diff options
Diffstat (limited to 'fs/cifs/smb2pdu.c')
| -rw-r--r-- | fs/cifs/smb2pdu.c | 120 |
1 files changed, 108 insertions, 12 deletions
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index d65270c290a..b0b260dbb19 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -375,7 +375,12 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) req->Capabilities = cpu_to_le32(ses->server->vals->req_capabilities); - memcpy(req->ClientGUID, cifs_client_guid, SMB2_CLIENT_GUID_SIZE); + /* ClientGUID must be zero for SMB2.02 dialect */ + if (ses->server->vals->protocol_id == SMB20_PROT_ID) + memset(req->ClientGUID, 0, SMB2_CLIENT_GUID_SIZE); + else + memcpy(req->ClientGUID, server->client_guid, + SMB2_CLIENT_GUID_SIZE); iov[0].iov_base = (char *)req; /* 4 for rfc1002 length field */ @@ -413,7 +418,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) /* SMB2 only has an extended negflavor */ server->negflavor = CIFS_NEGFLAVOR_EXTENDED; - server->maxBuf = le32_to_cpu(rsp->MaxTransactSize); + /* set it to the maximum buffer size value we can send with 1 credit */ + server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize), + SMB2_MAX_BUFFER_SIZE); server->max_read = le32_to_cpu(rsp->MaxReadSize); server->max_write = le32_to_cpu(rsp->MaxWriteSize); /* BB Do we need to validate the SecurityMode? */ @@ -454,6 +461,82 @@ neg_exit: return rc; } +int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) +{ + int rc = 0; + struct validate_negotiate_info_req vneg_inbuf; + struct validate_negotiate_info_rsp *pneg_rsp; + u32 rsplen; + + cifs_dbg(FYI, "validate negotiate\n"); + + /* + * validation ioctl must be signed, so no point sending this if we + * can not sign it. We could eventually change this to selectively + * sign just this, the first and only signed request on a connection. + * This is good enough for now since a user who wants better security + * would also enable signing on the mount. Having validation of + * negotiate info for signed connections helps reduce attack vectors + */ + if (tcon->ses->server->sign == false) + return 0; /* validation requires signing */ + + vneg_inbuf.Capabilities = + cpu_to_le32(tcon->ses->server->vals->req_capabilities); + memcpy(vneg_inbuf.Guid, tcon->ses->server->client_guid, + SMB2_CLIENT_GUID_SIZE); + + if (tcon->ses->sign) + vneg_inbuf.SecurityMode = + cpu_to_le16(SMB2_NEGOTIATE_SIGNING_REQUIRED); + else if (global_secflags & CIFSSEC_MAY_SIGN) + vneg_inbuf.SecurityMode = + cpu_to_le16(SMB2_NEGOTIATE_SIGNING_ENABLED); + else + vneg_inbuf.SecurityMode = 0; + + vneg_inbuf.DialectCount = cpu_to_le16(1); + vneg_inbuf.Dialects[0] = + cpu_to_le16(tcon->ses->server->vals->protocol_id); + + rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID, + FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */, + (char *)&vneg_inbuf, sizeof(struct validate_negotiate_info_req), + (char **)&pneg_rsp, &rsplen); + + if (rc != 0) { + cifs_dbg(VFS, "validate protocol negotiate failed: %d\n", rc); + return -EIO; + } + + if (rsplen != sizeof(struct validate_negotiate_info_rsp)) { + cifs_dbg(VFS, "invalid size of protocol negotiate response\n"); + return -EIO; + } + + /* check validate negotiate info response matches what we got earlier */ + if (pneg_rsp->Dialect != + cpu_to_le16(tcon->ses->server->vals->protocol_id)) + goto vneg_out; + + if (pneg_rsp->SecurityMode != cpu_to_le16(tcon->ses->server->sec_mode)) + goto vneg_out; + + /* do not validate server guid because not saved at negprot time yet */ + + if ((le32_to_cpu(pneg_rsp->Capabilities) | SMB2_NT_FIND | + SMB2_LARGE_FILES) != tcon->ses->server->capabilities) + goto vneg_out; + + /* validate negotiate successful */ + cifs_dbg(FYI, "validate negotiate info successful\n"); + return 0; + +vneg_out: + cifs_dbg(VFS, "protocol revalidation - security settings mismatch\n"); + return -EIO; +} + int SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses, const