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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99EEDC433EF for ; Wed, 29 Sep 2021 08:45:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 831F6613C8 for ; Wed, 29 Sep 2021 08:45:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244835AbhI2IrP (ORCPT ); Wed, 29 Sep 2021 04:47:15 -0400 Received: from mail-pj1-f45.google.com ([209.85.216.45]:37393 "EHLO mail-pj1-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244764AbhI2IrO (ORCPT ); Wed, 29 Sep 2021 04:47:14 -0400 Received: by mail-pj1-f45.google.com with SMTP id me5-20020a17090b17c500b0019af76b7bb4so3696026pjb.2 for ; Wed, 29 Sep 2021 01:45:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=bLWfFUHu0GP9lqFAtezgaEiZzcH7MQ1RUoailCDJ1cg=; b=XIIQb1wWZ2ZTctiWfwKdukmICTGHDw10c6Wb/xKrNYBycBScD3o89DDBGwCj1FoGBc Gk9onT4ZxWJ6MJb1i9JRg//kVRrJQ1Brs1zBOtYB/zRgRVN002JVldH4bsHo8fofcXJ2 OJQlakctK1kkHuoZ4AWMpNyNQ0vwxRcGxrZgYfUAktUlBaWXyCzCFIGsZIov6X2rpQUt kF8gAWv/b4zlelqeoYF18ZLxGyzkG4eVO4xQ40KQ9vFzqV1d80981RqypQOEee4Un0x9 G5UEEVaaj0cVNJtFafs1QEgOVQJoEo2uIjeQj5sjP8aHkrPRptDlNjj3A/did/Rl6Yod 0xYg== X-Gm-Message-State: AOAM532owF7HS271aPgf5Hfpl0IqMm75wmhZ8uPc22SltYbhLeJVfj8I rENETEMiJkDSsl7AboF5edf+CmDw9VqD6A== X-Google-Smtp-Source: ABdhPJws7H9sSUPWIC1wkegULQDlXGrh/U9ET6WdmfWE6JbzmG8RWHhnJRAbk4jg//XJ0ueE1FBOHw== X-Received: by 2002:a17:902:64d6:b0:13e:59fe:8124 with SMTP id y22-20020a17090264d600b0013e59fe8124mr1846970pli.89.1632905131638; Wed, 29 Sep 2021 01:45:31 -0700 (PDT) Received: from localhost.localdomain ([61.74.27.164]) by smtp.gmail.com with ESMTPSA id q3sm1912344pgf.18.2021.09.29.01.45.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Sep 2021 01:45:31 -0700 (PDT) From: Namjae Jeon To: linux-cifs@vger.kernel.org Cc: Hyunchul Lee , Ronnie Sahlberg , Steve French , Ralph Boehme , Namjae Jeon Subject: [PATCH v4 7/9] ksmbd: add buffer validation for SMB2_CREATE_CONTEXT Date: Wed, 29 Sep 2021 17:44:59 +0900 Message-Id: <20210929084501.94846-8-linkinjeon@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210929084501.94846-1-linkinjeon@kernel.org> References: <20210929084501.94846-1-linkinjeon@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org From: Hyunchul Lee Add buffer validation for SMB2_CREATE_CONTEXT. Cc: Ronnie Sahlberg Cc: Steve French Reviewed-by: Ralph Boehme Signed-off-by: Hyunchul Lee Signed-off-by: Namjae Jeon --- fs/ksmbd/oplock.c | 41 +++++++++++++++++++++++++++++++---------- fs/ksmbd/smb2pdu.c | 25 ++++++++++++++++++++++++- fs/ksmbd/smbacl.c | 21 +++++++++++++++++++-- 3 files changed, 74 insertions(+), 13 deletions(-) diff --git a/fs/ksmbd/oplock.c b/fs/ksmbd/oplock.c index 16b6236d1bd2..f9dae6ef2115 100644 --- a/fs/ksmbd/oplock.c +++ b/fs/ksmbd/oplock.c @@ -1451,26 +1451,47 @@ struct lease_ctx_info *parse_lease_state(void *open_req) */ struct create_context *smb2_find_context_vals(void *open_req, const char *tag) { - char *data_offset; struct create_context *cc; unsigned int next = 0; char *name; struct smb2_create_req *req = (struct smb2_create_req *)open_req; + unsigned int remain_len, name_off, name_len, value_off, value_len, + cc_len; - data_offset = (char *)req + 4 + le32_to_cpu(req->CreateContextsOffset); - cc = (struct create_context *)data_offset; + /* + * CreateContextsOffset and CreateContextsLength are guaranteed to + * be valid because of ksmbd_smb2_check_message(). + */ + cc = (struct create_context *)((char *)req + 4 + + le32_to_cpu(req->CreateContextsOffset)); + remain_len = le32_to_cpu(req->CreateContextsLength); do { - int val; - cc = (struct create_context *)((char *)cc + next); - name = le16_to_cpu(cc->NameOffset) + (char *)cc; - val = le16_to_cpu(cc->NameLength); - if (val < 4) + if (remain_len < offsetof(struct create_context, Buffer)) return ERR_PTR(-EINVAL); - if (memcmp(name, tag, val) == 0) - return cc; next = le32_to_cpu(cc->Next); + name_off = le16_to_cpu(cc->NameOffset); + name_len = le16_to_cpu(cc->NameLength); + value_off = le16_to_cpu(cc->DataOffset); + value_len = le32_to_cpu(cc->DataLength); + cc_len = next ? next : remain_len; + + if ((next & 0x7) != 