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 <sven.auhagen@voleatech.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 3f1ed467f951f6342d9ee8da6b576cf8c787af2d..2796153b03dad3213ad9c52d3c90c5846cfdb771 100644 (file)
--- 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,

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index a7f54eb68d9a003c6275b5936f893370c0bf93a1..be3b4c90d2eda11bc9218e38e5c97f5b2ecb4034 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3333,7 +3333,7 @@ err_expr_parse:
        return ERR_PTR(err);
 }
 
-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)
 {
        int err;
 
@@ -3341,7 +3341,7 @@ int nft_expr_clone(struct nft_expr *dst, struct nft_expr *src)
                return -EINVAL;
 
        dst->ops = src->ops;
-       err = src->ops->clone(dst, src);
+       err = src->ops->clone(dst, src, gfp);
        if (err < 0)
                return err;
 
@@ -6525,7 +6525,7 @@ int nft_set_elem_expr_clone(const struct nft_ctx *ctx, struct nft_set *set,
                if (!expr)
                        goto err_expr;
 
-               err = nft_expr_clone(expr, set->exprs[i]);
+               err = nft_expr_clone(expr, set->exprs[i], GFP_KERNEL_ACCOUNT);
                if (err < 0) {
                        kfree(expr);
                        goto err_expr;
@@ -6564,7 +6564,7 @@ static int nft_set_elem_expr_setup(struct nft_ctx *ctx,
 
        for (i = 0; i < num_exprs; i++) {
                expr = nft_setelem_expr_at(elem_expr, elem_expr->size);
-               err = nft_expr_clone(expr, expr_array[i]);
+               err = nft_expr_clone(expr, expr_array[i], GFP_KERNEL_ACCOUNT);
                if (err < 0)
                        goto err_elem_expr_setup;
 

diff --git a/net/netfilter/nft_connlimit.c b/net/netfilter/nft_connlimit.c
index de9d1980df6964b3b0da99560acce8ce9b5a2aa7..92b984fa8175c298f9829c34cf9f630d053a4e82 100644 (file)
--- a/net/netfilter/nft_connlimit.c
+++ b/net/netfilter/nft_connlimit.c
@@ -210,12 +210,12 @@ static void nft_connlimit_destroy(const struct nft_ctx *ctx,
        nft_connlimit_do_destroy(ctx, priv);
 }
 
-static int nft_connlimit_clone(struct nft_expr *dst, const struct nft_expr *src)
+static int nft_connlimit_clone(struct nft_expr *dst, const struct nft_expr *src, gfp_t gfp)
 {
        struct nft_connlimit *priv_dst = nft_expr_priv(dst);
        struct nft_connlimit *priv_src = nft_expr_priv(src);
 
-       priv_dst->list = kmalloc(sizeof(*priv_dst->list), GFP_ATOMIC);
+       priv_dst->list = kmalloc(sizeof(*priv_dst->list), gfp);
        if (!priv_dst->list)
                return -ENOMEM;
 

diff --git a/net/netfilter/nft_counter.c b/net/netfilter/nft_counter.c
index dccc68a5135add1433d48dc82b942420fd3ebd17..291ed2026367ec4a5b2b893caa3d5abfcf2c5959 100644 (file)
--- a/net/netfilter/nft_counter.c
+++ b/net/netfilter/nft_counter.c
@@ -226,7 +226,7 @@ static void nft_counter_destroy(const struct nft_ctx *ctx,
        nft_counter_do_destroy(priv);
 }
 
-static int nft_counter_clone(struct nft_expr *dst, const struct nft_expr *src)
+static int nft_counter_clone(struct nft_expr *dst, const struct nft_expr *src, gfp_t gfp)
 {
        struct nft_counter_percpu_priv *priv = nft_expr_priv(src);
        struct nft_counter_percpu_priv *priv_clone = nft_expr_priv(dst);
@@ -236,7 +236,7 @@ static int nft_counter_clone(struct nft_expr *dst, const struct nft_expr *src)
 
        nft_counter_fetch(priv, &total);
 
-       cpu_stats = alloc_percpu_gfp(struct nft_counter, GFP_ATOMIC);
+       cpu_stats = alloc_percpu_gfp(struct nft_counter, gfp);
        if (cpu_stats == NULL)
                return -ENOMEM;
 

diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c
index c09dba57354c17e0776e4d5c3b52486719d20163..b4ada3ab21679bc4e69f5810cd5590b7a2bbac96 100644 (file)
--- a/net/netfilter/nft_dynset.c
+++ b/net/netfilter/nft_dynset.c
@@ -35,7 +35,7 @@ static int nft_dynset_expr_setup(const struct nft_dynset *priv,
 
        for (i = 0; i < priv->num_exprs; i++) {
                expr = nft_setelem_expr_at(elem_expr, elem_expr->size);
-               if (nft_expr_clone(expr, priv->expr_array[i]) < 0)
+               if (nft_expr_clone(expr, priv->expr_array[i], GFP_ATOMIC) < 0)
                        return -1;
 
                elem_expr->size += priv->expr_array[i]->ops->size;

diff --git a/net/netfilter/nft_last.c b/net/netfilter/nft_last.c
index 8e6d7eaf9dc8b5c783b1a7591ff21608e41dcdaf..de1b6066bfa856d67bdc9342c2056f667f87cf91 100644 (file)
--- a/net/netfilter/nft_last.c
+++ b/net/netfilter/nft_last.c
@@ -102,12 +102,12 @@ static void nft_last_destroy(const struct nft_ctx *ctx,
        kfree(priv->last);
 }
 
