This is a note to let you know that I've just added the patch titled IB/mlx5: Serialize access to the VMA list to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ib-mlx5-serialize-access-to-the-vma-list.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ad9a3668a434faca1339789ed2f043d679199309 Mon Sep 17 00:00:00 2001 From: Majd Dibbiny <majd@xxxxxxxxxxxx> Date: Sun, 24 Dec 2017 13:54:56 +0200 Subject: IB/mlx5: Serialize access to the VMA list From: Majd Dibbiny <majd@xxxxxxxxxxxx> commit ad9a3668a434faca1339789ed2f043d679199309 upstream. User-space applications can do mmap and munmap directly at any time. 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. Add a mutex around the list. 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> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/main.c | 8 ++++++++ drivers/infiniband/hw/mlx5/mlx5_ib.h | 4 ++++ 2 files changed, 12 insertions(+) --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -1415,6 +1415,7 @@ static struct ib_ucontext *mlx5_ib_alloc } 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); @@ -1576,7 +1577,9 @@ static void mlx5_ib_vma_close(struct vm * 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); } @@ -1596,10 +1599,13 @@ static int mlx5_ib_set_vma_data(struct v 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; } @@ -1642,6 +1648,7 @@ static void mlx5_ib_disassociate_ucontex * 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; @@ -1656,6 +1663,7 @@ static void mlx5_ib_disassociate_ucontex 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); --- a/drivers/infiniband/hw/mlx5/mlx5_ib.h +++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h @@ -115,6 +115,8 @@ 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 +131,8 @@ 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 */ Patches currently in stable-queue which might be from majd@xxxxxxxxxxxx are queue-4.14/ib-mlx5-serialize-access-to-the-vma-list.patch