From: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
The intent of this VMA was to be read-only from user space, but the
VM_MAYWRITE masking was missed, so mprotect could make it writable.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 5c99eaecb1fc ("IB/mlx5: Mmap the HCA's clock info to user-space")
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Reviewed-by: Haggai Eran <haggaie@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/main.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 15676a149680..73b7f9636f82 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -2072,6 +2072,7 @@ static int mlx5_ib_mmap_clock_info_page(struct mlx5_ib_dev *dev,
if (vma->vm_flags & VM_WRITE)
return -EPERM;
+ vma->vm_flags &= ~VM_MAYWRITE;
if (!dev->mdev->clock_info_page)
return -EOPNOTSUPP;
@@ -2237,6 +2238,7 @@ static int mlx5_ib_mmap(struct ib_ucontext *ibcontext, struct vm_area_struct *vm
if (vma->vm_flags & VM_WRITE)
return -EPERM;
+ vma->vm_flags &= ~VM_MAYWRITE;
/* Don't expose to user-space information it shouldn't have */
if (PAGE_SIZE > 4096)
--
2.20.1
