From patchwork Thu Aug 30 15:47:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liam Merwick X-Patchwork-Id: 10582185 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F1BCB14BD for ; Thu, 30 Aug 2018 15:56:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E19A42C0EA for ; Thu, 30 Aug 2018 15:56:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D63282C0EC; Thu, 30 Aug 2018 15:56:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 33A002C0EA for ; Thu, 30 Aug 2018 15:56:49 +0000 (UTC) Received: from localhost ([::1]:49615 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fvPJQ-0006Qq-7W for patchwork-qemu-devel@patchwork.kernel.org; Thu, 30 Aug 2018 11:56:48 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54805) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fvPCN-0006qH-VL for qemu-devel@nongnu.org; Thu, 30 Aug 2018 11:49:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fvP8Y-0005R0-3Q for qemu-devel@nongnu.org; Thu, 30 Aug 2018 11:45:37 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:44584) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fvP8X-0005QX-RT for qemu-devel@nongnu.org; Thu, 30 Aug 2018 11:45:33 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w7UFdGU6030721 for ; Thu, 30 Aug 2018 15:45:33 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=y/iXqS2mgXQufQSoaTle9V2E2l5V2Czhnww5kswlI9A=; b=eI9DCzfj6vT65DDY8jNDxn0z0M0frBRSoAbgw4z0pEp1PvylWsmIaEh7EnmyFCCx8awi fsE5HMJKo5jKckGrs7coctxpKLBbGR2kkfoNnLPGkhudNHXvvfMyvANWL8It+uHyDNVX kSQ69VDyDgr3qz4jZCaHuPKh15+B9KoANu3LVLCk4OjZINDRQdIiGUJF7+KQSE4ub6d1 EVOdSv6fFqcQHgw0yOfj/6agTKHaBENeX+vHcgcoCCusIH+xx2PPG951hIvvlaLIiSxg c7v0WBUMHYCe0UJ4Jws8VJCcZznOqqwjGJ+hQdfYp2UUFBcE4pnF2BCTOZPlwMJuit/D qg== Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by aserp2120.oracle.com with ESMTP id 2m2y2pwhhv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Thu, 30 Aug 2018 15:45:32 +0000 Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w7UFjWLW014069 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Thu, 30 Aug 2018 15:45:32 GMT Received: from abhmp0014.oracle.com (abhmp0014.oracle.com [141.146.116.20]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w7UFjWL2020756 for ; Thu, 30 Aug 2018 15:45:32 GMT Received: from ol7.uk.oracle.com (/10.175.215.81) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 30 Aug 2018 08:45:32 -0700 From: Liam Merwick To: qemu-devel@nongnu.org Date: Thu, 30 Aug 2018 16:47:08 +0100 Message-Id: <1535644031-848-6-git-send-email-Liam.Merwick@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1535644031-848-1-git-send-email-Liam.Merwick@oracle.com> References: <1535644031-848-1-git-send-email-Liam.Merwick@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9000 signatures=668708 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=4 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=750 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1808300162 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 141.146.126.78 Subject: [Qemu-devel] [PATCH 5/8] block: Fix potential Null pointer dereferences in vvfat.c X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The calls to bdrv_new_open_driver(), find_mapping_for_cluster(), and array_get_next() may return NULL but it isn't always checked for before dereferencing the value returned. Signed-off-by: Liam Merwick Reviewed-by: Darren Kenny Reviewed-by: Mark Kanda --- block/vvfat.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/block/vvfat.c b/block/vvfat.c index fc41841a5c3c..0f1f10a2f94b 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -448,6 +448,9 @@ static direntry_t *create_long_filename(BDRVVVFATState *s, const char *filename) for(i=0;idirectory)); + if (entry == NULL) { + continue; + } entry->attributes=0xf; entry->reserved[0]=0; entry->begin=0; @@ -665,6 +668,9 @@ static inline void fat_set(BDRVVVFATState* s,unsigned int cluster,uint32_t value } else { int offset = (cluster*3/2); unsigned char* p = array_get(&(s->fat), offset); + if (p == NULL) { + return; + } switch (cluster&1) { case 0: p[0] = value&0xff; @@ -730,6 +736,9 @@ static inline direntry_t* create_short_and_long_name(BDRVVVFATState* s, if(is_dot) { entry=array_get_next(&(s->directory)); + if (entry == NULL) { + return NULL; + } memset(entry->name, 0x20, sizeof(entry->name)); memcpy(entry->name,filename,strlen(filename)); return entry; @@ -844,6 +853,12 @@ static int read_directory(BDRVVVFATState* s, int mapping_index) /* create mapping for this