| From foo@baz Wed Dec 6 18:04:41 CET 2017 |
| From: Andy Lutomirski <luto@kernel.org> |
| Date: Sat, 4 Nov 2017 04:19:52 -0700 |
| Subject: selftests/x86/ldt_get: Add a few additional tests for limits |
| |
| From: Andy Lutomirski <luto@kernel.org> |
| |
| |
| [ Upstream commit fec8f5ae1715a01c72ad52cb2ecd8aacaf142302 ] |
| |
| We weren't testing the .limit and .limit_in_pages fields very well. |
| Add more tests. |
| |
| This addition seems to trigger the "bits 16:19 are undefined" issue |
| that was fixed in an earlier patch. I think that, at least on my |
| CPU, the high nibble of the limit ends in LAR bits 16:19. |
| |
| Signed-off-by: Andy Lutomirski <luto@kernel.org> |
| Cc: Borislav Petkov <bpetkov@suse.de> |
| Cc: Linus Torvalds <torvalds@linux-foundation.org> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Link: http://lkml.kernel.org/r/5601c15ea9b3113d288953fd2838b18bedf6bc67.1509794321.git.luto@kernel.org |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Signed-off-by: Sasha Levin <alexander.levin@verizon.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| tools/testing/selftests/x86/ldt_gdt.c | 17 ++++++++++++++++- |
| 1 file changed, 16 insertions(+), 1 deletion(-) |
| |
| --- a/tools/testing/selftests/x86/ldt_gdt.c |
| +++ b/tools/testing/selftests/x86/ldt_gdt.c |
| @@ -367,9 +367,24 @@ static void do_simple_tests(void) |
| install_invalid(&desc, false); |
| |
| desc.seg_not_present = 0; |
| - desc.read_exec_only = 0; |
| desc.seg_32bit = 1; |
| + desc.read_exec_only = 0; |
| + desc.limit = 0xfffff; |
| + |
| install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S | AR_P | AR_DB); |
| + |
| + desc.limit_in_pages = 1; |
| + |
| + install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S | AR_P | AR_DB | AR_G); |
| + desc.read_exec_only = 1; |
| + install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA | AR_S | AR_P | AR_DB | AR_G); |
| + desc.contents = 1; |
| + desc.read_exec_only = 0; |
| + install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA_EXPDOWN | AR_S | AR_P | AR_DB | AR_G); |
| + desc.read_exec_only = 1; |
| + install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA_EXPDOWN | AR_S | AR_P | AR_DB | AR_G); |
| + |
| + desc.limit = 0; |
| install_invalid(&desc, true); |
| } |
| |