RDMA/mlx5: Fix integer overflow of user QP buffer size

Browse source

set_user_buf_size() computes the QP buffer size by left-shifting the
user-supplied rq.wqe_cnt and rq.wqe_shift values as signed integers.
A sufficiently large rq.wqe_cnt causes signed integer overflow, which
is undefined behavior, and yields a small or negative buf_size, causing
ib_umem_get() to map a buffer smaller than the hardware will actually
write into.

Replace the shifts and addition with check_shl_overflow() and
check_add_overflow(), rejecting invalid user inputs.

Moreover, guard the identical shift computing qp->sq.offset in
_create_user_qp() before set_user_buf_size() is reached.

Fixes: e126ba97db ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Signed-off-by: Edward Srouji <edwards@nvidia.com>
Link: https://patch.msgid.link/20260723-fix-qp-buf-size-overflow-v1-1-ccb05ee43a7b@nvidia.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

...

This commit is contained in:

Maher Sanalla 2026-07-23 18:23:49 +03:00 • committed by Leon Romanovsky

parent 0087470661

commit dec47e4b0f

1 changed files with 20 additions and 5 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

25

drivers/infiniband/hw/mlx5/qp.c

View file