Replace the manual udata input copy and validation during
QP creation with the robust helper.
The irdma driver is backwards compatible with the legacy
i40iw userspace provider. The current create_qp ABI contains
two 8 byte fields. The legacy i40iw ABI was the same but
also contained two additional fields which were never actually
used. Furthermore, the i40iw userspace provider never explicitly
zero-initialized those extra fields, so there is a chance that
existing binaries are passing non-zero garbage values down
to the kernel.
Previously, the irdma driver only copied out the first 16
bytes and did not have any check for the rest of the buffer
being zero, so that additional garbage didn't matter.
By switching to ib_copy_validate_udata_in(), we will now be
checking to ensure that data beyond the kernel's definition
of the request is all zero.
In order to avoid breaking legacy binaries, we therefore need
to increase the request structure size to cover those garbage
fields.
- Legacy binaries will continue to pass down a 32 byte request,
with the driver copying the entire 32 bytes out but ignoring
the second 16 bytes, just as before.
- Newer binaries will pass down the normal 16 byte request. The
ib_copy_validate_udata_in() call will allow this to succeed
because we use user_compl_ctx as our minimum length (16 bytes).
- If the request is ever extended, the new fields would be
added after the "don't use" fields and would work as per
the normal uAPI mechanism.
Signed-off-by: Jacob Moroni <jmoroni@google.com>
Link: https://patch.msgid.link/20260713171257.3131493-5-jmoroni@google.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
173fc2b8dc