[PATCH] net: avoid limits overflow

From: Eric Dumazet
Date: Wed Nov 10 2010 - 04:24:42 EST

Le mercredi 10 novembre 2010 Ã 00:15 -0600, Robin Holt a Ãcrit :
> On Tue, Oct 05, 2010 at 02:50:55PM -0700, David Miller wrote:
> > From: Eric Dumazet <eric.dumazet@xxxxxxxxx>
> > Date: Sat, 02 Oct 2010 15:22:16 +0200
> >
> > > [PATCH] net: avoid limits overflow
> > >
> > > Robin Holt tried to boot a 16TB machine and found some limits were
> > > reached : sysctl_tcp_mem[2], sysctl_udp_mem[2]
> > >
> > > We can switch infrastructure to use long "instead" of "int", now
> > > atomic_long_t primitives are available for free.
> > >
> > > Reported-by: Robin Holt <holt@xxxxxxx>
> > > Signed-off-by: Eric Dumazet <eric.dumazet@xxxxxxxxx>
> >
> > Eric please resubmit this when the sysctl fix is resolved.
>
> It looks like the sysctl fix is upstream. Has this been resubmitted
> and I missed it?
>
> Robin

I believe it was in Andrew mm tree for a while, and Andrew sent it do
David the 21th of october, I am not sure what happened.

Here it is again for latest linux-2.6 tree, thanks for the headup !

[PATCH] net: avoid limits overflow

Robin Holt tried to boot a 16TB machine and found some limits were
reached : sysctl_tcp_mem[2], sysctl_udp_mem[2]

We can switch infrastructure to use long "instead" of "int", now
atomic_long_t primitives are available for free.

Signed-off-by: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Reported-by: Robin Holt <holt@xxxxxxx>
Reviewed-by: Robin Holt <holt@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/net/dn.h | 2 +-
include/net/sock.h | 4 ++--
include/net/tcp.h | 6 +++---
include/net/udp.h | 4 ++--
net/core/sock.c | 14 +++++++-------
net/decnet/af_decnet.c | 2 +-
net/decnet/sysctl_net_decnet.c | 4 ++--
net/ipv4/proc.c | 8 ++++----
net/ipv4/sysctl_net_ipv4.c | 5 ++---
net/ipv4/tcp.c | 4 ++--
net/ipv4/tcp_input.c | 11 +++++++----
net/ipv4/udp.c | 4 ++--
net/sctp/protocol.c | 2 +-
net/sctp/socket.c | 4 ++--
net/sctp/sysctl.c | 4 ++--
15 files changed, 40 insertions(+), 38 deletions(-)

diff --git a/include/net/dn.h b/include/net/dn.h
index e5469f7..a514a3c 100644
--- a/include/net/dn.h
+++ b/include/net/dn.h
@@ -225,7 +225,7 @@ extern int decnet_di_count;
extern int decnet_dr_count;
extern int decnet_no_fc_max_cwnd;

-extern int sysctl_decnet_mem[3];
+extern long sysctl_decnet_mem[3];
extern int sysctl_decnet_wmem[3];
extern int sysctl_decnet_rmem[3];

diff --git a/include/net/sock.h b/include/net/sock.h
index c7a7362..a6338d0 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -762,7 +762,7 @@ struct proto {

/* Memory pressure */
void (*enter_memory_pressure)(struct sock *sk);
- atomic_t *memory_allocated; /* Current allocated memory. */
+ atomic_long_t *memory_allocated; /* Current allocated memory. */
struct percpu_counter *sockets_allocated; /* Current number of sockets. */
/*
* Pressure flag: try to collapse.
@@ -771,7 +771,7 @@ struct proto {
* is strict, actions are advisory and have some latency.
*/
int *memory_pressure;
- int *sysctl_mem;
+ long *sysctl_mem;
int *sysctl_wmem;
int *sysctl_rmem;
int max_header;
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 4fee042..e36c874 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -224,7 +224,7 @@ extern int sysctl_tcp_fack;
extern int sysctl_tcp_reordering;
extern int sysctl_tcp_ecn;
extern int sysctl_tcp_dsack;
-extern int sysctl_tcp_mem[3];
+extern long sysctl_tcp_mem[3];
extern int sysctl_tcp_wmem[3];
extern int sysctl_tcp_rmem[3];
extern int sysctl_tcp_app_win;
@@ -247,7 +247,7 @@ extern int sysctl_tcp_cookie_size;
extern int sysctl_tcp_thin_linear_timeouts;
extern int sysctl_tcp_thin_dupack;

