1. 08 7月, 2014 9 次提交
  2. 28 6月, 2014 1 次提交
  3. 26 6月, 2014 5 次提交
  4. 25 6月, 2014 1 次提交
  5. 22 6月, 2014 1 次提交
  6. 20 6月, 2014 3 次提交
  7. 19 6月, 2014 3 次提交
  8. 17 6月, 2014 1 次提交
  9. 16 6月, 2014 11 次提交
  10. 15 6月, 2014 2 次提交
    • D
      net: sctp: fix permissions for rto_alpha and rto_beta knobs · b58537a1
      Daniel Borkmann 提交于
      Commit 3fd091e7 ("[SCTP]: Remove multiple levels of msecs
      to jiffies conversions.") has silently changed permissions for
      rto_alpha and rto_beta knobs from 0644 to 0444. The purpose of
      this was to discourage users from tweaking rto_alpha and
      rto_beta knobs in production environments since they are key
      to correctly compute rtt/srtt.
      
      RFC4960 under section 6.3.1. RTO Calculation says regarding
      rto_alpha and rto_beta under rule C3 and C4:
      
        [...]
        C3)  When a new RTT measurement R' is made, set
      
             RTTVAR <- (1 - RTO.Beta) * RTTVAR + RTO.Beta * |SRTT - R'|
      
             and
      
             SRTT <- (1 - RTO.Alpha) * SRTT + RTO.Alpha * R'
      
             Note: The value of SRTT used in the update to RTTVAR
             is its value before updating SRTT itself using the
             second assignment. After the computation, update
             RTO <- SRTT + 4 * RTTVAR.
      
        C4)  When data is in flight and when allowed by rule C5
             below, a new RTT measurement MUST be made each round
             trip. Furthermore, new RTT measurements SHOULD be
             made no more than once per round trip for a given
             destination transport address. There are two reasons
             for this recommendation: First, it appears that
             measuring more frequently often does not in practice
             yield any significant benefit [ALLMAN99]; second,
             if measurements are made more often, then the values
             of RTO.Alpha and RTO.Beta in rule C3 above should be
             adjusted so that SRTT and RTTVAR still adjust to
             changes at roughly the same rate (in terms of how many
             round trips it takes them to reflect new values) as
             they would if making only one measurement per
             round-trip and using RTO.Alpha and RTO.Beta as given
             in rule C3. However, the exact nature of these
             adjustments remains a research issue.
        [...]
      
      While it is discouraged to adjust rto_alpha and rto_beta
      and not further specified how to adjust them, the RFC also
      doesn't explicitly forbid it, but rather gives a RECOMMENDED
      default value (rto_alpha=3, rto_beta=2). We have a couple
      of users relying on the old permissions before they got
      changed. That said, if someone really has the urge to adjust
      them, we could allow it with a warning in the log.
      
      Fixes: 3fd091e7 ("[SCTP]: Remove multiple levels of msecs to jiffies conversions.")
      Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
      Cc: Vlad Yasevich <vyasevich@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b58537a1
    • T
      net: Fix save software checksum complete · 46fb51eb
      Tom Herbert 提交于
      Geert reported issues regarding checksum complete and UDP.
      The logic introduced in commit 7e3cead5
      ("net: Save software checksum complete") is not correct.
      
      This patch:
      1) Restores code in __skb_checksum_complete_header except for setting
         CHECKSUM_UNNECESSARY. This function may be calculating checksum on
         something less than skb->len.
      2) Adds saving checksum to __skb_checksum_complete. The full packet
         checksum 0..skb->len is calculated without adding in pseudo header.
         This value is saved in skb->csum and then the pseudo header is added
         to that to derive the checksum for validation.
      3) In both __skb_checksum_complete_header and __skb_checksum_complete,
         set skb->csum_valid to whether checksum of zero was computed. This
         allows skb_csum_unnecessary to return true without changing to
         CHECKSUM_UNNECESSARY which was done previously.
      4) Copy new csum related bits in __copy_skb_header.
      Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
      Signed-off-by: NTom Herbert <therbert@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      46fb51eb
  11. 14 6月, 2014 1 次提交
  12. 13 6月, 2014 2 次提交