diff options
author | Elena Reshetova <elena.reshetova@intel.com> | 2017-10-20 10:23:41 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-10-22 02:22:39 +0100 |
commit | dd8e19456d60a519de1852ae4b1be7d62690d2e0 (patch) | |
tree | 9651255b61c077d53fad6a628b7527169eb78239 /drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | |
parent | a4b51a9f83c6d359ff8fc0c66009283b6fdeeaf8 (diff) |
drivers, net, mlx5: convert fs_node.refcount from atomic_t to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable fs_node.refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx5/core/fs_core.h')
-rw-r--r-- | drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h index 80f6f3c714c8..397d24a621a4 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h @@ -33,6 +33,7 @@ #ifndef _MLX5_FS_CORE_ #define _MLX5_FS_CORE_ +#include <linux/refcount.h> #include <linux/mlx5/fs.h> #include <linux/rhashtable.h> @@ -84,7 +85,7 @@ struct fs_node { struct fs_node *root; /* lock the node for writing and traversing */ struct rw_semaphore lock; - atomic_t refcount; + refcount_t refcount; bool active; void (*del_hw_func)(struct fs_node *); void (*del_sw_func)(struct fs_node *); |