Since ib_copy_from_udata() doesn't check yet the available input data
length before accessing userspace memory, an explicit check of this
length is required to prevent:
- reading past the user provided buffer,
- underflow when subtracting the expected command size from the input
length.
This will ensure the newly added flow steering uverbs don't try to
process truncated commands.
Link: http://marc.info/?i=cover.1386798254.git.ydroneaud@opteya.com>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
6bcca3d4a3