diff options
Diffstat (limited to 'fs/cifs/cifssmb.c')
-rw-r--r-- | fs/cifs/cifssmb.c | 54 |
1 files changed, 25 insertions, 29 deletions
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 37113450757..675041a6949 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -331,37 +331,35 @@ smb_init_no_reconnect(int smb_command, int wct, struct cifsTconInfo *tcon, static int validate_t2(struct smb_t2_rsp *pSMB) { - int rc = -EINVAL; - int total_size; - char *pBCC; + unsigned int total_size; + + /* check for plausible wct */ + if (pSMB->hdr.WordCount < 10) + goto vt2_err; - /* check for plausible wct, bcc and t2 data and parm sizes */ /* check for parm and data offset going beyond end of smb */ - if (pSMB->hdr.WordCount >= 10) { - if ((le16_to_cpu(pSMB->t2_rsp.ParameterOffset) <= 1024) && - (le16_to_cpu(pSMB->t2_rsp.DataOffset) <= 1024)) { - /* check that bcc is at least as big as parms + data */ - /* check that bcc is less than negotiated smb buffer */ - total_size = le16_to_cpu(pSMB->t2_rsp.ParameterCount); - if (total_size < 512) { - total_size += - le16_to_cpu(pSMB->t2_rsp.DataCount); - /* BCC le converted in SendReceive */ - pBCC = (pSMB->hdr.WordCount * 2) + - sizeof(struct smb_hdr) + - (char *)pSMB; - if ((total_size <= (*(u16 *)pBCC)) && - (total_size < - CIFSMaxBufSize+MAX_CIFS_HDR_SIZE)) { - return 0; - } - } - } - } + if (get_unaligned_le16(&pSMB->t2_rsp.ParameterOffset) > 1024 || + get_unaligned_le16(&pSMB->t2_rsp.DataOffset) > 1024) + goto vt2_err; + + /* check that bcc is at least as big as parms + data */ + /* check that bcc is less than negotiated smb buffer */ + total_size = get_unaligned_le16(&pSMB->t2_rsp.ParameterCount); + if (total_size >= 512) + goto vt2_err; + + total_size += get_unaligned_le16(&pSMB->t2_rsp.DataCount); + if (total_size > get_bcc(&pSMB->hdr) || + total_size >= CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) + goto vt2_err; + + return 0; +vt2_err: cifs_dump_mem("Invalid transact2 SMB: ", (char *)pSMB, sizeof(struct smb_t2_rsp) + 16); - return rc; + return -EINVAL; } + int CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses) { @@ -452,7 +450,6 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses) server->maxBuf = min((__u32)le16_to_cpu(rsp->MaxBufSize), (__u32)CIFSMaxBufSize + MAX_CIFS_HDR_SIZE); server->max_vcs = le16_to_cpu(rsp->MaxNumberVcs); - GETU32(server->sessid) = le32_to_cpu(rsp->SessionKey); /* even though we do not use raw we might as well set this accurately, in case we ever find a need for it */ if ((le16_to_cpu(rsp->RawMode) & RAW_ENABLE) == RAW_ENABLE) { @@ -566,7 +563,6 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses) (__u32) CIFSMaxBufSize + MAX_CIFS_HDR_SIZE); server->max_rw = le32_to_cpu(pSMBr->MaxRawSize); cFYI(DBG2, "Max buf = %d", ses->server->maxBuf); - GETU32(ses->server->sessid) = le32_to_cpu(pSMBr->SessionKey); server->capabilities = le32_to_cpu(pSMBr->Capabilities); server->timeAdj = (int)(__s16)le16_to_cpu(pSMBr->ServerTimeZone); server->timeAdj *= 60; @@ -5611,7 +5607,7 @@ QAllEAsRetry: } /* make sure list_len doesn't go past end of SMB */ - end_of_smb = (char *)pByteArea(&pSMBr->hdr) + BCC(&pSMBr->hdr); + end_of_smb = (char *)pByteArea(&pSMBr->hdr) + get_bcc(&pSMBr->hdr); if ((char *)ea_response_data + list_len > end_of_smb) { cFYI(1, "EA list appears to go beyond SMB"); rc = -EIO; |