From 64ac5f5977df5b276374fb2f051082129f5cdb22 Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Fri, 13 Oct 2017 11:04:20 +0200 Subject: tipc: refactor function filter_rcv() In the following commits we will need to handle multiple incoming and rejected/returned buffers in the function socket.c::filter_rcv(). As a preparation for this, we generalize the function by handling buffer queues instead of individual buffers. We also introduce a help function tipc_skb_reject(), and rename filter_rcv() to tipc_sk_filter_rcv() in line with other functions in socket.c. Signed-off-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/msg.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'net/tipc/msg.c') diff --git a/net/tipc/msg.c b/net/tipc/msg.c index 17146c16ee2d..1649d456e22d 100644 --- a/net/tipc/msg.c +++ b/net/tipc/msg.c @@ -666,3 +666,10 @@ void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno, } kfree_skb(skb); } + +void tipc_skb_reject(struct net *net, int err, struct sk_buff *skb, + struct sk_buff_head *xmitq) +{ + if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) + __skb_queue_tail(xmitq, skb); +} -- cgit v1.2.3 From d618d09a68e4eed7a435beb2e355250f6f40664a Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Wed, 15 Nov 2017 21:23:56 +0100 Subject: tipc: enforce valid ratio between skb truesize and contents The socket level flow control is based on the assumption that incoming buffers meet the condition (skb->truesize / roundup(skb->len) <= 4), where the latter value is rounded off upwards to the nearest 1k number. This does empirically hold true for the device drivers we know, but we cannot trust that it will always be so, e.g., in a system with jumbo frames and very small packets. We now introduce a check for this condition at packet arrival, and if we find it to be false, we copy the packet to a new, smaller buffer, where the condition will be true. We expect this to affect only a small fraction of all incoming packets, if at all. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/msg.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) (limited to 'net/tipc/msg.c') diff --git a/net/tipc/msg.c b/net/tipc/msg.c index 1649d456e22d..b0d07b35909d 100644 --- a/net/tipc/msg.c +++ b/net/tipc/msg.c @@ -174,7 +174,7 @@ int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf) if (fragid == LAST_FRAGMENT) { TIPC_SKB_CB(head)->validated = false; - if (unlikely(!tipc_msg_validate(head))) + if (unlikely(!tipc_msg_validate(&head))) goto err; *buf = head; TIPC_SKB_CB(head)->tail = NULL; @@ -201,11 +201,21 @@ err: * TIPC will ignore the excess, under the assumption that it is optional info * introduced by a later release of the protocol. */ -bool tipc_msg_validate(struct sk_buff *skb) +bool tipc_msg_validate(struct sk_buff **_skb) { - struct tipc_msg *msg; + struct sk_buff *skb = *_skb; + struct tipc_msg *hdr; int msz, hsz; + /* Ensure that flow control ratio condition is satisfied */ + if (unlikely(skb->truesize / buf_roundup_len(skb) > 4)) { + skb = skb_copy(skb, GFP_ATOMIC); + if (!skb) + return false; + kfree_skb(*_skb); + *_skb = skb; + } + if (unlikely(TIPC_SKB_CB(skb)->validated)) return true; if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE))) @@ -217,11 +227,11 @@ bool tipc_msg_validate(struct sk_buff *skb) if (unlikely(!pskb_may_pull(skb, hsz))) return false; - msg = buf_msg(skb); - if (unlikely(msg_version(msg) != TIPC_VERSION)) + hdr = buf_msg(skb); + if (unlikely(msg_version(hdr) != TIPC_VERSION)) return false; - msz = msg_size(msg); + msz = msg_size(hdr); if (unlikely(msz < hsz)) return false; if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE)) @@ -411,7 +421,7 @@ bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos) skb_pull(*iskb, offset); imsz = msg_size(buf_msg(*iskb)); skb_trim(*iskb, imsz); - if (unlikely(!tipc_msg_validate(*iskb))) + if (unlikely(!tipc_msg_validate(iskb))) goto none; *pos += align(imsz); return true; -- cgit v1.2.3