| From foo@baz Mon Apr 9 17:09:24 CEST 2018 |
| From: Willem de Bruijn <willemb@google.com> |
| Date: Thu, 8 Jun 2017 11:35:03 -0400 |
| Subject: skbuff: only inherit relevant tx_flags |
| |
| From: Willem de Bruijn <willemb@google.com> |
| |
| |
| [ Upstream commit fff88030b3ff930ca7a3d74acfee0472f33887ea ] |
| |
| When inheriting tx_flags from one skbuff to another, always apply a |
| mask to avoid overwriting unrelated other bits in the field. |
| |
| The two SKBTX_SHARED_FRAG cases clears all other bits. In practice, |
| tx_flags are zero at this point now. But this is fragile. Timestamp |
| flags are set, for instance, if in tcp_gso_segment, after this clear |
| in skb_segment. |
| |
| The SKBTX_ANY_TSTAMP mask in __skb_tstamp_tx ensures that new |
| skbs do not accidentally inherit flags such as SKBTX_SHARED_FRAG. |
| |
| Signed-off-by: Willem de Bruijn <willemb@google.com> |
| Acked-by: Soheil Hassas Yeganeh <soheil@google.com> |
| Acked-by: Eric Dumazet <edumazet@google.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/core/skbuff.c | 10 ++++++---- |
| 1 file changed, 6 insertions(+), 4 deletions(-) |
| |
| --- a/net/core/skbuff.c |
| +++ b/net/core/skbuff.c |
| @@ -2615,7 +2615,8 @@ void skb_split(struct sk_buff *skb, stru |
| { |
| int pos = skb_headlen(skb); |
| |
| - skb_shinfo(skb1)->tx_flags = skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; |
| + skb_shinfo(skb1)->tx_flags |= skb_shinfo(skb)->tx_flags & |
| + SKBTX_SHARED_FRAG; |
| if (len < pos) /* Split line is inside header. */ |
| skb_split_inside_header(skb, skb1, len, pos); |
| else /* Second chunk has no header, nothing to copy. */ |
| @@ -3228,8 +3229,8 @@ normal: |
| skb_copy_from_linear_data_offset(head_skb, offset, |
| skb_put(nskb, hsize), hsize); |
| |
| - skb_shinfo(nskb)->tx_flags = skb_shinfo(head_skb)->tx_flags & |
| - SKBTX_SHARED_FRAG; |
| + skb_shinfo(nskb)->tx_flags |= skb_shinfo(head_skb)->tx_flags & |
| + SKBTX_SHARED_FRAG; |
| |
| while (pos < offset + len) { |
| if (i >= nfrags) { |
| @@ -3881,7 +3882,8 @@ void __skb_tstamp_tx(struct sk_buff *ori |
| return; |
| |
| if (tsonly) { |
| - skb_shinfo(skb)->tx_flags = skb_shinfo(orig_skb)->tx_flags; |
| + skb_shinfo(skb)->tx_flags |= skb_shinfo(orig_skb)->tx_flags & |
| + SKBTX_ANY_TSTAMP; |
| skb_shinfo(skb)->tskey = skb_shinfo(orig_skb)->tskey; |
| } |
| |