diff options
author | Helge Deller <deller@gmx.de> | 2019-07-16 21:43:11 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-04 09:34:52 +0200 |
commit | ce41b6472bf3d24c338253fd970677214c82b1f8 (patch) | |
tree | 7854848b05884b040028c6715376371a90f3661a /arch/powerpc | |
parent | 25399eae2a5e1c7194f2909079d9c05fc9e4ff15 (diff) |
parisc: Fix kernel panic due invalid values in IAOQ0 or IAOQ1
commit 10835c854685393a921b68f529bf740fa7c9984d upstream.
On parisc the privilege level of a process is stored in the lowest two bits of
the instruction pointers (IAOQ0 and IAOQ1). On Linux we use privilege level 0
for the kernel and privilege level 3 for user-space. So userspace should not be
allowed to modify IAOQ0 or IAOQ1 of a ptraced process to change it's privilege
level to e.g. 0 to try to gain kernel privileges.
This patch prevents such modifications by always setting the two lowest bits to
one (which relates to privilege level 3 for user-space) if IAOQ0 or IAOQ1 are
modified via ptrace calls in the native and compat ptrace paths.
Link: https://bugs.gentoo.org/481768
Reported-by: Jeroen Roovers <jer@gentoo.org>
Cc: <stable@vger.kernel.org>
Tested-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/powerpc')
0 files changed, 0 insertions, 0 deletions