From: Eric Dumazet edumazet@google.com
[ Upstream commit e7a409c3f46cb0dbc7bfd4f6f9421d53e92614a5 ]
This patch removes the iph field from the state structure, which is not properly initialized. Instead, add a new field to make the "do we want to set DF" be the state bit and move the code to set the DF flag from ip_frag_next().
Joint work with Pablo and Linus.
Fixes: 19c3401a917b ("net: ipv4: place control buffer handling away from fragmentation iterators") Reported-by: Patrick Schönthaler patrick@notvads.ovh Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/net/ip.h | 4 ++-- net/bridge/netfilter/nf_conntrack_bridge.c | 2 +- net/ipv4/ip_output.c | 11 ++++++----- 3 files changed, 9 insertions(+), 8 deletions(-)
--- a/include/net/ip.h +++ b/include/net/ip.h @@ -184,7 +184,7 @@ static inline struct sk_buff *ip_fraglis }
struct ip_frag_state { - struct iphdr *iph; + bool DF; unsigned int hlen; unsigned int ll_rs; unsigned int mtu; @@ -195,7 +195,7 @@ struct ip_frag_state { };
void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs, - unsigned int mtu, struct ip_frag_state *state); + unsigned int mtu, bool DF, struct ip_frag_state *state); struct sk_buff *ip_frag_next(struct sk_buff *skb, struct ip_frag_state *state);
--- a/net/bridge/netfilter/nf_conntrack_bridge.c +++ b/net/bridge/netfilter/nf_conntrack_bridge.c @@ -94,7 +94,7 @@ slow_path: * This may also be a clone skbuff, we could preserve the geometry for * the copies but probably not worth the effort. */ - ip_frag_init(skb, hlen, ll_rs, frag_max_size, &state); + ip_frag_init(skb, hlen, ll_rs, frag_max_size, false, &state);
while (state.left > 0) { struct sk_buff *skb2; --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -645,11 +645,12 @@ void ip_fraglist_prepare(struct sk_buff EXPORT_SYMBOL(ip_fraglist_prepare);
void ip_frag_init(struct sk_buff *skb, unsigned int hlen, - unsigned int ll_rs, unsigned int mtu, + unsigned int ll_rs, unsigned int mtu, bool DF, struct ip_frag_state *state) { struct iphdr *iph = ip_hdr(skb);
+ state->DF = DF; state->hlen = hlen; state->ll_rs = ll_rs; state->mtu = mtu; @@ -668,9 +669,6 @@ static void ip_frag_ipcb(struct sk_buff /* Copy the flags to each fragment. */ IPCB(to)->flags = IPCB(from)->flags;
- if (IPCB(from)->flags & IPSKB_FRAG_PMTU) - state->iph->frag_off |= htons(IP_DF); - /* ANK: dirty, but effective trick. Upgrade options only if * the segment to be fragmented was THE FIRST (otherwise, * options are already fixed) and make it ONCE @@ -738,6 +736,8 @@ struct sk_buff *ip_frag_next(struct sk_b */ iph = ip_hdr(skb2); iph->frag_off = htons((state->offset >> 3)); + if (state->DF) + iph->frag_off |= htons(IP_DF);
/* * Added AC : If we are fragmenting a fragment that's not the @@ -881,7 +881,8 @@ slow_path: * Fragment the datagram. */
- ip_frag_init(skb, hlen, ll_rs, mtu, &state); + ip_frag_init(skb, hlen, ll_rs, mtu, IPCB(skb)->flags & IPSKB_FRAG_PMTU, + &state);
/* * Keep copying data until we run out.