From: Olaf Kirch <[EMAIL PROTECTED]>

Make skb_seq_read unmap the last fragment

Having walked through the entire skbuff, skb_seq_read would leave the
last fragment mapped.  As a consequence, the unwary caller would leak
kmaps, and proceed with preempt_count off by one. The only (kind of
non-intuitive) workaround is to use skb_seq_read_abort.

This patch makes sure skb_seq_read always unmaps frag_data after having
cycled through the skb's paged part.

Signed-off-by: [EMAIL PROTECTED]
---
 net/core/skbuff.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: build-2.6/net/core/skbuff.c
===================================================================
--- build-2.6.orig/net/core/skbuff.c
+++ build-2.6/net/core/skbuff.c
@@ -1706,6 +1706,11 @@ next_skb:
                st->stepped_offset += frag->size;
        }
 
+       if (st->frag_data) {
+               kunmap_skb_frag(st->frag_data);
+               st->frag_data = NULL;
+       }
+
        if (st->cur_skb->next) {
                st->cur_skb = st->cur_skb->next;
                st->frag_idx = 0;

-- 
Olaf Kirch  |  --- o --- Nous sommes du soleil we love when we play
[EMAIL PROTECTED] |    / | \   sol.dhoop.naytheet.ah kin.ir.samse.qurax
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