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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
[NETLINK]: Limit NLMSG_GOODSIZE to 8K.
Signed-off-by: David S. Miller <davem@davemloft.net>
authored by
David S. Miller
and committed by
David S. Miller
fc910a27
ca043569
+14
-5
+9
-2
include/linux/netlink.h
+9
-2
include/linux/netlink.h
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/*
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* skb should fit one page. This choice is good for headerless malloc.
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* But we should limit to 8K so that userspace does not have to
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* use enormous buffer sizes on recvmsg() calls just to avoid
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* MSG_TRUNC when PAGE_SIZE is very large.
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*/
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#define NLMSG_GOODORDER 0
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#define NLMSG_GOODSIZE (SKB_MAX_ORDER(0, NLMSG_GOODORDER))
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#if PAGE_SIZE < 8192UL
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#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
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#else
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#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
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#endif
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#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
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include/linux/skbuff.h
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-3
include/linux/skbuff.h
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#define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \
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~(SMP_CACHE_BYTES - 1))
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#define SKB_MAX_ORDER(X, ORDER) (((PAGE_SIZE << (ORDER)) - (X) - \
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sizeof(struct skb_shared_info)) & \
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~(SMP_CACHE_BYTES - 1))
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#define SKB_WITH_OVERHEAD(X) \
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(((X) - sizeof(struct skb_shared_info)) & \
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~(SMP_CACHE_BYTES - 1))
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#define SKB_MAX_ORDER(X, ORDER) \
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SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
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#define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
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#define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
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