[CIFS] Fix large (ie over 64K for MaxCIFSBufSize) buffer case for wrapping
bcc on read response and for wrapping sessionsetup maxbufsize field
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 0f3ebad..988b8ce 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -421,9 +421,7 @@
{
__u32 len = smb->smb_buf_length;
__u32 clc_len; /* calculated length */
- cFYI(0,
- ("Entering checkSMB with Length: %x, smb_buf_length: %x",
- length, len));
+ 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)) {
@@ -435,22 +433,29 @@
} else {
cERROR(1, ("Length less than smb header size"));
}
-
}
if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)
- cERROR(1,
- ("smb_buf_length greater than MaxBufSize"));
- cERROR(1,
- ("bad smb detected. Illegal length. mid=%d",
- smb->Mid));
+ cERROR(1, ("smb length greater than MaxBufSize, mid=%d",
+ smb->Mid));
return 1;
}
if (checkSMBhdr(smb, mid))
return 1;
clc_len = smbCalcSize_LE(smb);
- if ((4 + len != clc_len)
- || (4 + len != (unsigned int)length)) {
+
+ if(4 + len != (unsigned int)length) {
+ cERROR(1, ("Length read does not match RFC1001 length %d",len));
+ return 1;
+ }
+
+ if (4 + len != clc_len) {
+ /* check if bcc wrapped around for large read responses */
+ if((len > 64 * 1024) && (len > clc_len)) {
+ /* check if lengths match mod 64K */
+ if(((4 + len) & 0xFFFF) == (clc_len & 0xFFFF))
+ return 0; /* bcc wrapped */
+ }
cERROR(1, ("Calculated size 0x%x vs actual length 0x%x",
clc_len, 4 + len));
cERROR(1, ("bad smb size detected for Mid=%d", smb->Mid));