diff options
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/inet_fragment.c | 43 | ||||
-rw-r--r-- | net/ipv4/ip_fragment.c | 5 |
2 files changed, 32 insertions, 16 deletions
diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c index 198a5ed..58d4c38 100644 --- a/net/ipv4/inet_fragment.c +++ b/net/ipv4/inet_fragment.c @@ -28,6 +28,9 @@ #define INETFRAGS_EVICT_BUCKETS 128 #define INETFRAGS_EVICT_MAX 512 +/* don't rebuild inetfrag table with new secret more often than this */ +#define INETFRAGS_MIN_REBUILD_INTERVAL (5 * HZ) + /* Given the OR values of all fragments, apply RFC 3168 5.3 requirements * Value : 0xff if frame should be dropped. * 0 or INET_ECN_CE value, to be ORed in to final iph->tos field @@ -55,16 +58,24 @@ inet_frag_hashfn(const struct inet_frags *f, const struct inet_frag_queue *q) return f->hashfn(q) & (INETFRAGS_HASHSZ - 1); } -static void inet_frag_secret_rebuild(unsigned long dummy) +static bool inet_frag_may_rebuild(struct inet_frags *f) +{ + return time_after(jiffies, + f->last_rebuild_jiffies + INETFRAGS_MIN_REBUILD_INTERVAL); +} + +static void inet_frag_secret_rebuild(struct inet_frags *f) { - struct inet_frags *f = (struct inet_frags *)dummy; - unsigned long now = jiffies; int i; /* Per bucket lock NOT needed here, due to write lock protection */ - write_lock(&f->lock); + write_lock_bh(&f->lock); + + if (!inet_frag_may_rebuild(f)) + goto out; get_random_bytes(&f->rnd, sizeof(u32)); + for (i = 0; i < INETFRAGS_HASHSZ; i++) { struct inet_frag_bucket *hb; struct inet_frag_queue *q; @@ -85,9 +96,11 @@ static void inet_frag_secret_rebuild(unsigned long dummy) } } } - write_unlock(&f->lock); - mod_timer(&f->secret_timer, now + f->secret_interval); + f->rebuild = false; + f->last_rebuild_jiffies = jiffies; +out: + write_unlock_bh(&f->lock); } static bool inet_fragq_should_evict(const struct inet_frag_queue *q) @@ -162,6 +175,8 @@ static void inet_frag_worker(struct work_struct *work) f->next_bucket = i; read_unlock_bh(&f->lock); + if (f->rebuild && inet_frag_may_rebuild(f)) + inet_frag_secret_rebuild(f); } static void inet_frag_schedule_worker(struct inet_frags *f) @@ -183,11 +198,7 @@ void inet_frags_init(struct inet_frags *f) INIT_HLIST_HEAD(&hb->chain); } rwlock_init(&f->lock); - - setup_timer(&f->secret_timer, inet_frag_secret_rebuild, - (unsigned long)f); - f->secret_timer.expires = jiffies + f->secret_interval; - add_timer(&f->secret_timer); + f->last_rebuild_jiffies = 0; } EXPORT_SYMBOL(inet_frags_init); @@ -199,7 +210,6 @@ EXPORT_SYMBOL(inet_frags_init_net); void inet_frags_fini(struct inet_frags *f) { - del_timer(&f->secret_timer); cancel_work_sync(&f->frags_work); } EXPORT_SYMBOL(inet_frags_fini); @@ -399,8 +409,13 @@ struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, if (depth <= INETFRAGS_MAXDEPTH) return inet_frag_create(nf, f, key); - else - return ERR_PTR(-ENOBUFS); + + if (inet_frag_may_rebuild(f)) { + f->rebuild = true; + inet_frag_schedule_worker(f); + } + + return ERR_PTR(-ENOBUFS); } EXPORT_SYMBOL(inet_frag_find); diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 8fbeee4..44e591a 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -720,10 +720,12 @@ static struct ctl_table ip4_frags_ns_ctl_table[] = { { } }; +/* secret interval has been deprecated */ +static int ip4_frags_secret_interval_unused; static struct ctl_table ip4_frags_ctl_table[] = { { .procname = "ipfrag_secret_interval", - .data = &ip4_frags.secret_interval, + .data = &ip4_frags_secret_interval_unused, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_jiffies, @@ -853,6 +855,5 @@ void __init ipfrag_init(void) ip4_frags.qsize = sizeof(struct ipq); ip4_frags.match = ip4_frag_match; ip4_frags.frag_expire = ip_expire; - ip4_frags.secret_interval = 10 * 60 * HZ; inet_frags_init(&ip4_frags); } |