diff options
| author | Andy Lutomirski <luto@amacapital.net> | 2014-03-17 23:22:11 +0100 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-03-18 12:52:44 -0700 |
| commit | 309944be296efbb3ca4737d12ef49d2ba97cbecc (patch) | |
| tree | 56fefddab5690352d3c441835eacdf89390a76c0 /arch/s390/Kbuild | |
| parent | 7c03156f34d113f885f045d8fb8cc3efd9e64751 (diff) | |
x86, vdso: Zero-pad the VVAR page
By coincidence, the VVAR page is at the end of an ELF segment. As a
result, if it ends up being a partial page, the kernel loader will
leave garbage behind at the end of the vvar page. Zero-pad it to a
full page to fix this issue.
This has probably been broken since the VVAR page was introduced.
On QEMU, if you dump the run-time contents of the VVAR page, you can
find entertaining strings from seabios left behind.
It's remotely possible that this is a security bug -- conceivably
there's some BIOS out there that leaves something sensitive in the
few K of memory that is exposed to userspace.
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Link: http://lkml.kernel.org/r/1395094933-14252-12-git-send-email-stefani@seibold.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/s390/Kbuild')
0 files changed, 0 insertions, 0 deletions