cvs commit: src/sys/netipsec ipsec_mbuf.c

Sam Leffler sam at errno.com
Mon Sep 26 13:58:13 PDT 2005


Andre Oppermann wrote:
> Sam Leffler wrote:
> 
>>Andre Oppermann wrote:
>>
>>>andre       2005-09-26 20:35:45 UTC
>>>
>>>  FreeBSD src repository
>>>
>>>  Modified files:
>>>    sys/netipsec         ipsec_mbuf.c
>>>  Log:
>>>  Replace custom mbuf writeability test with generic M_WRITABLE() test
>>>  covering all edge cases too.
>>
>>I vaguely recall that M_WRITEABLE did exist when I wrote that code but
>>it did not do the right thing.  I'm not sure why you needed to make this
>>change but beware of unexpected side effects.
> 
> 
> The test in question tries to determine whether to copy the mbuf to make
> to safe for modification.  The old did not respect the M_RDONLY for example.
> M_WRITABLE() correctly tests for all cases.
> 

And as I said; I did it for a reason that I cannot recall now.  I'm 
certain that it was pre-mbufs-over-uma so maybe this is now safe but 
such are the ways that subtle bugs are introduced into code...

	Sam



More information about the cvs-src mailing list