From: Bart Van Assche bvanassche@acm.org
[ Upstream commit fb3063d31995cc4cf1d47a406bb61d6fb1b1d58d ]
From the comment above the definition of the roundup_pow_of_two() macro:
The result is undefined when n == 0.
Hence only pass positive values to roundup_pow_of_two(). This patch fixes the following UBSAN complaint:
UBSAN: Undefined behaviour in ./include/linux/log2.h:57:13 shift exponent 64 is too large for 64-bit type 'long unsigned int' Call Trace: dump_stack+0xa5/0xe6 ubsan_epilogue+0x9/0x26 __ubsan_handle_shift_out_of_bounds.cold+0x4c/0xf9 rxe_qp_from_attr.cold+0x37/0x5d [rdma_rxe] rxe_modify_qp+0x59/0x70 [rdma_rxe] _ib_modify_qp+0x5aa/0x7c0 [ib_core] ib_modify_qp+0x3b/0x50 [ib_core] cma_modify_qp_rtr+0x234/0x260 [rdma_cm] __rdma_accept+0x1a7/0x650 [rdma_cm] nvmet_rdma_cm_handler+0x1286/0x14cd [nvmet_rdma] cma_cm_event_handler+0x6b/0x330 [rdma_cm] cma_ib_req_handler+0xe60/0x22d0 [rdma_cm] cm_process_work+0x30/0x140 [ib_cm] cm_req_handler+0x11f4/0x1cd0 [ib_cm] cm_work_handler+0xb8/0x344e [ib_cm] process_one_work+0x569/0xb60 worker_thread+0x7a/0x5d0 kthread+0x1e6/0x210 ret_from_fork+0x24/0x30
Link: https://lore.kernel.org/r/20200217205714.26937-1-bvanassche@acm.org Fixes: 8700e3e7c485 ("Soft RoCE driver") Signed-off-by: Bart Van Assche bvanassche@acm.org Reviewed-by: Leon Romanovsky leonro@mellanox.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/sw/rxe/rxe_qp.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_qp.c b/drivers/infiniband/sw/rxe/rxe_qp.c index 230697fa31fe3..8a22ab8b29e9b 100644 --- a/drivers/infiniband/sw/rxe/rxe_qp.c +++ b/drivers/infiniband/sw/rxe/rxe_qp.c @@ -583,15 +583,16 @@ int rxe_qp_from_attr(struct rxe_qp *qp, struct ib_qp_attr *attr, int mask, int err;
if (mask & IB_QP_MAX_QP_RD_ATOMIC) { - int max_rd_atomic = __roundup_pow_of_two(attr->max_rd_atomic); + int max_rd_atomic = attr->max_rd_atomic ? + roundup_pow_of_two(attr->max_rd_atomic) : 0;
qp->attr.max_rd_atomic = max_rd_atomic; atomic_set(&qp->req.rd_atomic, max_rd_atomic); }
if (mask & IB_QP_MAX_DEST_RD_ATOMIC) { - int max_dest_rd_atomic = - __roundup_pow_of_two(attr->max_dest_rd_atomic); + int max_dest_rd_atomic = attr->max_dest_rd_atomic ? + roundup_pow_of_two(attr->max_dest_rd_atomic) : 0;
qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;