4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> commit 99975cd4fda52974a767aa44fe0b1a8f74950d9d upstream. ib_map_mr_sg() can pass an SG-list to .map_mr_sg() that is larger than what fits into a single MR. .map_mr_sg() must not attempt to map more SG-list elements than what fits into a single MR. Hence make sure that mlx5_ib_sg_to_klms() does not write outside the MR klms[] array. Fixes: b005d3164713 ("mlx5: Add arbitrary sg list support") Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> Reviewed-by: Max Gurtovoy <maxg@xxxxxxxxxxxx> Cc: Sagi Grimberg <sagi@xxxxxxxxxxx> Cc: Leon Romanovsky <leonro@xxxxxxxxxxxx> Cc: Israel Rukshin <israelr@xxxxxxxxxxxx> Acked-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx> Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/mr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -1779,7 +1779,7 @@ mlx5_ib_sg_to_klms(struct mlx5_ib_mr *mr mr->ndescs = sg_nents; for_each_sg(sgl, sg, sg_nents, i) { - if (unlikely(i > mr->max_descs)) + if (unlikely(i >= mr->max_descs)) break; klms[i].va = cpu_to_be64(sg_dma_address(sg) + sg_offset); klms[i].bcount = cpu_to_be32(sg_dma_len(sg) - sg_offset);