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173fc2b8dc
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>