4.16-stable review patch. If anyone has any objections, please let me know.
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From: Dave Hansen dave.hansen@linux.intel.com
[ Upstream commit 7e7fd67ca39335a49619729821efb7cbdd674eb0 ]
The exec-only pkey is allocated inside the kernel and userspace is not told what it is. So, allow PK faults to occur that have an unknown key.
Signed-off-by: Dave Hansen dave.hansen@linux.intel.com Cc: Andrew Morton akpm@linux-foundation.org Cc: Dave Hansen dave.hansen@intel.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Michael Ellermen mpe@ellerman.id.au Cc: Peter Zijlstra peterz@infradead.org Cc: Ram Pai linuxram@us.ibm.com Cc: Shuah Khan shuah@kernel.org Cc: Thomas Gleixner tglx@linutronix.de Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180509171345.7FC7DA00@viggo.jf.intel.com Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/x86/protection_keys.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/x86/protection_keys.c +++ b/tools/testing/selftests/x86/protection_keys.c @@ -921,13 +921,21 @@ void *malloc_pkey(long size, int prot, u }
int last_pkru_faults; +#define UNKNOWN_PKEY -2 void expected_pk_fault(int pkey) { dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n", __func__, last_pkru_faults, pkru_faults); dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey); pkey_assert(last_pkru_faults + 1 == pkru_faults); - pkey_assert(last_si_pkey == pkey); + + /* + * For exec-only memory, we do not know the pkey in + * advance, so skip this check. + */ + if (pkey != UNKNOWN_PKEY) + pkey_assert(last_si_pkey == pkey); + /* * The signal handler shold have cleared out PKRU to let the * test program continue. We now have to restore it.