2006-02-15 03:35:16

by Steve French

[permalink] [raw]
Subject: [PATCH] [CIFS] fix cifs_user_read oops when null SMB response on forcedirectio mount

This patch fixes an oops reported by Adrian Bunk in cifs_user_read when a null
read response is returned on a forcedirectio mount.

Signed-off-by: Dave Kleikamp <[email protected]>
Signed-off-by: Steve French <[email protected]>

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index d17c97d..675bd25 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1442,13 +1442,15 @@ ssize_t cifs_user_read(struct file *file
&bytes_read, &smb_read_data,
&buf_type);
pSMBr = (struct smb_com_read_rsp *)smb_read_data;
- if (copy_to_user(current_offset,
- smb_read_data + 4 /* RFC1001 hdr */
- + le16_to_cpu(pSMBr->DataOffset),
- bytes_read)) {
- rc = -EFAULT;
- }
if (smb_read_data) {
+ if (copy_to_user(current_offset,
+ smb_read_data +
+ 4 /* RFC1001 length field */ +
+ le16_to_cpu(pSMBr->DataOffset),
+ bytes_read)) {
+ rc = -EFAULT;
+ }
+
if(buf_type == CIFS_SMALL_BUFFER)
cifs_small_buf_release(smb_read_data);
else if(buf_type == CIFS_LARGE_BUFFER)



Attachments:
cifs-user-read-oops.patch (803.00 B)