diff options
Diffstat (limited to 'net/ipv4/udp.c')
-rw-r--r-- | net/ipv4/udp.c | 95 |
1 files changed, 51 insertions, 44 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 28355350fb6..cb9fc58efb2 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -98,6 +98,7 @@ #include <linux/skbuff.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> +#include <net/net_namespace.h> #include <net/icmp.h> #include <net/route.h> #include <net/checksum.h> @@ -113,9 +114,8 @@ DEFINE_SNMP_STAT(struct udp_mib, udp_statistics) __read_mostly; struct hlist_head udp_hash[UDP_HTABLE_SIZE]; DEFINE_RWLOCK(udp_hash_lock); -static int udp_port_rover; - -static inline int __udp_lib_lport_inuse(__u16 num, struct hlist_head udptable[]) +static inline int __udp_lib_lport_inuse(__u16 num, + const struct hlist_head udptable[]) { struct sock *sk; struct hlist_node *node; @@ -132,11 +132,10 @@ static inline int __udp_lib_lport_inuse(__u16 num, struct hlist_head udptable[]) * @sk: socket struct in question * @snum: port number to look up * @udptable: hash list table, must be of UDP_HTABLE_SIZE - * @port_rover: pointer to record of last unallocated port * @saddr_comp: AF-dependent comparison of bound local IP addresses */ int __udp_lib_get_port(struct sock *sk, unsigned short snum, - struct hlist_head udptable[], int *port_rover, + struct hlist_head udptable[], int (*saddr_comp)(const struct sock *sk1, const struct sock *sk2 ) ) { @@ -146,49 +145,56 @@ int __udp_lib_get_port(struct sock *sk, unsigned short snum, int error = 1; write_lock_bh(&udp_hash_lock); - if (snum == 0) { - int best_size_so_far, best, result, i; - - if (*port_rover > sysctl_local_port_range[1] || - *port_rover < sysctl_local_port_range[0]) - *port_rover = sysctl_local_port_range[0]; - best_size_so_far = 32767; - best = result = *port_rover; - for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) { - int size; - - head = &udptable[result & (UDP_HTABLE_SIZE - 1)]; - if (hlist_empty(head)) { - if (result > sysctl_local_port_range[1]) - result = sysctl_local_port_range[0] + - ((result - sysctl_local_port_range[0]) & - (UDP_HTABLE_SIZE - 1)); + + if (!snum) { + int i, low, high; + unsigned rover, best, best_size_so_far; + + inet_get_local_port_range(&low, &high); + + best_size_so_far = UINT_MAX; + best = rover = net_random() % (high - low) + low; + + /* 1st pass: look for empty (or shortest) hash chain */ + for (i = 0; i < UDP_HTABLE_SIZE; i++) { + int size = 0; + + head = &udptable[rover & (UDP_HTABLE_SIZE - 1)]; + if (hlist_empty(head)) goto gotit; - } - size = 0; + sk_for_each(sk2, node, head) { if (++size >= best_size_so_far) goto next; } best_size_so_far = size; - best = result; + best = rover; next: - ; + /* fold back if end of range */ + if (++rover > high) + rover = low + ((rover - low) + & (UDP_HTABLE_SIZE - 1)); + + } - result = best; - for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; - i++, result += UDP_HTABLE_SIZE) { - if (result > sysctl_local_port_range[1]) - result = sysctl_local_port_range[0] - + ((result - sysctl_local_port_range[0]) & - (UDP_HTABLE_SIZE - 1)); - if (! __udp_lib_lport_inuse(result, udptable)) - break; + + /* 2nd pass: find hole in shortest hash chain */ + rover = best; + for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++) { + if (! __udp_lib_lport_inuse(rover, udptable)) + goto gotit; + rover += UDP_HTABLE_SIZE; + if (rover > high) + rover = low + ((rover - low) + & (UDP_HTABLE_SIZE - 1)); } - if (i >= (1 << 16) / UDP_HTABLE_SIZE) - goto fail; + + + /* All ports in use! */ + goto fail; + gotit: - *port_rover = snum = result; + snum = rover; } else { head = &udptable[snum & (UDP_HTABLE_SIZE - 1)]; @@ -201,6 +207,7 @@ gotit: (*saddr_comp)(sk, sk2) ) goto fail; } + inet_sk(sk)->num = snum; sk->sk_hash = snum; if (sk_unhashed(sk)) { @@ -217,7 +224,7 @@ fail: int udp_get_port(struct sock *sk, unsigned short snum, int (*scmp)(const struct sock *, const struct sock *)) { - return __udp_lib_get_port(sk, snum, udp_hash, &udp_port_rover, scmp); + return __udp_lib_get_port(sk, snum, udp_hash, scmp); } int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2) @@ -505,6 +512,8 @@ send: out: up->len = 0; up->pending = 0; + if (!err) + UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS, up->pcflag); return err; } @@ -693,10 +702,8 @@ out: ip_rt_put(rt); if (free) kfree(ipc.opt); - if (!err) { - UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS, is_udplite); + if (!err) return len; - } /* * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting * ENOBUFS might not be good (it's not tunable per se), but otherwise @@ -1560,7 +1567,7 @@ int udp_proc_register(struct udp_seq_afinfo *afinfo) afinfo->seq_fops->llseek = seq_lseek; afinfo->seq_fops->release = seq_release_private; - p = proc_net_fops_create(afinfo->name, S_IRUGO, afinfo->seq_fops); + p = proc_net_fops_create(&init_net, afinfo->name, S_IRUGO, afinfo->seq_fops); if (p) p->data = afinfo; else @@ -1572,7 +1579,7 @@ void udp_proc_unregister(struct udp_seq_afinfo *afinfo) { if (!afinfo) return; - proc_net_remove(afinfo->name); + proc_net_remove(&init_net, afinfo->name); memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops)); } |