kernel.git/tools/testing/selftests/x86/Makefile, branch linux-5.13.y

kselftest: Move test_vdso to the vDSO test suite

2020-10-27T23:58:33Z

Move test_vdso from x86 to the vDSO test suite. Suggested-by: Andy Lutomirski Cc: Shuah Khan Signed-off-by: Vincenzo Frascino Acked-by: Thomas Gleixner Signed-off-by: Shuah Khan

Merge tag 'x86-fsgsbase-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-08-05T04:16:22Z

Pull x86 fsgsbase from Thomas Gleixner: "Support for FSGSBASE. Almost 5 years after the first RFC to support it, this has been brought into a shape which is maintainable and actually works. This final version was done by Sasha Levin who took it up after Intel dropped the ball. Sasha discovered that the SGX (sic!) offerings out there ship rogue kernel modules enabling FSGSBASE behind the kernels back which opens an instantanious unpriviledged root hole. The FSGSBASE instructions provide a considerable speedup of the context switch path and enable user space to write GSBASE without kernel interaction. This enablement requires careful handling of the exception entries which go through the paranoid entry path as they can no longer rely on the assumption that user GSBASE is positive (as enforced via prctl() on non FSGSBASE enabled systemn). All other entries (syscalls, interrupts and exceptions) can still just utilize SWAPGS unconditionally when the entry comes from user space. Converting these entries to use FSGSBASE has no benefit as SWAPGS is only marginally slower than WRGSBASE and locating and retrieving the kernel GSBASE value is not a free operation either. The real benefit of RD/WRGSBASE is the avoidance of the MSR reads and writes. The changes come with appropriate selftests and have held up in field testing against the (sanitized) Graphene-SGX driver" * tag 'x86-fsgsbase-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86/fsgsbase: Fix Xen PV support x86/ptrace: Fix 32-bit PTRACE_SETREGS vs fsbase and gsbase selftests/x86/fsgsbase: Add a missing memory constraint selftests/x86/fsgsbase: Fix a comment in the ptrace_write_gsbase test selftests/x86: Add a syscall_arg_fault_64 test for negative GSBASE selftests/x86/fsgsbase: Test ptracer-induced GS base write with FSGSBASE selftests/x86/fsgsbase: Test GS selector on ptracer-induced GS base write Documentation/x86/64: Add documentation for GS/FS addressing mode x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2 x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit x86/entry/64: Introduce the FIND_PERCPU_BASE macro x86/entry/64: Switch CR3 before SWAPGS in paranoid entry x86/speculation/swapgs: Check FSGSBASE in enabling SWAPGS mitigation x86/process/64: Use FSGSBASE instructions on thread copy and ptrace x86/process/64: Use FSBSBASE in switch_to() if available x86/process/64: Make save_fsgs_for_kvm() ready for FSGSBASE x86/fsgsbase/64: Enable FSGSBASE instructions in helper functions x86/fsgsbase/64: Add intrinsics for FSGSBASE instructions x86/cpu: Add 'unsafe_fsgsbase' to enable CR4.FSGSBASE ...

x86/ptrace: Fix 32-bit PTRACE_SETREGS vs fsbase and gsbase

2020-07-01T13:27:20Z

Debuggers expect that doing PTRACE_GETREGS, then poking at a tracee and maybe letting it run for a while, then doing PTRACE_SETREGS will put the tracee back where it was. In the specific case of a 32-bit tracer and tracee, the PTRACE_GETREGS/SETREGS data structure doesn't have fs_base or gs_base fields, so FSBASE and GSBASE fields are never stored anywhere. Everything used to still work because nonzero FS or GS would result full reloads of the segment registers when the tracee resumes, and the bases associated with FS==0 or GS==0 are irrelevant to 32-bit code. Adding FSGSBASE support broke this: when FSGSBASE is enabled, FSBASE and GSBASE are now restored independently of FS and GS for all tasks when context-switched in. This means that, if a 32-bit tracer restores a previous state using PTRACE_SETREGS but the tracee's pre-restore and post-restore bases don't match, then the tracee is resumed with the wrong base. Fix it by explicitly loading the base when a 32-bit tracer pokes FS or GS on a 64-bit kernel. Also add a test case. Fixes: 673903495c85 ("x86/process/64: Use FSBSBASE in switch_to() if available") Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/229cc6a50ecbb701abd50fe4ddaf0eda888898cd.1593192140.git.luto@kernel.org

selftests/x86: Consolidate and fix get/set_eflags() helpers

2020-07-01T08:00:27Z

There are several copies of get_eflags() and set_eflags() and they all are buggy. Consolidate them and fix them. The fixes are: Add memory clobbers. These are probably unnecessary but they make sure that the compiler doesn't move something past one of these calls when it shouldn't. Respect the redzone on x86_64. There has no failure been observed related to this, but it's definitely a bug. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/982ce58ae8dea2f1e57093ee894760e35267e751.1593191971.git.luto@kernel.org

