Commit e78bfb07 authored Jul 13, 2018 by Stefano Brivio Committed by David S. Miller Jul 13, 2018

skbuff: Unconditionally copy pfmemalloc in __skb_clone()



Commit 8b700862 ("net: Don't copy pfmemalloc flag in
__copy_skb_header()") introduced a different handling for the
pfmemalloc flag in copy and clone paths.

In __skb_clone(), now, the flag is set only if it was set in the
original skb, but not cleared if it wasn't. This is wrong and
might lead to socket buffers being flagged with pfmemalloc even
if the skb data wasn't allocated from pfmemalloc reserves. Copy
the flag instead of ORing it.

Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Fixes: 8b700862 ("net: Don't copy pfmemalloc flag in __copy_skb_header()")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Tested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 8f19f12b

net/core/skbuff.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -858,8 +858,7 @@ static struct sk_buff __skb_clone(struct sk_buff n, struct sk_buff *skb)
		n->cloned = 1;
		n->nohdr = 0;
		n->peeked = 0;
		if (skb->pfmemalloc)
		n->pfmemalloc = 1;
		C(pfmemalloc);
		n->destructor = NULL;
		C(tail);
		C(end);

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