struct nls_table *nls_cp) @@ -829,6 +912,8 @@ SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree, ((tcon->share_flags & SHI1005_FLAGS_DFS) == 0)) cifs_dbg(VFS, "DFS capability contradicts DFS flag\n"); init_copy_chunk_defaults(tcon); + if (tcon->ses->server->ops->validate_negotiate) + rc = tcon->ses->server->ops->validate_negotiate(xid, tcon); tcon_exit: free_rsp_buf(resp_buftype, rsp); kfree(unc_path); @@ -887,6 +972,7 @@ create_durable_buf(void) buf->ccontext.NameOffset = cpu_to_le16(offsetof (struct create_durable, Name)); buf->ccontext.NameLength = cpu_to_le16(4); + /* SMB2_CREATE_DURABLE_HANDLE_REQUEST is "DHnQ" */ buf->Name[0] = 'D'; buf->Name[1] = 'H'; buf->Name[2] = 'n'; @@ -911,6 +997,7 @@ create_reconnect_durable_buf(struct cifs_fid *fid) buf->ccontext.NameLength = cpu_to_le16(4); buf->Data.Fid.PersistentFileId = fid->persistent_fid; buf->Data.Fid.VolatileFileId = fid->volatile_fid; + /* SMB2_CREATE_DURABLE_HANDLE_RECONNECT is "DHnC" */ buf->Name[0] = 'D'; buf->Name[1] = 'H'; buf->Name[2] = 'n'; @@ -1010,6 +1097,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, int rc = 0; unsigned int num_iovecs = 2; __u32 file_attributes = 0; + char *dhc_buf = NULL, *lc_buf = NULL; cifs_dbg(FYI, "create/open\n"); @@ -1076,6 +1164,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, kfree(copy_path); return rc; } + lc_buf = iov[num_iovecs-1].iov_base; } if (*oplock == SMB2_OPLOCK_LEVEL_BATCH) { @@ -1090,9 +1179,10 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, if (rc) { cifs_small_buf_release(req); kfree(copy_path); - kfree(iov[num_iovecs-1].iov_base); + kfree(lc_buf); return rc; } + dhc_buf = iov[num_iovecs-1].iov_base; } rc = SendReceive2(xid, ses, iov, num_iovecs, &resp_buftype, 0); @@ -1124,6 +1214,8 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, *oplock = rsp->OplockLevel; creat_exit: kfree(copy_path); + kfree(lc_buf); + kfree(dhc_buf); free_rsp_buf(resp_buftype, rsp); return rc; } @@ -1214,10 +1306,17 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid, rc = SendReceive2(xid, ses, iov, num_iovecs, &resp_buftype, 0); rsp = (struct smb2_ioctl_rsp *)iov[0].iov_base; - if (rc != 0) { + if ((rc != 0) && (rc != -EINVAL)) { if (tcon) cifs_stats_fail_inc(tcon, SMB2_IOCTL_HE); goto ioctl_exit; + } else if (rc == -EINVAL) { + if ((opcode != FSCTL_SRV_COPYCHUNK_WRITE) && + (opcode != FSCTL_SRV_COPYCHUNK)) { + if (tcon) + cifs_stats_fail_inc(tcon, SMB2_IOCTL_HE); + goto ioctl_exit; + } } /* check if caller wants to look at return data or just return rc */ @@ -1266,7 +1365,6 @@ SMB2_set_compression(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid, u64 volatile_fid) { int rc; - char *res_key = NULL; struct compress_ioctl fsctl_input; char *ret_data = NULL; @@ -1279,7 +1377,6 @@ SMB2_set_compression(const unsigned int xid, struct cifs_tcon *tcon, 2 /* in data len */, &ret_data /* out data */, NULL); cifs_dbg(FYI, "set compression rc %d\n", rc); - kfree(res_key); return rc; } @@ -1806,7 +1903,8 @@ smb2_writev_callback(struct mid_q_entry *mid) /* smb2_async_writev - send an async write, and set up mid to handle result */ int -smb2_async_writev(struct cifs_writedata *wdata) +smb2_async_writev(struct cifs_writedata *wdata, + void (*release)(struct kref *kref)) { int rc = -EACCES; struct smb2_write_req *req = NULL; @@ -1854,7 +1952,7 @@ smb2_async_writev(struct cifs_writedata *wdata) smb2_writev_callback, wdata, 0); if (rc) { - kref_put(&wdata->refcount, cifs_writedata_release); + kref_put(&wdata->refcount, release); cifs_stats_fail_inc(tcon, SMB2_WRITE_HE); } @@ -2154,11 +2252,9 @@ send_set_info(const unsigned int xid, struct cifs_tcon *tcon, rc = SendReceive2(xid, ses, iov, num, &resp_buftype, 0); rsp = (struct smb2_set_info_rsp *)iov[0].iov_base; - if (rc != 0) { + if (rc != 0) cifs_stats_fail_inc(tcon, SMB2_SET_INFO_HE); - goto out; - } -out: + free_rsp_buf(resp_buftype, rsp); kfree(iov); return rc; |
