x86/selftests/pkeys: Fork() to check for state being preserved
authorDave Hansen <dave.hansen@linux.intel.com>
Wed, 2 Jan 2019 21:56:57 +0000 (13:56 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 31 Jan 2019 07:14:39 +0000 (08:14 +0100)
commit334c0e1b3cdd6dfbfd319dca47c3d0a1b17be896
tree23d52bfc2238b37163fd990dd5aeb85960c89eee
parentdb01b8d40feb341833ac45f9173b569ec34773f3
x86/selftests/pkeys: Fork() to check for state being preserved

commit e1812933b17be7814f51b6c310c5d1ced7a9a5f5 upstream.

There was a bug where the per-mm pkey state was not being preserved across
fork() in the child.  fork() is performed in the pkey selftests, but all of
the pkey activity is performed in the parent.  The child does not perform
any actions sensitive to pkey state.

To make the test more sensitive to these kinds of bugs, add a fork() where
the parent exits, and execution continues in the child.

To achieve this let the key exhaustion test not terminate at the first
allocation failure and fork after 2*NR_PKEYS loops and continue in the
child.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: peterz@infradead.org
Cc: mpe@ellerman.id.au
Cc: will.deacon@arm.com
Cc: luto@kernel.org
Cc: jroedel@suse.de
Cc: stable@vger.kernel.org
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/20190102215657.585704B7@viggo.jf.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tools/testing/selftests/x86/protection_keys.c