[PATCH RFC net-next 09/34] bpf, xdp: constify some bpf_prog * function arguments
From: Alexander Lobakin
Date: Fri Dec 22 2023 - 22:01:37 EST
In lots of places, bpf_prog pointer is used only for tracing or other
stuff that doesn't modify the structure itself. Same for net_device.
Address at least some of them and add `const` attributes there. The
object code didn't change, but that may prevent unwanted data
modifications and also allow more helpers to have const arguments.
Signed-off-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx>
---
include/linux/bpf.h | 12 ++++++------
include/linux/filter.h | 9 +++++----
include/linux/netdevice.h | 6 +++---
kernel/bpf/devmap.c | 8 ++++----
net/core/dev.c | 8 ++++----
net/core/filter.c | 25 ++++++++++++++-----------
6 files changed, 36 insertions(+), 32 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 7a8d4c81a39a..53ccac0f0d64 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2384,10 +2384,10 @@ int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_frame *xdpf,
int dev_map_enqueue_multi(struct xdp_frame *xdpf, struct net_device *dev_rx,
struct bpf_map *map, bool exclude_ingress);
int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
- struct bpf_prog *xdp_prog);
+ const struct bpf_prog *xdp_prog);
int dev_map_redirect_multi(struct net_device *dev, struct sk_buff *skb,
- struct bpf_prog *xdp_prog, struct bpf_map *map,
- bool exclude_ingress);
+ const struct bpf_prog *xdp_prog,
+ struct bpf_map *map, bool exclude_ingress);
void __cpu_map_flush(void);
int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_frame *xdpf,
@@ -2632,15 +2632,15 @@ struct sk_buff;
static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst,
struct sk_buff *skb,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
return 0;
}
static inline
int dev_map_redirect_multi(struct net_device *dev, struct sk_buff *skb,
- struct bpf_prog *xdp_prog, struct bpf_map *map,
- bool exclude_ingress)
+ const struct bpf_prog *xdp_prog,
+ struct bpf_map *map, bool exclude_ingress)
{
return 0;
}
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 68fb6c8142fe..34c9e2a4cc01 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1015,17 +1015,18 @@ static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
* This does not appear to be a real limitation for existing software.
*/
int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
- struct xdp_buff *xdp, struct bpf_prog *prog);
+ struct xdp_buff *xdp, const struct bpf_prog *prog);
int xdp_do_redirect(struct net_device *dev,
struct xdp_buff *xdp,
- struct bpf_prog *prog);
+ const struct bpf_prog *prog);
int xdp_do_redirect_frame(struct net_device *dev,
struct xdp_buff *xdp,
struct xdp_frame *xdpf,
- struct bpf_prog *prog);
+ const struct bpf_prog *prog);
void xdp_do_flush(void);
-void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act);
+void bpf_warn_invalid_xdp_action(const struct net_device *dev,
+ const struct bpf_prog *prog, u32 act);
#ifdef CONFIG_INET
struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 75c7725e5e4f..7bb8324a4ebe 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3956,9 +3956,9 @@ static inline void dev_consume_skb_any(struct sk_buff *skb)
}
u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog);
-void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog);
-int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb);
+ const struct bpf_prog *xdp_prog);
+void generic_xdp_tx(struct sk_buff *skb, const struct bpf_prog *xdp_prog);
+int do_xdp_generic(const struct bpf_prog *xdp_prog, struct sk_buff *skb);
int netif_rx(struct sk_buff *skb);
int __netif_rx(struct sk_buff *skb);
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index a936c704d4e7..5ad73ef21da2 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -673,7 +673,7 @@ int dev_map_enqueue_multi(struct xdp_frame *xdpf, struct net_device *dev_rx,
}
int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
int err;
@@ -696,7 +696,7 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
static int dev_map_redirect_clone(struct bpf_dtab_netdev *dst,
struct sk_buff *skb,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
struct sk_buff *nskb;
int err;
@@ -715,8 +715,8 @@ static int dev_map_redirect_clone(struct bpf_dtab_netdev *dst,
}
int dev_map_redirect_multi(struct net_device *dev, struct sk_buff *skb,
- struct bpf_prog *xdp_prog, struct bpf_map *map,
- bool exclude_ingress)
+ const struct bpf_prog *xdp_prog,
+ struct bpf_map *map, bool exclude_ingress)
{
struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
struct bpf_dtab_netdev *dst, *last_dst = NULL;
diff --git a/net/core/dev.c b/net/core/dev.c
index f9d4b550ef4b..b2a9839dd18e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4833,7 +4833,7 @@ static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
}
u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
void *orig_data, *orig_data_end, *hard_start;
struct netdev_rx_queue *rxqueue;
@@ -4922,7 +4922,7 @@ u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
static u32 netif_receive_generic_xdp(struct sk_buff *skb,
struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
u32 act = XDP_DROP;
@@ -4979,7 +4979,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
* and DDOS attacks will be more effective. In-driver-XDP use dedicated TX
* queues, so they do not have this starvation issue.
