diff options
| author | Steve French <sfrench@us.ibm.com> | 2006-10-12 17:49:24 +0000 |
|---|---|---|
| committer | Steve French <sfrench@us.ibm.com> | 2006-10-12 17:49:24 +0000 |
| commit | d103e164bee2f21d0efe7d713cbbb0a443ba480d (patch) | |
| tree | 88e1d33b0a247535b181ac5bbb65514a6cc63bd0 /fs | |
| parent | 230a03950ecd63bc613c6adeffbe9049189d9f05 (diff) | |
[CIFS] Workaround incomplete byte length returned by some
servers on small SMB responses
Signed-off-by: Steve French <sfrench@us.ibm.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/cifsproto.h | 2 | ||||
| -rw-r--r-- | fs/cifs/misc.c | 42 |
2 files changed, 30 insertions, 14 deletions
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 4a4fd2dbca6..f1f8225102f 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -55,7 +55,7 @@ extern int SendReceiveBlockingLock(const unsigned int /* xid */ , struct smb_hdr * /* input */ , struct smb_hdr * /* out */ , int * /* bytes returned */); -extern int checkSMB(struct smb_hdr *smb, __u16 mid, int length); +extern int checkSMB(struct smb_hdr *smb, __u16 mid, unsigned int length); extern int is_valid_oplock_break(struct smb_hdr *smb, struct TCP_Server_Info *); extern int is_size_safe_to_change(struct cifsInodeInfo *); extern struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *); diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c index ca6e9b1413f..bbc9cd34b6e 100644 --- a/fs/cifs/misc.c +++ b/fs/cifs/misc.c @@ -418,26 +418,42 @@ checkSMBhdr(struct smb_hdr *smb, __u16 mid) } int -checkSMB(struct smb_hdr *smb, __u16 mid, int length) +checkSMB(struct smb_hdr *smb, __u16 mid, unsigned int length) { __u32 len = smb->smb_buf_length; __u32 clc_len; /* calculated length */ cFYI(0, ("checkSMB Length: 0x%x, smb_buf_length: 0x%x", length, len)); - if (((unsigned int)length < 2 + sizeof (struct smb_hdr)) || - (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)) { - if ((unsigned int)length < 2 + sizeof (struct smb_hdr)) { - if (((unsigned int)length >= - sizeof (struct smb_hdr) - 1) + + if (length < 2 + sizeof (struct smb_hdr)) { + if ((length >= sizeof (struct smb_hdr) - 1) && (smb->Status.CifsError != 0)) { - smb->WordCount = 0; - /* some error cases do not return wct and bcc */ + smb->WordCount = 0; + /* some error cases do not return wct and bcc */ + return 0; + } else if ((length == sizeof(struct smb_hdr) + 1) && + (smb->WordCount == 0)) { + char * tmp = (char *)smb; + /* Need to work around a bug in two servers here */ + /* First, check if the part of bcc they sent was zero */ + if (tmp[sizeof(struct smb_hdr)] == 0) { + /* some servers return only half of bcc + * on simple responses (wct, bcc both zero) + * in particular have seen this on + * ulogoffX and FindClose. This leaves + * one byte of bcc potentially unitialized + */ + /* zero rest of bcc */ + tmp[sizeof(struct smb_hdr)+1] = 0; return 0; - } else { - cERROR(1, ("Length less than smb header size")); } + cERROR(1,("rcvd invalid byte count (bcc)")); + } else { + cERROR(1, ("Length less than smb header size")); } - if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) - cERROR(1, ("smb length greater than MaxBufSize, mid=%d", + return 1; + } + if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) { + cERROR(1, ("smb length greater than MaxBufSize, mid=%d", smb->Mid)); return 1; } @@ -446,7 +462,7 @@ checkSMB(struct smb_hdr *smb, __u16 mid, int length) return 1; clc_len = smbCalcSize_LE(smb); - if(4 + len != (unsigned int)length) { + if(4 + len != length) { cERROR(1, ("Length read does not match RFC1001 length %d",len)); return 1; } |