diff options
-rw-r--r-- | fs/cifs/connect.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 4bc862a80ef..8b75a8ec90b 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -274,7 +274,8 @@ static int coalesce_t2(struct smb_hdr *psecond, struct smb_hdr *pTargetSMB) char *data_area_of_target; char *data_area_of_buf2; int remaining; - __u16 byte_count, total_data_size, total_in_buf, total_in_buf2; + unsigned int byte_count, total_in_buf; + __u16 total_data_size, total_in_buf2; total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount); @@ -287,7 +288,7 @@ static int coalesce_t2(struct smb_hdr *psecond, struct smb_hdr *pTargetSMB) remaining = total_data_size - total_in_buf; if (remaining < 0) - return -EINVAL; + return -EPROTO; if (remaining == 0) /* nothing to do, ignore */ return 0; @@ -308,20 +309,29 @@ static int coalesce_t2(struct smb_hdr *psecond, struct smb_hdr *pTargetSMB) data_area_of_target += total_in_buf; /* copy second buffer into end of first buffer */ - memcpy(data_area_of_target, data_area_of_buf2, total_in_buf2); total_in_buf += total_in_buf2; + /* is the result too big for the field? */ + if (total_in_buf > USHRT_MAX) + return -EPROTO; put_unaligned_le16(total_in_buf, &pSMBt->t2_rsp.DataCount); + + /* fix up the BCC */ byte_count = get_bcc_le(pTargetSMB); byte_count += total_in_buf2; + /* is the result too big for the field? */ + if (byte_count > USHRT_MAX) + return -EPROTO; put_bcc_le(byte_count, pTargetSMB); byte_count = pTargetSMB->smb_buf_length; byte_count += total_in_buf2; - - /* BB also add check that we are not beyond maximum buffer size */ - + /* don't allow buffer to overflow */ + if (byte_count > CIFSMaxBufSize) + return -ENOBUFS; pTargetSMB->smb_buf_length = byte_count; + memcpy(data_area_of_target, data_area_of_buf2, total_in_buf2); + if (remaining == total_in_buf2) { cFYI(1, "found the last secondary response"); return 0; /* we are done */ |