cifs: fix unaligned access in check2ndT2 and coalesce_t2

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index ca20e81..18d3c77 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -232,9 +232,8 @@ cifs_reconnect(struct TCP_Server_Info *server)
 static int check2ndT2(struct smb_hdr *pSMB, unsigned int maxBufSize)
 {
        struct smb_t2_rsp *pSMBt;
-       int total_data_size;
-       int data_in_this_rsp;
        int remaining;
+       __u16 total_data_size, data_in_this_rsp;
 
        if (pSMB->Command != SMB_COM_TRANSACTION2)
                return 0;
@@ -248,8 +247,8 @@ static int check2ndT2(struct smb_hdr *pSMB, unsigned int maxBufSize)
 
        pSMBt = (struct smb_t2_rsp *)pSMB;
 
-       total_data_size = le16_to_cpu(pSMBt->t2_rsp.TotalDataCount);
-       data_in_this_rsp = le16_to_cpu(pSMBt->t2_rsp.DataCount);
+       total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
+       data_in_this_rsp = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
 
        remaining = total_data_size - data_in_this_rsp;
 
@@ -275,21 +274,18 @@ static int coalesce_t2(struct smb_hdr *psecond, struct smb_hdr *pTargetSMB)
 {
        struct smb_t2_rsp *pSMB2 = (struct smb_t2_rsp *)psecond;
        struct smb_t2_rsp *pSMBt  = (struct smb_t2_rsp *)pTargetSMB;
-       int total_data_size;
-       int total_in_buf;
-       int remaining;
-       int total_in_buf2;
        char *data_area_of_target;
        char *data_area_of_buf2;
-       __u16 byte_count;
+       int remaining;
+       __u16 byte_count, total_data_size, total_in_buf, total_in_buf2;
 
-       total_data_size = le16_to_cpu(pSMBt->t2_rsp.TotalDataCount);
+       total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
 
-       if (total_data_size != le16_to_cpu(pSMB2->t2_rsp.TotalDataCount)) {
+       if (total_data_size !=
+           get_unaligned_le16(&pSMB2->t2_rsp.TotalDataCount))
                cFYI(1, "total data size of primary and secondary t2 differ");
-       }
 
-       total_in_buf = le16_to_cpu(pSMBt->t2_rsp.DataCount);
+       total_in_buf = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
 
        remaining = total_data_size - total_in_buf;
 
@@ -299,25 +295,25 @@ static int coalesce_t2(struct smb_hdr *psecond, struct smb_hdr *pTargetSMB)
        if (remaining == 0) /* nothing to do, ignore */
                return 0;
 
-       total_in_buf2 = le16_to_cpu(pSMB2->t2_rsp.DataCount);
+       total_in_buf2 = get_unaligned_le16(&pSMB2->t2_rsp.DataCount);
        if (remaining < total_in_buf2) {
                cFYI(1, "transact2 2nd response contains too much data");
        }
 
        /* find end of first SMB data area */
        data_area_of_target = (char *)&pSMBt->hdr.Protocol +
-                               le16_to_cpu(pSMBt->t2_rsp.DataOffset);
+                               get_unaligned_le16(&pSMBt->t2_rsp.DataOffset);
        /* validate target area */
 
-       data_area_of_buf2 = (char *) &pSMB2->hdr.Protocol +
-                                       le16_to_cpu(pSMB2->t2_rsp.DataOffset);
+       data_area_of_buf2 = (char *)&pSMB2->hdr.Protocol +
+                               get_unaligned_le16(&pSMB2->t2_rsp.DataOffset);
 
        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;
-       pSMBt->t2_rsp.DataCount = cpu_to_le16(total_in_buf);
+       put_unaligned_le16(total_in_buf, &pSMBt->t2_rsp.DataCount);
        byte_count = get_bcc_le(pTargetSMB);
        byte_count += total_in_buf2;
        put_bcc_le(byte_count, pTargetSMB);
@@ -334,7 +330,6 @@ static int coalesce_t2(struct smb_hdr *psecond, struct smb_hdr *pTargetSMB)
                return 0; /* we are done */
        } else /* more responses to go */
                return 1;
-
 }
 
 static void