-extern atomic_t tcp_memory_allocated;
+extern atomic_long_t tcp_memory_allocated;
extern struct percpu_counter tcp_sockets_allocated;
extern int tcp_memory_pressure;

@@ -280,7 +280,7 @@ static inline bool tcp_too_many_orphans(struct sock *sk, int shift)
}

if (sk->sk_wmem_queued > SOCK_MIN_SNDBUF &&
- atomic_read(&tcp_memory_allocated) > sysctl_tcp_mem[2])
+ atomic_long_read(&tcp_memory_allocated) > sysctl_tcp_mem[2])
return true;
return false;
}
diff --git a/include/net/udp.h b/include/net/udp.h
index 200b828..bb967dd 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -105,10 +105,10 @@ static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,

extern struct proto udp_prot;

-extern atomic_t udp_memory_allocated;
+extern atomic_long_t udp_memory_allocated;

/* sysctl variables for udp */
-extern int sysctl_udp_mem[3];
+extern long sysctl_udp_mem[3];
extern int sysctl_udp_rmem_min;
extern int sysctl_udp_wmem_min;

diff --git a/net/core/sock.c b/net/core/sock.c
index 3eed542..fb60801 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1653,10 +1653,10 @@ int __sk_mem_schedule(struct sock *sk, int size, int kind)
{
struct proto *prot = sk->sk_prot;
int amt = sk_mem_pages(size);
- int allocated;
+ long allocated;

sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
- allocated = atomic_add_return(amt, prot->memory_allocated);
+ allocated = atomic_long_add_return(amt, prot->memory_allocated);

/* Under limit. */
if (allocated <= prot->sysctl_mem[0]) {
@@ -1714,7 +1714,7 @@ suppress_allocation:

/* Alas. Undo changes. */
sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
- atomic_sub(amt, prot->memory_allocated);
+ atomic_long_sub(amt, prot->memory_allocated);
return 0;
}
EXPORT_SYMBOL(__sk_mem_schedule);
@@ -1727,12 +1727,12 @@ void __sk_mem_reclaim(struct sock *sk)
{
struct proto *prot = sk->sk_prot;

- atomic_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
+ atomic_long_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
prot->memory_allocated);
sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;

if (prot->memory_pressure && *prot->memory_pressure &&
- (atomic_read(prot->memory_allocated) < prot->sysctl_mem[0]))
+ (atomic_long_read(prot->memory_allocated) < prot->sysctl_mem[0]))
*prot->memory_pressure = 0;
}
EXPORT_SYMBOL(__sk_mem_reclaim);
@@ -2452,12 +2452,12 @@ static char proto_method_implemented(const void *method)

static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
{
- seq_printf(seq, "%-9s %4u %6d %6d %-3s %6u %-3s %-10s "
+ seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
proto->name,
proto->obj_size,
sock_prot_inuse_get(seq_file_net(seq), proto),
- proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
+ proto->memory_allocated != NULL ? atomic_long_read(proto->memory_allocated) : -1L,
proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
proto->max_header,
proto->slab == NULL ? "no" : "yes",
diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index d6b93d1..a76b78d 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -155,7 +155,7 @@ static const struct proto_ops dn_proto_ops;
static DEFINE_RWLOCK(dn_hash_lock);
static struct hlist_head dn_sk_hash[DN_SK_HASH_SIZE];
static struct hlist_head dn_wild_sk;
-static atomic_t decnet_memory_allocated;
+static atomic_long_t decnet_memory_allocated;

static int __dn_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen, int flags);
static int __dn_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen, int flags);
diff --git a/net/decnet/sysctl_net_decnet.c b/net/decnet/sysctl_net_decnet.c
index be3eb8e..28f8b5e 100644
--- a/net/decnet/sysctl_net_decnet.c
+++ b/net/decnet/sysctl_net_decnet.c
@@ -38,7 +38,7 @@ int decnet_log_martians = 1;
int decnet_no_fc_max_cwnd = NSP_MIN_WINDOW;

