From 3e67f106f619dcfaf6f4e2039599bdb69848c714 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 31 Mar 2018 12:58:53 -0700 Subject: [PATCH] inet: frags: break the 2GB limit for frags storage Some users are willing to provision huge amounts of memory to be able to perform reassembly reasonnably well under pressure. Current memory tracking is using one atomic_t and integers. Switch to atomic_long_t so that 64bit arches can use more than 2GB, without any cost for 32bit arches. Note that this patch avoids an overflow error, if high_thresh was set to ~2GB, since this test in inet_frag_alloc() was never true : if (... || frag_mem_limit(nf) > nf->high_thresh) Tested: $ echo 16000000000 >/proc/sys/net/ipv4/ipfrag_high_thresh $ grep FRAG /proc/net/sockstat FRAG: inuse 14705885 memory 16000002880 $ nstat -n ; sleep 1 ; nstat | grep Reas IpReasmReqds 3317150 0.0 IpReasmFails 3317112 0.0 Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 4 ++-- include/net/inet_frag.h | 20 ++++++++++---------- net/ieee802154/6lowpan/reassembly.c | 10 +++++----- net/ipv4/ip_fragment.c | 10 +++++----- net/ipv4/proc.c | 2 +- net/ipv6/netfilter/nf_conntrack_reasm.c | 10 +++++----- net/ipv6/proc.c | 2 +- net/ipv6/reassembly.c | 6 +++--- 8 files changed, 32 insertions(+), 32 deletions(-) diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 6f2a3670e44b..5dc1a040a2f1 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -133,10 +133,10 @@ min_adv_mss - INTEGER IP Fragmentation: -ipfrag_high_thresh - INTEGER +ipfrag_high_thresh - LONG INTEGER Maximum memory used to reassemble IP fragments. -ipfrag_low_thresh - INTEGER +ipfrag_low_thresh - LONG INTEGER (Obsolete since linux-4.17) Maximum memory used to reassemble IP fragments before the kernel begins to remove incomplete fragment queues to free up resources. diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h index 95e353e3305b..a52e7273e7a5 100644 --- a/include/net/inet_frag.h +++ b/include/net/inet_frag.h @@ -8,11 +8,11 @@ struct netns_frags { struct rhashtable rhashtable ____cacheline_aligned_in_smp; /* Keep atomic mem on separate cachelines in structs that include it */ - atomic_t mem ____cacheline_aligned_in_smp; + atomic_long_t mem ____cacheline_aligned_in_smp; /* sysctls */ + long high_thresh; + long low_thresh; int timeout; - int high_thresh; - int low_thresh; int max_dist; struct inet_frags *f; }; @@ -102,7 +102,7 @@ void inet_frags_fini(struct inet_frags *); static inline int inet_frags_init_net(struct netns_frags *nf) { - atomic_set(&nf->mem, 0); + atomic_long_set(&nf->mem, 0); return rhashtable_init(&nf->rhashtable, &nf->f->rhash_params); } void inet_frags_exit_net(struct netns_frags *nf); @@ -119,19 +119,19 @@ static inline void inet_frag_put(struct inet_frag_queue *q) /* Memory Tracking Functions. */ -static inline int frag_mem_limit(struct netns_frags *nf) +static inline long frag_mem_limit(const struct netns_frags *nf) { - return atomic_read(&nf->mem); + return atomic_long_read(&nf->mem); } -static inline void sub_frag_mem_limit(struct netns_frags *nf, int i) +static inline void sub_frag_mem_limit(struct netns_frags *nf, long val) { - atomic_sub(i, &nf->mem); + atomic_long_sub(val, &nf->mem); } -static inline void add_frag_mem_limit(struct netns_frags *nf, int i) +static inline void add_frag_mem_limit(struct netns_frags *nf, long val) { - atomic_add(i, &nf->mem); + atomic_long_add(val, &nf->mem); } /* RFC 3168 support : diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c index 1aec71a3f904..44f148a6bb57 100644 --- a/net/ieee802154/6lowpan/reassembly.c +++ b/net/ieee802154/6lowpan/reassembly.c @@ -411,23 +411,23 @@ err: } #ifdef CONFIG_SYSCTL -static int zero; +static long zero; static struct ctl_table lowpan_frags_ns_ctl_table[] = { { .procname = "6lowpanfrag_high_thresh", .data = &init_net.ieee802154_lowpan.frags.high_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &init_net.ieee802154_lowpan.frags.low_thresh }, { .procname = "6lowpanfrag_low_thresh", .data = &init_net.ieee802154_lowpan.frags.low_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &zero, .extra2 = &init_net.ieee802154_lowpan.frags.high_thresh }, diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index b0366224f314..053869f2c49b 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -678,23 +678,23 @@ struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user) EXPORT_SYMBOL(ip_check_defrag); #ifdef CONFIG_SYSCTL -static int zero; +static long zero; static struct ctl_table ip4_frags_ns_ctl_table[] = { { .procname = "ipfrag_high_thresh", .data = &init_net.ipv4.frags.high_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &init_net.ipv4.frags.low_thresh }, { .procname = "ipfrag_low_thresh", .data = &init_net.ipv4.frags.low_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &zero, .extra2 = &init_net.ipv4.frags.high_thresh }, diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index aacfce0d7d82..a058de677e94 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -71,7 +71,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v) sock_prot_inuse_get(net, &udplite_prot)); seq_printf(seq, "RAW: inuse %d\n", sock_prot_inuse_get(net, &raw_prot)); - seq_printf(seq, "FRAG: inuse %u memory %u\n", + seq_printf(seq, "FRAG: inuse %u memory %lu\n", atomic_read(&net->ipv4.frags.rhashtable.nelems), frag_mem_limit(&net->ipv4.frags)); return 0; diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index d866412b8f6c..603a39592859 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -63,7 +63,7 @@ struct nf_ct_frag6_skb_cb static struct inet_frags nf_frags; #ifdef CONFIG_SYSCTL -static int zero; +static long zero; static struct ctl_table nf_ct_frag6_sysctl_table[] = { { @@ -76,18 +76,18 @@ static struct ctl_table nf_ct_frag6_sysctl_table[] = { { .procname = "nf_conntrack_frag6_low_thresh", .data = &init_net.nf_frag.frags.low_thresh, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &zero, .extra2 = &init_net.nf_frag.frags.high_thresh }, { .procname = "nf_conntrack_frag6_high_thresh", .data = &init_net.nf_frag.frags.high_thresh, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &init_net.nf_frag.frags.low_thresh }, { } diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c index 8befeb91e071..a85f7e0b14b1 100644 --- a/net/ipv6/proc.c +++ b/net/ipv6/proc.c @@ -47,7 +47,7 @@ static int sockstat6_seq_show(struct seq_file *seq, void *v) sock_prot_inuse_get(net, &udplitev6_prot)); seq_printf(seq, "RAW6: inuse %d\n", sock_prot_inuse_get(net, &rawv6_prot)); - seq_printf(seq, "FRAG6: inuse %u memory %u\n", + seq_printf(seq, "FRAG6: inuse %u memory %lu\n", atomic_read(&net->ipv6.frags.rhashtable.nelems), frag_mem_limit(&net->ipv6.frags)); return 0; diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 2a77fda5e3bc..905a8aee2671 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -552,15 +552,15 @@ static struct ctl_table ip6_frags_ns_ctl_table[] = { { .procname = "ip6frag_high_thresh", .data = &init_net.ipv6.frags.high_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = proc_doulongvec_minmax, .extra1 = &init_net.ipv6.frags.low_thresh }, { .procname = "ip6frag_low_thresh", .data = &init_net.ipv6.frags.low_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = &zero,