diff options
| author | Jason Gunthorpe <jgg@mellanox.com> | 2018-03-20 14:19:47 -0600 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@mellanox.com> | 2018-03-27 14:25:08 -0600 |
| commit | 611cb92b082ad16b2fe1258e51d5aca7de540dfb (patch) | |
| tree | 641fe2e35df9c9441bcf8b324bc179f1b219e86c | |
| parent | 38b48808b9af55f02cb226a1f09b7a5e67104569 (diff) | |
RDMA/ucma: Fix uABI structure layouts for 32/64 compat
The rdma_ucm_event_resp is a different length on 32 and 64 bit compiles.
The kernel requires it to be the expected length or longer so 32 bit
builds running on a 64 bit kernel will not work.
Retain full compat by having all kernels accept a struct with or without
the trailing reserved field.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
| -rw-r--r-- | drivers/infiniband/core/ucma.c | 9 | ||||
| -rw-r--r-- | include/uapi/rdma/rdma_user_cm.h | 5 |
2 files changed, 12 insertions, 2 deletions
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index 4bb5bed596c9..db4190b2ed27 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -382,7 +382,11 @@ static ssize_t ucma_get_event(struct ucma_file *file, const char __user *inbuf, struct ucma_event *uevent; int ret = 0; - if (out_len < sizeof uevent->resp) + /* + * Old 32 bit user space does not send the 4 byte padding in the + * reserved field. We don't care, allow it to keep working. + */ + if (out_len < sizeof(uevent->resp) - sizeof(uevent->resp.reserved)) return -ENOSPC; if (copy_from_user(&cmd, inbuf, sizeof(cmd))) @@ -417,7 +421,8 @@ static ssize_t ucma_get_event(struct ucma_file *file, const char __user *inbuf, } if (copy_to_user((void __user *)(unsigned long)cmd.response, - &uevent->resp, sizeof uevent->resp)) { + &uevent->resp, + min_t(size_t, out_len, sizeof(uevent->resp)))) { ret = -EFAULT; goto done; } diff --git a/include/uapi/rdma/rdma_user_cm.h b/include/uapi/rdma/rdma_user_cm.h index c83ef0026079..65399c837762 100644 --- a/include/uapi/rdma/rdma_user_cm.h +++ b/include/uapi/rdma/rdma_user_cm.h @@ -270,10 +270,15 @@ struct rdma_ucm_event_resp { __u32 id; __u32 event; __u32 status; + /* + * NOTE: This union is not aligned to 8 bytes so none of the union + * members may contain a u64 or anything with higher alignment than 4. + */ union { struct rdma_ucm_conn_param conn; struct rdma_ucm_ud_param ud; } param; + __u32 reserved; }; /* Option levels */ |