Does this "err = -EFAULT;" make any sense in your commit? Zhu Yanjun -----Original Message----- From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Sent: Tuesday, May 12, 2020 2:38 AM To: Yanjun Zhu <yanjunz@xxxxxxxxxxxx>; Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx> Cc: Doug Ledford <dledford@xxxxxxxxxx>; Jason Gunthorpe <jgg@xxxxxxxx>; linux-rdma@xxxxxxxxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx Subject: [PATCH] RDMA/rxe: Return -EFAULT if copy_from_user() fails This function used to always return -EINVAL but we updated it to try preserve the error codes. Unfortunately the copy_to_user() is returning the number of bytes remaining to be copied instead of a negative error code. Fixes: a3a974b4654d ("RDMA/rxe: Always return ERR_PTR from rxe_create_mmap_info()") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- drivers/infiniband/sw/rxe/rxe_queue.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/sw/rxe/rxe_queue.c b/drivers/infiniband/sw/rxe/rxe_queue.c index fef2ab5112de5..245040c3a35d0 100644 --- a/drivers/infiniband/sw/rxe/rxe_queue.c +++ b/drivers/infiniband/sw/rxe/rxe_queue.c @@ -50,9 +50,10 @@ int do_mmap_info(struct rxe_dev *rxe, struct mminfo __user *outbuf, goto err1; } - err = copy_to_user(outbuf, &ip->info, sizeof(ip->info)); - if (err) + if (copy_to_user(outbuf, &ip->info, sizeof(ip->info))) { + err = -EFAULT; goto err2; + } spin_lock_bh(&rxe->pending_lock); list_add(&ip->pending_mmaps, &rxe->pending_mmaps); -- 2.26.2