Date: Wed, 13 May 2009 07:42:53 +0000 (UTC) From: Alan Cox <alc@FreeBSD.org> To: cvs-src-old@freebsd.org Subject: cvs commit: src/sys/amd64/amd64 pmap.c src/sys/i386/i386 pmap.c Message-ID: <200905130743.n4D7hbFa059010@repoman.freebsd.org>
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alc 2009-05-13 07:42:53 UTC
FreeBSD src repository
Modified files:
sys/amd64/amd64 pmap.c
sys/i386/i386 pmap.c
Log:
SVN rev 192035 on 2009-05-13 07:42:53Z by alc
Correct a rare use-after-free error in pmap_copy(). This error was
introduced in amd64 revision 1.540 and i386 revision 1.547. However, it
had no harmful effects until after a recent change, r189698, on amd64.
(In other words, the error is harmless in RELENG_7.)
The error is triggered by the failure to allocate a pv entry for the one
and only mapping in a page table page. I am addressing the error by
changing pmap_copy() to abort if either pv entry allocation or page
table page allocation fails. This is appropriate because the creation of
mappings by pmap_copy() is optional. They are a (possible) optimization,
and not a requirement.
Correct a nearby whitespace error in the i386 pmap_copy().
Crash reported by: jeff@
MFC after: 6 weeks
Revision Changes Path
1.658 +3 -1 src/sys/amd64/amd64/pmap.c
1.634 +4 -2 src/sys/i386/i386/pmap.c
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