RDMA/rxe: bound the WQE opcode before indexing rxe_wr_opcode_info[]

wr_opcode_mask() indexes the global rxe_wr_opcode_info[] array with
a caller-supplied opcode and no bounds check. For a user QP the WQE
comes from an mmap'd SQ ring, so wqe->wr.opcode is an
attacker-controlled __u32 read back by the requester
(req_next_wqe() -> rxe_requester()); rxe_post_send() takes the
qp->is_user branch and never runs validate_send_wr(), whose only
opcode check is itself !wr_opcode_mask() (it indexes before it
checks). rxe_wr_opcode_info[] has entries only up to IB_WR_REG_MR,
so an out-of-range opcode reads out of bounds and the result is used
as a mask and dereferenced; observed as a KASAN global-out-of-bounds
"Read of size 4" and a wild-pointer oops.

Return a zero mask for an out-of-range opcode, matching how
validate_send_wr() already treats a zero mask (an invalid WR), so no
path indexes the array out of bounds.

Fixes: 8700e3e7c485 ("Soft RoCE driver")
Signed-off-by: Youngsung Ahn <ays511.kr@gmail.com>
Link: https://patch.msgid.link/20261002164552.294749-1-ays511.kr@gmail.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

0 files changed, 0 insertions, 0 deletions