From fa23e0d4b756d25829e124d6b670a4c6bbd4bf7e Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 8 May 2024 14:52:47 +0200 Subject: netfilter: nf_tables: allow clone callbacks to sleep Sven Auhagen reports transaction failures with following error: ./main.nft:13:1-26: Error: Could not process rule: Cannot allocate memory percpu: allocation failed, size=16 align=8 atomic=1, atomic alloc failed, no space left This points to failing pcpu allocation with GFP_ATOMIC flag. However, transactions happen from user context and are allowed to sleep. One case where we can call into percpu allocator with GFP_ATOMIC is nft_counter expression. Normally this happens from control plane, so this could use GFP_KERNEL instead. But one use case, element insertion from packet path, needs to use GFP_ATOMIC allocations (nft_dynset expression). At this time, .clone callbacks always use GFP_ATOMIC for this reason. Add gfp_t argument to the .clone function and pass GFP_KERNEL or GFP_ATOMIC flag depending on context, this allows all clone memory allocations to sleep for the normal (transaction) case. Cc: Sven Auhagen Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_tables.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/net') diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 3f1ed467f951..2796153b03da 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -416,7 +416,7 @@ struct nft_expr_info; int nft_expr_inner_parse(const struct nft_ctx *ctx, const struct nlattr *nla, struct nft_expr_info *info); -int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src); +int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src, gfp_t gfp); void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr); int nft_expr_dump(struct sk_buff *skb, unsigned int attr, const struct nft_expr *expr, bool reset); @@ -935,7 +935,7 @@ struct nft_expr_ops { struct nft_regs *regs, const struct nft_pktinfo *pkt); int (*clone)(struct nft_expr *dst, - const struct nft_expr *src); + const struct nft_expr *src, gfp_t gfp); unsigned int size; int (*init)(const struct nft_ctx *ctx, -- cgit v1.2.3