Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Pull CIFS fixes from Steve French:
 "A fix for the problem which Al spotted in cifs_writev and a followup
  (noticed when fixing CVE-2014-0069) patch to ensure that cifs never
  sends more than the smb frame length over the socket (as we saw with
  that cifs_iovec_write problem that Jeff fixed last month)"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: mask off top byte in get_rfc1002_length()
  cifs: sanity check length of data to send before sending
  CIFS: Fix wrong pos argument of cifs_find_lock_conflict
This commit is contained in:
Linus Torvalds 2014-03-11 11:53:42 -07:00
commit 33807f4f0d
3 changed files with 36 additions and 19 deletions

View File

@ -513,7 +513,7 @@ struct cifs_mnt_data {
static inline unsigned int
get_rfc1002_length(void *buf)
{
return be32_to_cpu(*((__be32 *)buf));
return be32_to_cpu(*((__be32 *)buf)) & 0xffffff;
}
static inline void

View File

@ -2579,31 +2579,19 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov,
struct cifsInodeInfo *cinode = CIFS_I(inode);
struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
ssize_t rc = -EACCES;
loff_t lock_pos = pos;
BUG_ON(iocb->ki_pos != pos);
if (file->f_flags & O_APPEND)
lock_pos = i_size_read(inode);
/*
* We need to hold the sem to be sure nobody modifies lock list
* with a brlock that prevents writing.
*/
down_read(&cinode->lock_sem);
if (!cifs_find_lock_conflict(cfile, pos, iov_length(iov, nr_segs),
if (!cifs_find_lock_conflict(cfile, lock_pos, iov_length(iov, nr_segs),
server->vals->exclusive_lock_type, NULL,
CIFS_WRITE_OP)) {
mutex_lock(&inode->i_mutex);
rc = __generic_file_aio_write(iocb, iov, nr_segs,
&iocb->ki_pos);
mutex_unlock(&inode->i_mutex);
}
if (rc > 0) {
ssize_t err;
err = generic_write_sync(file, iocb->ki_pos - rc, rc);
if (err < 0)
rc = err;
}
CIFS_WRITE_OP))
rc = generic_file_aio_write(iocb, iov, nr_segs, pos);
up_read(&cinode->lock_sem);
return rc;
}

View File

@ -270,6 +270,26 @@ cifs_rqst_page_to_kvec(struct smb_rqst *rqst, unsigned int idx,
iov->iov_len = rqst->rq_pagesz;
}
static unsigned long
rqst_len(struct smb_rqst *rqst)
{
unsigned int i;
struct kvec *iov = rqst->rq_iov;
unsigned long buflen = 0;
/* total up iov array first */
for (i = 0; i < rqst->rq_nvec; i++)
buflen += iov[i].iov_len;
/* add in the page array if there is one */
if (rqst->rq_npages) {
buflen += rqst->rq_pagesz * (rqst->rq_npages - 1);
buflen += rqst->rq_tailsz;
}
return buflen;
}
static int
smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
{
@ -277,6 +297,7 @@ smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
struct kvec *iov = rqst->rq_iov;
int n_vec = rqst->rq_nvec;
unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
unsigned long send_length;
unsigned int i;
size_t total_len = 0, sent;
struct socket *ssocket = server->ssocket;
@ -285,6 +306,14 @@ smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
if (ssocket == NULL)
return -ENOTSOCK;
/* sanity check send length */
send_length = rqst_len(rqst);
if (send_length != smb_buf_length + 4) {
WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n",
send_length, smb_buf_length);
return -EIO;
}
cifs_dbg(FYI, "Sending smb: smb_len=%u\n", smb_buf_length);
dump_smb(iov[0].iov_base, iov[0].iov_len);