From: Majd Dibbiny <majd@xxxxxxxxxxxx>
User-space applications can do mmap and munmap directly.
Since the VMA list is not protected with a mutex, concurrent
accesses to the VMA list from the mmap and munmap can cause
data corruption.
Cc: <stable@xxxxxxxxxxxxxxx> # v4.7
Fixes: 7c2344c3bbf9 ("IB/mlx5: Implements disassociate_ucontext API")
Reviewed-by: Yishai Hadas <yishaih@xxxxxxxxxxxx>
Signed-off-by: Majd Dibbiny <majd@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/main.c | 8 ++++++++
drivers/infiniband/hw/mlx5/mlx5_ib.h | 6 ++++++
2 files changed, 14 insertions(+)
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index b4ef4d9b6ce5..8ac50de2b242 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -1463,6 +1463,7 @@ static struct ib_ucontext *mlx5_ib_alloc_ucontext(struct ib_device *ibdev,
}
INIT_LIST_HEAD(&context->vma_private_list);
+ mutex_init(&context->vma_private_list_mutex);
INIT_LIST_HEAD(&context->db_page_list);
mutex_init(&context->db_page_mutex);
@@ -1624,7 +1625,9 @@ static void mlx5_ib_vma_close(struct vm_area_struct *area)
* mlx5_ib_disassociate_ucontext().
*/
mlx5_ib_vma_priv_data->vma = NULL;
+ mutex_lock(mlx5_ib_vma_priv_data->vma_private_list_mutex);
list_del(&mlx5_ib_vma_priv_data->list);
+ mutex_unlock(mlx5_ib_vma_priv_data->vma_private_list_mutex);
kfree(mlx5_ib_vma_priv_data);
}
@@ -1644,10 +1647,13 @@ static int mlx5_ib_set_vma_data(struct vm_area_struct *vma,
return -ENOMEM;
vma_prv->vma = vma;
+ vma_prv->vma_private_list_mutex = &ctx->vma_private_list_mutex;
vma->vm_private_data = vma_prv;
vma->vm_ops = &mlx5_ib_vm_ops;
+ mutex_lock(&ctx->vma_private_list_mutex);
list_add(&vma_prv->list, vma_head);
+ mutex_unlock(&ctx->vma_private_list_mutex);
return 0;
}
@@ -1690,6 +1696,7 @@ static void mlx5_ib_disassociate_ucontext(struct ib_ucontext *ibcontext)
* mlx5_ib_vma_close.
*/
down_write(&owning_mm->mmap_sem);
+ mutex_lock(&context->vma_private_list_mutex);
list_for_each_entry_safe(vma_private, n, &context->vma_private_list,
list) {
vma = vma_private->vma;
@@ -1704,6 +1711,7 @@ static void mlx5_ib_disassociate_ucontext(struct ib_ucontext *ibcontext)
list_del(&vma_private->list);
kfree(vma_private);
}
+ mutex_unlock(&context->vma_private_list_mutex);
up_write(&owning_mm->mmap_sem);
mmput(owning_mm);
put_task_struct(owning_process);
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 6dd8cac78de2..dcf30e18409e 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -115,6 +115,9 @@ enum {
struct mlx5_ib_vma_private_data {
struct list_head list;
struct vm_area_struct *vma;
+ /* protect vma_private_list add/del
+ */
+ struct mutex *vma_private_list_mutex;
};
struct mlx5_ib_ucontext {
@@ -129,6 +132,9 @@ struct mlx5_ib_ucontext {
/* Transport Domain number */
u32 tdn;
struct list_head vma_private_list;
+ /* protect vma_private_list add/del
+ */
+ struct mutex vma_private_list_mutex;
unsigned long upd_xlt_page;
/* protect ODP/KSM */
--
2.15.1
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