Ben Greear wrote: > Patrick McHardy wrote: > >>> I took on Ben's challenge to increase the number of possible routing >>> tables, these are the resulting patches. > > > I am seeing problems..though they could be with the way I'm using the tool > or pehaps I patched the kernel incorrectly. > > I applied the 3 patches to 2.6.17..all patches applied without problem, > but with a few lines of fuzz. I get the same behaviour with and > without the new 'ip' patches applied. > > If I do an 'ip ru show', then I see lots of tables, though not all it > seems. (I have not tried beyond 205 yet). But, if I do an > 'ip route show table XX', then I see nothing or incorrect values.
My patches introduced a bug when dumping tables which could lead to incorrect routes beeing dumped. A second bug (that already existed) makes the kernel fail when dumping more rules than fit in a skb. I think I've already seen the patch to address the second problem a short time ago sent by someone else. Anyway, this patch should fix both.
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 3c49e6b..6e1aaa4 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -357,6 +357,7 @@ int inet_dump_fib(struct sk_buff *skb, s unsigned int e = 0, s_e; struct fib_table *tb; struct hlist_node *node; + int dumped = 0; if (NLMSG_PAYLOAD(cb->nlh, 0) >= sizeof(struct rtmsg) && ((struct rtmsg*)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED) @@ -365,16 +366,17 @@ int inet_dump_fib(struct sk_buff *skb, s s_h = cb->args[0]; s_e = cb->args[1]; - for (h = s_h; h < FIB_TABLE_HASHSZ; h++) { + for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { e = 0; hlist_for_each_entry(tb, node, &fib_table_hash[h], tb_hlist) { if (e < s_e) goto next; - if (e > s_e) - memset(&cb->args[1], 0, sizeof(cb->args) - + if (dumped) + memset(&cb->args[2], 0, sizeof(cb->args) - 2 * sizeof(cb->args[0])); if (tb->tb_dump(tb, skb, cb) < 0) goto out; + dumped = 1; next: e++; } diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index a41ab4b..6f33f12 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -459,13 +459,13 @@ int inet_dump_rules(struct sk_buff *skb, rcu_read_lock(); hlist_for_each_entry(r, node, &fib_rules, hlist) { - if (idx < s_idx) - continue; + goto next; if (inet_fill_rule(skb, r, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, RTM_NEWRULE, NLM_F_MULTI) < 0) break; +next: idx++; } rcu_read_unlock();