cifs: ensure that uncached writes handle unmapped areas correctly
It's possible for userland to pass down an iovec via writev() that has a
bogus user pointer in it. If that happens and we're doing an uncached
write, then we can end up getting less bytes than we expect from the
call to iov_iter_copy_from_user. This is CVE-2014-0069
cifs_iovec_write isn't set up to handle that situation however. It'll
blindly keep chugging through the page array and not filling those pages
with anything useful. Worse yet, we'll later end up with a negative
number in wdata->tailsz, which will confuse the sending routines and
cause an oops at the very least.
Fix this by having the copy phase of cifs_iovec_write stop copying data
in this situation and send the last write as a short one. At the same
time, we want to avoid sending a zero-length write to the server, so
break out of the loop and set rc to -EFAULT if that happens. This also
allows us to handle the case where no address in the iovec is valid.
[Note: Marking this for stable on v3.4+ kernels, but kernels as old as
v2.6.38 may have a similar problem and may need similar fix]
Cc: <email address hidden> # v3.4+
Reviewed-by: Pavel Shilovsky <email address hidden>
Reported-by: Al Viro <email address hidden>
Signed-off-by: Jeff Layton <email address hidden>
Signed-off-by: Steve French <email address hidden>
(cherry picked from commit 5d81de8e8667da7135d3a32a964087c0faf5483f)
Signed-off-by: Andy Whitcroft <email address hidden>
UBUNTU: [Config] armhf: TI_CPSW, TI_CPTS and TI_DAVINCI_[CPDMA|MDIO] = y
Build in support for TI's three port switch gigabit ethernet subsystem (CPSW)
and while here turn on Common Platform Time Sync (CPTS) support that offers
hw time stamping and a PTP hardware clock.
TI_DAVINCI_[CPDMA|MDIO] are helpers to access SOC's nic.
Signed-off-by: Paolo Pisati <email address hidden>
Signed-off-by: Andy Whitcroft <email address hidden>
