From: Fabrice Bellard <fabrice@bellard.org>
To: thayne@c2.net, qemu-devel@nongnu.org, paul@codesourcery.com
Subject: Re: [Qemu-devel] RFC: x86_64 Best way to fix 'cast to pointer from integer of different size' problems?
Date: Wed, 07 Nov 2007 20:18:06 +0100 [thread overview]
Message-ID: <47320F6E.5060505@bellard.org> (raw)
In-Reply-To: <1194314417.5154.176.camel@phantasm.home.enterpriseandprosperity.com>
Hi,
Regarding the user memory access, here is my suggestion which should
minimize the changes:
- Keep __put_user() and __get_user() as you did.
- Remove put_user(), get_user(), copy_from_user() and copy_to_user()
- Modify the signal.c code so that it uses __put_user, __get_user and
lock/unlock_user.
- Modify lock_user() so that it automatically does access_ok() and
returns NULL if access_ok() fails.
- Test lock_user/lock_user_struct/... return value explicitely at every
call.
- Fix page_check_range() so that it handles writes to pages containing
code by calling page_unprotect when necessary (the current code can fail
in this case !).
- Suppress no longer needed page_unprotect_range() call in syscall.c.
- Suppress or fix tput/tget macros so that they do access_ok().
Regards,
Fabrice.
next prev parent reply other threads:[~2007-11-07 19:20 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-03 17:26 [Qemu-devel] RFC: x86_64 Best way to fix 'cast to pointer from integer of different size' problems? TJ
2007-11-03 17:52 ` Paul Brook
2007-11-05 19:51 ` Thayne Harbaugh
2007-11-06 1:05 ` Paul Brook
2007-11-06 2:00 ` Thayne Harbaugh
2007-11-07 19:18 ` Fabrice Bellard [this message]
2007-11-07 20:59 ` Thayne Harbaugh
2007-11-07 23:02 ` Paul Brook
2007-11-12 16:42 ` Thayne Harbaugh
2007-11-06 20:05 ` Fabrice Bellard
2007-11-06 21:52 ` Stuart Anderson
2007-11-06 22:05 ` Paul Brook
2007-11-06 22:19 ` Stuart Anderson
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