/* Reasonable defaults, I hope, based on tcp's defaults */
-int sysctl_decnet_mem[3] = { 768 << 3, 1024 << 3, 1536 << 3 };
+long sysctl_decnet_mem[3] = { 768 << 3, 1024 << 3, 1536 << 3 };
int sysctl_decnet_wmem[3] = { 4 * 1024, 16 * 1024, 128 * 1024 };
int sysctl_decnet_rmem[3] = { 4 * 1024, 87380, 87380 * 2 };

@@ -324,7 +324,7 @@ static ctl_table dn_table[] = {
.data = &sysctl_decnet_mem,
.maxlen = sizeof(sysctl_decnet_mem),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_doulongvec_minmax
},
{
.procname = "decnet_rmem",
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 4ae1f20..1b48eb1 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -59,13 +59,13 @@ static int sockstat_seq_show(struct seq_file *seq, void *v)
local_bh_enable();

socket_seq_show(seq);
- seq_printf(seq, "TCP: inuse %d orphan %d tw %d alloc %d mem %d\n",
+ seq_printf(seq, "TCP: inuse %d orphan %d tw %d alloc %d mem %ld\n",
sock_prot_inuse_get(net, &tcp_prot), orphans,
tcp_death_row.tw_count, sockets,
- atomic_read(&tcp_memory_allocated));
- seq_printf(seq, "UDP: inuse %d mem %d\n",
+ atomic_long_read(&tcp_memory_allocated));
+ seq_printf(seq, "UDP: inuse %d mem %ld\n",
sock_prot_inuse_get(net, &udp_prot),
- atomic_read(&udp_memory_allocated));
+ atomic_long_read(&udp_memory_allocated));
seq_printf(seq, "UDPLITE: inuse %d\n",
sock_prot_inuse_get(net, &udplite_prot));
seq_printf(seq, "RAW: inuse %d\n",
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index d96c1da..e91911d 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -398,7 +398,7 @@ static struct ctl_table ipv4_table[] = {
.data = &sysctl_tcp_mem,
.maxlen = sizeof(sysctl_tcp_mem),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_doulongvec_minmax
},
{
.procname = "tcp_wmem",
@@ -602,8 +602,7 @@ static struct ctl_table ipv4_table[] = {
.data = &sysctl_udp_mem,
.maxlen = sizeof(sysctl_udp_mem),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero
+ .proc_handler = proc_doulongvec_minmax,
},
{
.procname = "udp_rmem_min",
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 1664a05..245603c 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -282,7 +282,7 @@ int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT;
struct percpu_counter tcp_orphan_count;
EXPORT_SYMBOL_GPL(tcp_orphan_count);

-int sysctl_tcp_mem[3] __read_mostly;
+long sysctl_tcp_mem[3] __read_mostly;
int sysctl_tcp_wmem[3] __read_mostly;
int sysctl_tcp_rmem[3] __read_mostly;

@@ -290,7 +290,7 @@ EXPORT_SYMBOL(sysctl_tcp_mem);
EXPORT_SYMBOL(sysctl_tcp_rmem);
EXPORT_SYMBOL(sysctl_tcp_wmem);

-atomic_t tcp_memory_allocated; /* Current allocated memory. */
+atomic_long_t tcp_memory_allocated; /* Current allocated memory. */
EXPORT_SYMBOL(tcp_memory_allocated);

/*
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 3357f69..6d8ab1c 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -259,8 +259,11 @@ static void tcp_fixup_sndbuf(struct sock *sk)
int sndmem = tcp_sk(sk)->rx_opt.mss_clamp + MAX_TCP_HEADER + 16 +
sizeof(struct sk_buff);