-static int nft_last_clone(struct nft_expr *dst, const struct nft_expr *src)
+static int nft_last_clone(struct nft_expr *dst, const struct nft_expr *src, gfp_t gfp)
 {
        struct nft_last_priv *priv_dst = nft_expr_priv(dst);
        struct nft_last_priv *priv_src = nft_expr_priv(src);
 
-       priv_dst->last = kzalloc(sizeof(*priv_dst->last), GFP_ATOMIC);
+       priv_dst->last = kzalloc(sizeof(*priv_dst->last), gfp);
        if (!priv_dst->last)
                return -ENOMEM;
 

diff --git a/net/netfilter/nft_limit.c b/net/netfilter/nft_limit.c
index cefa25e0dbb0a2c87af43e8230cf7934ce8fa3d1..21d26b79b4607279e6fe61591fcaf98f42651aaa 100644 (file)
--- a/net/netfilter/nft_limit.c
+++ b/net/netfilter/nft_limit.c
@@ -150,7 +150,7 @@ static void nft_limit_destroy(const struct nft_ctx *ctx,
 }
 
 static int nft_limit_clone(struct nft_limit_priv *priv_dst,
-                          const struct nft_limit_priv *priv_src)
+                          const struct nft_limit_priv *priv_src, gfp_t gfp)
 {
        priv_dst->tokens_max = priv_src->tokens_max;
        priv_dst->rate = priv_src->rate;
@@ -158,7 +158,7 @@ static int nft_limit_clone(struct nft_limit_priv *priv_dst,
        priv_dst->burst = priv_src->burst;
        priv_dst->invert = priv_src->invert;
 
-       priv_dst->limit = kmalloc(sizeof(*priv_dst->limit), GFP_ATOMIC);
+       priv_dst->limit = kmalloc(sizeof(*priv_dst->limit), gfp);
        if (!priv_dst->limit)
                return -ENOMEM;
 
@@ -223,14 +223,15 @@ static void nft_limit_pkts_destroy(const struct nft_ctx *ctx,
        nft_limit_destroy(ctx, &priv->limit);
 }
 
-static int nft_limit_pkts_clone(struct nft_expr *dst, const struct nft_expr *src)
+static int nft_limit_pkts_clone(struct nft_expr *dst, const struct nft_expr *src,
+                               gfp_t gfp)
 {
        struct nft_limit_priv_pkts *priv_dst = nft_expr_priv(dst);
        struct nft_limit_priv_pkts *priv_src = nft_expr_priv(src);
 
        priv_dst->cost = priv_src->cost;
 
-       return nft_limit_clone(&priv_dst->limit, &priv_src->limit);
+       return nft_limit_clone(&priv_dst->limit, &priv_src->limit, gfp);
 }
 
 static struct nft_expr_type nft_limit_type;
@@ -281,12 +282,13 @@ static void nft_limit_bytes_destroy(const struct nft_ctx *ctx,
        nft_limit_destroy(ctx, priv);
 }
 
-static int nft_limit_bytes_clone(struct nft_expr *dst, const struct nft_expr *src)
+static int nft_limit_bytes_clone(struct nft_expr *dst, const struct nft_expr *src,
+                                gfp_t gfp)
 {
        struct nft_limit_priv *priv_dst = nft_expr_priv(dst);
        struct nft_limit_priv *priv_src = nft_expr_priv(src);
 
-       return nft_limit_clone(priv_dst, priv_src);
+       return nft_limit_clone(priv_dst, priv_src, gfp);
 }
 
 static const struct nft_expr_ops nft_limit_bytes_ops = {

diff --git a/net/netfilter/nft_quota.c b/net/netfilter/nft_quota.c
index 3ba12a7471b0f6210947cd09db9f582012f3d8c5..9b2d7463d3d32698069e93fdbc94f4910e1a3d55 100644 (file)
--- a/net/netfilter/nft_quota.c
+++ b/net/netfilter/nft_quota.c
@@ -233,7 +233,7 @@ static void nft_quota_destroy(const struct nft_ctx *ctx,
        return nft_quota_do_destroy(ctx, priv);
 }
 
-static int nft_quota_clone(struct nft_expr *dst, const struct nft_expr *src)
+static int nft_quota_clone(struct nft_expr *dst, const struct nft_expr *src, gfp_t gfp)
 {
        struct nft_quota *priv_dst = nft_expr_priv(dst);
        struct nft_quota *priv_src = nft_expr_priv(src);
@@ -241,7 +241,7 @@ static int nft_quota_clone(struct nft_expr *dst, const struct nft_expr *src)
        priv_dst->quota = priv_src->quota;
        priv_dst->flags = priv_src->flags;
 
-       priv_dst->consumed = kmalloc(sizeof(*priv_dst->consumed), GFP_ATOMIC);
+       priv_dst->consumed = kmalloc(sizeof(*priv_dst->consumed), gfp);
        if (!priv_dst->consumed)
                return -ENOMEM;