diff options
| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2013-03-15 11:32:30 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-28 12:05:59 -0700 |
| commit | 7b7a1b8b3bd1742ca5ab259e741da0070e936db0 (patch) | |
| tree | ea200e510b59ba89bea5fd56a071e4f0d2d92f50 /net/ipv4/ip_fragment.c | |
| parent | 110789df9f88361dcf6b5dad53a38ea2f88cad77 (diff) | |
inet: limit length of fragment queue hash table bucket lists
[ Upstream commit 5a3da1fe9561828d0ca7eca664b16ec2b9bf0055 ]
This patch introduces a constant limit of the fragment queue hash
table bucket list lengths. Currently the limit 128 is choosen somewhat
arbitrary and just ensures that we can fill up the fragment cache with
empty packets up to the default ip_frag_high_thresh limits. It should
just protect from list iteration eating considerable amounts of cpu.
If we reach the maximum length in one hash bucket a warning is printed.
This is implemented on the caller side of inet_frag_find to distinguish
between the different users of inet_fragment.c.
I dropped the out of memory warning in the ipv4 fragment lookup path,
because we already get a warning by the slab allocator.
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jesper Dangaard Brouer <jbrouer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv4/ip_fragment.c')
| -rw-r--r-- | net/ipv4/ip_fragment.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 0ad6035f6366..da38472beb69 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -20,6 +20,8 @@ * Patrick McHardy : LRU queue of frag heads for evictor. */ +#define pr_fmt(fmt) "IPv4: " fmt + #include <linux/compiler.h> #include <linux/module.h> #include <linux/types.h> @@ -292,14 +294,12 @@ static inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user) hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol); q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash); - if (q == NULL) - goto out_nomem; + if (IS_ERR_OR_NULL(q)) { + inet_frag_maybe_warn_overflow(q, pr_fmt()); + return NULL; + } return container_of(q, struct ipq, q); - -out_nomem: - LIMIT_NETDEBUG(KERN_ERR "ip_frag_create: no memory left !\n"); - return NULL; } /* Is the fragment too far ahead to be part of ipq? */ |