*/
-void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
+void generic_xdp_tx(struct sk_buff *skb, const struct bpf_prog *xdp_prog)
{
struct net_device *dev = skb->dev;
struct netdev_queue *txq;
@@ -5004,7 +5004,7 @@ void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key);
-int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
+int do_xdp_generic(const struct bpf_prog *xdp_prog, struct sk_buff *skb)
{
if (xdp_prog) {
struct xdp_buff xdp;
diff --git a/net/core/filter.c b/net/core/filter.c
index 24061f29c9dd..4ace1edc4de1 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4297,9 +4297,9 @@ u32 xdp_master_redirect(struct xdp_buff *xdp)
EXPORT_SYMBOL_GPL(xdp_master_redirect);
static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
- struct net_device *dev,
+ const struct net_device *dev,
struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
enum bpf_map_type map_type = ri->map_type;
void *fwd = ri->tgt_value;
@@ -4320,10 +4320,10 @@ static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
return err;
}
-static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
- struct net_device *dev,
- struct xdp_frame *xdpf,
- struct bpf_prog *xdp_prog)
+static __always_inline int
+__xdp_do_redirect_frame(struct bpf_redirect_info *ri, struct net_device *dev,
+ struct xdp_frame *xdpf,
+ const struct bpf_prog *xdp_prog)
{
enum bpf_map_type map_type = ri->map_type;
void *fwd = ri->tgt_value;
@@ -4381,7 +4381,7 @@ static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
}
int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog)
+ const struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
enum bpf_map_type map_type = ri->map_type;
@@ -4395,7 +4395,8 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
EXPORT_SYMBOL_GPL(xdp_do_redirect);
int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp,
- struct xdp_frame *xdpf, struct bpf_prog *xdp_prog)
+ struct xdp_frame *xdpf,
+ const struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
enum bpf_map_type map_type = ri->map_type;
@@ -4410,7 +4411,7 @@ EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);
static int xdp_do_generic_redirect_map(struct net_device *dev,
struct sk_buff *skb,
struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog,
+ const struct bpf_prog *xdp_prog,
void *fwd,
enum bpf_map_type map_type, u32 map_id)
{
@@ -4457,7 +4458,8 @@ static int xdp_do_generic_redirect_map(struct net_device *dev,
}
int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
- struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
+ struct xdp_buff *xdp,
+ const struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
enum bpf_map_type map_type = ri->map_type;
@@ -8961,7 +8963,8 @@ static bool xdp_is_valid_access(int off, int size,
return __is_valid_xdp_access(off, size);
}
-void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
+void bpf_warn_invalid_xdp_action(const struct net_device *dev,
+ const struct bpf_prog *prog, u32 act)
{
const u32 act_max = XDP_REDIRECT;
--
2.43.0