diff options
| author | Stanislav Fomichev <sdf@fomichev.me> | 2025-08-18 08:40:32 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-08-19 17:54:44 -0700 |
| commit | a890348adcc993f48d1ae38f1174dc8de4c3c5ac (patch) | |
| tree | e59b1568849dd3915b097159462998e8f3110e2c /include/linux | |
| parent | 3e31075a119409613627517f205edd86a7f89d7b (diff) | |
net: Add skb_dst_check_unset
To prevent dst_entry leaks, add warning when the non-NULL dst_entry
is rewritten.
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250818154032.3173645-8-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/skbuff.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 7538ca507ee9..ca8be45dd8be 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1159,6 +1159,12 @@ static inline struct dst_entry *skb_dst(const struct sk_buff *skb) return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK); } +static inline void skb_dst_check_unset(struct sk_buff *skb) +{ + DEBUG_NET_WARN_ON_ONCE((skb->_skb_refdst & SKB_DST_PTRMASK) && + !(skb->_skb_refdst & SKB_DST_NOREF)); +} + /** * skb_dstref_steal() - return current dst_entry value and clear it * @skb: buffer @@ -1188,6 +1194,7 @@ static inline unsigned long skb_dstref_steal(struct sk_buff *skb) */ static inline void skb_dstref_restore(struct sk_buff *skb, unsigned long refdst) { + skb_dst_check_unset(skb); skb->_skb_refdst = refdst; } @@ -1201,6 +1208,7 @@ static inline void skb_dstref_restore(struct sk_buff *skb, unsigned long refdst) */ static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) { + skb_dst_check_unset(skb); skb->slow_gro |= !!dst; skb->_skb_refdst = (unsigned long)dst; } @@ -1217,6 +1225,7 @@ static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) */ static inline void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst) { + skb_dst_check_unset(skb); WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); skb->slow_gro |= !!dst; skb->_skb_refdst = (unsigned long)dst | SKB_DST_NOREF; |