diff options
Diffstat (limited to 'net/ipv4/ip_fragment.c')
| -rw-r--r-- | net/ipv4/ip_fragment.c | 22 |
1 files changed, 7 insertions, 15 deletions
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 04c7e4618..989201a3b 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -831,22 +831,14 @@ static inline void ip4_frags_ctl_register(void) static int __net_init ipv4_frags_init_net(struct net *net) { - /* Fragment cache limits. - * - * The fragment memory accounting code, (tries to) account for - * the real memory usage, by measuring both the size of frag - * queue struct (inet_frag_queue (ipv4:ipq/ipv6:frag_queue)) - * and the SKB's truesize. - * - * A 64K fragment consumes 129736 bytes (44*2944)+200 - * (1500 truesize == 2944, sizeof(struct ipq) == 200) - * - * We will commit 4MB at one time. Should we cross that limit - * we will prune down to 3MB, making room for approx 8 big 64K - * fragments 8x128k. + /* + * Fragment cache limits. We will commit 256K at one time. Should we + * cross that limit we will prune down to 192K. This should cope with + * even the most extreme cases without allowing an attacker to + * measurably harm machine performance. */ - net->ipv4.frags.high_thresh = 4 * 1024 * 1024; - net->ipv4.frags.low_thresh = 3 * 1024 * 1024; + net->ipv4.frags.high_thresh = 256 * 1024; + net->ipv4.frags.low_thresh = 192 * 1024; /* * Important NOTE! Fragment queue must be destroyed before MSL expires. * RFC791 is wrong proposing to prolongate timer each fragment arrival |