4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> [ Upstream commit 3fcd2b2d928904cbf30b01e2c5e4f1dd2f9ab262 ] We currently have an execute-only test, but it is for the explicit mprotect_pkey() interface. We will soon add a test for the implicit mprotect(PROT_EXEC) enterface. We need this code in both tests. Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Michael Ellermen <mpe@xxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Ram Pai <linuxram@xxxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: linux-mm@xxxxxxxxx Link: http://lkml.kernel.org/r/20180509171347.C64AB733@xxxxxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/x86/protection_keys.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) --- a/tools/testing/selftests/x86/protection_keys.c +++ b/tools/testing/selftests/x86/protection_keys.c @@ -1253,12 +1253,9 @@ void test_ptrace_of_child(int *ptr, u16 free(plain_ptr_unaligned); } -void test_executing_on_unreadable_memory(int *ptr, u16 pkey) +void *get_pointer_to_instructions(void) { void *p1; - int scratch; - int ptr_contents; - int ret; p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE); dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write); @@ -1268,7 +1265,23 @@ void test_executing_on_unreadable_memory /* Point 'p1' at the *second* page of the function: */ p1 += PAGE_SIZE; + /* + * Try to ensure we fault this in on next touch to ensure + * we get an instruction fault as opposed to a data one + */ madvise(p1, PAGE_SIZE, MADV_DONTNEED); + + return p1; +} + +void test_executing_on_unreadable_memory(int *ptr, u16 pkey) +{ + void *p1; + int scratch; + int ptr_contents; + int ret; + + p1 = get_pointer_to_instructions(); lots_o_noops_around_write(&scratch); ptr_contents = read_ptr(p1); dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
