From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6298EC4332E for ; Fri, 19 Mar 2021 13:30:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4898064F6C for ; Fri, 19 Mar 2021 13:30:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230134AbhCSN3n (ORCPT ); Fri, 19 Mar 2021 09:29:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229951AbhCSN3S (ORCPT ); Fri, 19 Mar 2021 09:29:18 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EE22C06175F; Fri, 19 Mar 2021 06:29:11 -0700 (PDT) Date: Fri, 19 Mar 2021 13:29:09 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1616160549; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=W8cadyBPa/8J2mo72Ftnwcgf1KBVe6QICBL0FOunmDo=; b=2sFBpEJ0upvd6oozi7Qk8wY+FzDGpNfZQ7ZYjWXFmGvrQHhVemTh4qLH/Lo11iW7rwXASn IyTwHx4pl5+bEA6IvEqJQ+DuHiNycG2KLgeROIQkFdciOai4/RsOt828uLcbMfLUOqAqTr CL597LpnhdM9lIMu0IONkmZGOSOcNB8z02oVVmjPkggn3i1iHYob7akC3QphTY6axUYubg 5tIdfs9Dxo6MAxKHmjFkluhs2QYWv+zVMo9sdIvpWIWwVRBL/PN19B82I3rWZmnAJENVqc yPb2R+n5wv1hotBvFGGu4TdH9w2bCTJVGSuFV3ix1oHVhC5MTm43hEeKNz5RxA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1616160549; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=W8cadyBPa/8J2mo72Ftnwcgf1KBVe6QICBL0FOunmDo=; b=IzSBxznkF3ybIEWChepudKcBUAyxwUDSIL1WnFSLBQLEpHAclFQ7uw44Ro5tnEwK8tR/xx r4POvsaCJpV8S1CA== From: "tip-bot2 for Lv Yunlong" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: efi/urgent] firmware/efi: Fix a use after bug in efi_mem_reserve_persistent Cc: Lv Yunlong , Ard Biesheuvel , x86@kernel.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Message-ID: <161616054920.398.5501549197969092499.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the efi/urgent branch of tip: Commit-ID: 9ceee7d0841a8f7d7644021ba7d4cc1fbc7966e3 Gitweb: https://git.kernel.org/tip/9ceee7d0841a8f7d7644021ba7d4cc1fbc7966e3 Author: Lv Yunlong AuthorDate: Wed, 10 Mar 2021 00:31:27 -08:00 Committer: Ard Biesheuvel CommitterDate: Fri, 19 Mar 2021 07:44:27 +01:00 firmware/efi: Fix a use after bug in efi_mem_reserve_persistent In the for loop in efi_mem_reserve_persistent(), prsv = rsv->next use the unmapped rsv. Use the unmapped pages will cause segment fault. Fixes: 18df7577adae6 ("efi/memreserve: deal with memreserve entries in unmapped memory") Signed-off-by: Lv Yunlong Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index df3f9bc..4b7ee3f 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -927,7 +927,7 @@ 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; prsv = rsv->next) { + for (prsv = efi_memreserve_root->next; prsv; ) { rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { @@ -937,6 +937,7 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) memunmap(rsv); return efi_mem_reserve_iomem(addr, size); } + prsv = rsv->next; memunmap(rsv); }