc2b 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -1007,6 +1007,8 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) /* first try to find a slot in an existing linked list entry */ for (prsv = efi_memreserve_root->next; prsv; ) { rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); + if (!rsv) + return -ENOMEM; index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { rsv->entry[index].base = addr;