0 || + next > remain_len || + name_off != offsetof(struct create_context, Buffer) || + name_len < 4 || + name_off + name_len > cc_len || + (value_off & 0x7) != 0 || + (value_off && (value_off < name_off + name_len)) || + ((u64)value_off + value_len > cc_len)) + return ERR_PTR(-EINVAL); + + name = (char *)cc + name_off; + if (memcmp(name, tag, name_len) == 0) + return cc; + + remain_len -= next; } while (next != 0); return NULL; diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 0b0ab3297e05..e40bcc86f3b3 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -2427,6 +2427,10 @@ static int smb2_create_sd_buffer(struct ksmbd_work *work, ksmbd_debug(SMB, "Set ACLs using SMB2_CREATE_SD_BUFFER context\n"); sd_buf = (struct create_sd_buf_req *)context; + if (le16_to_cpu(context->DataOffset) + + le32_to_cpu(context->DataLength) < + sizeof(struct create_sd_buf_req)) + return -EINVAL; return set_info_sec(work->conn, work->tcon, path, &sd_buf->ntsd, le32_to_cpu(sd_buf->ccontext.DataLength), true); } @@ -2621,6 +2625,12 @@ int smb2_open(struct ksmbd_work *work) goto err_out1; } else if (context) { ea_buf = (struct create_ea_buf_req *)context; + if (le16_to_cpu(context->DataOffset) + + le32_to_cpu(context->DataLength) < + sizeof(struct create_ea_buf_req)) { + rc = -EINVAL; + goto err_out1; + } if (req->CreateOptions & FILE_NO_EA_KNOWLEDGE_LE) { rsp->hdr.Status = STATUS_ACCESS_DENIED; rc = -EACCES; @@ -2659,6 +2669,12 @@ int smb2_open(struct ksmbd_work *work) } else if (context) { struct create_posix *posix = (struct create_posix *)context; + if (le16_to_cpu(context->DataOffset) + + le32_to_cpu(context->DataLength) < + sizeof(struct create_posix)) { + rc = -EINVAL; + goto err_out1; + } ksmbd_debug(SMB, "get posix context\n"); posix_mode = le32_to_cpu(posix->Mode); @@ -3049,9 +3065,16 @@ int smb2_open(struct ksmbd_work *work) rc = PTR_ERR(az_req); goto err_out; } else if (az_req) { - loff_t alloc_size = le64_to_cpu(az_req->AllocationSize); + loff_t alloc_size; int err; + if (le16_to_cpu(az_req->ccontext.DataOffset) + + le32_to_cpu(az_req->ccontext.DataLength) < + sizeof(struct create_alloc_size_req)) { + rc = -EINVAL; + goto err_out; + } + alloc_size = le64_to_cpu(az_req->AllocationSize); ksmbd_debug(SMB, "request smb2 create allocate size : %llu\n", alloc_size); diff --git a/fs/ksmbd/smbacl.c b/fs/ksmbd/smbacl.c index 0a95cdec8c80..bd792db32623 100644 --- a/fs/ksmbd/smbacl.c +++ b/fs/ksmbd/smbacl.c @@ -380,7 +380,7 @@ static void parse_dacl(struct user_namespace *user_ns, { int i, ret; int num_aces = 0; - int acl_size; + unsigned int acl_size; char *acl_base; struct smb_ace **ppace; struct posix_acl_entry *cf_pace, *cf_pdace; @@ -392,7 +392,7 @@ static void parse_dacl(struct user_namespace *user_ns, return; /* validate that we do not go past end of acl */ - if (end_of_acl <= (char *)pdacl || + if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) || end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { pr_err("ACL too small to parse DACL\n"); return; @@ -431,8 +431,22 @@ static void parse_dacl(struct user_namespace *user_ns, * user/group/other have no permissions */ for (i = 0; i < num_aces; ++i) { + if (end_of_acl - acl_base < acl_size) + break; + ppace[i] = (struct smb_ace *)(acl_base + acl_size); acl_base = (char *)ppace[i]; + acl_size = offsetof(struct smb_ace, sid) + + offsetof(struct smb_sid, sub_auth); + + if (end_of_acl - acl_base < acl_size || + ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || + (end_of_acl - acl_base < + acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) || + (le16_to_cpu(ppace[i]->size) < + acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth)) + break; + acl_size = le16_to_cpu(ppace[i]->size); ppace[i]->access_req = smb_map_generic_desired_access(ppace[i]->access_req); @@ -807,6 +821,9 @@ int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd, if (!pntsd) return -EIO; + if (acl_len < sizeof(struct smb_ntsd)) + return -EINVAL; + owner_sid_ptr = (struct smb_sid *)((char *)pntsd + le32_to_cpu(pntsd->osidoffset)); group_sid_ptr = (struct smb_sid *)((char *)pntsd + -- 2.25.1