selftests/x86/pkeys: move selftests to arch-neutral directory

2020-06-05T02:06:26Z

Patch series "selftests, powerpc, x86: Memory Protection Keys", v19. Memory protection keys enables an application to protect its address space from inadvertent access by its own code. This feature is now enabled on powerpc and has been available since 4.16-rc1. The patches move the selftests to arch neutral directory and enhance their test coverage. Tested on powerpc64 and x86_64 (Skylake-SP). This patch (of 24): Move selftest files from tools/testing/selftests/x86/ to tools/testing/selftests/vm/. Signed-off-by: Ram Pai Signed-off-by: Thiago Jung Bauermann Signed-off-by: Sandipan Das Signed-off-by: Andrew Morton Acked-by: Ingo Molnar Acked-by: Dave Hansen Cc: Dave Hansen Cc: Florian Weimer Cc: "Desnes A. Nunes do Rosario" Cc: Michal Hocko Cc: "Aneesh Kumar K.V" Cc: Michal Suchanek Cc: Michael Ellerman Cc: Shuah Khan Link: http://lkml.kernel.org/r/14d25194c3e2e652e0047feec4487e269e76e8c9.1585646528.git.sandipan@linux.ibm.com Signed-off-by: Linus Torvalds

Merge branch 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-09-17T02:06:29Z

Pull x86 entry updates from Ingo Molnar: "This contains x32 and compat syscall improvements, the biggest one of which splits x32 syscalls into their own table, which allows new syscalls to share the x32 and x86-64 number - which turns the 512-547 special syscall numbers range into a legacy wart that won't be extended going forward" * 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/syscalls: Split the x32 syscalls into their own table x86/syscalls: Disallow compat entries for all types of 64-bit syscalls x86/syscalls: Use the compat versions of rt_sigsuspend() and rt_sigprocmask() x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long

x86/mpx: Remove selftests Makefile entry

2019-07-22T09:54:56Z

MPX is being removed from the kernel due to a lack of support in the toolchain going forward (gcc). This is the smallest possible patch to fix some issues that have been reported around running the MPX selftests. It it would also have been part of any removal series, it is offered first. Signed-off-by: Dave Hansen Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20190705175318.784C233E@viggo.jf.intel.com

x86/syscalls: Split the x32 syscalls into their own table

2019-07-22T08:31:23Z

For unfortunate historical reasons, the x32 syscalls and the x86_64 syscalls are not all numbered the same. As an example, ioctl() is nr 16 on x86_64 but 514 on x32. This has potentially nasty consequences, since it means that there are two valid RAX values to do ioctl(2) and two invalid RAX values. The valid values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000) (i.e. ioctl(2) using the x32 ABI). The invalid values are 514 and (16 | 0x40000000). 514 will enter the "COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall() and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter the native entry point with in_compat_syscall() and in_x32_syscall() returning true. Both are bogus, and both will exercise code paths in the kernel and in any running seccomp filters that really ought to be unreachable. Splitting out the x32 syscalls into their own tables, allows both bogus invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and all of them appear to call syscalls with their correct numbers, so this change should have no effect on them. There is an added benefit going forward: new syscalls that need special handling on x32 can share the same number on x32 and x86_64. This means that the special syscall range 512-547 can be treated as a legacy wart instead of something that may need to be extended in the future. Also add a selftest to verify the new behavior. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org

selftests/x86: Test SYSCALL and SYSENTER manually with TF set

2019-07-02T06:45:20Z

Make sure that both variants of the nasty TF-in-compat-syscall are exercised regardless of what vendor's CPU is running the tests. Also change the intentional signal after SYSCALL to use ud2, which is a lot more comprehensible. This crashes the kernel due to an FSGSBASE bug right now. This test *also* detects a bug in KVM when run on an Intel host. KVM people, feel free to use it to help debug. There's a bunch of code in this test to warn instead of going into an infinite looping when the bug gets triggered. Reported-by: Vegard Nossum Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Cc: "BaeChang Seok" Cc: Borislav Petkov Cc: Peter Zijlstra Cc: Paolo Bonzini Cc: kvm@vger.kernel.org Cc: "Bae, Chang Seok" Link: https://lkml.kernel.org/r/5f5de10441ab2e3005538b4c33be9b1965d1bb63.1562035429.git.luto@kernel.org

selftests/x86: Detect -no-pie availability

2018-05-30T21:21:51Z

Some toolchains need -no-pie to build all tests, others do not support the -no-pie flag at all. Therefore, add another test for the availability of the flag. This amends commit 3346a6a4e5ba8c040360f753b26938cec31a4bdc ("selftests: x86: sysret_ss_attrs doesn't build on a PIE build"). Signed-off-by: Florian Weimer Acked-by: Randy Dunlap Tested-by: Randy Dunlap Signed-off-by: Shuah Khan (Samsung OSG)