Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment.

From	Eric Dumazet <eric.dumazet@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment.
Date	2016-12-01 16:30 +0100
Message-ID	<sJBt7-5DE-29@gated-at.bofh.it> (permalink)
References	<sJzhD-4h2-13@gated-at.bofh.it> <sJAGK-53E-5@gated-at.bofh.it> <sJB9M-5sv-13@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Thu, 2016-12-01 at 16:07 +0100, Artem Savkov wrote:

> I am not, but this would have the same behavior as pre-07b26c9 code and
> IS_ERR_OR_NULL is used in ipv4's inet_gso_segment().

My concern might have been that IS_ERR_OR_NULL() considers the !ptr to
be unlikely.

But in this code path, we really can not tell.

segs == NULL can be quite likely in TUN case, because of DODGY bit

Commit 50c3a487d50756 replaced the perfectly fine :

if (!segs || IS_ERR(segs))

into dubious

if (IS_ERR_OR_NULL(segs))

segs = NULL is not an error, but use of IS_ERR_OR_NULL() might mislead
programmers trying to understand this code.

Thread

[PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment. Artem Savkov <asavkov@redhat.com> - 2016-12-01 14:10 +0100
  Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment. Eric Dumazet <eric.dumazet@gmail.com> - 2016-12-01 15:40 +0100
    Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment. Artem Savkov <asavkov@redhat.com> - 2016-12-01 16:10 +0100
      Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment. Eric Dumazet <eric.dumazet@gmail.com> - 2016-12-01 16:30 +0100
    Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment. Eric Dumazet <eric.dumazet@gmail.com> - 2016-12-01 16:20 +0100
  Re: [PATCH] ip6_offload: check segs for NULL in ipv6_gso_segment. David Miller <davem@davemloft.net> - 2016-12-02 19:40 +0100

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