Commit graph

4 commits

Author SHA1 Message Date
Andy Lutomirski
1bdfac19b3 x86-64: Pad vDSO to a page boundary
This avoids an information leak to userspace.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/a63380a3c58a0506a2f5a18ba1b12dbde1f25e58.1312378163.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-08-04 16:13:34 -07:00
Andy Lutomirski
aafade242f x86-64, vdso: Do not allocate memory for the vDSO
We can map the vDSO straight from kernel data, saving a few page
allocations.  As an added bonus, the deleted code contained a memory
leak.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/2c4ed5c2c2e93603790229e0c3403ae506ccc0cb.1311277573.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-07-21 13:41:53 -07:00
Roland McGrath
d9dedc1385 x86_64 vDSO: use initdata
The 64-bit vDSO image is in a special ".vdso" section for no reason
I can determine.  Furthermore, the location of the vdso_end symbol
includes some wrongly-calculated padding space in the image, which
is then (correctly) rounded to page size, resulting in an extra page
of zeros in the image mapped in to user processes.

This changes it to put the vdso.so image into normal initdata as we
have always done for the 32-bit vDSO images.  The extra padding is
gone, so the user VMA is one page instead of two.  The image that
was already copied around at boot time is now in initdata, so we
recover that wasted space after boot.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 13:49:35 -07:00
Thomas Gleixner
7648b1330c x86_64: move vdso
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-11 11:17:10 +02:00