file */ if(!is_dot && !is_dotdot && (S_ISDIR(st.st_mode) || st.st_size)) { s->current_mapping = array_get_next(&(s->mapping)); + if (s->current_mapping == NULL) { + fprintf(stderr, "Failed to create mapping for file\n"); + g_free(buffer); + closedir(dir); + return -2; + } s->current_mapping->begin=0; s->current_mapping->end=st.st_size; /* @@ -941,6 +956,9 @@ static int init_directories(BDRVVVFATState* s, /* add volume label */ { direntry_t* entry=array_get_next(&(s->directory)); + if (entry == NULL) { + return -1; + } entry->attributes=0x28; /* archive | volume label */ memcpy(entry->name, s->volume_label, sizeof(entry->name)); } @@ -953,6 +971,9 @@ static int init_directories(BDRVVVFATState* s, s->cluster_count=sector2cluster(s, s->sector_count); mapping = array_get_next(&(s->mapping)); + if (mapping == NULL) { + return -1; + } mapping->begin = 0; mapping->dir_index = 0; mapping->info.dir.parent_mapping_index = -1; @@ -1630,6 +1651,9 @@ static void schedule_rename(BDRVVVFATState* s, uint32_t cluster, char* new_path) { commit_t* commit = array_get_next(&(s->commits)); + if (commit == NULL) { + return; + } commit->path = new_path; commit->param.rename.cluster = cluster; commit->action = ACTION_RENAME; @@ -1639,6 +1663,9 @@ static void schedule_writeout(BDRVVVFATState* s, int dir_index, uint32_t modified_offset) { commit_t* commit = array_get_next(&(s->commits)); + if (commit == NULL) { + return; + } commit->path = NULL; commit->param.writeout.dir_index = dir_index; commit->param.writeout.modified_offset = modified_offset; @@ -1649,6 +1676,9 @@ static void schedule_new_file(BDRVVVFATState* s, char* path, uint32_t first_cluster) { commit_t* commit = array_get_next(&(s->commits)); + if (commit == NULL) { + return; + } commit->path = path; commit->param.new_file.first_cluster = first_cluster; commit->action = ACTION_NEW_FILE; @@ -1657,6 +1687,9 @@ static void schedule_new_file(BDRVVVFATState* s, static void schedule_mkdir(BDRVVVFATState* s, uint32_t cluster, char* path) { commit_t* commit = array_get_next(&(s->commits)); + if (commit == NULL) { + return; + } commit->path = path; commit->param.mkdir.cluster = cluster; commit->action = ACTION_MKDIR; @@ -2261,6 +2294,9 @@ static mapping_t* insert_mapping(BDRVVVFATState* s, } if (index >= s->mapping.next || mapping->begin > begin) { mapping = array_insert(&(s->mapping), index, 1); + if (mapping == NULL) { + return NULL; + } mapping->path = NULL; adjust_mapping_indices(s, index, +1); } @@ -2428,6 +2464,9 @@ static int commit_direntries(BDRVVVFATState* s, direntry_t* direntry = array_get(&(s->directory), dir_index); uint32_t first_cluster = dir_index == 0 ? 0 : begin_of_direntry(direntry); mapping_t* mapping = find_mapping_for_cluster(s, first_cluster); + if (mapping == NULL) { + return -1; + } int factor = 0x10 * s->sectors_per_cluster; int old_cluster_count, new_cluster_count; @@ -2494,6 +2533,9 @@ DLOG(fprintf(stderr, "commit_direntries for %s, parent_mapping_index %d\n", mapp direntry = array_get(&(s->directory), first_dir_index + i); if (is_directory(direntry) && !is_dot(direntry)) { mapping = find_mapping_for_cluster(s, first_cluster); + if (mapping == NULL) { + return -1; + } assert(mapping->mode & MODE_DIRECTORY); ret = commit_direntries(s, first_dir_index + i, array_index(&(s->mapping), mapping)); @@ -2522,6 +2564,10 @@ static int commit_one_file(BDRVVVFATState* s, assert(offset < size); assert((offset % s->cluster_size) == 0); + if (mapping == NULL) { + return -1; + } + for (i = s->cluster_size; i < offset; i += s->cluster_size) c = modified_fat_get(s, c); @@ -2668,6 +2714,9 @@ static int handle_renames_and_mkdirs(BDRVVVFATState* s) if (commit->action == ACTION_RENAME) { mapping_t* mapping = find_mapping_for_cluster(s, commit->param.rename.cluster); + if (mapping == NULL) { + return -1; + } char* old_path = mapping->path; assert(commit->path); @@ -2692,6 +2741,9 @@ static int handle_renames_and_mkdirs(BDRVVVFATState* s) if (is_file(d) || (is_directory(d) && !is_dot(d))) { mapping_t* m = find_mapping_for_cluster(s, begin_of_direntry(d)); + if (m == NULL) { + return -3; + } int l = strlen(m->path); char* new_path = g_malloc(l + diff + 1); @@ -3193,6 +3245,10 @@ static int enable_write_target(BlockDriverState *bs, Error **errp) backing = bdrv_new_open_driver(&vvfat_write_target, NULL, BDRV_O_ALLOW_RDWR, &error_abort); + if (!backing) { + ret = -EINVAL; + goto err; + } *(void**) backing->opaque = s; bdrv_set_backing_hd(s->bs, backing, &error_abort);