From patchwork Mon Aug 5 21:08:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13754069 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E6B61C3DA7F for ; Mon, 5 Aug 2024 21:11:58 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sb4xr-0002Zh-K0; Mon, 05 Aug 2024 17:09:59 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sb4xJ-0000d1-RA for qemu-devel@nongnu.org; Mon, 05 Aug 2024 17:09:25 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sb4xI-0008W2-6R for qemu-devel@nongnu.org; Mon, 05 Aug 2024 17:09:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1722892163; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=imRy/cCkdNUHP3mYUYZKXEbSa2NYjKrWcecXWJ8m3RY=; b=cVNjjo779+4NHjUTYo6lET6syufY5GhAkQ//7pY7Rszk1puZ4bhznyAmddYataq9fRB10/ vAAMq1U3PlaJ9c/7JlEGohHEoMBROf8FKA8pfZ9lV+TG6RKwHVRojesWKrkmioHc30BQqq BR+7iP/CBI95uvswHQ5UT6hrRdEup9w= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-694-1bx2gr0iPhKokF0Vph--fg-1; Mon, 05 Aug 2024 17:09:20 -0400 X-MC-Unique: 1bx2gr0iPhKokF0Vph--fg-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7EA671956046; Mon, 5 Aug 2024 21:09:19 +0000 (UTC) Received: from merkur.fritz.box (unknown [10.39.193.224]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 0F02930001AD; Mon, 5 Aug 2024 21:09:17 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [PULL 10/13] vvfat: Fix wrong checks for cluster mappings invariant Date: Mon, 5 Aug 2024 23:08:48 +0200 Message-ID: <20240805210851.314076-11-kwolf@redhat.com> In-Reply-To: <20240805210851.314076-1-kwolf@redhat.com> References: <20240805210851.314076-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.143, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Amjad Alsharafi How this `abort` was intended to check for was: - if the `mapping->first_mapping_index` is not the same as `first_mapping_index`, which **should** happen only in one case, when we are handling the first mapping, in that case `mapping->first_mapping_index == -1`, in all other cases, the other mappings after the first should have the condition `true`. - From above, we know that this is the first mapping, so if the offset is not `0`, then abort, since this is an invalid state. The issue was that `first_mapping_index` is not set if we are checking from the middle, the variable `first_mapping_index` is only set if we passed through the check `cluster_was_modified` with the first mapping, and in the same function call we checked the other mappings. One approach is to go into the loop even if `cluster_was_modified` is not true so that we will be able to set `first_mapping_index` for the first mapping, but since `first_mapping_index` is only used here, another approach is to just check manually for the `mapping->first_mapping_index != -1` since we know that this is the value for the only entry where `offset == 0` (i.e. first mapping). Signed-off-by: Amjad Alsharafi Reviewed-by: Kevin Wolf Message-ID: Signed-off-by: Kevin Wolf --- block/vvfat.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/block/vvfat.c b/block/vvfat.c index cfde468c2e..e3a83fbc88 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -1880,7 +1880,6 @@ get_cluster_count_for_direntry(BDRVVVFATState* s, direntry_t* direntry, const ch uint32_t cluster_num = begin_of_direntry(direntry); uint32_t offset = 0; - int first_mapping_index = -1; mapping_t* mapping = NULL; const char* basename2 = NULL; @@ -1942,14 +1941,9 @@ get_cluster_count_for_direntry(BDRVVVFATState* s, direntry_t* direntry, const ch if (strcmp(basename, basename2)) copy_it = 1; - first_mapping_index = array_index(&(s->mapping), mapping); - } - - if (mapping->first_mapping_index != first_mapping_index - && mapping->info.file.offset > 0) { - abort(); - copy_it = 1; } + assert(mapping->first_mapping_index == -1 + || mapping->info.file.offset > 0); /* need to write out? */ if (!was_modified && is_file(direntry)) {