- if (sk->sk_sndbuf < 3 * sndmem)
- sk->sk_sndbuf = min(3 * sndmem, sysctl_tcp_wmem[2]);
+ if (sk->sk_sndbuf < 3 * sndmem) {
+ sk->sk_sndbuf = 3 * sndmem;
+ if (sk->sk_sndbuf > sysctl_tcp_wmem[2])
+ sk->sk_sndbuf = sysctl_tcp_wmem[2];
+ }
}

/* 2. Tuning advertised window (window_clamp, rcv_ssthresh)
@@ -396,7 +399,7 @@ static void tcp_clamp_window(struct sock *sk)
if (sk->sk_rcvbuf < sysctl_tcp_rmem[2] &&
!(sk->sk_userlocks & SOCK_RCVBUF_LOCK) &&
!tcp_memory_pressure &&
- atomic_read(&tcp_memory_allocated) < sysctl_tcp_mem[0]) {
+ atomic_long_read(&tcp_memory_allocated) < sysctl_tcp_mem[0]) {
sk->sk_rcvbuf = min(atomic_read(&sk->sk_rmem_alloc),
sysctl_tcp_rmem[2]);
}
@@ -4861,7 +4864,7 @@ static int tcp_should_expand_sndbuf(struct sock *sk)
return 0;

/* If we are under soft global TCP memory pressure, do not expand. */
- if (atomic_read(&tcp_memory_allocated) >= sysctl_tcp_mem[0])
+ if (atomic_long_read(&tcp_memory_allocated) >= sysctl_tcp_mem[0])
return 0;

/* If we filled the congestion window, do not expand. */
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 28cb2d7..5e0a3a5 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -110,7 +110,7 @@
struct udp_table udp_table __read_mostly;
EXPORT_SYMBOL(udp_table);

-int sysctl_udp_mem[3] __read_mostly;
+long sysctl_udp_mem[3] __read_mostly;
EXPORT_SYMBOL(sysctl_udp_mem);

int sysctl_udp_rmem_min __read_mostly;
@@ -119,7 +119,7 @@ EXPORT_SYMBOL(sysctl_udp_rmem_min);
int sysctl_udp_wmem_min __read_mostly;
EXPORT_SYMBOL(sysctl_udp_wmem_min);

-atomic_t udp_memory_allocated;
+atomic_long_t udp_memory_allocated;
EXPORT_SYMBOL(udp_memory_allocated);

#define MAX_UDP_PORTS 65536
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 1ef29c7..e58f947 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -92,7 +92,7 @@ static struct sctp_af *sctp_af_v6_specific;
struct kmem_cache *sctp_chunk_cachep __read_mostly;
struct kmem_cache *sctp_bucket_cachep __read_mostly;

-int sysctl_sctp_mem[3];
+long sysctl_sctp_mem[3];
int sysctl_sctp_rmem[3];
int sysctl_sctp_wmem[3];

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index e34ca9c..6bd5543 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -111,12 +111,12 @@ static void sctp_sock_migrate(struct sock *, struct sock *,
static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;

extern struct kmem_cache *sctp_bucket_cachep;
-extern int sysctl_sctp_mem[3];
+extern long sysctl_sctp_mem[3];
extern int sysctl_sctp_rmem[3];
extern int sysctl_sctp_wmem[3];

static int sctp_memory_pressure;
-static atomic_t sctp_memory_allocated;
+static atomic_long_t sctp_memory_allocated;
struct percpu_counter sctp_sockets_allocated;

static void sctp_enter_memory_pressure(struct sock *sk)
diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index 832590b..50cb57f 100644
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -54,7 +54,7 @@ static int sack_timer_max = 500;
static int addr_scope_max = 3; /* check sctp_scope_policy_t in include/net/sctp/constants.h for max entries */
static int rwnd_scale_max = 16;

-extern int sysctl_sctp_mem[3];
+extern long sysctl_sctp_mem[3];
extern int sysctl_sctp_rmem[3];
extern int sysctl_sctp_wmem[3];

@@ -203,7 +203,7 @@ static ctl_table sctp_table[] = {
.data = &sysctl_sctp_mem,
.maxlen = sizeof(sysctl_sctp_mem),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_doulongvec_minmax
},
{
.procname = "sctp_rmem",


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/